why weight is important in cancer | dr martin wiseman

Martin Wiseman

World Cancer Research Fund

International

University of Southampton, UK

OBESITY IN THE DEVELOPMENT AND

PROGRESSION OF CANCER

Obesity and overweight in Scotland

1995 - 2010

Scottish Health Survey 2010

Obesity and overweight in Scotland

1995 - 2010

Scottish Health Survey 2010

29%

64%

Prevalence of obesity among adultsHealth Survey for England 1993-2011 (3-year average)

0%

5%

10%

15%

20%

25%

30%

Pre

vale

nce

of o

be

sity

Women

Men

24%

Prevalence of overweight among adultsHealth Survey for England 1993-2011 (3-year average)

30%

35%

40%

45%

50%

55%

60%

65%

70%

Pre

vale

nce

of o

verw

eigh

t

Men

Women

58-66%

Prevalence of obesityBMI>30 16-64y

OPCS 1980

NDNS 1987- 2000

HSE 1991-1998

Obesity in Scotland - 2010

Scottish Health Survey 2010

Adult obesity prevalence by ageHealth Survey for England 2009-2011

9.4%

16.6%

23.1%

33.7% 33.4%

29.3%

25.8%

13.2%

19.3%

25.0%

29.3%31.0%

33.2%

28.2%

0%

5%

10%

15%

20%

25%

30%

35%

16-24 25-34 35-44 45-54 55-64 65-74 75+

Pre

vale

nce

of o

bes

ity

Men Women

Obesity in Scotland - 2010

Scottish Health Survey 2010

Obesity costs

1. NHS: £5.1 billion (Scarborough 2011)

2. Economy: £16 billion (Foresight 2007)

3. Economy projected to 2050

£50 billion (Foresight

2007)

The most rigorous, systematic, comprehensive and

authoritative reviews of the accumulated evidence in

the field of food, nutrition, physical activity and

cancer

Nutrition and cancer

1. OBESITY– BREAST (Postmenopause), COLORECTUM, ENDOMETRIUM,

OESOPHAGUS, PANCREAS, GALLBLADDER, KIDNEY

2. PHYSICAL ACTIVITY– COLON, BREAST, OBESITY

3. RED AND PROCESSED MEAT– COLORECTAL

4. PLANT FOODS– MOUTH, PHARYNX, LARYNX, OESOPHAGUS, STOMACH,

COLORECTAL (dietary fibre), LUNG, OBESITY

5. ALCOHOL– MOUTH, PHARYNX, LARYNX, COLORECTUM, LIVER

6. SALT– STOMACH

7. BREASTFEEDING– BREAST, EXCESS WEIGHT GAIN (CHILD)

The Panel emphasises the

importance of not smoking and of

avoiding exposure to tobacco smoke

The Panel emphasises the

importance of not smoking and of

avoiding exposure to tobacco smoke

Nutrition and cancer

1. OBESITY– BREAST (Postmenopause), COLORECTUM, ENDOMETRIUM,

OESOPHAGUS, PANCREAS, GALLBLADDER, KIDNEY

2. PHYSICAL ACTIVITY– COLON, BREAST, ENDOMETRIUM, OBESITY

3. RED AND PROCESSED MEAT– COLORECTAL

4. PLANT FOODS– MOUTH, PHARYNX, LARYNX, OESOPHAGUS, STOMACH,

COLORECTAL (dietary fibre), LUNG, OBESITY

5. ALCOHOL– MOUTH, PHARYNX, LARYNX, COLORECTUM, LIVER

6. SALT– STOMACH

7. BREASTFEEDING– BREAST, EXCESS WEIGHT GAIN (CHILD)

Obesity and cancer

BREAST (Postmenopause)

COLON and RECTUM

ENDOMETRIUM

OESOPHAGUS

PANCREAS

GALLBLADDER

KIDNEY

Effects of products of adipocytes

Adipose

tissue

↑ IL-6

↓ Adiponectin

↑ Leptin

↑ TNFα

↑ Adipsin

(Complement D)

↑ Plasminogen

activator inhibitor-1

(PAI-1)

↑ Resistin

↑ FFA

↑ Insulin

↑ Angiotensinogen↑ Lipoprotein lipase

↑ Lactate

Inflammation

Type

2 diabetes

Hypertension

Atherogenic

dyslipidaemia

ThrombosisAtherosclerosis

Lyon 2003; Trayhurn et al 2004; Eckel et al 2005

Elevated oestrogen

Aromatase

Obesity and cancer

Mechanisms1. Insulin resistance

• abnormal insulin/IGF axis

• excess growth factors

2. Inflammation• promotes oncogenic genetic signature

• increases proliferation, angiogenesis

• reduces apoptosis

3. Excess oestrogen• promotes proliferation and cancer in sensitive

tissues

Around one third of the commonest

cancers estimated avoidable

through appropriate food, nutrition

and physical activity

Obesity and cancer

progression

Expert US WORKSHOP 2011

Breast cancer• Normal weight at diagnosis associated with better outcomes

• Higher (and low) BMI at diagnosis associated with greater recurrence and death.

• Obesity: 30% increase in mortality

40+% increase in metastases after 10 y

• Importance of physical activity

Obesity and cancer

progression

US Expert WORKSHOP 2011

Prostate cancer• Sparse and conflicting evidence

Colon cancer• Limited early evidence only

Cancer incidence by weight loss tertile

SOS

Obesity and cancer

progression

Summary

Obesity is an adverse prognostic factor, but the impact of weight loss on outcome is less clear.

Nevertheless, weight management in cancer survivors is important, both for quality of life and for co-morbidities.

0

1

2

3

4

5

6

7

8

Fatness, Fitness & Cardiovascular Disease

Mortality

Lean

<16.7%

Rel

ativ

e R

isk

of

CV

D M

ort

alit

y

Body Fat Category (% Fat)

Lee et al. Am J Clin Nutr 1999;69:373.

Normal

16.7%-24.9%

Obese

>25%

Fit

Unfit

Is It Possible For Obese To Be Fit?

Normal Overwt Obese Normal Overwt Obese

0

2500

5000

7500

10000

12500

15000

17500

20000

Unfit

Fit

Men Women

Nu

mb

ers

Continuous Update Project

(CUP)• Keep evidence, conclusions and

recommendations updated into the future

• Working with team at ICL

• Same principles:

- Systematically review evidence

- Meta analysis

- Panel of experts-draw conclusions

-make recommendations

Conclusions1. With smoking, food, nutrition, body fatness and

physical activity are the most important factors affecting cancer risk

2. About 20% of the commonest cancers in high income countries could be prevented by maintaining a healthy body weight

3. There is strong evidence that being a healthy weight is linked to improved outcome in breast cancer survivors

4. Evidence for an effect in survivors of prostate and colon cancers is generally less compelling

5. Physical activity is also important –

– but separate

http://www.dietandcancerreport.org