REVIEW OF LITERATURE

The present chapter embodies a brief review of research done in the area related to

this study. The review of literature is the basis of most of the research as it gives the

investigator an underlying of the previous work that has been done. In the words of Borg

(1975), "The literature in any field forms the foundation upon which all future work will

be built.”

Reviewing the literature is essential as it helps to gain an insight into the methods,

measures and approaches employed by other research workers which helped in the

formation of research design of the present study. The important aspect of this tradition is

that after examining the strength and weakness of many research reports, the researcher is

less likely to produce a shallow and native work for himself or plunge into procedural

pitfalls that plagued his predecessors.

Review of related literature avoids duplication of work, shows strength and

weakness of various past researches and determines the design of further research. It

enables the researcher to know the means of getting to the frontier in the field of study.

Based on updated review and studies from several Nutrition journals & books it is

indicated that Medical Nutrition Therapy (MNT) is essential in controlling diabetes,

however, no one diet can be recommended for every one with diabetes and should be

tailored individually. Nutrition interventions including the nutritional prescription and

educational tools should be based on a thorough assessment of each person’s usual and

customary intake & nutritional status. MNT in terms of lifestyle modifications is the most

important to turn the person towards healthy life style which is beneficial for their whole

life (LAO choi san, 2005).

The occurrence of diabetes mellitus is rising all over the world and is becoming a

problematic of significant importance in the prosperous cultures. Diabetes mellitus is a

metabolic syndrome recognized to man since ages. It is estimated that Type 2 diabetes

will affect more than 366 million people by the year 2030 and the global cost of treating

diabetes and its complication could reach US $ trillion annually (Rathmann and Giani.,

2004, King et.al, 1998, Somani et.al, 2006).

19

Therefore this chapter is an attempt to give the available literature relevant to the

study topic, so the available literature is presented under the sub headings.

2.1. Literature related to the prevalence of type-2 diabetes mellitus.

2.2. Literature related to the risk factors and causes associated with type-2 diabetes

mellitus.

2.3. Literature related to the complications associated with type-2 diabetes mellitus.

2.3. Literature related to the effect of the anthropometrics measurement and physical

activity on the type-2 diabetes mellitus.

2.4. Literature related to the effect of dietary habits on the tppe-2diabetes mellitus.

2.5. Literature related to the role of glycemic index in reducing the risk of type-2 diabetes

mellitus.

2.6. Literature related to the role of dietary counseling in management of type-2 diabetes

mellitus.

2.1. LITERATURE RELATED TO THE PREVALENCE OF TYPE-2 DIABETES

MELLITUS.

a. Prevalence of diabetes globally and in India:

Type 2 diabetes mellitus (T2DM) and pre-diabetic conditions such as impaired

fasting glucose (IFG) and/or impaired glucose tolerance (IGT) are rapidly increasing in

prevalence. There is compelling evidence that T2DM is more likely to develop in

individuals who are insufficiently active (Hordern MD, et.al, 2011). It revealed that

India leads the world with largest number of diabetic subjects earning the dubious

distinction of being termed the "diabetes capital of the world." India is currently

experiencing an epidemic of diabetes mellitus. Prevalence of NIDDM was found 2.3% in

the urban and 1.5% in the rural areas (Ahuja MMS 1980, Gambhir PS, et.al, 2011,)).

20

While the earliest national study reported an overall prevalence of 2.1 % in urban areas

and 1.5% in rural areas (Mohan V, et.al, 2009).

In order to understand the true extent of the problem and its impact on diabetes

care, there is a need to review the epidemiology of diabetes from different regions of

India. Epidemiology of diabetes in India has an extensive history. The earliest national

study reported an overall prevalence of 2.1 % in urban areas and 1.5% in rural areas.

From the available region wise population based studies it is clear that in the last two

decades, there has been a marked increase in the prevalence of diabetes among both

urban as well as the rural Indians, with southern India having the sharpest increase.

Subsequent studies confirmed this high prevalence of diabetes in urban south India.

Today, the prevalence of diabetes in the urban metros of India is approaching the figures

reported in the affluent migrant Indians (Mohan V, et.al, 2009).

21

Global projections for the number of people with diabetes (20-79 age group), 2007-2025 (millions)

Source: Diabetes Atlas 3rd Edition 2006

22

Although in rural India the prevalence of diabetes is much lower than in the urban

population, even here the prevalence of diabetes is rapidly rising. Nevertheless, there is

enough information to derive significant conclusions and projections that will not only

help define the burden of diabetes in India but also throw some light on the causes of the

diabetes epidemic. The prevalence of diabetes in rural areas is same from the earlier days.

Today, the prevalence of diabetes in the urban metros of India is approaching the figures

reported in the affluent migrant Indians. Although in rural India the prevalence of

diabetes is much lower than in the urban population (Mohan V, et.al, 2009, Sadikot SM,

et.al, 2004).

The prevalence of known diabetes was estimated to be 5.6% (5.31% in males and

6.1% in females). The age-sex specific prevalence was estimated using the 2001 Census

data. There are about 48,876 known diabetics living in Puducherry (Mohan V, et.al,

2007, Anil J. Purty, et.al, 2009).

The prevalence of diabetes is two to four times higher among females in the

following groups than among non-Hispanic white women: non-Hispanic blacks,

Hispanic/Latino Americans, American Indians, and Asian/Pacific Islanders (Egede LE,

et.al, 2005). Analysis of secular trends reveals an increase in diabetes prevalence among

rural population at a rate of 2.02 per 1000 population per year. The rate of increase was

high in males (3.33 per 1000 per year) as compared to females (0.88 per 1000 per year).

High prevalence of IFG and IGT has been observed in southern and northern parts of the

country (Anand K, et.al, 2011).

Prevalence of NIDDM varies in different geographic regions and also in different

ethnic groups. The ratio of the prevalence of IGT/Diabetes is variable in different

populations and is usually around one. A high prevalence of IGT among Indians in

Tanzania and Mauritius has been reported (Zimmet P, et.al, 1990). The prevalence of

diabetes (fasting blood glucose) as per WHO criteria was 4.61% while it was 7.5% as per

ADA criteria. The prevalence according to the two hour glucose reading was 6.15%. The

mean glucose level increase with age (Iyer SR, et.al, 2000). It observed that number of

people with type 2 diabetes is increasing at an alarming rate. Almost 4% of the UK

populations currently have diagnosed diabetes. In recent years there are approximately

2.5 million people in the UK with diabetes; 85-95% of whom have type -2 diabetes. Type

23

2 diabetes mellitus is characterized by insulin resistance and impaired insulin secretion.

As approximately 90% of people with type 2 diabetes are overweight or obese. Obesity

is seen as a significant contributory factor in its development (Wyness L, 2009,

Whitmore C, 2010, www.diabetes, 2008, Anderson JW, 2008).

