Black grapes are full of powerful antioxidants. As a result, their health benefits range from managing diabetes to reducing cancer risk. This article discusses the benefits of black grapes, their nutritional profile, how to use them for maximum benefits, and any potential side effects. Take a look.

How Are Black Grapes Beneficial?

Grapes come in different types – green, red, blue, and black. All varieties contain similar beneficial compounds. Of these, the darker variants seem to be more beneficial (1). Black grapes are comparatively richer in antioxidants. They contain fiber too. Their skin is rich in phenolic acids, like caffeic acid. These compounds are responsible for the fruit’s anti-inflammatory, anticancer, cardioprotective, and antidiabetic properties (2). The most important compound in black grapes (and grapes, in general) is resveratrol. Resveratrol is a potent antioxidant that is extensively studied. Research states that it can fight inflammation, prevent heart disease, and even combat tumors (3). The best way to enjoy the benefits of black grapes is to eat them as a whole (or even by consuming whole-grape products). The beneficial constituents in such whole-grape products can enhance the overall results (4). In the following section, we will discuss how you can benefit from the various constituents of black grapes.

What Are The Health Benefits Of Black Grapes?

Black grapes are chock-full of antioxidants like resveratrol, flavonoids, and quercetin that regulate diabetes, promote heart health, and even prevent cancer. These fruits also combat inflammation and other associated ailments. 

1. May Help Manage Diabetes

The resveratrol in black grapes may improve insulin sensitivity. This can enhance your body’s ability to use glucose, thereby lowering blood sugar levels (5). The compound also increases the number of glucose receptors on cell membranes. This may also help regulate your blood sugar levels (6). More importantly, grapes, in general, have a mean glycemic index. Studies show that diets low in GI improve diabetes symptoms. The resveratrol in grapes also improves the functioning of pancreatic beta cells (cells that make insulin, a hormone that controls glucose levels) (7). Pterostilbene, another compound in grapes, also helps lower blood sugar levels. Black grapes also prevent the loss of beta cells, which is a common complication in diabetes.

2. May Promote Heart Health

The polyphenols in black grapes fight free radicals, which can cause heart disease. These compounds help treat hypertension and inflammation. They also improve endothelial (of the blood vessels) function (8). Black grapes contain flavonoids, phenolic acids, and resveratrol – all of which can reduce cardiovascular mortality (9). These compounds also have anti-platelet effects. They prevent the aggregation of platelets (the clumping of platelets, forming a clot), thereby preventing strokes or heart attacks (9). The potassium in grapes also promotes heart health.

3. May Prevent Cancer

The effect of grapes (in general) on cancer prevention is widely researched. The beneficial compounds in grapes were found to prevent various forms of cancer (10). One such compound that deserves attention is resveratrol. It is more abundant in the skin of black grapes. This compound neutralizes reactive oxygen species. It also induces apoptosis (cancer cell death) and prevents cancer from spreading (11). Resveratrol demonstrated anticancer properties against cancers of the colon, breast, prostate, and the lungs (11). This compound can supplement conservative cancer treatments (as chemo- and radiotherapy). The seeds of black grapes contain proanthocyanidins, other beneficial compounds known to fight cancer (12). Other powerful anticancer constituents in grapes include quercetin, catechin, and anthocyanins (13).

4. May Improve Brain Function

The resveratrol in black grapes has a role to play here as well. Intake of resveratrol can improve mood dysfunction and prevent age-related memory loss (14). Grapes also contain riboflavin, which could be beneficial for individuals with migraines. Some rat studies show the efficacy of resveratrol in preventing Alzheimer’s (15). We need more studies to confirm this in humans, though.

