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Tomatoes

Solanum lycopersicum

Also known as Tomato, Beefsteak tomato, Cherry tomato, Plum tomato

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The fruit of a nightshade plant, used culinarily as a vegetable. Its red colour comes from lycopene, which becomes considerably easier to absorb when the fruit is cooked.

Heart HealthCirculationMen's HealthSkin Health

Potential health benefits

Best supported: Moderate

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 lipid profile

Heart Health
Moderate evidence

Pooled analyses of tomato and lycopene trials report small reductions in LDL cholesterol, with results varying by whether whole tomato products or isolated lycopene were used. Individual trials are short and often small.

Moderate evidence. Several human studies point the same way, with real caveats.

3 sources

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

Endothelial function

Circulation
Limited evidence

Evidence is limited for an effect on vascular function. A handful of trials report improved flow-mediated dilation with tomato products or lycopene, mostly in people who already had cardiovascular risk factors.

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.

Prostate health

Men's Health
Limited evidence

Observational data links higher intake of cooked tomato products with lower prostate cancer incidence, but the randomised trials of lycopene that followed have been small and largely inconclusive. Association here is not the same as a demonstrated effect.

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

3 sources

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

Skin photoprotection

Skin Health
Limited evidence

Some small trials report that daily tomato paste over several weeks slightly raises the ultraviolet dose needed to redden skin. The effect is modest, the trials are few, and it is nowhere near a substitute for sunscreen.

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.

Ask about Tomatoes

Ask about Tomatoes

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
Calories18 kcal1%
Protein0.88 g2%
Total fat0.2 g0%
Carbohydrate3.89 g1%
Fibre1.2 g4%
Total sugars2.63 g—
Water94.5 g—
Fats
Saturated fat0.028 g0%
Monounsaturated fat0.031 g—
Polyunsaturated fat0.083 g—
Cholesterol0 mg0%
EPA (omega-3)0 g—
DHA (omega-3)0 g—
DPA (omega-3)0 g—
Linoleic acid (omega-6)0.08 g—
Vitamins
Vitamin A42 µg5%
Vitamin C13.7 mg15%
Vitamin D0 µg0%
Vitamin E0.54 mg4%
Vitamin K7.9 µg7%
Thiamin (B1)0.037 mg3%
Riboflavin (B2)0.019 mg1%
Niacin (B3)0.594 mg4%
Pantothenic acid (B5)0.089 mg2%
Vitamin B60.08 mg5%
Folate15 µg4%
Vitamin B120 µg0%
Choline6.7 mg1%
Minerals
Calcium10 mg1%
Iron0.27 mg2%
Magnesium11 mg3%
Phosphorus24 mg2%
Potassium237 mg5%
Sodium5 mg0%
Zinc0.17 mg2%
Copper0.059 mg7%
Manganese0.114 mg5%
Selenium0 µg0%
Other measured compounds
Beta-carotene449 µg—
Alpha-carotene101 µg—
Lycopene2573 µg—
Lutein + zeaxanthin123 µg—
Caffeine0 mg—
Ash0.5 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: Tomatoes, red, ripe, raw, year round average (USDA FoodData Central, FDC ID 170457).

% 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.

  • cookedIncreases lycopene bioaccessibility

    Heating breaks down cell walls and converts lycopene from its all-trans form to cis isomers that the gut absorbs far more readily. Tomato paste and cooked sauce deliver substantially more absorbable lycopene than raw tomato.

  • with fatIncreases lycopene absorption

    Lycopene is fat-soluble and very poorly absorbed from a fat-free meal. Cooking tomatoes in olive oil, or eating them with another fat source, raises blood lycopene several-fold compared with the same amount eaten without fat.

  • cookedReduces vitamin C

    Prolonged cooking destroys much of the vitamin C in tomatoes, so cooked tomato products trade vitamin C for more available lycopene.

Things to know

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

  • Worth knowing

    The nightshade and arthritis claim

    Tomatoes are widely blamed for joint pain in popular writing about nightshades. Controlled human research does not support a link between nightshade vegetables and arthritis, and eliminating them removes useful foods for no demonstrated benefit.

  • Worth knowing

    Reflux symptoms

    Tomato and tomato-based sauces are among the most commonly self-reported heartburn triggers in gastro-oesophageal reflux disease, because of both acidity and their effect on the lower oesophageal sphincter.

  • Allergy

    Oral allergy and latex cross-reactivity

    Tomato allergy is uncommon but documented, most often as oral symptoms in people sensitised to grass pollen or to natural rubber latex.

  • Worth knowing

    Potassium in concentrated tomato products

    Tomato paste, passata and sun-dried tomatoes concentrate potassium several-fold. That matters in advanced chronic kidney disease, where these products are usually restricted more tightly than fresh tomatoes.