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Tomato
Caution🐾Tomate · (Solanum lycopersicum)
Nightshade family (Solanaceae)
Description
Botanically a berry, the bright red, juicy fruit of this annual plant from the nightshade family (Solanaceae) is among the most widely eaten vegetables worldwide. Ripe fruits contain the red carotenoid lycopene, beta-carotene, vitamin C, potassium and organic acids such as citric and malic acid. Clinical trials have examined regular consumption of ripe tomatoes for cardiovascular health and immune function. In the kitchen, tomatoes are eaten raw, cooked or used as a spice paste; in folk use, sliced tomato is also applied to soothe irritated skin. IMPORTANT: green, unripe fruit, leaves and stems contain the glycoalkaloid tomatine and should not be eaten raw in larger amounts — they can cause nausea and gastrointestinal upset. Fully ripe red fruit, by contrast, contains only negligible alkaloid traces and is considered safe; people with histamine intolerance may react sensitively.
Raw ripe tomato fruits supply lycopene (potent carotenoid antioxidant), vitamin C, vitamin K, potassium and dietary fibre. Clinical studies and EFSA opinions confirm the nutritional relevance of these nutrients for oxidative stress, immune function and cardiovascular health. Lycopene is better absorbed from heated tomato products (paste, sauce) than from raw fruit.
Tomato paste, puree and cooked sauces (passata) are culinary preparations in which lycopene bioavailability is substantially improved by heat processing and co-presence of fat (olive oil). Foundation of Mediterranean cuisine (sofrito, sugo) — these cooked preparations are nutritionally superior to raw tomato juice in terms of lycopene uptake.
Regular tomato consumption is associated with reduced cardiovascular disease risk in epidemiological studies, attributed to the combined effect of lycopene, potassium, folate and phenolic acids. The EFSA panel confirms the evidence chain for lycopene antioxidant activity; however, direct clinical endpoints remain insufficient per EFSA 2011 for an approved product-level health claim.
In folk medicine, tomato slices were applied topically to sunburn and minor skin irritations — the mild acidity (citric and malic acid) and lycopene are considered cooling and soothing. This folk application is not clinically validated; however, the photoprotective effect of oral lycopene intake is the subject of clinical investigation.
In European folk medicine, tomatoes (fresh juice, raw fruit) were used for urinary complaints and considered mildly diuretic food. Their high water content (~95 %) and potassium content support renal flushing. Specific clinical evidence is lacking; the dietary use of potassium-rich vegetables is nutritionally recognised.
Dried tomatoes (oven-dried, sott'olio) are a traditional preservation product of southern Italian and Spanish cuisine. Water removal concentrates lycopene, glutamic acid (umami), sugars and minerals strongly — dried tomatoes have approximately 10-fold higher lycopene content per unit weight than fresh fruit.
Tomato juice and freshly pressed tomato products (gazpacho, cold soups) are a traditional vegetable intake form in the Mediterranean diet. Tomato juice contains significant amounts of lycopene, vitamin C, potassium and organic acids, and is in this context part of WHO-recommended Mediterranean dietary patterns.
Green, unripe tomato fruits and all green plant parts (leaves, stems, unripe fruits) contain tomatine (a steroid glycoalkaloid) and traces of solanine — toxic raw in larger amounts (nausea, GI upset, headache). Fully ripe red fruits are safe with only negligible alkaloid traces. Persons with histamine intolerance or IBS may react sensitively to tomatoes (histamine release, acid irritation). Cross-reaction possible in known nightshade (Solanaceae) allergy. ASPCA classification (accessed 2026-08-10): toxic to dogs and cats — the toxic parts are the leaves, stems and unripe green fruit, while small amounts of ripe tomato flesh are considered harmless. The ASPCA classifies the whole genus this way.
Ripe tomatoes are safe and nutritionally valuable in normal dietary amounts during pregnancy and lactation (folate, vitamin C, potassium). Avoid green fruits and plant parts.
Ripe tomatoes in dietary amounts are safe. If the infant shows colicky reactions, temporarily omit tomatoes from the maternal diet and observe.
Ripe tomatoes safe from weaning age (approx. 6 months). Green fruits and plant parts must be strictly avoided for children — lower body mass increases poisoning risk from tomatine/solanine.
