Eating grapes decreases cholesterol levels which may help prevent heart attacks and strokes, a new study suggests.
Researchers in California gave participants 46 grams per day of whole grape powder, providing the equivalent of two servings of California table grapes.
Consuming grapes significantly increased the diversity of bacteria in the gut, which is considered essential to a strong immune system, the experts found.
Additionally, eating grapes significantly decreased levels of cholesterol, the fat found in our blood that can clog up the arteries and lead to heart diseases.
Consuming grapes also reduced levels of bile acid, which are essential in the processing and metabolisation of cholesterol.
Grapes, apples and other fruit like them are rich in antioxidants known as polyphenols. – organic compounds naturally present in plants – which keep blood vessels healthy and flexible for good circulation.
Polyphenols and other ‘phytochemicals’ can also reduce and help control blood sugar levels and blood pressure levels, and reduce chronic inflammation, another risk factor for heart disease.
Grape consumption benefits gut microbiome and cholesterol metabolism, researchers in California report (stock image)
The new study was led by Zhaoping Li, a nutritionist and professor of medicine at the University of California, Los Angeles, and published in the journal Nutrients.
Professor Li stated that “we found grapes to have a beneficial impact on gut bacteria.” This is great news since healthy gut is essential for good health.
“This research deepens and broadens our understanding of grapes’ health benefits, as well as enhancing the benefits to the heart from grapes that have lower cholesterol.
For the study, the experts analysed the microbiota – the trillion-strong community of microorganisms – of centenarians based on their stool samples.
Microbiota is also known as the microbiome – although this latter term includes the collective genomes of the microorganisms in a particular environment, as well as the microorganisms themselves.
In total, 19 healthy subjects consumed a low-polyphenol and low-fibre diet for four weeks.
The grape powder was continued for four more weeks. They received 46 grams per day of grape extract over the course of four weeks.
Before and after the supplementation, stool and urine samples were taken.
CVD is the general name for any condition that affects blood vessels or the heart. Cardiovascular disease (CVD) includes strokes and heart disease. While all cardiovascular diseases include heart disease, some heart conditions are not heart disease. Stock image
Four weeks of grape drinking led to an increase in the microbial diversity, measured using Shannon index (a widely used instrument for measuring species diversity).
Akkermansia is a beneficial bacteria found in increased numbers. It’s a fascinating bacteria because it has a beneficial effect both on glucose and on lipid metabolism.
A decrease in total cholesterol and LDL cholesterol (low-density cholesterol) was also observed.
Bile acids – steroid acids which are linked to cholesterol metabolism – decreased by 40.9 per cent, they found.
According to the researchers, the findings indicate a new role for grapes and strengthen the health benefits of grapes for heart health.
Research has shown that grape consumption in all forms of wine can have heart health benefits.
The improvement in heart health has been shown to be linked to grapes of all kinds, such as powders or red wines (pictured).
Researchers in Germany and Northern Ireland discovered that drinking three glasses of red wine, each 125ml per week, lowers blood pressure.
According to the team, another type of phytochemical called flavonoids – the abundant nutrients in fruits, vegetables, tea and other plant-based foods – appear to have a positive effect on blood pressure levels.
Microorganisms that make up the billion-strong microorganism family in our gut (known as the microbiota) are responsible for breaking down flavonoids.
Researchers at the University of Michigan studied the impact of regular grapes on laboratory rats. This was done in 2010 as part of the high-fat American diet.
The three-month-old rats with grape-enriched diets had lower blood pressure, better function in their hearts, and less inflammation than the ones who did not receive grape powder.