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Grapefruit

Citrus x paradisi

Also known as Pink grapefruit, Ruby red grapefruit, White grapefruit

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A large, bitter-sweet citrus fruit, a hybrid of pomelo and sweet orange. Pink and red varieties owe their colour to lycopene, which white varieties lack.

Blood Sugar & Metabolic HealthHeart HealthWeight Management

Potential health benefits

Best supported: Limited

Ordered by how well the human research supports them — strongest first. A rating describes the state of the evidence, not how impressive the food is. How we rate evidence.

Blood glucose response

Blood Sugar & Metabolic Health
Limited evidence

Evidence is limited for an effect on glucose control. A small number of trials report lower post-meal insulin when grapefruit is eaten before a meal, but the findings have not been reliably repeated.

Limited evidence. Early human work, or mostly lab and animal research.

4 sources

Deep research mode adds each paper’s own conclusion and stated limitations.

Blood lipid profile

Heart Health
Limited evidence

Some trials report modest reductions in total and LDL cholesterol with daily grapefruit, more consistently in people whose lipids were raised to begin with. Trials are short and the effect is small relative to standard lipid-lowering approaches.

Limited evidence. Early human work, or mostly lab and animal research.

2 sources

Deep research mode adds each paper’s own conclusion and stated limitations.

Body composition

Weight Management
Insufficient evidence

The idea that grapefruit has a specific fat-burning property dates to mid-century fad diets and has no dependable human research behind it. Where trials show weight change, it tracks with eating fewer calories overall rather than with anything particular to the fruit.

Insufficient evidence. Not enough human research to say anything useful yet.

4 sources

Deep research mode adds each paper’s own conclusion and stated limitations.

Ask about Grapefruit

Ask about Grapefruit

Answers are written only from the entries on this page — the same nutrients, compounds, claims and citations you can read above. Nothing is added from outside the database, and every answer lists what it was built from.

AI explanations are not switched on for this site, so there is nothing to ask here. Everything above is read straight from the database and does not need them.

Key nutrients

Nutrient content per 100 grams
NutrientAmount% DV
Macronutrients
Calories42 kcal2%
Protein0.77 g2%
Total fat0.14 g0%
Carbohydrate10.7 g4%
Fibre1.6 g6%
Total sugars6.89 g—
Water88.1 g—
Fats
Saturated fat0.021 g0%
Monounsaturated fat0.02 g—
Polyunsaturated fat0.036 g—
Cholesterol0 mg0%
EPA (omega-3)0 g—
DHA (omega-3)0 g—
DPA (omega-3)0 g—
Linoleic acid (omega-6)0.029 g—
Vitamins
Vitamin A58 µg6%
Vitamin C31.2 mg35%
Vitamin D0 µg0%
Vitamin E0.13 mg1%
Vitamin K0 µg0%
Thiamin (B1)0.043 mg4%
Riboflavin (B2)0.031 mg2%
Niacin (B3)0.204 mg1%
Pantothenic acid (B5)0.262 mg5%
Vitamin B60.053 mg3%
Folate13 µg3%
Vitamin B120 µg0%
Choline7.7 mg1%
Minerals
Calcium22 mg2%
Iron0.08 mg0%
Magnesium9 mg2%
Phosphorus18 mg1%
Potassium135 mg3%
Sodium0 mg0%
Zinc0.07 mg1%
Copper0.032 mg4%
Manganese0.022 mg1%
Selenium0.1 µg0%
Other measured compounds
Beta-carotene686 µg—
Alpha-carotene3 µg—
Lycopene1419 µg—
Lutein + zeaxanthin5 µg—
Caffeine0 mg—
Ash0.36 g—

Nutrient values are per 100 g of the USDA reference entry named on this page and vary with variety, growing conditions, storage and preparation.

Source record: Grapefruit, raw, pink and red, all areas (USDA FoodData Central, FDC ID 174673).

% DV uses the FDA Daily Values for adults and children aged 4 and over. A dash means no Daily Value has been established for that nutrient.

Bioactive compounds

Compounds present in meaningful amounts. Presence is banded rather than quantified, because whole-food levels vary enormously with variety, growing conditions, storage and preparation.

How preparation changes things

Only effects with real support are listed. If a preparation method is missing, it is because nothing dependable is documented — not because it makes no difference.

Nothing dependable is recorded about how preparation changes this food’s nutritional properties. Rather than guess, this section stays empty.

Things to know

Allergies, interactions and intake concerns. Every food gets this section — a reference where everything is uniformly good is not a reference.

  • Interaction

    Grapefruit and CYP3A4 drug interactions

    Furanocoumarins in grapefruit irreversibly inhibit intestinal CYP3A4, so drugs cleared by that enzyme reach far higher blood levels than intended. The list includes several statins, notably simvastatin, lovastatin and to a lesser degree atorvastatin, where the added exposure raises the risk of muscle damage; dihydropyridine calcium channel blockers such as felodipine and nifedipine; the immunosuppressants ciclosporin and tacrolimus; some antiarrhythmics including amiodarone; and certain benzodiazepines. The enzyme takes about a day to be replaced, so taking the medicine at a different time of day does not avoid the effect. Anyone on regular medication should check with a pharmacist before making grapefruit a habit.

  • Interaction

    Reduced absorption of other medicines

    Separately from CYP3A4, grapefruit juice inhibits OATP transporters and can sharply reduce absorption of drugs such as fexofenadine and some beta-blockers, making them less effective rather than more.

  • Worth knowing

    Potassium in advanced kidney disease

    Grapefruit and its juice carry meaningful potassium. People with advanced chronic kidney disease or on potassium-retaining medication may be given a specific limit.

  • Worth knowing

    Acidity, enamel and reflux

    Like other citrus, grapefruit is acidic enough to contribute to enamel erosion with frequent exposure and commonly aggravates heartburn in people with reflux.