Diabetes mellitus has emerged as one of the main alarms to human health in the

21st century (Teixeira-Lemos E, 2011, Zimmet P, 2007). According to the Diabetes

Atlas 2006 published by the International Diabetes Federation, the number of people with

diabetes in India currently around 40.9 million is expected to rise to 69.9 million by 2025

unless urgent preventive steps are taken. The so called "Asian Indian Phenotype" refers to

certain unique clinical and biochemical abnormalities in Indians which include increased

insulin resistance, greater abdominal adiposity i.e., higher waist circumference despite

lower body mass index, lower adiponectin and higher high sensitive C-reactive protein

levels. This phenotype makes Asian Indians more prone to diabetes and premature

coronary artery disease (Mohan V, et.al, 2007).

The second edition of the Diabetes Atlas used data from a single report

(Ramachandran A, et.al, 2001), based on a population-based survey from the six largest

Indian cities, and extrapolated these results nationwide, applying a 4:1 urban:rural ratio

from these findings for diabetes prevalence (the majority of the Indian population is

classified as rural). For this report, two additional reports of population data collected on

a nationwide basis (Sadikot SM, et.al, 2004, Shah B, et.al, 2006) were used, which

suggest that diabetes prevalence in smaller urban centers (100,000 – 1,000,000

inhabitants) tends to be about half of the larger cities, but still twice that of rural areas

(less than 100,000 persons). This has led to a 30% reduction in expected urban diabetes

cases, but no change to rural diabetes estimates. The anticipated increase in regional

diabetes prevalence from 6.0% to 7.4% in 2025 is very much a consequence of the

increasing life expectancy in India, where the proportion of the population over 50 years

is expected to increase from 16% to 22% between 2007 and 2025 (United Nations,

Population Division.2005), and the urban proportion from 31% to 43% (United Nations,

Population Division, 2003). Evidence suggests that in more affluent parts of the country,

the rural prevalence is higher than less affluent rural areas (Kutty VR, et.al, 2000),

24

indicating that increasing economic growth will increase diabetes prevalence in India

even more than these possibly conservative estimates have indicated.

Top 10: Prevalence of diabetes (20-79 age group) 2007 and 2025

S.No. Country 2007

Prevalence (%)

Country 2025

prevalence (%)

1 Nauru 30.7 Nauru 32.3

2 United Arab

Emirates

19.5 United Arab

Emirates

21.9

3 Saudi Arabia 16.7 Saudi Arabia 18.4

4 Bahrain 15.2 Bahrain 16.0

5 Kuwait 14.4 Kuwait 17.4

6 Oman 13.1 Oman 15.2

7 Tonga 12.9 Tonga 14.7

8 Mauritius 11.1 Mauritius 13.4

9 Egypt 11.0 Egypt 13.4

10 Mexico 10.6 Mexico 12.4

The prevalence of diabetes is rising in rural India. There is a large pool of subjects

with IFG and IGT at high risk of conversion to overt diabetes. Population-level and

individual-level measures are needed to combat this increasing burden of diabetes (Misra

P, et.al, 2011).

India currently has more than 60 million people with Type 2 Diabetes Mellitus

(T2DM) and this is predicted to increase by nearly two-thirds by 2030 (Sathish T, et.al,

2013).

Based on World Health Organization recommendation, Diabetes mellitus is

classified into three major subtypes: Type1 (insulin dependent diabetes mellitus, IDDM),

Type2 (non-insulin dependent diabetes mellitus, NIDDM) and gestational diabetes

mellitus.

25

Differences in the prevalence of type 2 diabetes among selected ethnic groups, 2007

Sources: Diabetes Atlas 3rd Edition 2006

Type1 diabetes mellitus (IDDM) results from cell mediated autoimmune

destruction of the b-cells of pancreas (Yazadparast & Esmaeli., 2005), which is

responsible for symbiosis, and secretion of insulin. These patients, therefore, depend

upon insulin (provided externally) for their survival. Insulin dependent diabetes mellitus

(IDDM) has its onset most often in childhood and adolescence; however it can also occur

at any age.

Type 2diabetes is characterized by defective insulin secretion in pancreatic β-cells

in response to glucose and by deficiencies in insulin action on its target tissues. Indeed,

the relative importance of β-cell dysfunction has been reported in clinical studies (Weyer

et.al, 1999, Stumvoll et.al, 2005 & Ferrannini et.al, 2003). In a state of IR (insulin

26

resistance), normal pancreatic β-cells can compensate for insulin insensitivity by up-

regulating insulin secretion; however, insufficient secretion by β- cells can induce the

onset of abnormalities in glucose metabolism, i.e. IGR (impaired glucose regulation)

(Stumvoll et.al, 2005). Once hyperglycaemia becomes evident, the function of pancreatic

β-cells deteriorates progressively due to ‘glucose toxicity’, which leads to severe

impairment of glucose-stimulated insulin secretion, apparent degranulation of β-cells and

decreased β-cell number, resulting in the aggravation of IR. This vicious circle finally

results in the clinical manifestation of diabetes (Gorogawa et.al, 2002 & Schinner et.al,

2005). Obviously, the natural progression of diabetes occurs after a prolonged pre-

diabetic period, during which IGR forms an important intermediate and reversible stage.

This abnormal metabolic state between NGT (normal glucose tolerance) and diabetes

consists of two distinct disorders: IFG (impaired fasting glucose) and IGT (impaired

glucose tolerance). Compared with subjects with NGT, patients with IFG or IGT, unless

treated, have a considerably higher risk of developing diabetes and cardiovascular disease

(Unwin, et.al, 2002 & Baron, et.al, 2001) and thus, can be used as a significant target

group for the primary prevention of Type 2 diabetes. However, the question as to whether

the onset of Type 2 diabetes in patients with IGR can be prevented or delayed has been

poorly addressed over the last few years Non-insulin dependent diabetes mellitus usually

begins at the middle age or after 40 years.

In view of its distressing effects on mortality and morbidity, several and collective

drug remedies and lifestyle interventions have been applied to prevent or delay the

progression of diabetes; though, this widespread will possibly continue to grow over the

next 20–30 years, proposing a crucial necessity to discover novel therapeutic and heeling

strategies.

2.2. LITERATURE RELATED RISK FACTORS AND CAUSES ASSOCIATED

WITH TYPE-2 DIABETES MELLITUS:

There are quite a lot of risk factors in diabetes. Hyperglycemia is a major risk factor

for both the micro vascular and macro vascular complications in patients with type 2

diabetes. This review summarizes the cardiovascular results of large outcomes trials in

diabetes and presents new evidence on the role of hyperglycemia, with particular

27

emphasis on postprandial hyperglycemia, in adverse

cardiovascular outcomes in patients with type 2 diabetes

(Aryangat AV, et.al, 2010).

Ethnicity is an important risk factor in type 2 diabetes

developments in both adults and children with higher rates being

reported in Asians, Hispanics, indigenous peoples (USA,

Canada, Australia) and African Americans, with some of the highest rates in the world

being observed amongst Pima Indians (Scott CR, et.al, 1997, Acton KJ, et.al, 2002).

For instance from the period 1967-76 to 1987-96 the prevalence of type 2 diabetes in

Pimas increased four to six-fold, reaching a prevalence of 22.3 per 1,000 for 10-14 year

olds and 50.9 per 1,000 for 15-19 year olds by 1992-96 (Fagot-Campagna A, et.al,

2000).

