A Detailed Guide to Eating Grapes and Reaping Their Possible Health Benefits

They’re nutritious, sweet as candy, and have been essential to the good life since the dawn of civilization. Served in fresh bunches, in dried snack-friendly nuggets or with their essence squeezed and fermented into intoxicating elixirs, grapes take on various forms to satisfy our appetites. Read on to learn more about them.

What Are Grapes and Where Do They Come From?

Grape plants, fruit-bearing vines from the Vitis genus of the Vitaceae family, have been with us so long that fossilized leaves, stems, and seeds have been found in Northern hemisphere deposits from the Neogene and Paleogene periods, which cover a stretch of time between 2.6 million and 65 million years ago. Their colorful globe-like, juicy, sugary berries are what we call grapes, whether they come in blue, purple, red, pink, green, or amber. (1)

Grape cultivation began as early as 6,500 B.C. Propelled by winemaking — the fermentation of grape juice into an alcoholic beverage — by 4,000 B.C., cultivation had spread from Eastern Europe and Western Asia into the Nile delta region, after which the practice moved westward into Europe and eastward into China. (2,3) Grape wine was so important to the ancient Greeks and Romans that they worshipped a god of wine and pleasure, whom they called Dionysus and Bacchus, respectively. (4)

After the fall of the Roman Empire, the role of wine in the Christian mass helped grape cultivation flourish in Europe. The practice crossed the Atlantic with the European colonization of the Americas. (5) Today, Italy, France, and the United States are the world’s top producers of grapes. (6)

Grapes are nutrition powerhouses. They are packed with vitamin C, a powerful antioxidant that plays key roles in immune system health, connective tissue development, and wound healing. (7,8) They’re also a source of vitamin K, which helps with blood clotting and maintaining healthy bones; as well as potassium, which is important kidney and heart function, muscle contraction, and nerve signal transmission. (9,10)

Grapes are also rich in antioxidants, which help protect the body’s cells against oxidative stress, a mechanism linked to cancer, heart disease, and Alzheimer’s disease. In particular, darker grapes, such as Concord and purple varieties, are especially high in antioxidants, according to an article published in December 2013 in the journal Antioxidants. (11) Grapes are the perfect addition to your 1.5 to 2 cups of recommended daily fruit intake, per the U.S. Department of Agriculture's MyPlate guidelines.

According to the Department of Agriculture (USDA), these are the nutrition facts for 1 cup of red or green grapes, or 151 grams (g): (12)

Calories: 104

Protein: 1.09g (2.18 percent daily value, or DV)

Total fat: 0.24g

Carbohydrate: 27.33g

Total dietary fiber: 1.4g (5.6 percent DV)

Sugars: 23.37g

Potassium: 288 milligrams (mg) (6.13 percent DV)

Vitamin C: 4.8mg (8 percent DV)

Vitamin K: 22 micrograms (27.5 percent DV)

The fruit, seeds, skins, and leaves of grape plants (Vitis vinifera) are purported to have many health benefits — some supported by research, and many more for which there is insufficient evidence, according to the Natural Medicines Comprehensive Database (NMCD). (13)

Here are some the supposed health benefits for which the NMCD says there is evidence that grape products are ineffective:

• Hay fever
• Nausea and vomiting caused by chemotherapy
• Tissue hardness and pain caused by radiation
• Weight loss

Research so far has turned up insufficient evidence of effectiveness for the following health benefits of grape products, although in many cases, early research holds promise, according to the NMCD:

• Age-related mental decline
• Athletic performance
• Diabetic retinopathy (eye damage)
• High cholesterol
• Melasma (patches of darker skin on the face)
• Premenstrual syndrome
• Heavy menstrual bleeding
• Menopausal symptoms
• Muscle soreness
• Poor night vision
• Nonalcoholic fatty liver disease
• Wound healing
• Age-related macular degeneration
• Attention deficit-hyperactivity disorder (ADHD)
• Canker sores
• Chronic fatigue syndrome
• Constipation
• Soothing cough (attributed to raisins)
• Diarrhea
• Hemorrhoids
• Liver damage
• Varicose veins

Nonetheless, according to the NMCD, grape seed and grape leaf extracts are possibly effective for addressing symptoms of poor blood flow in the legs (chronic venous insufficiency); and grape seed extract may relieve eye stress from glare. (13)

A deeper dive into additional health claims that the NMCD cites reveals the following:

Grapes May Lower Blood Pressure and Boost Heart Health

Although the NMCD notes there’s insufficient evidence that grapes can improve heart health and lower blood pressure, research so far suggests there may be promise. For example, a systematic review of randomized, controlled human trials that was published in Journal of the American Dietetic Association found that a variation of grapes, grape seed extract, lowered participants’ systolic blood pressure (the pressure in the blood vessels when the heart beats) and heart rate. But the authors wrote that the extract has no effect on cholesterol or diastolic blood pressure. They called for larger studies over a longer period of time to confirm grape seed’s contribution to cardiovascular health. (14,15)

A subsequent review of randomized, controlled human trial published in August 2016 in the journal Medicine saw a beneficial impact on blood pressure, particularly in young and obese adults, and likewise called for larger, long-term studies of the extract. (16)

But of course, neither of these studies involved whole grapes, so don’t go eating them to improve heart health just yet.

Grapes May Help Lower the Risk of Type 2 Diabetes

Eating whole grapes may help lower the risk of developing type 2 diabetes. A long-term study of over 190,000 healthy individuals published in August 2013 in the journal BMJ concluded that eating more blueberries, grapes, and apples is “significantly associated” with a lower risk of developing the condition. (17)

Blueberries, darker grapes, and apples are all rich in the pigment anthocyanin, a flavonoid with antioxidant properties. Additionally, grapes have a medium glycemic load (a measure of food’s ability to raise blood glucose) of 11 per serving. (18,19) Eaten in moderation, they can be part of a healthy diet that can help keep blood sugar under control.

