The Nutrition and Health Benefits of Red Grapes

Grapes have been cultivated for thousands of years and they are technically classified as botanical berries.

Red grapes not only make for a healthful snack on their own, but they also make a tasty addition to smoothies, salads and desserts.

The nutritional content for red grapes (and red seedless grapes) is what you'd expect from a sweet fruit.

Red grapes are relatively low in calories and are fat- and cholesterol-free. A 1-cup serving (151 grams) of red grapes has:

• 104 calories
• 0 g fat
• 27 g carbs
  • 1.4 g fiber
  • 23.4 g sugar
• 1 g protein

Some people wonder, do grapes have protein? With only 1 gram per cup, grapes are low in protein. The calories in grapes mostly come from sugar (a type of carb).

One cup of red grapes also offers:

• Vitamin C: 5% of the Daily Value (DV)
• Vitamin K: 18% DV
• Thiamine: 9% DV
• Riboflavin: 8% DV
• Vitamin B6: 8% DV
• Potassium: 6% DV
  
• Magnesium: 3% DV

We can attribute the health benefits of eating grapes to their vitamin and mineral content.

Seedless or not, red grapes are a source of vitamin C: One serving contains 4.8 milligrams of vitamin C, which is about 5 percent DV, based on a 2,000-calorie diet.

Grapes are high in vitamin K, a fat-soluble vitamin that is stored in your body's fat tissues and liver. Your body needs adequate vitamin K to build strong bones and to synthesize several of the proteins required for blood coagulation. If your diet lacks foods rich in vitamin K, you may be more likely to develop osteoporosis or bleed too much when injured, according to the National Institutes of Health (NIH).

Although vitamin K deficiency is rare, people taking antibiotics may experience a mild deficiency, which can lead to excessive bleeding. Each 1-cup serving of red grapes contains 18 percent of the DV.

Other vitamins in grapes include B vitamins such as vitamin B6, riboflavin and thiamine. Your body needs B vitamins to make energy from the food you eat and form red blood cells, according to the U.S. National Library of Medicine.

Red grapes also contain small amounts of vitamin E, vitamin A and beta-carotene. These nutrients help your body processes function properly, and many vitamins, such as vitamin A, have antioxidant properties.

Red grapes are also rich in several minerals. One serving contains 288 milligrams of potassium, 10.6 milligrams of magnesium and 0.5 milligrams of iron. This means that a single serving has 6 percent DV of potassium, 3 percent DV of magnesium and 3 percent DV of iron. Red grapes also contain small amounts of calcium, zinc and selenium.

Another benefit of eating grapes: Red grapes contain resveratrol, which is a polyphenol antioxidant that seems to have anti-inflammatory properties. This antioxidant is concentrated in the skins of red grapes (not green grapes).

A 1-cup serving of red grapes contains about 0.24 to 1.25 milligrams of resveratrol, per Oregon State University.

Preliminary studies link resveratrol to the prevention and/or treatment of cancer, heart disease and neurodegenerative diseases.

To get the most flavorful red grapes with the highest concentrations of antioxidants and nutrients, always pick those that are fully ripe, which look plump and free of wrinkles. They should be firmly attached to a healthy stem and not leaking any juice.

The primary way to predict sweetness of grapes is via color. Red grapes should be deep red in color for most sweetness, although sweetness also varies according to species. Red grape varieties known for sweetness include emperor, cardinal, monukka and globe.

If you buy some red grapes from the grocer and find they are not sweet enough for your palate, let them ripen a day or two more on the vine. Unlike some other fruits, grapes will not ripen any further once removed from the vine.