Vitamin A and a high-fat diet could lead to a high body mass index.
The National Institutes of Health reports that vitamin A is crucial for immune function, vision, reproduction, and cellular communication. It is also vital for cell growth and differentiation. Like any vitamin, if individuals do not consume enough vitamin A through food sources, a dietary supplement is recommended.
Results from a study presented at the American Physiological Society annual meeting suggest that normal levels of vitamin A, in addition to a high-fat diet, may alter the expression of liver genes that regulate glucose and fat metabolism.
In the study, the authors fed rats a high-fat diet for 8 weeks. One group consumed sufficient amounts of vitamin A, while the other group’s diet lacked the recommended level of the nutrient. Each week, the authors measured the animals’ body mass.
At 6 weeks, the vitamin deficient group was found to have significantly lower body mass compared with the sufficient group, according to the study. This was observed to continue throughout the trial.
Additionally, the authors discovered that fat in the liver and the epididymis was decreased in the group consuming a vitamin A deficient diet.
The expression of the Cytochrome P450 26A1 protein was observed to be high in the sufficient group, according to the study. This liver protein regulates retinoic acid and is involved with metabolizing fat and cholesterol.
The authors also discovered that rats in the sufficient group showed increased expression of genes that control glucose metabolism and insulin signaling.
These findings suggest that vitamin A and a high-fat diet may lead to high body weight in rats, and potentially in humans as well. As body weight increases, so does the risk of insulin resistance and diabetes, according to the study.
Further research is needed to determine how vitamin A may play a role in body weight and related conditions. However, these results provide more evidence that individuals should refrain from consuming a high-fat diet.
"Our study [implies] that we should be careful about vitamin A, especially [in] overweight or obese people," wrote first study author Heqian Kuang.