Eating Animal Proteins Increases the Risk for Type 2 Diabetes
You probably know that being overweight and obese can elevate the risk for type 2 diabetes. The types of specific foods you eat also affect your health. Did you know that eating meat increases your risk of becoming a type 2 diabetic? If you are a meat-lover, you need to see the latest research. Type 2 diabetes occurs when the body’s ability to control blood glucose through insulin secretion weakens. This can be due to insulin resistance, which happens when insulin is unable to trigger glucose uptake by cells in the body. Sometimes in type 2 diabetes, the production of insulin in the pancreas declines. Recently, many studies have been published on an increased risk of type 2 (adult onset) diabetes related to meat.
A 2013 meta-analysis on meat and diabetes found a much higher risk of diabetes with total meat consumption (Feskens, Sluik, & van Woudenbergh, 2013). You might wonder why this is the case! Let’s look at what meat contains. Meat has the following nutritional and non-nutritional constituents that are relevant to the risk of diabetes: saturated fatty acids, trans fatty acids, dietary cholesterol, animal protein, specific amino acids, heme-iron, sodium, nitrates, nitrites, nitrosamines, and advanced glycation end products. A high intake of saturated fats and trans-fats in animal fats are linked with insulin resistance. The heme-iron in meat may lead to the build-up of cancer-causing free radicals, and the oxidative stress from the production of free radicals may cause chronic inflammation, cardiovascular disease, and even type 2 diabetes. The advanced glycation end products are highly oxidant chemicals which lead to diabetes and its complications, while promoting oxidative stress and inflammation. (Refer to our article written on glycation.) Analyses of food demonstrated that meats have the highest content of advanced glycation end products, especially roasted, fried, and broiled meat. Restricting these foods might suppress these inflammatory effects. Hence, eliminating these foods or modes of cooking with high content of glycation end products may lower the vast burden of these toxins in patients of diabetes. These glycotoxins might be one aspect of the association between increased consumption of roasted, fried, or broiled meat and the consequent development of type 2 diabetes. Steaming and boiling meat will be better options.(Peppa, Goldberg, Cai, Rayfield, & Vlassara, 2002)
Another investigation took place in eight European countries. There were 12,403 incident cases of type 2 diabetes among 340,234 adults during an 11.7-year period of follow up. Randomly, 16,835 subjects were selected and hazard ratios for incident diabetes according to meat consumption were determined. There was an 8% risk for type 2 diabetes for every 50 grams of routinely meat consumption. To put this into perspective, eating a quarter of a chicken breast per day may significantly increase your risk of diabetes. (The InterAct Consortium, 2013)
Perhaps, it could be the glycation end products, the saturated fats, the trans-fats, or the heme-iron in meat that are responsible for a higher risk of type 2 diabetes. We already learned that processing meat increases their content of glycotoxins. Oxidized saturated fats from animal sources have been shown to cause diabetes. The same is true for trans-fats, which are high in beef, lamb, and mutton-derived products, as they have adverse metabolic effects on insulin sensitivity. Heme-iron in meat weakens insulin sensitivity and increases blood glucose concentration, increasing the risk of type 2 diabetes. What is notable is that heme-iron found in meats is more bioavailable in the body than non-heme iron, as its absorption does not depend on body’s iron status and is less impacted by the various foods and nutrients in the body. Heme-iron, therefore, promotes the formation of carcinogens (cancer-causing substances) called nitrosamines. It is worthwhile understanding that the nitrosamines can actually be produced in the cooking process of meat. (The InterAct Consortium, 2013)
A population-based cohort study published earlier this year, known as the Singapore Chinese Health Study, assessed the risk of type 2 diabetes due to intake of red meat, poultry, fish/shellfish, and heme-iron. The investigators recruited 63,257 Chinese adults (ages 45-74 years) between 1993 and 1998. The diet of the subjects was assessed at the time of enrollment. The subjects filled out a semiquantitative food-frequency questionnaire listing 165 commonly consumed food items to report at the initial interview. (Talaei, Wang, Yuan, Pan, & Koh, 2017)
