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NutritionNutrition

•• Human NutritionHuman Nutrition - The science of food, the nutrients and other substances contained therein, their action, interaction, and balance in relation to health and disease

•• Normal NutritionNormal Nutrition - caloric and nutrient requirements throughout the life cycle and for specific populations

•• Clinical NutritionClinical Nutrition - nutrition intervention aimed at the treatment or prevention of disease or illness

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NutrientsNutrients

• Macronutrients– Carbohydrates– Proteins– Fats

• Micronutrients– Vitamins – Minerals

• Others– Fiber, water

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VitaminsVitamins

•• Organic substances essential for Organic substances essential for normal cell function, growth and normal cell function, growth and developmentdevelopment

•• There are 13 essential vitaminsThere are 13 essential vitamins•• They are grouped into 2 categories: They are grouped into 2 categories:

fatfat--soluble and watersoluble and water--solublesoluble•• Present in various foods and are Present in various foods and are

available as dietary supplementsavailable as dietary supplements

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Vitamin Sources & FunctionsVitamin Sources & FunctionsVitaminVitamin SourcesSources FunctionFunction

AA Cod liver oil, dairy products, sweet potatoes, carrots, leafy vegetables, and fortified foods such as breakfast

Needed for good eyesight and normal functioning of the immune system

BB--1 1 (Thiamine)(Thiamine)

Enriched, fortified, or whole-grain products, such as bread, pasta, and cereals. Helps the body process carbohydrates.

Helps the body process carbohydrates

BB--22 Organ meats, breads, fortified cereals, almonds, asparagus, cooked eggs, dark meat chicken, and cooked beef

Used in many body processes, such as converting food into energy. It also participates in the metabolism of many drugs and helps in the production of red blood cells

BB--3 (Niacin)3 (Niacin)Light-meat chicken, tuna, salmon, turkey, enriched flour, peanuts, and fortified cereals

Aids in digestion and converting food into energy. Also used by the body to help make cholesterol

BB--66 Fortified cereals, fortified soy-based meat substitutes, baked potatoes with skin, bananas, light-meat chicken and turkey, eggs, and spinach

Vital for a healthy nervous system. Helps the body break down proteins. Helps the body break down stored sugar

BB--1212 Beef, clams, mussels, crabs, salmon, poultry, soybeans, and fortified foods

Needed for creating red blood cells

Reference: http://www.webmd.com/diet/vitamin-mineral-sources (2010)

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Vitamin Sources & FunctionsVitamin Sources & FunctionsVitaminVitamin SourcesSources FunctionFunction

C (Ascorbic

acid)

Citrus fruits, red berries, tomatoes, potatoes, broccoli, cauliflower, brusselssprouts, red and green bell peppers, cabbage, and spinach

Helps promote a healthy immune system and is required to help make collagen, which holds cells together. It is also required for making chemical messengers in the brain

D Fortified milk, cheese, and cereals; egg yolks; salmon; and sunlight

Needed to process calcium and maintain bone health

E Leafy green vegetables, almonds, hazelnuts, and vegetable oils like sunflower, canola, and soybean

Functions as an antioxidant

Folate(Folic acid)

Fortified cereals and grain products; lima, lentil, and garbanzo beans; and dark leafy vegetable

Vital for cell development, prevents birth defects, promotes heart health, and helps red blood cells form

K Leafy green vegetables like parsley, chard, and kale; olive, canola, and soybean oils; and broccoli

Helps clot blood and maintains bone health

Reference: http://www.webmd.com/diet/vitamin-mineral-sources (2010)

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1. Observed food intakes by healthy individuals expressed as recommended dietary allowance; intake meeting dietary requirements of 95% of individuals (RDA)

2. Genetic, developmental, lifestyle, environmental, normal aging, and pathologic conditions for any given individual, which may vary greatly from the RDA

Nutrient Requirement is based on:Nutrient Requirement is based on:

Am J Clin Nutr 2000;72(suppl):507S–11S.

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Limitation of RDALimitation of RDA

• It is based on normal distribution, thus it may not reflect the need of a certain segment of the population

RDA

Intake needed to meet requirement

Num

ber o

f per

sons

Average requirement

2SDs5% of population

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Food label showing % Daily Value Food label showing % Daily Value

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• Nutrient in the diet may be inadequate due to low food intake

• A person’s intake of nutrients may be dependent on RDA, but new scientific data indicates that such recommendations underestimate individual requirements

• Special conditions at a certain point in the person’s life cause requirements to change without corresponding changes in diet.

