These articles on insulin resistance are an attempt to provide reasons for resisting the typical approach to managing diabetes. I find that when the focus is primarily on blood sugar readings, we tend to forget the larger picture and ignore factors that, if addressed, have the potential to improve the underlying insulin resistance. I realize these are not exciting reads. However, I hope they will broaden our perspective to see beyond the popular cultural trends. Knowledge, distilled down to practical application, has the potential to turn your health around. As we saw last month, there are different variables that preclude insulin resistance. This month we are going to look at a couple more.
Low carbohydrate diets are commonly prescribed and followed by individuals who are either diagnosed with or trying to prevent type 2 diabetes. The dramatic elimination or reduction in refined, processed carbohydrates has improved blood sugar control and helped with weight loss in many. This way of eating, however, has its down sides, one of which pertains to insulin sensitivity. As is the case with many therapies, it is possible to improve symptoms while the disease process marches on.
Women with a history of insulin resistance during pregnancy, called gestational diabetes (GDM), have a sevenfold higher risk of developing type 2 diabetes.1 As part of the Nurse’s Health Study, 722 out of 4,502 women with a history of GDM developed type 2 diabetes within an approximate 20-year period. During this time researchers found low carbohydrate eating patterns that emphasized animal-derived protein and fat were associated with an increased risk of developing type 2 diabetes (T2DM). “We observed that a dietary score representing a low-carbohydrate, high animal protein, and high animal fat dietary pattern was significantly and positively associated with T2DM risk among women with a history of GDM. These associations were partly explained by BMI. By contrast, a dietary score representing a low-carbohydrate, high vegetable protein and high vegetable fat dietary pattern was not associated with the risk of developing T2DM.”2 In other words, while being overweight heightened the impact of low-carb eating, the researchers emphasized that the source of the protein impacted the eventual outcome of whether or not an individual was diagnosed with diabetes.
This is not the only research that has found this kind of association. A European study followed 16,154 individuals from eight European countries for an average of 12 years. Here too, those who consumed more animal protein experienced increased risk of type 2 diabetes.3
Researchers found that animal protein was indeed positively associated with measured insulin resistance.
Within the Adventist Health Study , a cross-sectional analysis was conducted with the intent of examining “the relation between total protein intake and the type of dietary protein on insulin resistance in healthy older to elderly individuals who consume a wide range of plant and animal protein and a predominantly plant-based diet.”4 Data from 548 participants was analyzed. Insulin resistance was calculated (HOMA-IR) in each and compared with total and specific protein intakes. Adjustments in the analysis were made for age, waist circumference, ethnicity, physical activity, glycemic load, etc. All participants were non-smokers, non-alcohol users. Researchers found that animal protein was indeed positively associated with measured insulin resistance. The association was strongest for those with normal waist circumference and significant animal protein intake compared to vegetable protein intake. No association was observed between plant protein and insulin resistance.
Diet composition matters. When animal protein makes up a good share of the diet and vegetable foods are low, insulin resistance and its corresponding disease manifestations, such as type-2 diabetes, are more likely to result. “In healthy subjects, animal protein intake intensifies insulin resistance whereas plant-based foods enhance insulin sensitivity.”5 The researchers bring out what they found in their review of the research. Insulin resistance during pregnancy has been strongly associated with processed and unprocessed meat intake before becoming pregnant. On the other hand, a high vegetable protein intake before becoming pregnant is associated with a much lower risk. It also points out the documented observation that when population groups adopt more of our standard American diet, with its emphasis on animal foods, from a traditional one that emphasized more plant-based foods, “a remarkable rise in the frequency of type-2 diabetes” is experienced.6 They also make the enlightening statement that “the association of animal protein intake with insulin resistance is independent of body mass index. In obese individuals that consume high animal protein diets, insulin sensitivity does not improve following weight loss. Diets aimed to lose weight that encourage restriction of carbohydrates and elevated consumption of animal protein intensify insulin resistance, increasing the risk of developing type-2 diabetes and cardiovascular disease.”7
You have more than likely heard the saying “this is a perfect storm.” A perfect storm would contain the individual elements, circumstances, or events acting in synchrony to aggravate nature in some way. Collectively, these ingredients act as a synergy of forces leading to a release of energy much greater than any of its individual contributors would ever generate. It appears to me that we are fine-tuning the recipe for a perfect storm when it comes to altering our body’s response to insulin. If we look at these factors in the light of a mathematical equation in which insulin resistance is the product sitting to the right of the equal sign, then perhaps by modifying the addends we will come out with a different sum.
- Wei Bao et al., “Low Carbohydrate-Diet Scores and Long-term Risk of Type 2 Diabetes Among Women with a History of Gestational Diabetes Mellitus: A Prospective Cohort Study,” Diabetes care, vol. 39, 1 (2016): 43-9, doi:10.2337/dc15-1642.
- Monique van Nielen et al., “Erratum. Dietary protein intake and incidence of type 2 diabetes in Europe: the EPIC-InterAct case-cohort study, Diabetes Care, 2014;37:1854-1862,” vol. 38, 10 (2015): 1992.
- Bahar Azemati et al., “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 e000299, March 15, 2017.
- M. Adeva-Andany et al., “Effect of diet composition on insulin sensitivity in humans,” Clin Nutr ESPEN, 2019 Oct;33:29-38.
Risë Rafferty, RDN
Risë is a Registered Dietitian Nutritionist (RDN) and has been writing and teaching about health for many years. She loves the health message and takes great pleasure in seeing people thrive by the application of its principles. Her research and down-to-earth manner allow her to offer up the health message in both an intelligent and accessible manner. She and her husband, James Rafferty, have two children.