Tomato: the association is strong and the trials find nothing

Across 121 prospective studies covering 108 thousand cancers, people with the most lycopene in their blood had 11 percent less cancer than those with the least. Then 34 randomised trials gave people lycopene and tomato and measured what happened: no change in cholesterol, glucose or blood pressure, only a single oxidation marker moved. That gap is the most useful thing anyone can tell you about tomatoes. Blood lycopene is an excellent marker of eating vegetables and of the life that goes with it, and marking is not the same as causing. The prostate cancer figure, the one tomatoes are famous for, is 0.99.

The numbers, per 100 g

What a real portion looks like

• Tomato interventions took about a centimetre off the waist and left weight and body mass index alone. — 47 studies: 11 randomised controlled trials, 5 epidemiological studies and 31 preclinical studies (n = 47 studies) Evidence A source
  Waist circumference fell 1.153 cm (95% CI -2.27 to -0.04, p = 0.0432) in the trials, with no consistent effect on body weight or BMI; meta-regression showed supplementation type influenced blood pressure outcomes; the authors note the absence of a lycopene dose response

What your body absorbs

• Carotenoids from a salad kept arriving in the blood in larger amounts right up to 32 grams of oil in the dressing. — 12 women (n = 12) Evidence B source
  Across the whole 0 to 32 g range, oil was linearly related to absorption of alpha-carotene, lycopene, phylloquinone and retinyl palmitate; beta-carotene rose linearly to 8 g; lutein and tocopherols rose only to 4 g; absorption of everything was highest at 32 g (p<0.002), and the ranking of individuals was consistent across compounds (p<0.0001)
• Olive oil in tomato juice raised every form of lycopene in the blood, peaking a full day later. — 11 healthy volunteers (n = 11) Evidence B source
  All lycopene isomers rose significantly with oil, peaking at 24 hours; LDL and total cholesterol fell significantly 6 hours after the juice with oil, correlating with the rise in trans-lycopene and 5-cis-lycopene

What it does to your health

• Across 121 cohorts, people with the most lycopene in their blood had a tenth less cancer than those with the least. — 121 prospective studies in the review and 119 in the meta-analysis, with 108574 cancer cases and 10375 deaths over 2 to 32 years of follow-up (n = 108574 cases) Evidence C source
  High against low lycopene intake gave pooled relative risk 0.95 (95% CI 0.92-0.98) and high against low blood lycopene 0.89 (0.84-0.95); each 10 micrograms/dL more blood lycopene gave 5% lower risk; cancer mortality 0.89 for tomato intake, 0.84 for lycopene intake and 0.76 for lycopene levels; prostate cancer 0.99 (0.97-1.00)

What people believe that the data does not support

• When tomato and lycopene were tested in trials instead of observed in populations, nothing moved except one oxidation marker. — 34 studies out of 27438 records screened (n = 34 trials) Evidence A source
  Lycopene significantly lowered malondialdehyde; no significant effect on triglycerides, total cholesterol, LDL, HDL, fasting glucose, systolic or diastolic blood pressure
• Sixteen health claims naming tomato have been filed in Europe and sixteen were refused. — — Evidence E source
  16 register entries name tomato and all 16 carry the status Non-authorised; the example combines blackcurrant seed oil, fish oil, tomato lycopene extract, vitamin C and vitamin E for dry skin

The bottom line

One piece of practical advice does hold up. Carotenoids barely cross out of a salad without fat, and the relationship is linear all the way to 32 grams of oil in the dressing, which is about two and a half tablespoons. With tomato juice, 10 percent olive oil raised every form of lycopene in the blood, peaking a full day later, so the oil and the tomato need to be in the same day rather than the same mouthful. Tomato-based interventions also took about a centimetre off the waist across 11 trials while leaving weight and body mass index alone, and the authors note there was no dose response to lycopene, which points away from the compound the supplements are sold on.

Sources

1. tom-dr-03 · systematic review and meta-analysis
   In the RCTs, tomato-based interventions produced a small but significant reduction in waist circumference (MD: -1.153 cm, 95% CI: -2.27 to -0.04, p = 0.0432), with no consistent effects on body weight or BMI.
   Food Funct, 2026 · checked 2026-09-22
2. tom-dr-04 · controlled feeding dose-response study
   Across the entire 0-32-g range, soybean oil was linearly related to the chylomicron AUC and Cmax values for α-carotene, lycopene, phylloquinone, and retinyl palmitate.
   Am J Clin Nutr, 2017 · checked 2026-09-22
3. tom-dr-05 · randomised controlled crossover feeding trial
   All lycopene isomers increased significantly in subjects consuming TJ with oil, reaching the maximum concentration at 24h.
   Food Chem, 2015 · checked 2026-09-22
4. tom-dr-01 · dose-response meta-analysis of prospective cohort studies
   High intakes and high levels of lycopene compared to low amounts were, respectively, associated with 5% (Pooled RR: 0.95, 95% CI: 0.92-0.98, I2 = 26.4%, p = 0.002) and 11% (Pooled RR: 0.89, 95% CI: 0.84-0.95, I2 = 15.0%, p < 0.001) reduction in overall cancer risk.
   Front Nutr, 2025 · checked 2026-09-22
5. tom-dr-02 · systematic review and meta-analysis of randomised controlled trials
   However, lycopene and tomato consumption did not have significant effects on other cardiovascular risk factors such as triglycerides (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), fasting blood glucose (FBG), systolic blood pressure (SBP), diastolic blood pressure (DBP),
   Curr Pharm Des, 2023 · checked 2026-09-22
6. tom-dr-06 · regulatory register entry
   POL-HC-6257 Combination of blackcurrant seed oil (Ribes nigrum), fish oil, lycopene from tomato (Lycopersicon esculentum) extract, vitamin C and vitamin E Helps to improve dry skin condition -/- Non-authorised
   EU Register on nutrition and health claims, заява POL-HC-6257, знімок 2026-09-21 · checked 2026-09-22