I’d written a while back about a relationship between eating a high fat diet and risk of diabetes. This is an interesting topic and one might wonder why the two should be linked together. There has been some work on this, notably Chiang et al. 2010) who investigated two different types of high fat diet along with a low fat diet using mice. cause by experimenting with mice. The one of the high fat diets contained fresh soybean oil while the other used oil that had been subjected to high heat and was heavily oxidized (think deep-fried food oil).
|Map by the CDC|
The mice fed high oxidized frying oil exhibited reduced insulin secretion and high blood glucose levels. Very important here: their islets of Langerhans (the tissue that produces insulin, as well as glucagon) showed evidence of oxidative damage. Glucagon and insulin work together to keep blood sugar stable. It seems likely that oxidative damage would occur throughout the body, so its probably best to avoid fried food. Interestingly, regions in the US where frying in oil is common practice are also regions with high prevalence of diabetes. This area (the Southeastern US) has been referred to as “the diabetes belt.”
It was also interesting that mice fed the high fat diet made with fresh soybean oil did not show such changes. This implies that a diet high in fried food may put people at risk of diabetes or metabolic disorder by interfering with production of hormones regulating blood sugar, while a high fat diet of unoxidized oil might be just fine. Vitamin E is an important anti-oxidant and is protective against the effects of High Oxidized Frying Oil. Chiang et al. found that adding Vitamin E to the diet reduced the effects of the Oxidized Fat diet.
Chiang YF, Shaw HM, Yang MF, Huang CY, Hsieh CH, & Chao PM (2011). Dietary oxidised frying oil causes oxidative damage of pancreatic islets and impairment of insulin secretion, effects associated with vitamin E deficiency. The British journal of nutrition, 105 (9), 1311-9 PMID: 21205372