On a global basis the rise in type 2 diabetes rates seems to mirror the growth in

urbanization and economic development, and may be due to mal-adaptation to a rapidly

changing environment (Zimmet P, et.al, 2001, Narayan KM, et.al, 2001). Closely

associated with this is the increase in overweight and obesity.

Patients with type 2 diabetes face an increased risk of cardiovascular disease with

the general population. The UKPDS identified a number of potentially modifiable risk

factors including hypertension, increased low-density lipoprotein cholesterol, decreased

high-density lipoprotein cholesterol, hyperglycemia and smoking (Sara Da Costa, 2006).

Control of both fasting and postprandial hyperglycemia is necessary to achieve

optimal glycated hemoglobin control (Aryangat AV, et.al, 2010). The present

multivariate analysis with respect to many environmental variables strengthen the

hypothesis that alcohol consumption, smoking, physical activity, food habits, physical

fitness and hours spent in watching TV and sleeping are significantly associated with the

occurrence of Type 2 diabetes (Tanveen Kaur, et.al, 2010).

Urbanization and life style of residents contribute to the high prevalence. It is

discovered that Noninsulin-dependent diabetes mellitus is a major health problem, highly

correlated with obesity and, therefore, overeating. Environmental and lifestyle changes

28

resulting from industrialization and migration to urban environment from rural settings

may be responsible to a large extent, for this epidemic of Type 2 diabetes in Indians. In

addition, given the large number of people with Type 2 diabetes in our country, the

morbidity due complications associated with it would still be very high (Wheeler ML,

et.al, 1987, Mohan V, et.al, 2009). Even in rural populations, who usually consume

traditional frugal diets, there is an increasing prevalence of metabolic syndrome (diabetes

etc) due to changes in diets and lifestyle (Misra A, et.al, 2009). Excess adiposity

(particularly central adiposity) is a strong risk factor for the diabetes (Wyness L 2009,

Whitmore C, 2010, Samreen Riaz, et.al, 2009).

Obesity contribute to epidemic of type-2 DM

Obesity is recognized as an important risk factor for type 2 diabetes, inducing

insulin resistance and pancreatic beta-cell dysfunction. These obesity-related defects tend

to progress following weight gain and can eventually lead to worsening hyperglycemia

over time (Ioannis Kyrou & Sudhesh Kumar, 2010, Anderson JW, 2003).

Increasing prevalence of obesity and sedentary behavior has strongly contributed to

the epidemic of type 2 diabetes mellitus (Colberg SR, and Sigal RJ, 2011, Teixeira-

Lemos E, 2011, Hauner H, et.al, 2004, Mike Lean, 2003).

High lipid profile of the serum is one of the factors that may result in the

development of obesity in diabetes mellitus and thus the progression of diabetes.

Adipocytes secreted proteins like leptin not only affect the glucose homeostasis in the

29

blood but also serve as important marker to study the progression of diabetes mellitus in

obese individuals. The proteins secreted by adipose tissues in the visceral region play a

very important role in glucose homeostasis. Also, obesity itself is a factor that can

increase the severity of the disease, especially in the world population where the obesity

is the major factor that contributes to the development of diabetes mellitus in type-2

patients (Samreen Riaz, et.al, 2009). Increasing urbanization has led to increasing use

of stainless steel and resultant exposure to chromium is at the least partly responsible for

rising prevalence of type-2 diabetes (Gambhir PS, et.al, 2011).

Almost all studied risk factors like age, age of onset, BMI, WHR, pulse rate,

socioeconomic status, occupation and blood pressure phenotypes have higher correlation

(p<0.001) with the occurrence of type 2 diabetes among both sexes. The multivariate

regression analysis confirmed that age, BMI, WHR and socioeconomic status are

significant predictor for the occurrence of type-2 diabetes among both sexes (Tanveen

Kaur, et.al, 2010).

Polycystic ovary syndrome (PCOS) is associated with menstrual irregularities,

hyperandrogenism and IR (Lewy VD, et.al, 2001). It is also said to affect up to 5-10% of

females in their reproductive years (Palmert MR, 2002) and is thought to predispose to

glucose intolerance, with studies showing up to 30-40% being affected by IGT and up to

7-10% with type-2 diabetes (Lewy VD, et.al, 2001, Ehrmann DA, et.al, 1999, Dowling

HJ, et.al, 1993). It may explain the female preponderance in type 2 diabetes rates

amongst adolescents (Dabelea D, 1999, Lewy VD, et.al, 2001).

Many studies show a strong family history among affected youth with 45-80%

having at least one parent with diabetes and 74-100% having a first or second degree

relative with type-2 diabetes (Anonymous, 2000, Sinha AK, et.al, 2000). Children with

diabetes are also more likely to have a family history of cardiovascular disease (CVD),

with one study showing that up to 28% have a positive family history of CVD

(Glowinska B, et.al, 2002).

Birth weight is strongly influenced by the intrauterine environment, particularly in

diabetic pregnancies, which can be associated with high birth weight (Casey BM, et.al,

1997). Conversely there is also evidence that low birth weight can result in later adult

type 2 diabetes development (Barker DJ, et.al, 1993). This is most likely due to poor

30

maternal nutrition leading to impaired islet cell development (Casey BM, et.al, 1997,

Hales CN, et.al, 1992), but may also occur in a number of other conditions such as

pregnancies complicated by hypertension/ pre-eclampsia, which is not an uncommon

condition complicating up to 3-5% of all pregnancies (Sibai BM, et.al, 2000).

2.3. LITERATURE RELATED TO COMPLICATIONS ASSOCIATED WITH

TYPE-2 DIABETES MELLITUS:

Cardiovascular disease is the major cause of death in diabetes, accounting for

some 50% of all diabetes fatalities, and much disability. The kinds of CVD that

accompany diabetes include angina, myocardial infarction (heart attack), stroke,

peripheral artery disease, and congestive heart failure (CHF). Angina is the pain that

arises when the blood supply to the heart muscle itself is temporarily insufficient. This is

usually due to narrowing of the arteries feeding the heart muscle. When one of these

arteries becomes fully blocked, a myocardial infarction occurs, which kills heart muscle

and is often fatal. People with diabetes without previous heart attacks have been shown to

have as high a risk of heart attacks as have non-diabetic persons with previous heart

attacks (Haffner et.al, 1998). Patients with type-2 diabetes face a bigger hazard of

cardiac illnesses with the general population (Sara Da Costa, et.al, 2006).

Diabetes is an increasingly important cause of renal failure, and indeed has now

become the single most common cause of end stage renal disease, i.e. that which requires

either dialysis or kidney transplantation, in the USA (USRDS, 2002), and in other

countries.

Through effects on peripheral nerves and arteries, diabetes can lead to foot

ulceration, infection and the need for amputation. People with diabetes carry a risk of

amputation that may be more than 25 times greater than that seen in those without

diabetes (Disney A, 2002). A recent publication, Diabetes and Foot Care: Time to Act,

International Diabetes Federation, 2005, takes a closer look at the diabetic foot and

ways in which complications can be prevented. Incidence rate of renal failure attributed

to diabetes has increased rapidly over the past 34 years in Indians (Pavkov M. E. et.al,

2004).

