Talk given at St George's Anglican Church, 7/05/2011. The link to the video is: http://www.youtube.com/watch?v=8hcAjyOFX1M

1. Food matters:
why we are getting fatter
and what can we do about
it?
Simon Thornley
Public Health Physician & Lecturer
University of Auckland

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

3.  Dairy photo

4.  Museum photo…

5. What is science?
 “In God we trust, all others bring data”
 “First establish the facts, then seek to
explain them” Aristotle
 Anarchistic
 Consensus not useful
 Hypothesis and argument
 Disproof useful, not proof.
 Probabilities over absolutes

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

7. Is there an obesity epidemic?

8. 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 countries
Taubes G. The Diet Delusion. New York: Vermilion; 2007.

9. 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)

10. MY STORY

11. My thoughts on obesity
Medical training Public Health Research Research
Traditional Understanding Similarities Critique of
Nutritional theory addiction between energy density
- Energy density obesity and Focus on sugar
smoking
1994 2005 2007 2011

12. Tobacco withdrawal

13. In detail
Signs and Duration Proportion
symptoms (weeks) (%)
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

14. Addiction? Automatic behaviour
Rational behaviour Automatic Addiction –
e.g. Planning, behaviour? Automatic,
Picking up children e.g. breathing withdrawal, can‘t
after work stop, causes harm
e.g. heroine
Mid brain/brain
Cortex
stem

15. Negative re-inforcement
Withdrawal
discomfort
Puff
cigarette
Nicotine
metabolised
Withdrawal
More relief
puffs

16. How to profit from tobacco...?
Nicotine delivery
Royal College of Physicians, Nicotine in Britain, 2000

17. FOOD ADDICTION?

18. Carbohydrate?

19. 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”

20.  “Ihad 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.”

21. 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?

22. Bread - White vs Vogel’s

23. Glucose: glycemic index?

24. What about sugar?
 Sugar is actually moderate GI

25. WHAT DO WE KNOW ABOUT
SUGAR?

27. Brian Mckenna
BIG SUGAR

29. 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.

30. Sugar – traditional views
 30% increase over last 30 years
Popkin 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

31. Average NZ consumption:
 UN statistics (‗07)– 153g/day
= 38 teaspoons/ day
 17% of total energy
 Compare – 1961 – 33 teaspoons/day

32. Average daily dose

33. Absorption

34. Recent guidelines
 American Heart Association 2002
Circulation 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”

35. Brian Mckenna
BIG SUGAR

37. 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

38. 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

39. 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.

40. 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, CCK
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.

41. 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 loss
Thomas 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).

42. 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.

43. Sugar and CHD?
Sugar
consumption
Coronary Heart
Dental caries
Disease

44. Sugar addiction?
 Yes in rats
 Anecdote in humans

45. 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.

46.  Dairy photo

47. Food addiction in the headlines…

48. 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.”

49.  “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.”

50. “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. “

51. 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

52. 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. It's not that
the whole population becoming more of
an addictive personality type or whatever.
I think there are other factors to explain
obesity at a population level.”
Prof. Boyd Swinburn, Professor of Population Health,
Deakin University 13 Jan 2009

53. Citique: Academia and Industry
 “We write in response to Thornley et al’s
viewpoint article “The New Zealand sugar
(fructose) fountain...” 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

54. “Sugar Research Advisory Service”

55. Brian McKenna
http://www.youtube.com/watch?v=8hcAjyOFX1M
BIG SUGAR

57. SO WHAT?

58. Conclusions
 Nutrition ignores motivation to eat, instead
focuses on energy
 Low energy or low fat approach has been
unhelpful for populations
 Sugar intake continues to rise
 Likely subtle addiction to refined carb and
sugar

59. Conclusions
↓ sugar likely to ↓
 Heart disease
 Obesity
 Diabetes
 Dental caries
 Other diseases?
 No downsides except $$$

60. What about children?
 Big sugar

61. 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

62. Other lessons
 Ink is a powerful weapon
 The ideals of science are only that
 ‗Authorities‘ hold power over junior
scientists (jobs, grants)
 Going alone takes courage
 History over latest and greatest

63. The book
 ―Sickly sweet: sugar, refined carbohydrate,
addiction and global obesity‖
 Nova
 To be released in about three months.

64. Publications
 Thornley S et al. The New Zealand sugar (fructose) fountain: time
to turn the tide? NZMJ 2010.
 Thornley S et al. Carbohydrate withdrawal: is recognition the first
step to recovery? NZMJ 2010
 Thornley S et al. Per capita sugar consumption is associated with
childhood asthma prevalence. Primary Care Respiratory Journal.
2011.
 Thornley S et al. The obesity epidemic: is glycemic index the key to
unlocking a hidden addiction? Medical Hypotheses. 2008

65. 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)

66. Thank you!