Download Meat as a Risk Factor for Type 2 Diabetes

Meat as a Risk Factor for
Type 2 Diabetes
Susan Levin, M.S., R.D., C.S.S.D.
American Diabetes Association
Risk factors for overweight adults
• Physical inactivity
• First-degree relative with diabetes
• High-risk race/ethnicity (e.g., African American, Latino, Native American,
Asian American, Pacific Islander)
• Women who delivered a baby weighing > 9 lb or were diagnosed with
GDM
• Hypertension (blood pressure ≥ 140/90 mmHg or on therapy for HTN)
• HDL cholesterol level < 35 mg/dL (0.90 mmol/L) and/or a TG level > 250
mg/dL (2.82 mmol/L)
• Women with polycystic ovarian syndrome
• A1C ≥ 5.7%, impaired glucose tolerance, or impaired fasting glucose on
previous testing
• Other clinical conditions associated with insulin resistance (e.g., severe
obesity, acanthosis nigricans)
• History of CVD
• Meat eater?
American Diabetes Association. Standards of medical care in diabetes—2014. Diabetes Care. 2014;37:S14–S80.
Measuring Meat Consumption
• Categorical – meat vs. no meat
• Gradations
– Scalar
– Dietary patterns
Categorical Variable
Seventh-day Adventists (SDA)
• Avoid alcohol, tobacco, caffeine
• Half vegetarian, half omnivores
• Three studies
Adventist Mortality Study
• ~25,000
– 40% increased risk for meat-eating women
– 80% increased risk for meat-eating men
Snowdon DA, et al. Does a vegetarian diet reduce the occurrence of diabetes? Am J Public Health. 1985;75:507–512.
Adventist Health Study
• ~34,000
– 93% increased risk for meat-eating
women
– 97% increased risk for meat-eating
men
Fraser GE. Associations between diet and cancer, ischemic heart disease, and all-cause mortality in non-Hispanic
white California Seventh-day Adventists. Am J Clin Nutr. 1999;70:S532–S538.
Adventist Health Study-2
• ~61,000
– 2x the risk for meat-eaters
Tonstad S, et al. Type of vegetarian diet, body weight and prevalence
of type 2 diabetes. Diabetes Care. 2009;32:791–796.
Gradations
• Scalar
• Dietary Patterns
Meta-analysis
• ~440,000 participants
– 100 grams of red meat (3.5 oz)  19%
increased risk
– 50 grams processed meat  51%
increased risk
Pan A, et al. Red meat consumption and risk of type 2 diabetes: 3 Cohorts of US adults and an updated meta-analysis.
Am J Clin Nutr. 2011;94:1088–1096.
Nurses’ Health Study I
• ~70,000
– Western dietary pattern
• 49% increased risk of developing diabetes
during 14 years follow-up, compared with
lowest quintile
• Isolating products showed 26% increase risk
for each serving of red meat added and
38% for each serving of processed meat
– Prudent dietary pattern
Fung TT, et al. Dietary patterns, meat intake, and the risk of type 2 diabetes in women. Arch Intern Med. 2004;164:2235–
2240.
Nurses’ Health Study II
• ~91,000
• Processed meat ≥5 x/week  91%
increased risk
• Adjusting for other products in pattern did not
change this finding
• Red meat ≥5 x/week  59%
increased risk
Schulze MB, et al. Processed meat intake and incidence of type 2 diabetes in younger and middle-aged women.
Diabetologia. 2003;46:1465–1473.
EPIC-InterAct Study
• ~ 16,000
• Animal protein
• People who ate the most  22 percent more
likely to develop diabetes
• Each additional 10 grams of protein, the risk
for DM went up by 6 percent.
Van Nielen M, et al. Dietary protein intake and incidence of type 2 diabetes in Europe: the EPIC-INTERACT case-cohort study.
Diabetes Care. 2014;37:1854-1862.
Conclusion
While a Western dietary pattern is associated
with diabetes risk, meat consumption increases
diabetes risk independently of dietary pattern.
What About Fish?