31

A recent study concluded that Urinary tract infections (UTIs) occur frequently

among women with diabetes. Symptomatic and asymptomatic bacteriuria is prevalent

among diabetic women in our setting and E. coli is the commonest aetiological agent.

Most bacterial isolates are resistant to co-trimoxazole, ampicillin and ciprofloxacin. Gram

negative bacteria showed resistance to cefotaxime due to ESBLs production. Glucosuria

and advanced age of the patient increases the risk of bacteriuria in diabetic women

(Eligius F, et.al, 2011).

Diabetes is a life-long disease marked by elevated levels of sugar in the blood. It is

the second leading cause of blindness and renal disease worldwide (Imazeki F, et.al,

2009). Higher prevalence of low testosterone levels in males with type 2 diabetes were

observed compared to those without. Additionally, there is evidence that low testosterone

levels may predict the development of type 2 diabetes (Ryan GJ, and Jobe LJ, 2011).

Type -2 diabetes and mental health:

The chronically mentally ill are a high-risk population for diseases such as

diabetes and cardiovascular disease due to a number of factors. These include suboptimal

access to medical services, a propensity to smoking, poor diet, sedentary lifestyle and

obesity (Dixon L, et.al, 1999, Fontaine KR, et.al, 2001).

There is an increasing awareness of the link between diabetes, both type 1 and

type 2, and depression.

32

Major Complications

But which one leads to the other or affects its course and outcome has not yet

been fully elucidated. Nevertheless, it has been estimated that people with diabetes are

twice as likely as the general population to suffer from depression, with the risk being

higher in women than in men (Anderson RJ, et.al, 2001, Hermanns N, et.al, 2004).

Depending on the definition used the prevalence of depression among people with

diabetes ranges from 8.5 to 32.5% (Goodnick PJ, et.al, 1995, Lustman PJ, et.al, 2000).

People with poorly controlled diabetes are more likely to have depression (Lustman PJ,

33

et.al, 2000). This may be because depression leads to problems with adherence to

medication and diet, and affects quality of life (Lin EH, and Katon W, 2004).

Depression also seems to be a factor in increasing the risk of developing diabetes-related

complications (De Groot M, et.al, 2001), and also increased mortality (Katon WJ,

2005). Having diabetes and depression may also be associated with higher risk of suicide,

with some reports of a 10-fold increased risk of suicide and suicidal ideation (Goldston

DB et.al, 1994, Goldston DB, et.al, 1997).

Heart attacks in people with and without diabetes over a period of

seven years

2.3. LITERATURE RELATED TO THE EFFECT OF PHYSICAL ACTIVITY ON

THE TYPE-2 DIABETES MELLITUS:

Obesity and type 2 diabetes have reached epidemic proportions in the United

States. It is well-established that increasing physical activity plays an important role in

reducing risk of obesity and diabetes (Hu FB, 2003). The hypertensive group had higher

34

body mass index (BMI) than the normotensive group (LU. FH., et.al, 2000). It revealed

that WHR was significantly correlated with TC (Ghosh A, et.al, 2004). The prevalence

of overweight in adults aged 18 to 64 years old was high in rural Deqing, which was

significantly associated with IFG and DM (Wei G, et.al, 2011).

Television (TV) watching, a major sedentary behavior in the United States, has

been associated with obesity. They hypothesized that prolonged TV watching may

increase risk for type 2 diabetes. A total of 1058 cases of type 2 diabetes were diagnosed

during 10 years (347 040 person-years) of follow-up. After adjustment for age, smoking,

alcohol use, and other covariates, the relative risks (RRs) for type 2 diabetes across

increasing quintiles of metabolic equivalent hours (MET-hours) per week were 1.00,

0.78, 0.65, 0.58, and 0.51 (P for trend, <.001). Time spent watching TV was significantly

associated with higher risk for diabetes. After adjustment for age, smoking, physical

activity levels, and other covariates, the RRs of diabetes across categories of average

hours spent watching TV per week (0-1, 2-10, 11-20, 21-40, and >40) were 1.00, 1.66,

1.64, 2.16, and 2.87, respectively (P for trend, <.001) (Hu FB, et.al, 2001, Sugiyama T,

et.al, 2008). Television viewing time, the predominant leisure-time sedentary behavior, is

associated with biomarkers of cardiometabolic risk (Dunstan DW, et.al, 2010, Hu FB,

2003). Prolonged TV viewing was associated with increased risk of type 2 diabetes,

cardiovascular disease, and all-cause mortality (Grøntved A, and Hu FB, et.al, 2011).

Regular physical activity and exercise are important components in the prevention

of diabetes. In addition to lowering blood glucose, exercise improves insulin action,

contributes to weight loss, and reduces several risk factors for cardiovascular disease.

Sedentary lifestyles have been linked to 23% of deaths from leading chronic diseases,

including heart disease and diabetes (Castaneda C, et.al, 2003). Regular physical

activity, are imperative to avoid complications, as well as polymedication, which is

associated with serious side-effects and drug-to-drug interactions. That regular and

moderate intensity physical exercise (training) is able, per se, to attenuate insulin

resistance and control glycaemia, dyslipidemia and blood pressure (Teixeira-Lemos E,

2011, Stewart KJ, 2004). Physical activity is inversely associated with coronary heart

disease morbidity and mortality (Rodriquez B.L, et.al, 2001). Exercise training also

reduces total and abdominal fat, which mediate improvements in insulin sensitivity and

35

blood pressure, and possibly, endothelial function (Stewart KJ, 2004, Arne Astrup,

2003).

2.4. LITERATURE RELATED TO THE EFFECT OF DIETARY HABITS ON

THE TYPE-2 DIABETES MELLITUS:

a.Hypoglycemic and hypocholestremic effect of whole grains and fiber:

Grains are a part of human diet for about 10,000 years. Grains are the most

important food sources of Indian population, due to this carbohydrate consumption

constitute approx. 60-70% of total food intake (Misra A, et.al, 2009, Anderson JW,

2008). Varieties of grains are available in India, and different grains form staple diets of

people in different part of the country. Whole grains are now recognized as an important

source of fiber and other nutrients like trace minerals and vitamins. Whole Grains have

shown to have a role in prevention and reducing the risk of type 2 diabetes, coronary

heart disease, cancer and obesity (Misra A, et.al, 2009, Anderson JW, 2008, Slavin J.,

2004, Zeigler JA, et.al, 1991).

Whole-grain foods are valuable sources of nutrients that are lacking in the

American diet, including dietary fiber, B vitamins, vitamin E, selenium, zinc, copper, and

magnesium. Despite recommendations to consume three servings of whole grains daily,

usual intake in Western countries is only about one serving/d. Whole-grain foods also

contain phytochemicals, such as phenolic compounds, that together with vitamins and

minerals play important roles in disease prevention (Slavin JL, et.al, 2001, Teresa T

Fung, 2002).

