Could eating a bunch of grapes help to fight high blood pressure related to a salty diet? Could they also calm other factors that are also related to heart diseases such as failure of the heart? You'd be amazed at what those oval rounds of goodness have packed inside their black, red or green skin.
A new study conducted by the University of Michigan Cardiovascular Center gives tantalizing clues to the potential of grapes in reducing the risk of cardiovascular complications. The effect is thought to be due to the high level of phytochemicals, which are naturally occurring antioxidants that grapes contain.
The current study was performed on laboratory rats. The researchers studied the effects that regular table grapes (a blend of black, green and red grapes) that were mixed into the rat diet in a powdered form, as part of either a diet low in salt or a diet high in salt. The researchers then performed many comparisons between the rats that were consuming the test diet and the control rats that were receiving no grape powder—including some that had received a mild dose of a common blood pressure medication. All of the rats were from a research breed that is prone to developing high blood pressure when they are fed a salty diet.
Mitchell Seymour, M.S., who lead the research as part of his doctoral work in nutrition science at the Michigan State University, said that in all, after 18 weeks, the rats that had received the diet with the grape-powder had reduced inflammation in their bodies, lower blood pressure, better heart function, and fewer signs of heart muscle damage that the rats that had eaten the same salty diet but did not receive any grapes. The rats that received the blood pressure pill, hydrazine, along with the salty diet also had lower blood pressure, but their hearts were not protected from damage as the rats in the grape-fed group. "These findings support out theory that something within the grapes themselves has a direct impact on cardiovascular risk, beyond the simple blood pressure-lowering impact that we already know can come from a diet rich in fruits and vegetables."
Steve Bolling, M.D., who is a professor of cardiac surgery at the U-M Medical School, notes that the rats in the study were in a put in a similar situation as millions of Americans, who have suffered from high blood pressure related to their diet, and who develop heart failure over time because of the prolonged hypertension. He also stated that the inevitable downhill sequence from hypertension to heart failure was changed by adding the grape powder to a high salt diet. Bolling explained, " Although there are many natural compounds in the grape powder itself that may have an effect, the things that we think are having an effect against the hypertension may be the flavanoids—either by direct antioxidant effects, by indirect effects on cell function, or both. These flavanoids are rich in all parts of the grape—skin, flesh, seed, all of which were in our powder."
Although the current study was supported in part by the California Table Grape Commission, which also supplied the researchers with the grape powder, the authors note that the commission played no role in the design of the study, analysis, conduct, or preparation of the journal article for publication. Seymour has also received funding from the National Heart, Lung, and Blood institute, which is part of the National Institutes of Health, through a National Research Science Award.
This does not mean it is time to tell patients to throw all of their medication away and just eat grapes. However, the research on the grapes and other fruits that contain high levels of antioxidant phytochemicals continues to show promise. So does the research on the impact of red wine on the heath of the heart, though that issue is also far from being settled.
Bolling suggested that if people wish to lower their blood pressure, reduce the risk of having heart failure, or help their weakened hearts retain as much pumping power as possible should follow tried-and-true advice: Cut down on the amount of salt that you get through your drink and food. "There is, as we know, a great variability, perhaps genetic even, in sensitivity to salt and causing hypertension. Some people are very sensitive to salt intake, some are only moderately so, and there are perhaps some people who are salt resistant. But in general we say stay away from excess salt."
He also notes that the popular DASH diet, which is low in salt and high in vegetables and fruits, has been proven to reduce mild high blood pressure without taking any medications. The dose of whole table grape powder that was consumed in the new study was roughly equivalent to a person eating nine human-sized servings of grapes daily. Currently, five to nine servings of vegetables and fruits are recommended as part of the Dash diet plan.
In all, the researchers say that this study demonstrates that a diet enriched with grapes can have broad effects on the development of hypertension and the risk factor that come along with it. Whether the effect can be replicated on humans, the researchers say, remains yet to be seen.
http://www.healthnews.com/nutrition-diet/grapes-newest-heart-healthy-food-2044.html