• ~195,000
– Nurses’ Health Study I and II, Health
Professionals Follow-up Study
– Fish ≥5 x/week  22% increased risk for
developing DM during 14-18 year followup, compared with fish < 1/month
• ~20,000
– EPIC and Multiethnic Cohort Study
– Fish consumption higher in those with DM
Kaushik M, et al. Long-chain omega-3 fatty acids, fish intake, and the risk of type 2 diabetes mellitus. Am J Clin Nutr.
2009;90:613–620.
Nöthings U, et al. Food intake of individuals with and without diabetes across different countries and ethnic groups.
Eur J Clin Nutr. 2011;65:635–641.
Mechanisms of Action
Body weight
Visceral fat
Inflammation
Diabetes
Intracellular
lipid
Nitrates
Iron
Body Weight
• Observational studies show meat eaters are
heavier
• High-fat diet
• Low-fiber diet
• Possible association between animal protein and
weight
– Insulin resistance aggravated by certain amino acids
and fat?
– SFA in meat increase insulin response which reduces
fat oxidation?
Berkow S, et al. Vegetarian diets and weight status. Nutr Rev. 2006;64:175–188.
Barnard ND, et al. The effects of a low-fat, plant-based dietary intervention on body weight, metabolism, and insulin sensitivity. Am J Med.
2005;118:991–997.
Bujnowski D, et al. Longitudinal association between animal and vegetable protein intake and obesity among men in the United States: The
Chicago Western Electric Study. J Am Diet Assoc. 2011;111:1150–1155.
Visceral Fat
• Eliminating fat may
reduce visceral fat and
improve insulin
sensitivity, compared with
conventional diabetes
diet.
• ↑ visceral fat  ↑
insulin resistance
Kahleova H, et al. Vegetarian diet improves insulin resistance and oxidative stress markers more than conventional diet in
subjects with type 2 diabetes. Diabet Med. 2011;28:549-559.
Hamdy O, et al. Metabolic obesity: The paradox between visceral and subcutaneous fat. Curr Diabetes Rev. 2006;2:367–373.
Intracellular Lipid
• IMCL aggravates
insulin resistance
• Heart of the problem
and solution
• Avoiding animal
products  ↓ IMCL
Sparks LM, et al. A High-fat diet coordinately downregulates genes required for mitochondrial oxidative
phosphorylation in skeletal muscle. Diabetes. 2005;54:1926–1933.
Iron
• Pro-oxidation damages tissues
• Associated with insulin resistance
• Reductions associated with increased
sensitivity
Rajpathak SN, et al. The role of iron in type 2 diabetes in humans. Biochim Biophys.Acta. 2009;1790:671–681.
Hua NW, et al. Low iron status and enhanced insulin sensitivity in lacto-ovo-vegetarians. Br J Nutr. 2001;86:515–519.
Nitrates
Preservatives may explain increased risk often
seen with processed meat products specifically.
Pereira EC, et al. Biomarkers of oxidative stress and endothelial dysfunction in glucose intolerance and diabetes
mellitus. Clin Biochem. 2008;41:1454–1460.
Inflammation
• Meat-based diets positively associated with
biomarkers of inflammation
• Plant-based inversely associated with
biomarkers of inflammation
Barbaresko J, et al. Dietary pattern analysis and biomarkers of low-grade inflammation: A systematic literature review.
Nutr Rev. 2013;71:511–527.
Ley SH, et al. Associations between red meat intake and biomarkers of inflammation and glucose metabolism in
women. Am J Clin Nutr. 2010:99:352–360.
Common Nutrition Questions
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Protein
B12
Iron
Omega-3
Protein
Of the approximately 20 different amino acids
used by the body, nine (essential amino acids)
cannot be synthesized by the body and must be
obtained from the diet.
Protein
• It is easy to meet protein
needs without meat.
• Amino acids that are low in
some plants are high in
others – usually reflected in
traditional meals such as
beans and rice.
– Grains are low in lysine
while beans are high in
lysine.
• Complementary proteins do
not need to be consumed at
the same meal.
Young et al. Plant proteins in relation to human protein and amino acid nutrition. Am J Clin Nutr. 1004;59:1203S-1212S.
