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Sugar, addiction and obesity Simon Thornley Public Health Physician/ PTF/ PhD student University of Auckland

Sugar, addiction and obesity

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Simon Thornley Public Health Physician/ PTF/ PhD student University of Auckland. Sugar, addiction and obesity. Summary. What is science? Is there an obesity epidemic? A brief history of nutrition I get involved… Food addiction What next?. Dairy photo. Museum photo…. What is science?. - PowerPoint PPT Presentation

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Sugar, addiction and obesitySimon Thornley

Public Health Physician/ PTF/ PhD studentUniversity of Auckland

Summary What is science? Is there an obesity epidemic? A brief history of nutrition I get involved… Food addiction What next?

Dairy photo

Museum photo…

What is science? “In God we trust, all others must bring data”

William Edwards Deming

“First establish the facts, then seek to explain them” Aristotle

Anarchistic Consensus not useful Hypothesis and argument Disproving useful, not proof. Probabilities over absolutes

The obesity epidemic Where has it occurred? Over what time period? Explanations? What have we been told to eat? Is it working?

Is there an obesity epidemic?

What happened in the 1960s? Diet-Heart Hypothesis Heart disease caused by saturated fat Response: reduce fat (↑sugar or carb.) Cheap sugar (HFCS) American Heart Assoc.– spread to other

English speaking countriesTaubes G. The Diet Delusion. New York: Vermilion; 2007.

Laws of thermodynamics A – B = C A = Energy in (food) B = Energy out (burned, exercise/basal

metabolic rate) C = Energy stored (as fat) δA - environmental change (Coke ads/vending

machines)

MY STORY

My thoughts on obesity

Medical trainingTraditional Nutritional theory - Energy density

Public HealthUnderstanding addiction

ResearchSimilarities between obesity and smoking

ResearchCritique of energy densityFocus on sugar

1994 2005 2007 2011

Tobacco withdrawal

Symptoms in detailSigns and symptoms

Duration (weeks)

Proportion(%)

Irritability < 4 50

Depression < 4 60

Restlessness < 4 60

Poor concentration <2 60

Increased appetite >10 70

Sleep disturbance <1 25

Urges to smoke >2 70

Mouth ulcers <4 40

Constipation >4 17

Addiction? Automatic behaviour

Rational behavioure.g. Planning,

Picking up children after work

Addiction – Automatic,

withdrawal, can’t stop, causes harm

e.g. heroine

Automatic behaviour?

e.g. breathing

CortexMid brain/brain stem

Negative re-inforcement

Withdrawaldiscomfort

Puffcigarette

WithdrawalreliefMore

puffs

Nicotine metabolised

How to profit from tobacco...?

Nicotine delivery

Royal College of Physicians, Nicotine in Britain, 2000

FOOD ADDICTION?

Carbohydrate?

Eating and addiction? “Atkins Diet” An executive who had tried obesity surgery,

laxatives, diets, everything…

“Often I would shake until I could put some sugar in my mouth”

“I had an hour’s drive from my office to my home, and I knew every restaurant, every candy machine and every soft drink dispenser along the whole route.”

What about glucose? Glycemic index very similar for glucose Is carbohydrate the same as nicotine? Is low GI a way out like nicotine patch or

gum?

Bread - White vs Vogel’s

Glucose: glycemic index?

What about sugar? Sugar is actually moderate GI

WHAT DO WE KNOW ABOUT SUGAR?

BIG SUGARBrian Mckenna

What does the good book say? “It is not yet clear whether any single

attribute of the Western way of life is particularly important in increasing the risk of diabetes. Excess sucrose has largely been exonerated as an important dietary factor in the aetiology of type 2 diabetes...”

J. I. Mann and A. S. Truswell Diseases of overnourished societies and the need for dietary change: in the Oxford

Textbook of Medicine, 4th Edition.

Sugar – traditional views 30% increase over last 30 yearsPopkin BM, Nielsen SJ. The sweetening of the world's diet. Obesity Research 2003;11(11):1325-32.

“empty calorie”Nestle M. Soft drink "pouring rights": marketing empty calories to children. Public Health Reports

2000;115(4):308-19.

Sucrose and other free sugars restricted to up to <15% of total caloric intake, due to excess energy and dental caries.

Food and nutrition guidelines (Ministry of Health) 2003.

Fructose not mentioned

Average NZ consumption: UN statistics (‘07)– 153g/day

= 38 teaspoons/ day 17% of total energy Compare – 1961 – 33 teaspoons/day

Average daily dose

Absorption

Recent guidelines American Heart Association 2002Circulation 2002;106;523-527

“No definitive evidence... Rely on professional judgement”

“Consuming fructose either free or in the form of sucrose has neither beneficial or adverse effects”

BIG SUGARBrian Mckenna

Update... “Originally proposed as the ideal sweetener

for people with diabetes... Fructose... has been indirectly implicated in the epidemics of obesity and type 2 diabetes”

Circulation 2009;120;1011-1020

Update Upper limit set to reduce heart disease risk

and maintain healthy weight “6 teaspoons per day” for women “9 teaspoons per day” for men

Health effects? 1990s ADA encouraged diabetics to eat

sugar/HFCS 2000s about face due to ↑triglycerides Small RCTs: Rots teeth; raises triglycerides, ↓HDL, ↑BP,

↑urate.Johnson, R.J., et al., Hypothesis: Could Excessive Fructose Intake and Uric Acid Cause Type 2 Diabetes? Endocr

Rev, 2009. 30(1): p. 96-116.

