Obesity - a major public health challenge
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Transcript of Obesity - a major public health challenge
Obesity - a major public health challenge
W Philip T James MD,DSc, FRCP
London School of Hygiene and Tropical Medicine President, International Association for the Study of Obesity
Central obesity and insulin resistance: South Asian susceptibility: probably applies to Middle East &
Mexico
McKeigue et al. Lancet, 1991, 337: 382
Central obesity and insulin resistance in South Asians
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From Mckeigue et al. Lancet, 1991, 337: 382
South Asian
European
Diabetes prevalence %
Waist / hip ratio
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Smoking
High blood pressure
Overweight & obesityHigh cholesterol
Alcohol usePhysical inactivity
Low fruit & veg. intake
Illicit drug useUnsafe sex
Iron deficiency anemia
Attributable disease burden (% regional DALYs; total 149 million)
The top risk factors underlying the disease burdenof high income countries (all preventable)
WHO / World Bank. Global Burden of Disease. Lopez et al., 2006.
The current obesity dilemma
Obesity is a normal "passive" biological response to our changed physical and food environment
Some children/adults are more susceptible for genetic, social and economic reasons
Overwhelming environmental impact reflects outcome of normal industrial development
Obesity reflects failure of the free market
UK Government report Oct. 2007 Provided on a non - political basis by the Chief Scientist
Predicted diabetes health care costs in England with different prevention strategies
Annual costs £ Millions
BMI All ages Cap at 30;50% effective
20+yrs: BMI -4 units
No Action
Childhood prevention
6-10 yrs
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Foresight Report on Obesity.2007. http://www.foresight.gov.uk/Obesity/14.pdf
The costs of different degrees of excess weight in the USA
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Arterburn D et al. Impact of morbid obesity on medical expenditure in adults. IJO, 2005; 29: 334-339.
Why the obesity pandemic?An OECD 2010 perspective
• “ The mass production of food over time has changed both the quality and availability of food
• Falling relative food prices contributed up to 40% of the increase in BMI in the US 1976-1994….
• Convenience also played a major role, in combination with falling prices, with the spread and concentration of fast food restaurants…..
• The use of increasingly sophisticated marketing techniques is naturally associated with an increase in the supply of food….
• These effects are consistent with the patterns observed in the distribution of obesity among population groups, with more vulnerable individuals and families and those whose time available for meal preparation and cooking has become more limited being more exposed to the influence of supply-side changes.”
Economic development and falling food needs
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Car UseMechanical aids
TVComputers
Energy needs
US Intakes
UK Intakes
Increasing obesity
Economic development and ageing
The keys to success in the food business and in obesity and chronic disease (NCDs)
prevention
• Price
• Availability
• Marketing
The natural history of childhood overweight/obesity using IOTF cut-offs in Australia over the last century and regional global increases
Wang and Lobstein, IOTF, Int J Ped Ob 2006.
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All data
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Recent surveys Projected 2006 Projected 2010
Americas (1988-2002)Eastern Med (1992-2001)Europe (1992-2003)South East Asia (1997-2002)West Pacific (1993-2000)
e.g. Japan
e.g. India
%
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e.g. S.Arabia e.g. UK
Global total now: obese 74 mil. +overwt. 287 mil.
Norton K et al, Int J Ped Ob 2006
Australia
Functional Brain Maturation Curve implying that protecting adolescents from marketing is a critical
issue: marketing bans should apply up to 18 yrs of age
Dosenbach et al . Prediction of individual brain maturity using fMRI. Science 2010;329: 1358-1361
"Blood oxygen level–dependent time courses were generated for 160 regions of interest derived from a series of meta-analyses of task-related fMRI studies that cover much of the brain"
Snack Foods are everywhere Car washes Book stores Hardware stores (Home Depot) Gas stations Office buildings (vending machines) Health clubs/gyms Video stores Car repair shops
End of aisle display increases sales 2-5 fold
1. Major parallels between addiction characteristics and conditioned desire for hyperpalatable foods: food cues and consumption can activate neurocircuitary (meso-cortical- limbic pathways) implicated with addiction
2. Humans: reduced dopamine receptor availability/striatal dysfuntion associated with obesity and weight gain: craving, persistent eating despite consequences and uncontrolled consumption seen in both.
3. Genetic and environmnetal factors well accepted in addiction; also in obesity
4. Blaming the individual first was immediate reaction to addiction as in obesity; individual treatment limits blame + both cost-effective.
5. Policy initatives crucial to reducting burden of both addiction and obesity
Addiction.2011; 106: 1208-1212
Obesity: parallels with addiction• Personal responsibility always applied by public,
politicians and the relevant industries to: a) Tobacco b) Alcohol c) Obesity
• Policy developments delayed by emphasis on individual strategies for treatment + prevention
• Refocus on addictive properties leads to bold public health measures: a) Taxation b) limiting access c) banning marketingResults: dramatic improvement to personal
efforts when add policies - but only if properly implemented
Adapted from Gearhardt et al Addiction 2011;106 1208-1212
Diabetes prevention on a national scale in Finland
Incidence of DM Normal GT: 2.0 % men, 1.2% women Impaired FG: 13.5% men, 7.4% women
Impaired GT: 16.1% men, 11.3% women
Incidence DM in obese without diabetes:2.5-4.9 % weight loss: 28% less diabetes
>5% weight loss: 69% less diabetesBut
>2.5% weight gain: 10% more diabetes
Saaristo et al . One year follow–up of the Finnish National Diabetes Prevention Program (FIN-D2D). Diabetes Care 2010;33: 2146-2151
Local opportunities: obvious immediate needs• Baby friendly hospitals?• Breast feeding duration? Facilities?• Nursery school policies for food and physical
activity?• Food control in all schools? School
water/banned soft drinks? • Measurement of children in school - policies?
Parental notification? Advice• School policies on education: Academies?
Importance of parental pressure groups • Focus on young girls and pre-pregnancy
weight?
Local opportunities: immediate needs
• Food in all local government funded facilities exclusively high nutritional standards? Offices, police, colleges?
• State of obesity of publicly funded workers? Work- site initiatives.
• Diabetes prevention policies? Evidence of benefit overwhelming
• GP groups - who specialises in obesity? Clear evidence of benefit. Links to weight control groups?
• Retirees: activity and dietary policies?
Organisational strategy• Public health leaders : bring in to the centre of
strategy on Council business as in pre-1984.• Think radically but move progressively.• Watch conflicts of interest: brilliant counter-
marketing and policy manipulation by industrial interests
• Use public meetings and local media to change cultural attitudes - see smoking, seat belt, school food policies.
• Industry brainwashing : Remember parents and young people already persuaded to focus on "choice" and 24hr availability of food, drinks and entertainment
Local opportunities: progressive strategies: make Cornwall the county of new initiatives
• Physical activity: progressive policies on restricted car use with pedestrian and cycle promotion.
• Council devised progressive reduction in salt, sugar and fat in standard recipes of canteens, restaurants
• Take Bloomberg New York approach to food for the public - Calorie labelling of menus; make a feature of Cornish quality products only if nutritionally comply
• Move towards Finnish approach to vegetables in cost of main meals and salad bar "free"
• Local bakers - salt reduction• Restricting vending machines, fast food outlet density• Council devised and organised walking groups for huge health
burden of middle aged and elderly patients identified by GPs