Some reasons behind the use of Some reasons behind the use of individualized nutrient requirement:individualized nutrient requirement:

Nutrients in the diet may be

inadequate due to low food intake

REASON 1REASON 1

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UndernutritionUndernutrition is still a problemis still a problem……

•• More than 1.02 B More than 1.02 B hungry people hungry people worldwideworldwide

•• Neglect of Neglect of agricultureagriculture

•• Worldwide Worldwide economic crisiseconomic crisis

•• Significant Significant increase in food increase in food pricesprices

FAO Report (2009)

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One out of 3 people in One out of 3 people in developing countries are developing countries are affected by vitamin and affected by vitamin and mineral deficiencies, mineral deficiencies, according to WHO (2009)according to WHO (2009)–– Vitamin AVitamin A–– IronIron–– IodineIodine

Vitamin and mineral deficiencies existVitamin and mineral deficiencies exist……

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•• In 2002In 2002--03, a study reported that 03, a study reported that Americans have inadequate intake of:Americans have inadequate intake of:–– Vitamin E (93%)Vitamin E (93%)–– Magnesium (56%)Magnesium (56%)–– Vitamin A (44%)Vitamin A (44%)–– Vitamin C (31%)Vitamin C (31%)

What We Eat in America Report What We Eat in America Report –– USDA 2005USDA 2005

Countries abundant in food have not Countries abundant in food have not eradicated vitamin & mineral deficiencieseradicated vitamin & mineral deficiencies……

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A study of fast food A study of fast food restaurant use among restaurant use among

4746 adolescents:4746 adolescents:associations with associations with

nutrient intake, food nutrient intake, food choices andchoices and

behavioral and behavioral and psychosocial variablespsychosocial variables

revealed thatrevealed that……

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• Positively associated with intake of total energy, percent energy from fat, daily servings of soft drinks, cheeseburgers, french fries and pizza

• Inversely associated with daily servings of fruit, vegetables and milk

• Positively associated with student employment, television viewing, home availability of unhealthy foods, and perceived barriers to healthy eating

Frequency of fast food restaurant use wasFrequency of fast food restaurant use was……

International Journal of Obesity (2001) 25, 1823–1833

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•• Vitamin B6 for women > 50 Vitamin B6 for women > 50 y/oy/o•• Zinc for males and females >70 Zinc for males and females >70 y/oy/o•• Only about half of women aged 9Only about half of women aged 9--

18 18 y/oy/o has adequate intake of has adequate intake of phosphorusphosphorus

Inadequate intake of nutrients among Inadequate intake of nutrients among specific segments of population did specific segments of population did

existexist……

What We Eat in America Report – USDA 2005

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Fruit & vegetable consumption in many Fruit & vegetable consumption in many countries has decreasedcountries has decreased……

• Food consumption surveys showed low consumption of fruits and vegetables in many regions of the developing world.

• At present, only a small and negligible minority of the world’s population consumes the generally recommended high average intake of fruits and vegetables. – In 1998, only 6 of the 14 WHO regions had an

availability of fruits and vegetables equal to or greater than the earlier recommended intake of 400 g per capita per day.

World Health Organization Technical Report Series No. 916 (2003)

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AlsoAlso……•• The stress resulting from demanding jobs The stress resulting from demanding jobs

and having Type A personality are and having Type A personality are contributory to the lack of attention given contributory to the lack of attention given to the food being taken in. to the food being taken in.

•• The proliferation of fast food chains and The proliferation of fast food chains and readyready--toto--cook quick meals becomes an cook quick meals becomes an easy alternative to welleasy alternative to well--thought of meals.thought of meals.

•• Meal planning belongs to the health Meal planning belongs to the health conscious few. conscious few.

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A person’s intake of nutrients meet RDA,

but new scientific data indicates that

such underestimate individual

requirements

REASON 2REASON 2

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ExamplesExamples• Need for increased folic

supplementation for women of reproductive age starting three months prior to conception to prevent NTD and other congenital anomalies.

• High incidence of Vitamin D deficiency among pregnant women in Australia & NZ. Higher requirement for those with limited sun exposure.

