Eating mammal meat or processed meats is associated with increased risk for diabetes, particularly if the meat is cooked at high temperatures (Journal of Hepatology, March 19, 2018). The authors showed that eating red or processed meat is associated with excess fat in the liver that can cause high blood sugar levels. The authors believe that it is not the cholesterol or saturated fat in mammal meat that links meat to diabetes; it is the heterocyclic amines (HCAs) that are formed when the meat is cooked for a long time at high temperatures.

Another article reviewed three prospective studies to show that the highest risk for diabetes was with red meat, chicken or fish that was cooked in an open flame or at high temperatures without water (grilling, barbecuing, broiling, roasting or frying), and cooked for a long time or long enough to brown or char the surface (Diabetes Care, March 14, 2018). When you cook with water, the sugar in foods combines with water to form harmless byproducts. Cooking without water causes the sugars in meats to combine with proteins to form harmful HCAs and PAHs (polycyclic aromatic hydrocarbons).

Many previous studies have shown an association between diabetes and eating red meat two or more times per week (Am J Clin Nutr, Oct 2011;94(4):1088-96). Diabetes was also strongly associated with consumption of processed meats, refined grains (flour) and sugar-sweetened beverages. Risk for diabetes was moderately increased by some vegetables and fruit, eggs, dairy and fish; and was not associated with eating beans or nuts (Eur J Epidemiol, May 2017;32(5):363-375). Other studies show that soybeans are associated with reduced risk for diabetes (Eur J Clin Nutr, Dec 2016;70(12):1381-1387). See Why Meat May Increase Risk for Diabetes
How Sugar Can Fill Your Liver with Fat

How to Reduce Your Consumption of HCAs and PAHs
• Reduce your intake of animal-derived foods that are high in fat and protein, since most of the cooking methods used for these foods will cause HCAs and PAHs to form.
• Limit grilled, broiled and fried foods.
• Limit foods that have been browned or charred in the cooking process.
• Use water-based cooking methods whenever possible: steaming, simmering, boiling, stewing or microwaving. Water prevents the sugars from attaching to proteins and fats.
• When cooking animal products, include acidic ingredients such as lemon juice or vinegar if possible (J Am Diet Assoc, June 2010;110(6):911-16).
• Where possible, cook for shorter durations and at lower temperatures.
• Eat lots of vegetables, fruits, whole grains and beans. Include plenty of foods that are eaten raw, such as fresh vegetables and fruits. Fresh fruit is associated with reduced susceptibility for diabetes (PLoS One, April 11, 2017).