Even when the analysis was limited to nondiabetic participants, the study still showed a significant relationship between higher intake of red and processed meat, and insulin resistance (J Hepatol. 2018 Mar 20. doi: 10.1016/j.jhep.2018.01.015).
“It can be claimed that the harmful association with meat may, at least partially, be related to a generally less healthy diet or lifestyle characterizing people who eat more red or processed meat, rather than a causal effect of meat,” wrote Shira Zelber-Sagi, PhD, of the department of gastroenterology at Tel Aviv Medical Center, and coauthors. “However, in the current study we meticulously adjusted the association with meat for other nutritional and lifestyle parameters to minimize confounding as much as possible.”
There was also a significant association between unhealthy cooking methods such as frying, broiling, and grilling – which are known to increase the quantity of heterocyclic amines (HCA) in the meat – and insulin resistance.
Individuals who ate one or more portions of meat cooked by these methods showed a higher incidence of insulin resistance compared with those who ate fewer than one portion per week (36.00% vs. 22.20%, P = .004). Researchers also used the food-frequency questionnaires to calculate the quantity of participants’ HCA intake, and found a significantly higher odds of insulin resistance in individuals whose HCA intake was above the median.