J Obstet Gynaecol Can 2007;29(12):1003–1013

RANZCOG College Statement: C-Obs 25 (2008)

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There are special conditions at

different points in life requiring amounts of

nutrients higher than RDA

REASON 3REASON 3

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Genetic FactorGenetic Factor• Hyperhomocysteinaemia is the commonest of

the thrombophilias with approximately 1.5% of the population being homozygous for the MTHFR mutation and 25% heterozygous. The thrombophilic tendency is minimised by an adequacy of folate, riboflavin, B6 and B12.

Royal Australian and New Zealand College of Obstetricians and Gynecologists College Statement: C-Obs 25 (2008)

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Developmental FactorsDevelopmental Factors

•• InfancyInfancy•• ChildhoodChildhood•• AdolescenceAdolescence•• PregnancyPregnancy•• LactationLactation•• AgingAging

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ExampleExample

• Adolescents, particularly girls, are especially vulnerable to iron deficiency due to low intake and absorption of iron, and increased iron requirements for growth and replacement of menstrual blood losses. Anemia can be associated with other nutrient deficiencies (folic acid, vitamin A, B 12)Adolescent Nutrition: A Review of the Situation in Selected South-East Asian Countries (2001)

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Lifestyle ChoicesLifestyle Choices• Reduced intake of dietary fat

– Reduces absorption of fat-soluble vitamins• Engagement in sports

– High oxygen demand on blood requiring B vitamins– Need for preventing oxidative damage to cellular and

subcellular structure and function during exercise requiring antioxidant vitamins

• Smoking– Oxidative damage and depletion of endogenous

antioxidants

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Lifestyle ChoicesLifestyle Choices• Vegetarianism

– Vegans on fad require Vitamin B12 usually lacking in their diet

• Obesity– Imbalance in nutrient intake

• Excessive Coffee drinking– Calcium depletion

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AgingAging• Major structural, functional and

metabolic changes– Decreased stomach acid and intestinal blood

flow affecting breakdown & absorption of Vitamin B12

– Decrease in hormone production, etc.– Modification of vitamin requirements

• Postmenopausal women– Presence of multiple diseases– Intake of multiple medicines– Cognitive decline

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Pathologic Pathologic

NutrientNutrient Condition/ DiseaseCondition/ DiseaseVitamin D Multiple sclerosis, osteoporosis,

cardiovascular conditionsMultivitamins HIV survival

Vitamin B-6, Folate, and Vitamin B-12

Symptoms of depression

Folic Acid Several forms of cancer -colorectum, breast, ovary, pancreas, brain, lung and cervix

Vitamin A Pulmonary tuberculosis

Various vitamins Surgery, injury, recovery, rehabilitation

* In addition to various deficiency conditions emanating from inadequate intake and disturbed metabolism

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Is there really a Is there really a need for vitamin need for vitamin

supplementation?supplementation?

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“A supplement has benefit only when the normal intake of a bioavailable form of a nutrient is lower than the amount that would provide maximum benefit as judged from all biological perspectives.

To be efficacious, dietary supplements must either provide a nutrient that is normally undersupplied to cells or exert a pharmacologic effect on cellular processes.” (Steven Seizel 2000)

Am J Clin Nutr 2000;72(suppl):507S–11S.

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“Metabolic, environmental, and genetic factors can make individual nutrient requirements differ from the estimated needs calculated from population-based data.”

Am J Clin Nutr 2000;72(suppl):507S–11S.

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Is intake sufficient?Is intake sufficient?

Optimal Function

Risk reduction

Pharmacologic

Life Cycle

Environment

Lifestyle

Can intake be achieved from Food?

Use Supplement

NONO

Is there a scientific basis to increase intake?

AN APPROACH TO DIETARY SUPPLEMENTATION

Adapted from Seizel, S. Am J Clin Nutr 2000;72(suppl):507S–11S.

Higher Requirement?Higher Requirement?

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ConclusionsConclusions• Food is still the best source of vitamins and

other nutrients• There are factors which affect nutrient

requirement of an individual • There are valid reasons for vitamin

supplements as long as they are backed up by scientific evidences

• Too much vitamin intake is equally as dangerous as lack of intake

• Pharmacists have a role to play in the use of vitamin supplements

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