Drug interactions
Antazida und Protonenpumpenhemmer (PPI)
Tomatoes and tomato juice are acidic (pH ~4, citric and malic acid) and can worsen symptoms in persons with reflux or peptic ulcer. No pharmacological interaction in the strict sense, but a dietary interaction that may affect medication requirements.
Antikoagulanzien (Warfarin, Phenprocoumon)
Tomatoes contain vitamin K1 (phylloquinone, ~7–8 µg/100 g fresh). Strongly fluctuating tomato consumption may minimally affect INR values in patients on vitamin K antagonists. The vitamin K content is very low compared to leafy greens (spinach, kale) — clinically rarely relevant, but consistency of intake is recommended.
Contraindications
- Hypersensitivity to tomatoes or other Solanaceae — cross-allergy with potato, pepper, aubergine possible.
- Severe gastro-oesophageal reflux disease (GERD) or peptic ulcer: tomato juice and products may worsen complaints due to high acidity — monitor individual tolerance.
- Diagnosed histamine intolerance: tomatoes are high in histamine and can trigger complaints (flush, headache, GI symptoms) — limit or avoid.
Harvested part: ripe fruits (summer-autumn)
- Time of day:
- Harvest preferably in the morning after dew has dried — fruits are then cool and firm. Evening-harvested tomatoes may have more intense aroma after sun exposure but are warmer and deteriorate more quickly.
- Drying:
- Tomato plants fruit in a staggered progression over several weeks — not all fruits ripen simultaneously. Check ripeness daily or every 2 days. Fully ripe fruits: uniformly red (or variety-specific yellow, orange, black), slight give under finger pressure, easy detachment from stem with a gentle twist. Store unripe or cracked fruits separately. Green tomatoes for pickling or chutney must be cooked — never consumed raw in large quantities. Do not refrigerate fresh tomatoes (flavour loss below 12 °C) — store dark at 15–20 °C for up to 5 days. For drying: halve fully ripe fruits, scoop out seeds, dry at 60–70 °C in a dehydrator or oven (door slightly ajar) for 8–12 hours until leathery.
- Storage:
- 1 months
- Time of day:
- Seed saving from fully ripe, over-ripe fruits — ideally from vigorous, healthy plants of favourite varieties (seed multiplication). Harvest in dry weather.
- Drying:
- Scoop seeds from fully ripe fruits, ferment in a glass of water with surrounding gel at room temperature for 2–3 days (remove mould surface layer, decant seeds). Good seeds sink. Wash with clean water, spread on baking paper and dry fully at room temperature for 1–2 weeks. Store cool, dark, dry in labelled paper bags or jars — viability up to 4–5 years.
- Storage:
- 48 months
- LycopinOtherContent: 0,002–0,02 %Fruit
Red carotenoid, lead compound of the tomato. Ripe red tomatoes contain 2–20 mg/100 g fresh weight, concentration varies strongly with variety and ripeness. Among the most potent natural antioxidants. Bioavailability from heated products (paste, sauce) with fat is substantially higher than from raw fruit (heat converts all-trans to cis isomers, improving absorption). EFSA rejected an antioxidant-related health claim in 2011 but acknowledges the substance evidence.
- Beta-CarotinOtherContent: 0,0003–0,0006 %Fruit
Provitamin A (beta-carotene) in small amounts (~0.3–0.6 mg/100 g). Converted to retinol (vitamin A) in the body. Significantly lower than lycopene in red tomatoes; orange and yellow varieties have higher beta-carotene relative to lycopene.
- Ascorbinsäure (Vitamin C)VitaminContent: 0,012–0,023 %Fruit
12–23 mg/100 g fresh weight — covers approximately 20–30 % of daily requirements (EFSA: 80 mg/day adults) with 150 g tomato. Water-soluble and heat-sensitive: cooking reduces content significantly. Important for immune function, collagen synthesis and as antioxidant cofactor.
- Vitamin K1 (Phylloquinon)VitaminContent: 0,000007–0,000009 %Fruit
7–9 µg/100 g fresh weight. Important for blood coagulation and bone metabolism. Content significantly lower than in leafy greens (spinach: ~450 µg/100 g). Relevant for patients on vitamin K antagonists (warfarin) only with very excessive tomato consumption.
- KaliumMineralContent: 0,237 %Fruit
Approx. 237 mg/100 g fresh weight — relevant potassium source within a vegetable-rich diet. Potassium supports normal muscle function, nerve conduction and contributes to normal blood pressure maintenance (EFSA-confirmed claim). Content 10-fold concentrated in tomato paste.