Segal, M.S., E. Gollub, and R.J. Johnson, Is the fructose index more relevant with regards to cardiovascular disease than the glycemic index? European Journal of Nutrition, 2007. 46(7): p. 406-17.

Sugar - What has changed? GI ignores fructose –Sugar half fructose (half

glucose) 4x as sweet as glucose Links to gout, diabetes Human studies limited, Does not trigger satiety hormones→↑hunger

E.g. Insulin, CCKJohnson, R.J., et al., Hypothesis: Could Excessive Fructose Intake and Uric Acid Cause Type 2 Diabetes? Endocr Rev, 2009. 30(1): p. 96-116.

Segal, M.S., E. Gollub, and R.J. Johnson, Is the fructose index more relevant with regards to cardiovascular disease than the glycemic index? European Journal of Nutrition, 2007. 46(7): p. 406-17.

Refined carbohydrate (high GI) Reduced risk of chronic disease

Heart disease, cancer, gallstones.Barclay A, Petocz P, McMillan-Price J, Flood V, Prvan T, Mitchell P, et al. Glycemic

index, glycemic load, and chronic disease risk—a metaanalysis of observational studies. Am J Clin Nutr 2008;87:627-37

Modest weight lossThomas D, Elliott E, Baur L. Low glycaemic index or low glycaemic load diets for

overweight and obesity. Cochrane Database of Systematic Reviews 2007;Art. No.: CD005105. DOI: 10.1002/14651858.CD005105.pub2(3).

What about saturated fat? Meta-analyses now show no link between

eating saturated fat and heart disease.

Skeaff CM, Miller J. Dietary Fat and Coronary Heart Disease: Summary of Evidence from Prospective Cohort and Randomised Controlled Trials. Ann Nutr Metab 2009;55:173–201

Mente A, de Koning L, Shannon HS, Anand SS (April 2009). A systematic review of the evidence supporting a causal link between dietary factors and coronary heart disease. Arch. Intern. Med. 169 (7): 659–69.

Sugar and CHD?

Dental cariesCoronary Heart

Disease

Sugar consumption

Sugar addiction? Yes in rats Anecdote in humans

Food addiction-evidence Neural pathways (dopamine) Correlation between obesity & receptor

density like other addictions Automaticity – serving size, availability Rise in sugar consumption worldwide over

last 40 years. Rodents – sugar induces withdrawal; fat

does not.

Dairy photo

Food addiction in the headlines…

After the publicity... my inbox... “For the first three weeks I cut all

processed sugar and flour from my diet and suffered mood swings with extreme tension and depression, even a sense of hopelessness at times, I had horrible stomach pains, all my joints and muscles throbbed, and I had the shakes constantly.”

“I don't even know how to describe the horrible headaches that went along with all this. People who knew me started thinking I was hiding a drug problem.”

“The worst physical symptoms have been gone for about two weeks now, and the cravings are finally starting to subside… I look at birthday cake today and all I see is myself curled up in the foetal position crying in bed. “

Overeater’s Anonymous “When you are addicted to drugs you put

the tiger in the cage to recover; when you are addicted to food, you put the tiger in the cage, but take it out three times for a walk”

Kerri-Lynn Murphy Kriz

Critique: Academia “Any addictive type of hypothesis can't

explain the rise that we've seen over the last 20 to 30 years of obesity.

Prof. Boyd Swinburn, Professor of Population Health, Deakin University (now U of A) 13 Jan 2009

Citique: Academia and Industry “The data quoted on sugar consumption in

New Zealand are presented misleadingly and are not correctly referenced to primary sources.”

Parnell and colleagues NZMJ 2010

“Sugar Research Advisory Service”

BIG SUGAR

Brian McKenna

http://www.youtube.com/watch?v=8hcAjyOFX1M

SO WHAT?

Conclusions Nutrition ignores hunger, instead focuses

on energy Low energy or low fat idea unhelpful for

populations Sugar intake continues to rise Likely subtle addiction to refined carb and

sugar

Conclusions

↓ sugar likely to ↓ Heart disease Obesity Diabetes Dental caries Other diseases?

No downsides except $$$

What about children? Marketing sugary

foods common

My advice… Zero sugar (alternatives) Whole grains over white flour (low GI) No low fat food – tends to be high in

sugar or refined carbohydrate

Other lessons Ink is a powerful weapon The ideals of science are only that Science integrates Don’t be scared of the big guys... History over latest and greatest

The book

Other reading Freedman “Wrong: Why experts keep

failing us and how to know when not to trust them”. Little, Brown and Company, 2010. (journalist)

Taubes G. The Diet Delusion. New York: Vermilion; 2007. (physicist/writer)

Gillespie D. Sweet poison. Sydney: Penguin; 2008 (lawyer)

Thank you!