Dietary intake studies indicate that consumption of whole grains is far less than the

recommended intake of 3 servings a day, with an average daily intake of 1 or fewer

servings a day. A new whole-grains health claim, allowed in July 1999 by the Food and

Drug Administration, and inclusion of a whole-grain recommendation in the 2000

revision of the US Dietary Guidelines for Americans, should help increase whole-grain

consumption (Slavin JL, et.al, 2001). Whole grains have high concentrations of dietary

fibre, resistant starch, and oligosaccharides.

36

Whole-grain feeding studies reports improvements in

biomarkers with whole-grain consumption, such as weight loss,

blood-lipid improvement, and antioxidant protection. Although it

is difficult to separate the protective properties of whole grains

from dietary fibre and other components the disease protection

seen from whole grains in prospective epidemiological studies

far exceeds the protection from isolated nutrients and

phytochemicals in whole grains (Slavin J, 2004).

Whole grains have high concentrations of dietary fibre, resistant starch, and

oligosaccharides. Whole grains are rich in antioxidants including trace minerals and

phenolic compounds and these compounds have been linked to disease prevention. Other

protective compounds in whole grains include phytate, phyto-oestrogens such as lignan,

plant stanols and sterols, and vitamins and minerals. Whole-grain intake is protective

against cancer, CVD, diabetes, and obesity (Slavin J, 2004).

Oat bran in particular, is good source of B complex vitamins, protein, fat, minerals

besides heart healthy soluble fiber β-glucan. Different physiological effects of β-glucan

are related to its viscosity, attenuation of postprandial plasma glucose and insulin

responses, high transport of bile acids towards lower parts of the intestinal tract and high

excretion of bile acids thereby lowering of serum cholesterol levels (Masood sadiq Butt,

et.al, 2008). Davy and Melby 2003 reported that consumption of 20-35g/day of total

dietary fiber and at least 3 g/day of soluble fiber, necessary to observe a health benefit.

Composite flours containing wheat and legumes have proven practical uses and are

being utilized in many parts of the world to improve the nutritional and functional

properties of flour (Butt MS, et.al, 2007). Dietary fiber intake provides many health

benefits. Individuals with high intakes of dietary fiber appear to be at significantly lower

risk for developing obesity, and certain gastrointestinal diseases. Increased intake of

soluble fiber improves glycemia and insulin sensitivity in non-diabetic and diabetic

individuals (James W Anderson, et.al, 2009).

37

Multivariate logistic regression models demonstrated that the daily intake of 80 g of

fruits per 4184 kJ (1000 kcal) (OR 0•781; 95 % CI 0•617, 0•987; P = 0•039) or 50 g of

vegetables per 4184 kJ (1000 kcal) (OR 0•781; 95 % CI 0•618, 0•988; P = 0•040)

reduced the chance of the presence of HIGH mean BP (MBP ≥ 92 mmHg) by 22 % each,

adjusted for possible confounders. In conclusion, fruit and vegetables were the food

groups of the DASH diet associated with reduced BP values in patients with type-2

diabetes, and their consumption might play a protective role against increased BP values

(De Paula TP, et.al, 2012).

b. Hypoglycemic and hypocholesterolemic actions of barley:

It was found that the beneficial effect of consuming barley on the cardinal signs of

diabetes- hyperglycemia, polyphagia and polydypsia were attribute to the chromium and

not to any other constituent of the barley (Mahdi, et.al, 1991). It would be relevant to

point out that nearly five decades ago chromium was shown to potentiate the action of

insulin (Mertz, et.al, 1959). Chromium supplementation was shown to improve glucose

tolerance in glucose intolerant people (Anderson, et.al, 1991) and in type 2 diabetes

(Abraham, et.al, 1992, Bahijri, et.al, 2000). Barley and its various products have been

reported to possess preventive and therapeutic antidiabetic properties both in

experimental animals and clinical studies. Mungimeshi (prepared by boiling rice and

barley in the retio of 7:3) is a japanise staple food that find similarity with Indian food

preparation khichidi in a recent study (Joshi, et.al, 2007).

Barley intake has been shown to have beneficial effects on lipid metabolism (Li

et.al, 2003). Incorporating barley in a healthy diet may be effective in lowering plasma

total cholesterol and LDL cholesterol (Behall, et.al, 2004). Barley flavonoids (Lapcik,

et.al, 1988), mainly saponins (Klein, et.al, 1996), possess giant and diverse chemical

activities (glycosylation, oxidation, hydroxylation, methylation, and acylation reactions)

enabling them to act as potent toxins, detoxifiers and free radical scavengers. Hence,

barley flavonoids are strong antioxidants, contributing thus to protection against chronic

degenerative diseases (Candlish et.al, 1996, Jovanovic et.al, 2000).

38

Chromium is a trace metal essential for glucose and lipid metabolism (Mertz et.al,

1993), and chromium deficiency might contribute to insulin resistance, dyslipidemia,

atherosclerosis and type 2 diabetes mellitus (Mahdi et.al, 1996). Since chromium, unlike

most other minerals and trace elements, is distributed all over the barley grain i.e. in the

hull as well as the endosperm, and since the fiber and all other nutrients like iron, zinc,

manganese, copper and nickel except chromium are significantly reduced by

decortications prior to milling (Weaver, et.al, 1981).

According to Holtekjolen, et.al, (2008), if replacing 40 % of wheat flour with

barley flour made Breads, the incorporation of barley increased the antioxidant properties

of the breads compared to the control bread. Furthermore, these properties proved

depended on the variety of barley as well as the extraction rate of the flour. The amount

of free phenolics (TPC-S) decreased during the baking process, while the amount of

bound phenolics increased (TPC-IS). At the same time, the measured antioxidant

activities (FRAP-S and FRAP-IS) were relatively stable during the baking process. A

sensory evaluation showed differences in sensory attributes depending on the barley

variety, and there was a good consistency between the sensory evaluation and the amount

of phenolics.

For processed foods containing 4 g of β-glucan, the linear model predicted a

decrease in glycaemic response of 27 ± 3 mmol • min/l, and 76% of treatments

significantly reduced glycaemic response. Thus, intact grains as well as a variety of

processed oat and barley foods containing at least 4 g of β-glucan and 30-80 g available

carbohydrate can significantly reduce post-prandial blood glucose (Tosh SM, et.al,

2013). High dose barley beta-glucan supplement can improve glucose control when

added to a high-CHO starchy food, probably due to increased gastro-intestinal viscosity,

but not when added to a high-CHO beverage where rapid absorption combined with

decreased beta-glucan concentration and viscosity may obviate this mechanism (Poppitt

SD et.al, 2007). Pretreatment with barley and beer yeast enriched with chromium (BBCr)

caused a significant reduction of fasting glycaemia and glycaemia after glucose load.