Out of 63,257, exactly 45,411 adults (mean age, 55.2 years; 57.3% women) participated in the study. The subjects were put into four groups depending on their meat intake. Type 2 diabetes, as diagnosed by medical professionals, was reported during two follow-up interviews between 1999 to 2004 and 2006 to 2010. In an average follow-up of about 10.9 years, 5,207 incident cases of type 2 diabetes were registered. (Talaei, Wang, Yuan, Pan, & Koh, 2017)
There was a much higher hazard ratio of type 2 diabetes for those taking red meat and poultry compared to fish/shellfish. Once the heme-iron was adjusted, red meat intake was linked to a significant risk of type 2 diabetes. Heme-iron was linked to a greater risk of type 2 diabetes even after further adjustment for red meat intake. (Talaei, Wang, Yuan, Pan, & Koh, 2017)
The Chinese adults substituted one routine serving of red meat or poultry with fish/shellfish, and the risk for type 2 diabetes decreased by 25%. Specifically, there was a 26% decrease in risk for type 2 diabetes when one daily serving of red meat was substituted with fish/shellfish and a 22% decrease in risk when one daily serving of poultry was substituted with fish/shellfish. Replacing red meat with poultry indicated no difference in risk for type 2 diabetes. The researchers concluded that red meat and poultry are linked to a higher risk of type 2 diabetes. These links were adjusted fully for poultry and partially for red meat by heme-iron intake, as the risk of diabetes to some degree is due to heme-iron content of red meat. (Talaei, Wang, Yuan, Pan, & Koh, 2017)
Yet another study scrutinized the biochemistry of meat and its link to diabetes. There is an aging enzyme called mTOR, which is encoded by the MTOR gene in the body. Excess food consumption of meat products can over-stimulate the mTOR pathway, and this might be a critical factor underlying the diabetes epidemic. Animal proteins in meat stimulate insulin and “insulin-like growth factor-1 (IGF-1) signaling” as well as provide high amounts of the leucine. Insulin-like growth factors promote cancer. The leucine in meat is a primary and independent stimulator for mTOR activation and burns out the insulin-producing beta cells in the pancreas. Leucine is a factor in the development of type 2 diabetes. That is why besides oxidized high fat and high sugar, a serious attention must be paid to the routine dietary intake of leucine-rich meats. (Zoncu, Efeyan, & Sabatini, 2011)
Generally speaking, one lowers leucine levels by lowering the intake of animal proteins. You can eat more plant-based proteins to avoid the risk of type 2 diabetes. For example, you would need to eat 100 apples or 4.2kg of white cabbage to get the same amount of leucine as compared to 100g of steak. These estimates show the great deviations in leucine amounts from animal meat versus a vegetarian diet. (Melnik, 2012)
Furthermore, we know that a sedentary lifestyle filled with stress and a high glycemic diet full of saturated fats and trans fats alongside a low-fiber, phytonutrient-poor diet causes obesity and diabetes. However, there are many environmental toxins (such as organic pollutants and heavy metals) in our foods that cannot be ignored as well. The environmental toxins in our foods cause weight gain and insulin resistance, contributing to the epidemic of obesity and diabetes. (Hyman, 2010)
Here is a case in point of how toxins in the environment cause obesity and diabetes in babies. In 2006, researchers at Harvard School of Public Health discovered that the rates of obesity in infants under 6 months old increased 73% since 1980. This is unrelated to diet and lack of exercise. We know that babies receive breast milk or formula. An average newborn has 287 chemicals in the umbilical cord blood, out of which 217 are neurotoxic. These chemicals cause obesity and diabetes in babies. (Hyman, 2010)
It is interesting there seems to be a clear excess of diabetes amongst workers in the meat industry. This might be due to their exposure to infectious agents such as viruses in fresh cuts of meat, including poultry (The InterAct Consortium, 2013). Another possibility for this could be direct exposure of industrial pollutants, occupational accidents, and the toxic environment.
