Could soybean oil contribute more to the development of diabetes and obesity than sugar? In a study published in PLOS ONE, mice that were fed a diet high in soybean oil had greater signs of metabolic syndrome compared to those who were fed a diet high in coconut oil or fructose.

Poonamjot Deol, PhD, from the University of California, Riverside, and colleagues fed mice a series of diets containing 40% fat, which is similar to current trends in fat consumption among Americans: one containing coconut oil, one containing half coconut oil and half soybean oil, one containing coconut oil and fructose, and one containing coconut oil, soybean oil, and fructose. All diets contained the same number of calories and there were no significant differences in the amount of food consumed in each of the diets.

RELATED: ‘Thrifty Phenotype’ Leads to Less Weight Loss in Obese

Mice eating the diet with soybean oil showed greater weight gain, fat deposits, fatty liver with signs of injury, diabetes, and insulin resistance compared to those eating the diet high in coconut oil. Mice on the soybean oil diet gained nearly 25% more weight than the mice on the coconut oil diet and 9% more than those on the fructose diet; mice eating the fructose diet gained 12% more than those eating the coconut oil diet. Although the fructose diet caused more negative effects in the kidney and a marked increase in prolapsed rectums, it had less severe metabolic effects compared to soybean oil.

The authors acknowledge that this study did not evaluate the impact of the diets on cardiovascular diseases and that consuming vegetable oils could benefit cardiovascular health, even if it also is linked to a greater risk of obesity and diabetes.

For more information visit