Contents
What it is
The tomato is the fruit of a nightshade, a relative of potato, aubergine and chilli. It originated in the Andes of South America and was domesticated in Mexico. Botanically it is a fruit, since it carries the seeds, but it is low in sugar and high in savoury depth, so cooking treats it as a vegetable — the glutamate it holds is exactly why it underpins so many sauces and broths. The red comes from lycopene, a fat-soluble pigment, which is why heating it with oil raises absorption. Refrigeration dulls the aroma.
Scientific name Solanum lycopersicum
Most vegetables lose nutrients when heated. Tomatoes are the exception. Lycopene sits locked inside cell walls, so little of it is absorbed from a raw tomato.
Cooking breaks those walls down and converts lycopene into a more absorbable form. That is why tomato sauce and paste outperform fresh tomatoes on lycopene uptake.
Key benefits
- Nutrition data
Lycopene is a powerful antioxidant
The carotenoid behind the red colour measures higher than beta-carotene in free-radical scavenging capacity. Observational studies repeatedly find lower cardiovascular risk among people with higher blood lycopene.
- Early research
Prostate health is its most studied association
Several cohort studies report lower prostate cancer incidence where more tomato products are eaten, with a dose-response relationship. But all of this is observational. A systematic review of trials that actually gave people lycopene concluded the evidence was insufficient to draw a firm conclusion. It is the most consistently repeated observation — but an observation is an observation.[1][2]
- Nutrition data
Potassium helps excrete sodium
237 mg per 100 g at just 18 kcal. You can eat a lot without energy cost, which makes tomatoes a practical potassium source in a salty diet.
- Early research
It may add to your skin's UV resistance
Small trials found less UV-induced redness after ten or more weeks of eating tomato paste. It does not replace sunscreen.[3]
How to eat it well
- Cook them in oil. Lycopene is fat-soluble and heat-stable; sautéing in olive oil raises absorption substantially.
- Processed forms are a genuinely good choice. Tomato paste and canned tomatoes are more concentrated in lycopene than fresh.
- Keep the skin on. Lycopene concentrates near it.
- Refrigeration ruins the flavour. Cold damages the aroma compounds, so store at room temperature and cook them.
- Riper means more lycopene. The redder, the better.
How to read the grades
Each benefit carries a label showing how far research on people supports it. Grades differ between items even within the same ingredient.
- Nutrition data
- A fact verifiable from food composition databases or health authorities. This is a different kind of statement from a clinical effect.
- Strong evidence
- Consistently confirmed across randomised controlled trials or meta-analyses.
- Moderate evidence
- Human studies exist, but effect sizes are small or results are mixed.
- Early research
- Cell or animal work, or small preliminary studies.
- Not established
- Commonly claimed, but not confirmed in studies on people.
What to watch out for
- With acid reflux, the acidity can worsen symptoms.
- Tomatoes are nightshades, and related allergic reactions occur rarely.
- Very large intakes sustained over months can turn skin orange (lycopenemia). It is harmless and reversible.
- Many commercial tomato juices and sauces are high in sodium — check the label.
Nutrition
Approximate values per 100 g edible portion.
- Calories
- 18 kcal<1%
- Carbohydrates
- 3.9 g1%
- Fiber
- 1.2 g4%
- Sugars
- 2.6 g
- Protein
- 0.9 g2%
- Lycopene
- 2,573 µg
- Vitamin A
- 42 µg5%
- Vitamin C
- 14 mg16%
- Potassium
- 237 mg5%
Percentages are of the US FDA Daily Value for adults and children 4 and over. National reference intakes differ by sex and age.
Calculate this alongside other ingredients →
Key nutrients
Dishes with this ingredient
- Chicken breast and avocado salad25 min
- Lentil and tomato soup35 min
- Sardine and tomato toast10 min
- Baked trout with broccoli25 min
- Herring braised in tomato30 min
- Chickpea and kale stew30 min
- Coconut chickpea curry30 min
- Boiled soybean and tomato salad25 min
- Quail egg and spinach salad15 min
- Mussels in tomato25 min
- Artichoke and chickpea salad20 min
- Olive and tomato salad10 min
- Black bean and green pea salad15 min
- Okra, tomato and egg stir-fry12 min
Sources
The databases and health authorities this article's nutrition figures and health statements draw on.
- 1Lycopene and Risk of Prostate Cancer: A Systematic Review and Meta-AnalysisMeta-analysisChen P, et al. Medicine (Baltimore) 2015PMID 26287411
- 2Is there a benefit from lycopene supplementation in men with prostate cancer? A systematic reviewSystematic reviewsHaseen F, et al. Prostate Cancer Prostatic Dis 2009PMID 19901932
- 3Tomato Phytonutrients Balance UV Response: Results from a Double-Blind, Randomized, Placebo-Controlled StudyClinical trialGroten K, et al. Skin Pharmacol Physiol 2019PMID 30836363
- 4USDA FoodData CentralFood composition database
- 5NIH Office of Dietary SupplementsHealth authority
- 6PubMedResearch literature
