Grapes can help counter high fat diets: study

Washington D.C.: Grapes might be just what you need to add to your diet as a recent study has revealed that grape polyphenols can help counter the negative effects of high fat diet.

Grape polyphenols helped offset some of the adverse health consequences of consuming a high fat diet rich in saturated fat, according to two laboratory studies conducted at the University of North Carolina Greensboro.

In the first study, the researchers found that consuming a high butter-fat diet enriched with 3 percent grapes for 11 weeks had a lower percentage of overall body fat and reduced subcutaneous fat deposits.

These reductions in body fat were positively associated with changes in intestinal microbes and health; e.g., increases in some beneficial bacteria, decreases in some less desirable bacterial strains, increases in microbial diversity, and improved gut barrier function.

In the second study which ran for 16 weeks, the researchers used an even higher fat diet with multiple types of saturated fat, including lard, beef tallow, shortening, and butter similar to some Western-type diets.

They investigated the impact of the high fat diet enriched with extracts of either the polyphenol fraction of grapes or the non-polyphenol portion of grapes, as well as the high fat diet plus 5 percent whole grapes. All the high fat experimental diets were matched for sugar type and amount.

The results showed that the high-fat diet combined with grape polyphenols reduced the percentage of body fat, subcutaneous and visceral fat depots, markers of inflammation in the liver and fat depots, and improved glucose tolerance and intestinal barrier function.

While the 5 percent whole grape diet did not improve the metabolic profile in this second study, it did improve markers of intestinal health; e.g., increased microbial diversity and decreased abundance of several deleterious bacteria in the intestinal tract.

"These two studies suggest that grapes and grape polyphenols may help offset a number of the adverse effects of consuming a high fat diet and trigger improvements in intestinal or systemic health," said lead investigator Michael McIntosh. "This is an exciting area of health that merits further study."

The study is published in the Journal of Nutritional Biochemistry.