Every year, millions of pounds of chemicals and heavy metals are dumped into our environment by the food industry, which end up in our foods (Hyman, 2010). Almost 95% of the persistent organic pollutants in our diet come from our consumption of animal fats (Magliano, Loh, Harding, Botton, & Shaw, 2014). Now stop and think! What kinds of foods are we buying and eating every day?
There is a lot of evidence that supports the role of animal protein in the development of diabetes. If you are a non-vegetarian, you need to lower your intake of red meat if not completely eliminate it. For a healthier alternative, you might substitute red meat with white meat like organic chicken breast and fish once in a while. But what about fish and diabetes?
Six meta-analyses showed that fish consumers in the United States are at a greater risk for diabetes. There was a 5% increase in risk for diabetes with a weekly serving of fish and a 35% risk with a daily serving of fish. Insulin-producing cells in the pancreas do not function properly in individuals who eat two or more servings of fish a week. This could be caused by environmental contaminants such as dioxins and mercury that are found in fish. There is growing evidence that these pollutants cause diabetes. (Greger, Fish & Diabetes, 2014)
The best option would be to avoid domesticated meat completely. One study compared meat from captive and wild pheasants and found a lot more pro-inflammatory saturated fat in domesticated birds, which is an invitation to health issues such as obesity and diabetes. Wild animals are a healthier meat option than the store-bought meat (Greger, Modern Meat Not Ahead of the Game, 2012). After looking at the scientific published research, it would be best to eliminate meat or cut down consumption of meat from your diet as much as possible. For best results, eat a plant-based diet, rich in organic fruits and vegetables. Know the source of your food. Buy local. Local, organic foods are environmentally friendly and free of toxins. They may be slightly more expensive, but they are a healthier option.
- Feskens, E. J., Sluik, D., & van Woudenbergh, G. J. (2013, April). Meat Consumption, Diabetes, and Its Complications. Curr Diab Rep., 13 (2), 298-306.
- Greger, M. (2012, October 10). Modern Meat Not Ahead of the Game. Retrieved from NutritionFacts.org.
- Greger, M. (2014, May 2). Fish & Diabetes. Retrieved from NutritionFacts.org.
- Greger, M. (2015, August 21). Why Is Meat a Risk Factor for Diabetes? Retrieved from NutritionFacts.org.
- Hyman, M. A. (2010, Mar/Apr). Environmental Toxins, Obesity, and Diabetes: An Emerging Risk Factor. Alternative Therapies, 16 (2).
- Magliano, D., Loh, V., Harding, J., Botton, J., & Shaw, J. (2014). Persistent organic pollutants and diabetes: A review of the epidemiological evidence. Diabetes & Metabolism, 40, 1-14.
- Melnik, B. C. (2012, March 15). Leucine signaling in the pathogenesis of type 2 diabetes and obesity. World J Diabetes, 3(3), 38-53.
- Peppa, M., Goldberg, T., Cai, W., Rayfield, E., & Vlassara, H. (2002, October). Glycotoxins: A Missing Link in the “Relationship of Dietary Fat and Meat Intake in Relation to Risk of Type 2 Diabetes in Men”. Diabetes Care, 25(10).
- Sodhi, V., & Mulakaluri, A. (2014, September 2). Ayurvedic and Naturopathic Medical Clinic. Is Your Cooking Making Your Food Toxic?
- Talaei, M., Wang, Y.-L., Yuan, J.-M., Pan, A., & Koh, W.-P. (2017, August 22). Meat, Dietary Heme Iron, and Risk of Type 2 Diabetes Mellitus: The Singapore Chinese Health Study. American Journal of Epidemiology.
- The InterAct Consortium. (2013). Association between dietary meat consumption and incident type 2 diabetes: the EPIC-InterAct study. Diabetologia, 56, 47-59.
- Zoncu, R., Efeyan, A., & Sabatini, D. M. (2011, January). mTOR: from growth signal integration to cancer, diabetes and ageing. Nature Reviews: Molecular Cell Biology, 12