Rosiglitazone and BBCr+R caused a significant reduction of glycaemia after adrenalin

load. Pretreatment with BBCr, R and BBCr+R prevented the onset of experimental

39

diabetes caused by alloxan, which was confirmed by histological analysis of pancreas

tissue (Cekić V, et.al, 2011).

c. Hypoglycemic effect of Bengal gram dal (Cicer arietinum):

Pulses, which are grown almost exclusively in south Asia, are popular complex

carbohydrates having in general relatively low G.I. and containing substantial protein and

fibre. Bengal gram (Channa dal) contains 64%carbohydrates with G.I. 33 to 42, protein

22%, fiber13.6gm/100gm and gives 327 kcal/100gm (Ghosh, 2005). Therefore these are

ideally suited as staples in Indian T2DM’s provided these could quantitatively replace

rice and wheat products in daily diet as the main energy sources. Local pulses have low

glycemic index & glycemic load hence could be safely used in the diet of diabetes

patients (Imran khan, et.al, 2008).

Recently it has been shown that diabetic subjects required less insulin or a

complete withdrawal of oral hypoglycemic agents when the unabsorabable carbohydrate

content in their diet was increased (Jenkins et.al, 1977, Miranda and Horwitz, 1978,

Kiehm et.al, 1976).

Galactomannans present in pulses are more viscous than fiber present in wheat and

rice. The viscosity of the dietary fiber has been shown to correlate positively with the

reduction in postprandial plasma glucose levels (Jenkins, et. al, 1978). Guar gum (a

galactomannan from cluster bean grown in India), the most viscous substance, was found

to be the most effective in decreasing postprandial glucose levels. The breath hydrogen

study with lactulose has shown that guar delays the mouth to cecum transit time

(Jenkins, et.al, 1978). This increase in transit time by guar may partly be due to delay in

gastric emptying (Leeds, et.al, 1979). Second, urinary xylose excretion over the 8-h

period remained similar whether xylose was given with or without guar gum indicating

the absence of malabsorption (Jenkins, et.al, 1978).

A premix, (67.5, 10, 10, 7.5,2.5, 2.5%), containing different proportion of locally

available ingredients namely wheat, bengal gram, dried peas, defatted soyflour, barley

and fenugreek seeds, was administered to 30 NIDDM subjects, equal number of both

40

sexes to find out the impact of administering indigenous fibre rich therapeutic premix on

blood glucose levels. The premix was given during breakfast in the form of chapattis for

90 days without disturbing the daily dietary pattern of the selected diabetic subjects. The

study revealed that there was a significant reduction in fasting and postprandial blood

glucose levels after 90 days of the premix supplementation (Kang, et.al, 2008).

d. Effects of dietary intake of soy protein and isoflavones and health benefit from

soya bean consumption:

Soyabean is regarded as equal in protein to animal foods. It has been found to be

excellent for a number of different conditions such as high hypertension, diabetes -

related diseases and many others (WHF, 2004). Soyabean produces high quality oil about

20% of its content and protein about 40% of the bean (Glami, 2002). The effect of 3-0

methyl – D- chiro inositol (D-pinitol), purified from soyabean was examined on the

postpradial blood glucose response in patient with type 2 diabetes mellitus. The

incremental area under the plasma glucose response curve for subjects who consumed

both pinitol and rice was low but pinitol had no apparent effect on postprandial insulin

levels. Therefore, soyabean –derived pinitol may be useful in controlling postprandial

increase in blood glucose in patient with type 2 diabetes (Kang & KIM, 2006).

Isoflavone compounds found in soyabean especially genistein may help to stay lean

by causing us to produce fewer and smaller fat cells (Naaz, et.al, 2003). Soyabean is

reputed to be able to lower total cholesterol levels by 30% (Desroches, et.al, 2004).

Food and Drugs Administrations (FDA) approving a health claim that 25g of

soyabean protein a day as part of diet low in saturated fat and cholesterol may reduce the

risk of heart diseases (Teixeira, et.al, 2000). The very high magnesium content of

soyabean can cause expansion of the peripheral blood vessels thereby helping to

decrease blood pressure to prevent hypertension (Lijuan, et.al, 2000). Soyabean in diets

has been found to have significant reductions in both diastolic and systolic blood pressure

(Sagara, et.al, 2004).

41

The protein and fibre in soyabeans can prevent rise in blood sugar level and help in

keeping blood sugar levels under control. Soyabean can be very beneficial to diabetic

patients particularly Non-Insulin Dependent Diabetes Mellitus (NIDDM). The proportion

of potassium to sodium (ratio 3/1 - 11/1) makes soyabean an ideal food for diabetes

mellitus patients (Lijuan, et.al, 2000). Soyabean has also been shown to promote serum

insulin production (Fukushima, et.al, 2000). Soyabean contains relatively high amounts

of glucosycermide, which may be the reason for the cancer-preventive effect of eating

soya foods (Symolon, et.al, 2004).

The soyabean is well heated to eliminate the anti-nutritional and undesirable

factors. The beany flavor of soyabean is reduced prior to incorporation into breakfast

cereals by only water blanching of alkali soaking and blanching (STS., 1987). Steaming

at 100°C inactivates the anti-nutritional factors in raw Soya flour, thus rendering a

maximum protein efficiency ratio. Soya milk should always be boiled for 5to 10 minutes

before consumption, so that no active inhibitors and no active haemagglutinins will be

present (Loo, 1978).

In a meta-analysis by Anderson et.al, (1995), in 38 controlled clinical trials, an

average consumption of 47 g of soy protein daily (primarily in subjects with

hyperlipidemia) significantly decreased the serum concentration of TC and low-density

lipoprotein cholesterol (LDL-C) and triglycerides without significantly affecting the

serum HDL-C concentration.

In an experiment by Malencic et.al, (2007), the contents and antioxidant ability of

various classes of phenolic compounds present in the seeds of twenty soybean hybrids

were evaluated. Total phenolics, tannins and proanthocyanidins were determined

spectrophotonmetrically, after extraction of seeds with 70% aqueous acetone. In addition,

the flavonoid contents were determined. The antioxidant activity of aqueous acetone

extracts was evaluated by the 1, 1-diphenyl-2-picrylhydrazyl (DPPH) free radical

scavenging activity assay. The highest contents of total phenolics were found in Serbian

cultivar 1511 and Chinese cultivar LN92-7369, which also displayed the highest total

antioxidant activity. Conversely, genotypes poor in phenolics also showed low levels of

42

DPPH-radical scavenging activity. The results suggested that besides protein and oil

contents, the phenolic contents should be also considered as an important characteristic

feature of soybean seeds, and as a potential selection criterion for antioxidant activity in

soybean.

