Grapes: Nutrients, What Research Shows and Safety

Grapes are the berries of the grapevine, Vitis vinifera, in the grape family (Vitaceae). The whole berry is eaten fresh, dried as raisins, or pressed into juice. People eat grapes for their sweetness, and many ask about the plant pigments in the skin. This page keeps the food apart from supplements (such as grape seed extract or resveratrol pills) and from hype.

Read this first

• A true grape allergy is uncommon but can be severe. Case reports describe anaphylaxis (a sudden, serious allergic reaction) after fresh grapes, raisins or wine. [11] For trouble breathing or swelling of the face or throat, call 911. See food allergy basics and emergency signs.
• Whole grapes are a round, smooth food. The American Academy of Pediatrics describes the shape, size and firmness of some foods as raising choking risk in children aged 3 or younger. [12] Its summary does not name grapes, so ask a pediatrician or your local health service how to prepare them for a small child.
• Grapes contain natural sugar (about 23 g in one cup, USDA). [1] People who count carbohydrates for diabetes should treat the cup as a carbohydrate food.
• Honest summary: large cohort studies link eating grapes with a lower chance of type 2 diabetes, and trials of grape products show small changes in blood pressure and cholesterol. These are weak or low-certainty results, not proof that grapes prevent or treat any disease.

What is in it (USDA values)

Values are for European-type grapes such as Thompson seedless, raw, USDA FoodData Central item 174683, with the USDA household portion of 1 cup (151 g). [1] Per-serving figures are our arithmetic from the USDA per-100 g values. % Daily Value uses the FDA 2016 Daily Values; values vary with variety, ripeness and storage. American slip-skin grapes (such as Concord type, item 174682) are listed separately: 1 cup is 92 g and manganese is 0.72 mg per 100 g (31% Daily Value per 100 g), much higher than in European types. [2]

Grapes are known for polyphenols (plant pigments studied for health effects). The sources we read describe polyphenols from grape products in trials, mostly as juice, extracts or powders rather than the plain fruit. [6][4] Resveratrol, a compound in grape skins, has been tested as a capsule; see the table below. USDA also lists small amounts of lutein plus zeaxanthin (72 µg per 100 g). [1] We did not read a source that measures the amounts of polyphenols in a cup of grapes, so we give none.

What research says

Eaten as food vs taken as a supplement or extract. The cohort result is about everyday fruit. Most trial results are for grape products such as powders, juice, extracts and raisins, and the meta-analyses mix them together. [4][5][6] Grape seed extract and resveratrol are supplements and behave differently from the fruit. NCCIH reports that a 2022 review found grape seed extract lowered diastolic but not systolic blood pressure, and a 2020 review suggested effects on LDL and triglycerides, from small studies with products that varied. [8] A result for one form does not transfer to another.

How much is a normal serving

• The USDA household portion for European-type grapes is 1 cup (151 g), about 104 kcal; ten grapes are 49 g. [1] This is information, not a prescription.
• The UK NHS counts 80 g of fresh, canned or frozen fruit as one portion of 5 A Day, and 30 g of dried fruit as one portion. It suggests dried fruit at mealtimes rather than as a between-meal snack because of teeth. [13]
• The NHS limits juice and smoothies to 150 ml a day as one portion and notes even unsweetened juice is sugary. [13] See fruit juice vs whole fruit.
• We did not find a read source on how cooking or drying changes grape nutrients, and the USDA file we used has no raisin values: Proper evidence not found in the sources we read.

Safety, allergy and medicines

• Allergy: a German case report describes severe anaphylaxis after fresh and cooked grapes, raisins and wine, traced to a grape protein called a lipid transfer protein. The authors say this type of allergy can happen without pollen allergy. [11] Anyone who has reacted should see an allergist and not test themselves.
• Choking in young children: the AAP statement on choking says the shape, size and consistency of some foods make them more likely to cause choking, especially in children aged 3 or younger. [12] The abstract we read does not mention grapes by name. Cutting round foods is commonly advised, but we did not read an official source for the exact way to cut grapes, so check with your pediatrician. See foods for babies and toddlers: choking, honey and allergens.
• Sugar and diabetes: about 15.5 g of sugar per 100 g (USDA). [1] The cohort data above do not show harm from whole grapes, but fruit juice was linked to higher risk. [3] See foods for blood sugar control.
• Potassium and kidney disease: a cup has about 288 mg of potassium (6% Daily Value). [1] MedlinePlus notes that with chronic kidney disease the kidneys may not remove extra potassium and that some medicines raise potassium levels. [15] This amount is modest; ask your kidney team what suits you. See foods, kidney disease, potassium and oxalates.
• Medicines: grapes are not grapefruit. We did not find a read source describing a medicine interaction with eating grapes. NCCIH tells people who take medicines to talk to a provider before using grape seed extract; it does not name specific interactions. [8] Grapes contain some vitamin K (18% Daily Value per cup, USDA [1]); we did not read a source on grapes and warfarin, so people on warfarin should ask their prescriber. See foods and medicine interactions.
• Pregnancy and breastfeeding: NCCIH says little is known about grape seed extract in pregnancy or breastfeeding. [8] We did not read a source on eating grapes in pregnancy.
• Dried fruit and teeth: the NHS advises dried fruit at mealtimes to protect teeth. [13]
• Pesticide residues: the USDA Pesticide Data Program reports on residues in grapes, but we could not open the report, so we make no claim. Rinsing is advised by the FDA. [14]

Choosing, storing and food safety

• Rinse grapes under running water before eating; do not use soap or produce wash, and dry with a clean cloth or paper towel. Washing lowers bacteria but does not remove all. [14]
• Keep cut or pre-packaged grapes refrigerated; when buying pre-cut produce choose items that are refrigerated or on ice. [14]
• Throw away grapes that look rotten and cut away bruised parts. [14]

Related pages

• Fruit juice vs whole fruit
• Fresh, frozen and canned produce
• Polyphenols and flavonoids in foods
• Foods for blood sugar control
• Foods and medicine interactions: vitamin K, grapefruit and others
• Foods for babies and toddlers: choking, honey and allergens