5. Promote Vision Health

Studies show people living in the Mediterranean basin tend to have fewer rates of cataracts than other aging populations. The diets of these populations include grapes and wine – so we can make a connection (16). Black grapes (and grapes, in general) fight free radicals and make the eye lens more resistant to aging (16). An antioxidant-rich diet, well begun at a young age, can dramatically reduce the risk of age-related vision issues. Black grapes contain lutein and zeaxanthin, which are carotenoids that are known to help maintain good eyesight. According to a mouse study published in Nutrition, a diet containing grapes provides significant protection to the retina by shielding against oxidative stress (17). It can also prevent blindness. Grapes have the ability to prevent loss of vision and macular degeneration caused by aging. Studies and research were conducted in this light, and they concluded that having grapes every day reduces chances of developing ARMD or age-related macular degeneration by more than 30%. The antioxidants in grapes, especially the flavanoids, eliminate the harmful effects of free radicals. Free radicals can cause eye-related disorders like cataracts.

6. May Strengthen Bones

The resveratrol in the grapes may improve bone mineral density (18). The effects were observed only in rats, though. We need more human studies to corroborate this fact.

7. May Fight Inflammation

Black grapes contain various important compounds that fight inflammation. These include flavans, anthocyanins, flavonols, and stilbenes (19). Black grapes also work well in treating inflammatory arthritis. The resveratrol works as good as NSAIDS (non-steroidal anti-inflammatory drugs) (20). Black grapes may also aid hemorrhoid treatment. This condition is also called piles, and it occurs when the veins around the anus become inflamed and swollen. The flavonols in black grapes can maintain the integrity of the veins. They also strengthen your veins, thereby relieving symptoms of hemorrhoids (21).

8. May Aid Sleep

There is very little research on this. Grapes, in general, are good sources of melatonin (the sleep hormone) (22). Eating black grapes right before sleeping may improve sleep quality.

9. May Promote Longevity

In various animal species, resveratrol had shown to lengthen lifespan. This compound in black grapes stimulates a family of proteins called sirtuins. Sirtuins are linked to longevity (23). Resveratrol also mimics the beneficial effects of calorie restriction, and this, in turn, might promote longevity (24). Though they are small fruits, their benefits are immense. A lot of research is being done on antioxidants and how they benefit human health. Black grapes are among the richest sources of antioxidants. We saw some of the important constituents of black grapes. In the following section, we will take a look at the other compounds in black grapes that make them a must-have in your kitchen.

What Is The Nutritional Profile Of Black Grapes?

Source: USDA After going through all of this information, eating black grapes seems like a no-brainer. Consuming these fruits is simple and easy. Pop them into your mouth, one after the other. But if you are craving for some variety, we have some suggestions for you.

How To Include Black Grapes In Your Diet

The best way to eat black grapes is fresh. Try to avoid grape jellies or jams as they have added sugars and may not be as beneficial. The following pointers should give you some ideas:

Freeze grapes and have them as a dessert/snack on a hot day. Add whole black grapes to your breakfast smoothie. Slice black grapes and add them to your chicken salad. Add whole black grapes to a fruit salad. Drink 100% grape juice (along with the fiber).

Black grapes are easy to eat. There is no reason you shouldn’t include them in your diet. Or is there?

Do Black Grapes Have Any Side Effects?

Black grapes are generally safe for most people. But some individuals need to exercise caution.

Issues During Pregnancy And Lactation

This has more to do with supplements. The safety of supplements containing resveratrol during pregnancy and lactation has not been established (3). However, it is better you exercise caution with black grapes too as they are among the richest sources of resveratrol. Please consult your doctor.

May Cause Bleeding Issues

We have seen that the compounds in black grapes can have anti-platelet effects. They work against the formation of blood clots (9). This can increase bleeding in susceptible individuals. Though there are no reports of severe bleeding in humans, please take care. Talk to your doctor if you have any specific bleeding issues. Also, stop the intake of grapes at least two weeks before a scheduled surgery. How to buy the right black grapes? Ensure the grapes you pick are firm and plump. They should not have wrinkles. Avoid wet, shriveled, or moldy grapes. Can we eat black grapes at night? Yes. They contain melatonin and may boost sleep quality. Are black grapes good for hair growth? Possibly. Animal studies show that grape seeds contain proanthocyanidins that may promote hair growth (25). However, more studies on humans are warranted. Are black grapes high in sugar? Yes, black grapes are high in natural sugar. However, they are low in calories. Are black grapes good for high blood pressure? Yes, grapes are good sources of potassium that helps lower blood pressure (26).

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