Kochhar et.al, in (2009), performed an experiment, in which thirty non-insulin

dependendent diabetic females of 40-60 years were selected. After one-month control

period, 125 g of instant wheat meal (100 g of wheat flour and 25 g of soyabean flour in

4:1 ratio) (45 g in breakfast, 40 g in mid- morning and 40 g in evening tea) was given

daily to the selected subjects. This was given to all subjects on weekly basis for a period

of 2 months. Results in reduction of anthropometric parameters and blood pressure of

diabetic subjects and thus helped in reduction of secondary complications.

e. Hypoglycemic and hyocholestrmic effect of gaur gum:

Fasting blood glucose and hemoglobin A1c decreased significantly during the guar-

gum diet, whereas the diurnal glucose profile was unchanged. In addition, serum low-

density-lipoprotein (LDL) cholesterol decreased by 20% and the ratio of LDL cholesterol

to high-density-lipoprotein cholesterol by 28% during guar-gum therapy (Vuorinen-

Markkola H, et.al, 1992). Cholesterol and glucose lowering effects are most often

associated with gelling, mucilaginous, and viscous fibers such as guar gum, an edible

thickening agent. It has widespread applications in the food industry due to its ability to

hydrate without heating. The demand for guar gum is still growing rapidly because in

addition to its indispensable role in lowering serum cholesterol and glucose levels (Butt

MS, et.al, 2007). Various aspects of guar gum with special reference to its effectiveness

in reducing the cardiovascular disease risk, diabetes and weight loss programs is noticed

in this study (Butt MS, et.al, 2007).

f. Role of fat intake in type-2 diabetes:

43

Stone N. J. (1990) observed in his study that the chief factors in the diet which

raise cholesterol and low density lip-proteins cholesterol (LDL-C) are dietary cholesterol,

saturated fat, and excess calories leading to obesity.

Kris-Etherton P.M, et.al, 1999) in their study revealed that saturated fatty acids and

cholesterol raise the plasma cholesterol level whereas polyunsaturated fatty acids lower

it. The effects of other dietary constituents in particular, monounsaturated fatty acids,

soluble fiber and vegetarian diets favorably affect plasma lipid levels. Overweight and

obesity adversely affect plasma lipids. Omega-3 fatty acids are hypotriglyceridemia and

high carbohydrate diets low in saturated fatty acids is hypocholestrolemia.

Lower prevalence of impaired glucose tolerance and type 2 diabetes in

populations consuming large amounts of the n-3 long-chain polyunsaturated fatty acids

(n-3 LC-PUFAs) found mainly in fish Controlled clinical studies have shown that

consumption of n-3 LC-PUFAs has cardioprotective effects in persons with type 2

diabetes without adverse effects on glucose control and insulin activity.. (Joyce A, et.al,

2005)

2.5. LITERATURE RELATED TO THE ROLE OF GLYCEMIC INDEX IN

REDUCING THE RISK OF TYPE-2 DIABETES MELLITUS:

The glycemic index (GI) is a ranking of carbohydrates on a scale from 0 to 100

according to the extent to which they raise blood sugar levels after eating. Foods with a

high GI are those which are rapidly digested and absorbed and result in marked

fluctuations in blood sugar levels. Low-GI foods, by virtue of their slow digestion and

absorption, produce gradual rises in blood sugar and insulin levels, and have proven

benefits for health. Low GI diets have been shown to improve both glucose and lipid

levels in people with diabetes (type 1 and type 2). They have benefits for weight control

because they help control appetite and delay hunger. Low GI diets also reduce insulin

levels and insulin resistance (Johanna Burani, 2006). Carbohydrates that breakdown

quickly during digestion have a high GI because their B-glucose response is fast and

high. Carbohydrates that breakdown slowly have a low GI (Jenkins DJ, et.al, 2002).

Low glycemic index diets acutely induce a number of favourable effects, such as a rapid

44

weight loss decreasing of fasting glucose & insulin levels, reduction of circulating

triglyceride level & improvement of blood pressure (Radulian G. and Rusee E, 2009).

Meta-analysis of the relation between glycemic response to foods & health revealed

that unavailable CHO, independent of GI seems to have significant effect on health

outcome. Lower GI & GL diets are beneficial for health in persons with impaired glucose

metabolism (Hewlett J, 2008, Riccardi et.al, 2008). For healthy eating, particularly in

persons with diabetes, obesity and insulin resistance, foods with low GI are

recommended as they may help keep the euglycaemia and the normal spectrum of

lipoproteins (Brand-Miller JC, et.al, 2002, Heilbrann LK, et.al, 2002, Kabir M, et.al,

2002).

Both meal timing and GI affected glucose tolerance and insulin secretion.

Avoidance of large, high-GI meals in the evening may be particularly beneficial in

improving postprandial glucose profiles and may play a role in reducing the risk of type 2

diabetes; however, longer-term studies are needed to confirm this (Morgan LM, et.al,

2012).

A low-glycemic index (GI) diet may lower postprandial hyperglycemia and decrease the

risk for postabsorptive hypoglycemia in people with type 1 diabetes. Participants wore a

continuous blood glucose monitoring system and completed diet diaries on 2 days. On 1

day, participants consumed their usual meal; on another day, participants consumed low-

GI meals ad libidum. Order of the 2 days was counterbalanced. The mean GI was 34+/-6

for the low-GI day and 57+/-6 for the usual meal day (P<0.0001). During the low-GI day,

mean daytime blood glucose values (125+/-28 mg/dL [6.9+/-1.5 nmol/L] vs 185+/-58

mg/dL [10.3+/-3.2 nmol/L], P<0.001), blood glucose area above 180 mg/dL (4,486+/-

6,138 vs 26,707+/-25,038, P<0.006), and high blood glucose index (5.1+/-5.1 vs 13.6+/-

7.6, P<0.001) were lower compared to the usual mean day. During the low-GI day,

subjects consumed more fiber (24.5+/-12.3 g vs 14.5+/-6.1 g, P<0.007) and less fat

(45.7+/-12.2 g vs 76.8+/-32.4 g, P<0.005); however, there were no differences in energy,

carbohydrate, or protein intake. In this pilot study, a low-GI diet was associated with

improved diet quality and a reduction in hyperglycemia (Rovner AJ, et.al, 2009).

45

The beneficial effects of a low-glycaemic index (GI) meal on postprandial

glucose and insulin levels have been demonstrated in this study. Twenty-four normal-

weight and twenty-four overweight subjects, twelve with normal glucose tolerance

(NGT) and twelve with impaired glucose tolerance (IGT) in each group. Both test meals

were consumed once and the glucose reference twice. Blood glucose and insulin were

measured in the fasting state and over a 2 h period after each study meal, and TAG and

NEFA were measured in the fasting state and over a 5 h period. The glucose responses of

subjects with IGT differed significantly from those of subjects with NGT. The highest

insulin responses to both meals were observed in overweight subjects with IGT.

Physiological characteristics did not influence TAG or NEFA responses or the RGR of

the meals. The LGI meal resulted in lower glucose (P < 0·001) and insulin (P < 0·001)

responses, but higher TAG responses (P < 0·001), compared with the HGI meal. The GI

of the meals did not affect the NEFA responses. In conclusion, the LGI meal causes

lower glucose and insulin responses, but higher TAG responses, than the HGI meal. The

RGR of the meals does not differ between normal-weight and overweight subjects with

NGT or IGT (Perälä MM, et.al, 2011). The tight glycemic control can prevent and/or

delay the development of chronic complications of diabetes mellitus (DM) (Silva FM,

et.al, 2009).

