TUESDAY July 8, 2008 (foodconsumer.org) -- A new French study suggests that trans fat does not increase the risk of insulin sensitivity and diabetes.   The study was conducted in rats and it does not mean that trans fat causes no harm to humans.

The study published in the July issue of the journal of Lipid Research showed that either the industrial trans fat (partially hydrogenated trans fat) and dietary trans fat (from dairy) caused insulin resistance.

Epidemiologic studies indicated chronic consumption of trans fat may alter muscle insulin sensitivity. And other studies have shown otherwise that trans fat like saturated can actually cause problems in the pancreas, leading to increased risk of diabetes.

Anne-Laure Tardy at Univ Clermont 1, UFR Médecine, UMR 1019 Nutrition Humaine, F-63000 Clermont-Ferrand, France and colleagues sought to find some evidence to eliminate the concern about the safety of trans fat.

In their study, the researchers fed Wistar rats a diet enriched with 4 percent of energy from trans fat, either in dairy, industrial or a diet with non-trans fat as control for 8 weeks.

A test known as intraperitoneal glucose tolerance test showed that trans fat did not alter insulin and glucose response.

Further, the researchers found trans fat did not alter mitochondrial oxidative capacity in soleus and tibialis anterior rat muscles compared to the control non-trans fat although trans fat did induce a specific reduction in soleus mitochondrial ATP and superoxide anion production.

They concluded that "dietary trans fat of diary or industrial origin have similar effects and do not impair muscle mitochondrial capacity and insulin sensitivity."

Epidemiologists and nutritionists at Harvard University have early estimated that trans fat is implicated in up to 100,000 deaths in the United States.

Trans fat is unnatural forms of fat and natural human enzymes may not be able to adequately metabolize them potentially leaving them in cells/tissue affecting normal physiology.   Early studies showed trans fat altered pancreatic cells and potentially increased risk of diabetes.

Industrially hydrogenated oils are widely used in food industry and restaurants. Trans fat can also be converted from natural oil in any thermal process such as cooking.   The oils are thermally stable and food prepared with this type of trans fat gives a longer shelf-life and renders a unique flavor and texture.

Source:

http://www.jlr.org/cgi/content/abstract/49/7/1445

For more information on trans fat, read http://en.wikipedia.org/wiki/Trans_fat