Download Welcome Aboard the Sweet Titanic: Added Sugars, Cancer, Heart

Welcome Aboard the Sweet Titanic: Added Sugars, Cancer, Heart Disease
and Diabetes Dead Ahead?
A. Paul Chous, MA, OD, FAAO, CDE
Tacoma, WA
Essential Questions: Do added sugars increase the risk of diabetes,
cardiovascular disease and cancer? Are some added sugars metabolically more
damaging? Why should eye doctors care?
I. US sugar consumption over the last 50 years
a. net increase of 450 kcal per capita per day
b. concomitant increases in obesity, diabetes, metabolic syndrome, cancer
and heart disease
c. These associations are also co-mingled with decreased rates of
physical activity, increasing environmental toxins, increasing mean
indoor ambient temperatures, an aging population, misguided public
health focus on reducing dietary fats, and improved ability to diagnose
d. Added sugar (sucrose) consumption and fructose consumption
II Is a Calorie Really Just a Calorie?
a. what is a calorie?
b. Hypothesis: The metabolic effects of calories from various foodstuffs
are independent of their total energy content
c. Significance of advanced glycation endproducts (AGES)
-biomarkers of glucose toxicity
-implicated in all diabetes complications, but multiple other
diseases as well (AMD, glaucoma, cataract in the eye)
- formed by high temperature + low humidity cooking
-inhibit SIRT1 gene, shortening lifespan
d. Simple sugars stored in carbohydrates contribute to increased
production of intermediate metabolites that promote disease
1. glucose – advanced glycation endproducts (AGEs)
2. fructose – 99% first-pass hepatic metabolism produces uric acid,
small/dense atherogenic LDL-cholesterol, insulin resistance
III. Sugar and Cancer
a. some studies show significant increase in risk of colon, breast, and
pancreatic cancers
b. Dietary sugar intake associated with increased cancer mortality
c. Warburg Hypothesis: cancer cells preferentially perform anaerobic
glycolysis and have increased insulin receptors to facilitate high
metabolic rate
d. Mechanism of increased cancer risk:
-glucose inhibits vitamin C and promotes hypoxia inducible factor
(HIF) requisite for tumor growth (HIF also implicated in
neovascular AMD)
-Glucose and fructose inhibit beta catenin signaling that renders cancer
cells ‘immortal’
-added sugars increase obesity & diabetes, major risk factor for multiple
cancers via insulin-like growth factor signaling due to excess insulin
- Reducing Risk: reduce sugar intake; possible benefits of metformin; use
of a pyruvate analog that prevents ATP production via anaerobic
glycolysis (2-bromopyruvate)
IV. Diabetes
a. Is increased sugar consumption causally related to increased incidence
of diabetes mellitus?
b. Each 150 kcal/day percapita increase in added sugars increases
population prevalence of DM 1.1%
1. 3.5 million additional cases of T2DM per can of sugar-sweetened
beverage in the US
2. WHO recommendations: < 25 g added sugars/day
c. High fructose corn syrup (HFCS) is metabolized by the liver, yielding
excess uric acid, NAFLD, NO and is causally linked to T2DM
- multiple studies linking hyperuricemia to T2DM
-glucose is not harmless: polyol pathway of aerobic glycolysis
yields fructose and produces AGEs outside of the liver
d. Reducing Risk: keep added sugars < 40 grams/day (ideally < 25 g); eat
foods with fewer AGEs; prevent AGE formation with curcumin and
benfotiamine (lipid soluble thiamine analog); increase macular pigment
with xanthophyll rich diet that increases macular pigment
- low MPOD implicated in diabetes, diabetic retinopathy, but
also…
V. Sugar and Cardiovascular Disease
a. meta-analysis of 39 RCTs shows added sugars increase triglycerides,
LDL cholesterol and blood pressure after all controls
b. Dose increases risk: nearly 3-fold increased risk of death when > 25%
of calories come from added sugars*NHANES data
c. low sugar intake improves HDL cholesterol, TGs in both men and
women and LDL-C in women
e. Fructose appears worse than glucose by fostering small, dense, highly
Atherogenic LDL-C, NAFLD and hepatic insulin resistance; also
Raises hsCRP > glucose
f. Sugar accelerates cell aging by shortening telomeres
g. Sugar increases serum AGEs that predict CV mortality in type 2
diabetes
VI Conclusion: Is dietary sugar consumption linked to CV disease, diabetes and
cancer? Is it linked to ocular disease?
YES
a. the problem of mono versus multifactorial causality
b. practical strategies: keep carbs < 30 grams/meal; keep daily added
sugars < 25grams; substitute whole plant foods and lean protein for
processed carbs/snack foods/soda; avoid AGEs in food preparation;
avoid HFCS
c. Food companies disguise added sugars: (56 names) – read labels!