Finding of the study demonstrated that the amount of

carbohydrate ingested accounted for 57-65% glucose response, while the glycemic index

of the CHO explained a similar amount (60%) of the variance. Together, the amount and

the glycemic index of CHO accounted for 90% of the total variability in blood glucose

response, indicating the cumulative effect of both factors and postprandial blood glucose

concentration (Wolever, 2003). Increased dietary GI and reduced fiber content were

positively associated with MetS, mainly due to breakfast intake, in patients with type 2

diabetes (Silva FM, et.al, 2011). Alternative low glycemic load diet can be effective in

glycemic control (Ziaee A, et.al, 2011).

46

1

2.6. LITERATURE RELATED TO THE ROLE OF DIETARY COUNSELING IN

MANAGEMENT OF TYPE-2 DIABETES MELLITUS:

Early identification of at-risk individuals using simple screening tools like the

Indian Diabetes Risk Score (IDRS) and appropriate lifestyle intervention would greatly

help in preventing or postponing the onset of diabetes and thus reducing the burden on

the community and the nation as a whole.

Lifestyle intervention in patients with impaired glucose tolerance results in an

impressive reduction in the conversion to overt diabetes (Hauner H, et.al, 2004). High

participant compliance and a positive attitude of providers make primary care a suitable

setting for diabetes prevention by lifestyle counselling. Results support a role for the

nurse practitioner as the key player in guiding lifestyle modification. Further research is

needed on strategies that could increase cost-effectiveness, such as more stringent criteria

for participant inclusion, group-counselling, more tailor-made counselling and integration

of screening and / or interventions for different disorders (Vermunt PW, et.al, 2012).

Counseling regarding diet and physical activity was based on the Nordic Nutrition

Recommendations. Increased intake of fatty fish and low glycemic index foods were

recommended. Compared with the control group, both intervention groups decreased

intake of saturated fatty acids (percent of energy), increased intake of dietary fiber, and

reduced average glycemic index of the diet. The ratio of n-6:n-3 fatty acids of the

erythrocyte membranes decreased, confirming increased intake of fatty fish. Body weight

decreased 1.7 kg (2.1%, P=.030) in group DE, and physical activity increased in the least-

active subjects (+70 min/week, P<.01 within group). Positive changes in lifestyle, blood

lipids and fasting insulin can be achieved and maintained in a non-diabetic population at

risk of type-2 diabetes (Brekke HK, 2003, Brekke HK, et.al, 2005, Melanson KJ, et.al,

2006). Nutrition counseling improved the knowledge of diabetics and control of diabetes

through diet. Significant decrease was observed in fasting blood glucose level of patients

(Renu Mogra, et.al, 2010, Srivastava et.al, 1998).

In a Randomized clinical trial, lasting four months it is clearly evident that

Patients who arrived more motivated were those who has the greatest reduction in the

values of body mass index, which decreased from 31.7 kg/m² (SD ± 3.9) to 30.9 kg/m²

47

(SD ± 3.8), reduction in waist circumference was 108.1 cm (SD ± 9.8) to 105.9 cm (SD ±

9.5). The statistically significant associations were in the correlation between body mass

index, blood glucose and triglycerides, reducing the consumption of whole milk,

increased consumption of whole grains and skimmed milk and between the increase in

vegetable intake and reducing triglycerides (Busnello FM, et.al, 2011).

Telephone counselling is also an effective way to implement behavioural

counselling to improve lifestyle habits in MetS patients especially type-2 diabetes

(Fappa E, 2012). Lifestyle changes that include a nutritionally balanced diet and

increased physical activity (PA) are effective intervention options for persons with

prediabetes who want to prevent progression to type 2 diabetes mellitus. Although

nutritional counselling is standard practice for patients in a clinical setting, an

individualized PA prescription, including recommendations on the type, frequency,

duration, and intensity, is much less likely to occur. This is surprising because lifestyle

modifications including a PA program are at least as effective in diabetes prevention as

any single pharmacological agent. The success of regular PA in improving glycemic

control in persons with either prediabetes or type 2 diabetes likely results from

adaptations that occur in several organs and tissues, including adipose, skeletal muscle,

liver, and pancreas (Burr JF, 2010).

After lifestyle-induced weight loss, improvements in oral glucose-induced insulin

secretion in older, obese, nondiabetic subjects seem to be largely dependent on improved

insulin sensitivity. However, in older obese diabetic patients, improved insulin secretion

is a consequence of elevated beta-cell function. We demonstrate for the first time that

changes in insulin secretion after lifestyle intervention may be mediated via alterations in

GIP secretion from intestinal K-cells (Solomon TP, 2010). Social support given by

general practitioners and practice nurses plays a crucial role for people with type 2

diabetes and is an additional component of social care. However there is a need for an

increased awareness by general practitioners and practice nurses about the influence

social support could have on the individual's diabetes management (Goetz K, et.al,

2012).

Diabetes risk factors could significantly be reduced by lifestyle counselling in

Dutch primary care. However, intervention effects above the effects attributable to usual

48

care were modest. Higher participant self-efficacy seemed to facilitate weight loss. Lack

of motivation or self-efficacy of professionals did not negatively influence participant

guidance (Milder IE, et.al, 2012). Educational short-term intensive intervention was

more effective than conventional treatment to achieve glycemic control. Results also

indicate that more appropriate fiber content in the diet contributes for better blood

glucose control in these patients (Carvalho FS, et.al, 2012).

India currently has more than 60 million people with Type 2 Diabetes Mellitus

(T2DM) and this is predicted to increase by nearly two-thirds by 2030. While

management of those with T2DM is important, preventing or delaying the onset of the

disease, especially in those individuals at 'high risk' of developing T2DM, is urgently

needed, particularly in resource-constrained settings. This paper describes the protocol

for a cluster randomized controlled trial of a peer-led lifestyle intervention program to

prevent diabetes in Kerala. Data collection is conducted in two steps. Step 1 (Home

screening): Participants aged 30--60 years are administered a screening questionnaire.

Those having no history of T2DM and other chronic illnesses with an Indian Diabetes

Risk Score value of >=60 are invited to attend a mobile clinic (Step 2). At the mobile

clinic, participants complete questionnaires, undergo physical measurements, and provide

blood samples for biochemical analysis. Results from this trial will contribute to

improved policy and practice regarding lifestyle intervention programs to prevent

diabetes in India (Sathish T, et.al, 2013).

There is now strong evidence from randomised, controlled trials that lifestyle

interventions incorporating diet and physical activity can prevent Type 2 diabetes in high

risk individuals from different ethnic backgrounds (Pan XR, et al 1997, Tuomilehto J,

et.al, 2001, Ramachandran A, 2006) and that intensive lifestyle interventions are rated

as very cost-effective (Li G Zhang, P et.al, 2008). The risk of Type 2 diabetes is

reduced by 28 to 59 per cent after implementation of lifestyle change (Walker KZ, et.al,

2010), and there is some evidence of a legacy effect, with three trials reporting lower

incidences of Type 2 diabetes at 7 to 20 years follow-up beyond the planned intervention

period (Lindstrom J, et.al, 2006, Knowler WC, et.al, 2009). The main components of

these lifestyle interventions included weight loss, reduction in fat.

49