Grapes are a popular summer fruit, eaten raw, or used to make wine, jam, jelly, juice, raisins, vinegar, and grape seed oil. While many of these may be tasty treats (especially wine), there’s no substitute for the nutritional value of grapes.
Grapes are a good source of vitamin K and manganese, but their levels of other vitamins and minerals are minimal. That doesn’t necessarily mean they aren’t good for you though.
Grapes, especially grape skin, have an important stilbene (a phytonutrient) called resveratrol. Resveratrol has anti-fungal/anti-bacterial properties, and has largely been considered one of the main benefits of grapes (and wine).
Resveratrol is often praised for having longevity effects. The research still isn’t conclusive, but studies have found many potential health benefits from the antioxidative, anti-inflammatory, and cytoprotective actions of resveratrol. Unfortunately, the bioavailability in grapes may not be substantial enough to see actual health benefits in humans (to be determined).
The anti-fungal/anti-bacterial properties found in grape peel are incredibly beneficial. They can help prevent many illnesses including E. coli, and will benefit the overall health of your gut.
Some studies have found significant benefits from grape polyphenols. Everything from preventing metabolic syndrome, lowering blood glucose levels, lipid profiles, blood pressure, as well as heart and liver benefits have all been credited to these polyphenols.
While the polyphenols found in grapes can help lower blood glucose levels, the seeds could help protect the pancreas from inflammation that is damaging to a diabetic pancreas. So, you may want to start swallowing your grape seeds instead of spitting them out (especially if you’re diabetic). However, these benefits aren’t present in grape seed oil as the manufacturing process destroys most of these benefits.
Another great benefit, recently revealed in a study out of the University of Milan found that grapes could produce signals that reduce the formation of cancer cell in the digestive tract. While the study used grape extract, it was at a dose comparable to a normal dietary dose, meaning it’s possible to actually see real health benefits from regular grape consumption.
Concord grapes have been found to be beneficial for older adults with mild cognitive impairment. The antioxidants and anti-inflammatory properties help slow cognitive decline, and can increase neuronal signaling.
As great as the potential health benefits of grapes can be, you still have to be careful. 100g of grapes (a little over 1 cup) have 16g of sugar and only 1g of fibre. This is a significant amount, higher than most fruit. This can make grapes dangerous if you’re eating them on a regular basis in high quantities. You can still eat and enjoy grapes, and there are many health benefits, just eat them in moderation (like you should with any fruit).