A Glass of Prevention? What the Benefits of Grape Suggest About Wine

What about all of the hype around red wine being heart-healthy? Large studies looking at whether wine drinkers were at lower risk of cardiovascular disease than beer or liquor drinkers have come to varying conclusions, so the jury is still out.

Some studies have focused on the presence of resveratrol, an antioxidant compound that is present in wine, as well as red grape skins and juice. Yet a cohort study published in July 2014 in the journal JAMA Internal Medicine, which looked at 783 people over age 65 who lived in Tuscany, Italy, and consumed a resveratrol-rich diet, found no link between the presence of the compound in their urine and rates of heart disease, cancer, and death. (20) Furthermore, there isn’t much evidence that ingesting resveratrol has much of an antioxidant effect inside of the human body either. (21)

Eating grapes may give you an edge in the battle of the bulge. The 2016 BMJ article reported on a long-term cohort study of 124,086 men and women ages 27 to 65 who were followed for up to 24 years. Those people who upped their intake of certain types of flavonoids, including anthocyanin, gained less weight than those who did not. (17)

Plus, as sweet-tasting as grapes are, 10 of them will set you back only 34 calories and 9g of carbohydrates — 2 and 3 percent, respectively, of your daily value based on a 2,000 calorie, 300g of carbs per day, diet. They make a great, fiber-rich substitute for a junk food snack or sugary drink. (12,22)

Because grapes contain vitamin K, they may affect the way that blood thinners, such as Coumadin or Jantoven (warfarin), work in your body. You should not avoid grapes and other foods rich in vitamin K, but rather try to keep your intake of vitamin K about the same each day. You should also communicate with your doctor about your eating habits — and any supplements you are taking, such as grape seed extract — if you’re on blood thinner medication. (23,24)

There are approximately 8,000 varieties of grape grown across the globe. Among the most popular kinds are:

The European grape (V. vinifera), which is the kind most commonly used in wine-making. From albariño to zinfandel, the varietals from which our favorite wines are fermented run the gamut of colors, shapes, and flavors. Many popular table grapes, including the Thompson seedless (the bestselling grape in the United States), are also variations of V. vinifera. (2)

The fox grape (V. labrusca) is native to North America. Generally, its varieties are lower in sugar content and higher in acid than European grapes. The most popular variety of V. labrusca is the Concord grape. Blue-back in color, with an in-your-face sweetness, Concord grapes make fabulous jellies, jams, juices (think Welch’s), and kosher wines. (2,25)

French-American hybrids came about because European grapes are on the delicate side, unable to withstand weather extremes and susceptible to diseases. French grapes, in particular, have been hybridized with hardier American grapes to form varietals such as chardonel and vidal blanc; and in some cases French varietals such as merlot and pinot noir have been grafted onto disease-resistant American rootstock. (2,26)

The muscadine grape (V. rotundifolia) is a species from the American South that is known by its small, thick-skinned berries and musky flavor. It is made into juices, jellies, and dessert wines. (2,27)

What about Oregon Grapes?

Oregon grapes are not to be confused with any of the aforementioned plants, because they are not actually grapes at all. Instead of belonging to the Vitis genus, Oregon grapes belong to the unrelated Mahonia genus in the barberry family (Berberidaceae) of evergreen shrubs. Still, their blue-black berries do cluster like grapes, and can be made into jellies. (28,29)

Growing grapes at home takes patience and commitment, as you’ll be cultivating and tending to the vines and harvests for a number of years. They can live up to a century, or even longer. (30)

To get started, choose a warm site protected from high winds that gets at least six to eight hours of sunlight per day. Construct a trellis or arbor before planting so the vines will have a support structure to train them to grow upward. Buy one-year-old plants that are suitable to your local climate and geography from a reputable nursery, preferably ones that are certified to be virus-free. You can find tips on what to do next at the Old Farmer’s Almanac and SFGate’s Home Guides. (30,31)

When selecting grapes at the store or farmer’s market, look for bunches that have green, pliable stems and plump, firm berries. Don’t worry if they have a white, powdery coating on them. That’s “bloom,” which offers natural protection against decay. But if they are soft, puckered, or brown in appearance, they are probably heading toward rot or raisin territory. (32)

Store unwashed grapes dry in the refrigerator and then rinse them thoroughly before eating them. They’ll keep on your counter about three to five days, in the refrigerator 5 to 10 days, and in the freezer three to five months. (32,33) Freezing then brings out the sweetness, and they make a great frozen snack for a hot summer day, or a healthy alternative to juice pops for children (cut them in half for those ages 5 and under).

Grapes are versatile! They make great wine, juices, vinegars, jellies, jams, and raisins. Their leaves make great wraps for rice and other tasty fillings. You can:

• Use your oven to dry grapes into raisins.
• Make your own muscadine wine.
• Cook up and can a batch of Concord jelly.
• Better yet, turn wine to vinegar and liven your salads.
• And don’t forget to preserve the grape leaves!

Even if you’re in less of a DIY mood, there are plenty of other ways to enjoy grapes in side dishes, mains, and desserts.

Grape Recipes

• Toss up a Mixed Greens With Grapes and Feta salad to kick off a hot-weather meal.
• Indulge in both sweet and savory with Pan-Seared Pork Chops With Roasted Grapes.
• Taste the rainbow for a healthy dessert: Rainbow Fruit Salad.
• Bake a delicious loaf of Carrot Raisin Bread.
• Or go for a guilty pleasure and whip up Raisin-Pumpkin Custard.