A study published in the October 2003 issue of the journal Nutrition suggests that grape seed extract could be helpful to prevent the absorption of dietary fat. This could benefit individuals attempting to lose weight or those who need to limit fat consumption for other health reasons. The mechanism for grape seed action was that the grape seed extract inhibited the pancreatic enzyme lipase as well as lipoprotein lipase, an enzyme responsible for the hydrolysis of triglycerides from plasma lipoproteins.
The U.S. researchers tested an extract of crushed grape seeds on pancreatic lipase and lipoprotein lipase activity in vitro. They found that the extract contained lipase inhibitors that act in a dose-dependent manner, meaning that the higher the dose of grape seed, the greater the blocking effect. A one milligram per milliliter concentration of the extract caused an 80 percent inhibition of lipase activity during a five minute incubation period. When lipoprotein lipase activity was tested, the same concentration of grape seed extract elicited a 30 percent inhibition of the enzyme.
In the discussion portion of the study, the researchers state that the effect of grape seed extract may be due to a synergistic action of its flavonoid procyanidins rather than being caused by a single component. They recommend further studies to determine whether grape seed extract may be a weight loss treatment in addition to improving plasma lipid profiles, thus reducing the risk of heart disease.
The currently available prescription drug Orlistat works via lipase inhibition and has been shown to decrease dietary fat absorption in adults by approximately 30 percent. Grape seed extract may prove to be an effective natural alternative.
Moreno D; Inhibitory effects of grape seed extract on lipases. Nutrition, Volume 19, Issue 10, Pages 876-879.