Major long-term studies show that people with the highest intake of animal products (meat, poultry, eggs, dairy, and fish) have the highest risk of developing type 2 diabetes. People with the lowest intake (i.e. nothing) have the lowest risk of developing type 2 diabetes [1].

There are a number of possible reasons why meat consumption increases the risk of type 2 diabetes. Below we’ll dig into some of the research linking meat to type 2 diabetes.

1. Saturated Fat

Saturated fat, which we predominantly get from eating animal products, readily gets into our cells and can block glucose, contributing to insulin resistance and type 2 diabetes [2]. People who eat animal products have higher levels of intramyocellular lipids (fat in your cells). Saturated fat is one of the main drivers of insulin resistance.

2. Advanced Glycation End-products (AGEs)

When you cook animal protein, particularly at high and dry heat, you produce AGEs. AGEs trigger oxidative stress and inflammation and contribute to insulin resistance [3]. These by-products have also been associated with diabetes, Alzheimer’s, cardiovascular disease, and aging.

3. Nitrites 

Nitrites are commonly used as preservatives in meat, especially processed meat like

sausages, hot dogs, and cured meats. Processed meat contains 50% more nitrites than unprocessed meat. Nitrites are converted to nitrosamines in meat, which generate free radicals in the body, leading to oxidative stress, inflammation, and insulin resistance. Nitrosamines are toxic and can cause direct damage to the pancreatic beta cells that produce insulin. They have been shown to induce type 2 diabetes in animals [4].

4. Heme Iron 

Heme iron is found in animal meat (while non-heme iron is found in plant-based sources). Heme iron is a pro-oxidant, which means it triggers free radicals, oxidative stress, and inflammation in the body [5]. It also interferes with the storage of glucose and causes the liver to release glucose into the blood, contributing to high blood sugar levels. It can also cause direct damage to the beta cells in the pancreas.

5. Dietary Protein 

A high intake of dietary animal protein has been shown to reduce insulin sensitivity by as much as 25% [6]. Studies have shown that swapping animal meat for soy protein (like tofu) significantly improves insulin sensitivity. This is thought to be largely due to the high levels of a phytonutrient called isoflavones in soy proteins [7].

6. Endocrine Disruptors 

Industrial chemicals commonly found in meat have been shown to disrupt our endocrine function (our hormone system), causing insulin resistance and impaired beta cell function [8]. Levels of these chemicals are highest in meat eaters.

7. Trimethylamine Oxide (TMAO)

TMAO is a metabolite of meat and has been shown to exacerbate insulin resistance in mice [9]. TMAO also doubles the risk of cardiovascular events such as a heart attack. 70% of adults with type 2 diabetes die from cardiovascular disease, and 65% of all deaths from cardiovascular disease are from people with type 2 diabetes and prediabetes [10]. Vegans and vegetarians have the lowest levels of TMAO.

If you decide to reduce your meat consumption, what you replace it with is just as important.

Replacing meat with processed or refined carbohydrates is just as harmful as a diet of red meat.  Replacing meat with plant-based whole foods is beneficial on two fronts; you are removing the potentially harmful stuff while adding in more of the good stuff (nutrients found in plant-based whole foods).

Learn How Human Instincts Lead to Overeating and Weight Gain and what you can do about it.

Consider replacing all or some of the meat in your diet with a variety of plant-based whole foods such as:

  • Fruits
  • Vegetables
  • Nuts
  • Legumes, beans, and lentils
  • Healthy oils
  • Whole grains

These plant-based whole foods have been shown to consistently improve insulin sensitivity and reduce the risk of type 2 diabetes.

Article Resources

[1] Sluijs, I., Beulens, J., Van Der A, D., Spijkerman, A., Grobbee, D., Van Der Schouw, Y. (2010). Dietary intake of total, animal, and vegetable protein and risk of type 2 diabetes in the European Prospective Investigation into Cancer and Nutrition (EPIC)-NL study. Diabetes care, Vol.33(1), pp.43-8

[2] Micha, R., Wallace, S. K., and Mozaffarian, D. (2010). Red and processed meat consumption and risk of incident coronary heart disease, stroke, and diabetes mellitus: a systematic review and meta-analysis. Circulation, 121(21), 2271–2283.

[3] Kellow, N. and Savige, G. (2013). Dietary advanced glycation end-product restriction for the

attenuation of insulin resistance, oxidative stress and endothelial dysfunction: a systematic review. European Journal of Clinical Nutrition, 67, 239–248 doi:10.1038/ejcn.2012.220

[4] de la Monte, S.M., Tong, M., Lawton, M. and Longato, L. (2009). Nitrosamine exposure

exacerbates high fat diet-mediated type 2 diabetes mellitus, non-alcoholic steatohepatitis, and

neurodegeneration with cognitive impairment. Molecular Neurodegeneration, Vol.4(54)

[5] Zhao, Z., Li, S., Liu, G., Yan, F., Ma, X., Huang, Z., Tian, H. (2012). Body Iron Stores and Heme-Iron Intake in Relation to Risk of Type 2 Diabetes: A Systematic Review and Meta-Analysis (Ferritin, Heme-Iron Intake and Diabetes). PLoS ONE, Vol.7(7), pp.e41641

[6] Azemati, B., Rajaram, S., Jaceldo-Siegl, K., Sabate, J., Shavlik, D., Fraser, G. E., and Haddad, E.H. (2017). Animal-Protein Intake Is Associated with Insulin Resistance in Adventist Health Study 2 (AHS-2) Calibration Substudy Participants: A Cross-Sectional Analysis. Current Developments in Nutrition, Vol.1(4)

[7] Van Nielen, M., Feskens, E., Rietman, A., Siebelink, E. and Mensink, M. (2014). Partly

Replacing Meat Protein with Soy Protein Alters Insulin Resistance and Blood Lipids in

Postmenopausal Women with Abdominal Obesity, The Journal of Nutrition, Vol.144(9),

pp.1423–1429

[8] Alonso-Magdalena, P., Quesada, I. and Nadal, A. (2011). Endocrine disruptors in the

etiology of type 2 diabetes mellitus. Nature Reviews Endocrinology, Vol.7, pp.346–353

[9] Gao, X., Liu, X., Xu, J., Xue, C., Xue, Y. and Wang, Y. (2014). Dietary trimethylamine N-oxide

exacerbates impaired glucose tolerance in mice fed a high fat diet. Journal of Bioscience and

Bioengineering, Vol.118(4), pp.476-481

[10] Laakso M . (2001). Cardiovascular disease in type 2 diabetes: challenge for treatment and

prevention. Journal of Internal Medicine, Vol.249, pp.225– 235