- Zitronensäure und Apfelsäure (organische Säuren)OtherContent: 0,4–0,7 %Fruit
Primarily responsible for the pH (~4.0–4.5) and characteristic tart flavour of ripe tomatoes. Citric acid dominates (~0.3–0.5 %), malic acid in lesser amounts. These organic acids make tomato products problematic for persons with GERD or histamine intolerance.
- Tomatinidin-Glykoalkaloid Tomatin (in unreifen Früchten und Kraut)AlkaloidContent: 0,001–0,05 % (Grünfrucht)Fruit
Tomatine (alpha-tomatine) is a steroidal glycoalkaloid occurring in relevant amounts in unripe green fruits, leaves and stems (up to 50 mg/100 g in leaves). Degraded to trace levels (<5 mg/100 g) in fully ripe red fruits. Responsible for the toxicity of green tomatoes (nausea, GI complaints, rarely neurological symptoms at high doses). Cooking reduces tomatine only minimally.
- Nahrungsfasern (Dietary Fibre, überwiegend unlöslich)PolysaccharideContent: 1,2 %Fruit
Approx. 1.2 g/100 g fresh weight. Predominantly insoluble fibre (cellulose, hemicellulose in skin and pomace). Supports intestinal transit and microbiome. Tomato products with pomace (passata) have higher fibre content than tomato juice without pomace.
- [1]MonographEFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) — Scientific Opinion on the substantiation of health claims related to lycopene (2011), EFSA Journal 9(4):2031(accessed: 2026-05-21)
- [2]MonographEFSA NDA Panel — Scientific Opinion on Dietary Reference Values for potassium (2016), EFSA Journal 14(10):4592(accessed: 2026-05-21)
- [3]MonographUSDA FoodData Central — Tomatoes, red, ripe, raw, year round average (FDC ID: 170457)(accessed: 2026-05-21)
- [4]MonographPlants For A Future (PFAF) — Solanum lycopersicum database entry(accessed: 2026-05-21)
- [7]MonographASPCA Animal Poison Control — Deadly Nightshade (Solanum spp)(accessed: 2026-08-10)
- [5]WikipediaTomate (Wikipedia DE)(accessed: 2026-05-21)
- [6]WikipediaTomato (Wikipedia EN)(accessed: 2026-05-21)
🤝 Permaculture Partners
In your garden, this plant acts as:
✨ Best symbiotic partners
- 🌿 Onion Classic companion-planting partner.
- 🌿 Garlic Classic: garlic in every tomato bed — deters mildew.
- 🌿 Chives Chives deter aphids from tomatoes and attract bees for pollination.
- 🌿 Apium graveolens Celery scent masks tomato from pests.
- 🌿 Calendula officinalis Calendula attracts beneficials and deters nematodes.
- 🌿 Basil Traditional pairing; that basil improves tomato flavour is untested. A mixture including basil showed no demonstrated extra whitefly control on greenhouse tomatoes compared with French marigold; basil alone was not tested (Conboy et al. 2019).
- 🌿 Parsley Parsley attracts lacewings that eat aphids.
- 🌿 Parsley Classic companion-planting partner.
- 🌿 Tagetes patula Marigold roots deter nematodes in the tomato bed. Study: with French marigolds among greenhouse tomatoes from the start, whitefly was clearly lower from day 34; added to a heavy infestation later, they had little effect (Conboy et al. 2019).
- 🌿 Tropaeolum majus Nasturtium pulls aphids away from tomato (trap plant).
⚠️ Better not planted together
- 🥬 Cabbage Tomato and cabbage compete heavily for nitrogen.
- 🥬 Red cabbage Classic companion-planting partner.
- 🥬 Broccoli Classic companion-planting partner.
- 🥬 Cucumber Tomato and cucumber share fungal disease (mildew) — cross-infection.
- 🥬 Fennel Fennel strongly inhibits tomato growth (allelopathic).
- 🥬 Potato Both Solanaceae — late blight transfers between them.
📦 Part of these planting sets:
Source: Conboy et al., PLOS ONE 14(3):e0213071 (2019) — Tagetes gegen Weiße Fliege an Gewächshaustomaten (Studie) | Gertrud Franck, Gesunder Garten durch Mischkultur (1980, eigene Kuration) | Helga und Margarete Langerhorst, Mein gesunder Naturgarten (eigene Kuration)