Protein Sources
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•
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Legumes = 15 grams/cup
Tofu = 20 grams/cup
Brown rice = 5 grams/cup
White rice = 4.25 grams/cup
White-flour spaghetti = 8.1 grams/cup
Quinoa = 8.4 grams/cup
Soymilk = 7.1 grams/cup
Broccoli = 2.6 grams/cup
Source: USDA National Nutrient Database for Standard Reference. Nutrient Data Laboratory Web site,
http://www.nal.usda.gov/fnic/foodcomp/search/.
Vitamin B12
(Cobalamin)
Produced by microorganisms – plants and
animals can not synthesize B12.
Vitamin B12
• Needs are small – 2.4 micrograms
per day.
• Ability to absorb B12 decreases with
age because of a decrease in
intrinsic factor in the gut. Anyone
over the age of 50 should
supplement with B12.
• Reliable sources include
supplemented foods and
supplements.
• Only supplement someone
following a plant-based diet needs
to take.
Iron
• Iron is only lost through bleeding, although very small
amounts are excreted through feces, sweat, and exfoliation.
• Men and post-menopausal women should never take an iron
supplement.
Iron
• Vegetarians tend to consume more iron than their meateating counterparts.
• Non-heme regulation vs. heme
• Non-heme iron is sensitive to enhancers and blockers
– Blockers: phytates, calcium, polyphenolics
– Enhancers: vitamin C and other organic acids, soaking
• Although vegetarian adults have lower iron stores than
nonvegetarians, anemia does not afflict vegans any more than
meat eaters. In addition, there may be some benefits to
having low iron stores.
Craig WJ, Mangels AR. Position of the American Dietetic Association: Vegetarian Diets. J Am Diet Assoc.
2009;109:1266-1282.
Iron Sources
Grains – Bran flakes (1 cup)
– Oatmeal (packet)
– Brown rice (1/2 cup cooked)
10.5 mg
8.2 mg
0.4 mg
Vegetables (1/2 cup cooked) – Spinach
– Swiss chard
– Pumpkin
– Kombu (8 g dry or < 2 TBS)
– Nori (8 g dry or < 2 TBS)
3.2 mg
2.0 mg
1.7 mg
22.1 mg
3.7 mg
Source: USDA National Nutrient Database for Standard Reference. Nutrient Data Laboratory Web site,
http://www.nal.usda.gov/fnic/foodcomp/search/.
Iron Sources
Fruits –
Prunes (1/4 cup)
Apricots, dried (1/4 cup)
1.2 mg
0.9 mg
Legumes (1/2 cup cooked) –
Black-eyed peas
Garbanzo beans
Lentils
2.2 mg
2.4 mg
3.3 mg
Soyfoods Soybeans (1/2 cup cooked)
Tofu, firm (1/2 cup)
4.4 mg
6.6 mg
Other Blackstrap molasses (1 Tblesp)
Pumpkin seeds (2 Tblesp)
3.6 mg
2.5 mg
Omega-3
• There are two essential fatty acids: omega-6 and omega-3.
• ALA, an 18-carbon omega-3 fatty acid, is converted to
eicosapentaenoic acid (EPA) which, in turn, can be elongated
to docosahexaenoic acid (DHA).
Omega-3
• Americans consume tremendous amounts of
omega-6s compared to omega-3s.
• Lop-sided ratio makes it difficult for omega-3s
to impart their anti-inflammatory effects.
• The AI for omega-3 for men is 1.6 g/d (14
calories) and for women is 1.1 g/d (10 calories).
• Aim for a 4:1 ratio.
• Happens naturally with a low-fat, plant-based
diet.
In Summary
Vegetarian diets are often associated with a
number of health advantages, including lower
blood cholesterol levels, lower risk of heart
disease, , lower blood pressure levels, and lower
risk of hypertension and type 2 diabetes.
- The Academy of Nutrition and Dietetics
Craig WJ, et al. Position of the American Dietetic Association: vegetarian diets. 2009;109:1266-1282.
Thank You
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