Tomato sauce: a centimetre of waist and a mould question

In 11 randomised trials, tomato foods and tomato-based products trimmed waist circumference by about 1.2 cm in adults with a mean BMI of 25 or higher (MD -1.153 cm, 95% CI -2.27 to -0.04), with no consistent change in body weight or BMI. That interval almost touches zero, and the tomato interventions were not standardised from trial to trial, so the centimetre is the upper edge of something small. It is still the firmest result on this page. The prostate reputation rests on weaker ground. Among 47,894 US male health professionals followed from 1986 to 1992, the men eating more than 10 weekly servings of tomato foods had 35% lower prostate cancer risk than men eating fewer than 1.5 (RR 0.65, 95% CI 0.44-0.95). Intake there came from a food-frequency questionnaire that counted sauce together with tomatoes, juice and pizza, so the sauce itself was never isolated, and a cohort of this kind shows association rather than effect. Whether processed tomato matches fresh tomato has no yes or no answer yet. Twelve laboratory papers on industrial processing point in different directions depending on the method and the compound, and their authors write that the available data are not sufficient.

What your body absorbs

• Eating fat together with a carotenoid-rich food raises carotenoid absorption, and unsaturated fat raises it roughly three times as much as saturated fat (SMD 0.90 against 0.27). — healthy adults in 12 randomised controlled trials, plus 27 in vitro digestion studies analysed separately (n = 12 RCTs) Evidence A source
  SMD 0.90 (95% CI 0.69-1.11) for unsaturated fat against SMD 0.27 (95% CI 0.08-0.47) for saturated fat
• GABA from pureed tomato reached the blood as well as GABA dissolved in water, while glutamate from the tomato matrix peaked later (0.98 h against 0.41 h) and about half as high. — 11 healthy men, randomised cross-over, four drinks of 1 litre each a week apart, 18 blood samples over 24 hours (n = 11) Evidence B source
  Glutamate tmax 0.98 h against 0.41 h (P = 0.003); Cmax 7815 against 16 420 ng/mL (P = 0.006)

What cooking and storage change

• Industrial processing moves tomato nutrients in different directions depending on the method, and only 12 original studies have measured it. — 12 original research papers on industrial processing of tomatoes, with USDA SR Legacy used for the composition estimates (n = 12 studies) Evidence D source
  Direction of change differs by processing method and by compound

What it does to your health

• Tomato foods and tomato-based products trimmed waist circumference by about 1.2 cm in adults with overweight or obesity, with no consistent change in body weight or BMI. — adults with mean BMI 25 kg/m2 or higher, 11 randomised trials inside a review of 47 studies (n = 11 RCTs) Evidence A source
  Waist circumference MD -1.153 cm (95% CI -2.27 to -0.04)
• Men who ate more than 10 weekly servings of tomato foods, tomato sauce among them, had 35% lower prostate cancer risk than men who ate fewer than 1.5 servings. — 47,894 US male health professionals free of cancer in 1986, followed to 1992, with 773 non-stage A1 prostate cancers (n = 47894) Evidence C source
  Multivariate RR 0.65 (95% CI 0.44-0.95) for more than 10 against fewer than 1.5 servings per week

Safety, limits and interactions

• Tomatoes are among the foods most often carrying Alternaria mycotoxins, and modelled intake of tenuazonic acid in children sits close to the tolerable daily intake. — food and feed surveys and national dietary exposure assessments published in English from 2011 to 2024 Evidence C source
  Children's dietary exposure to tenuazonic acid close to the tolerable daily intake
• The European Commission set indicative levels for processed tomato products at 10 ug/kg alternariol, 5 ug/kg alternariol monomethyl ether and 500 ug/kg tenuazonic acid, above which the source of the contamination has to be investigated. — food business operators and member states monitoring Alternaria toxins in the EU Evidence E source
  Processed tomato products: AOH 10 ug/kg, AME 5 ug/kg, TeA 500 ug/kg

What people believe that the data does not support

• The EU register lists the claim that tomato pulp and sauces are an almost unique source of lycopene as non-authorised, so it may not be used on a label in the EU. — — Evidence E source
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Who this works differently for

• Korean men in the top fifth of tomato intake had 14% lower risk of prehypertension, and women in the top fifth 6%, which the authors describe as a similar trend. — Korean adults of the Health Examinees cohort, tomato intake by food-frequency questionnaire, split into quintiles (n = cohort size not given in the abstract) Evidence C source
  HR 0.86 (95% CI 0.80, 0.92) in men; HR 0.94 (95% CI 0.90, 0.99) in women

What is still unknown

• Nutrition science still has no yes or no answer to whether processed tomato products match fresh tomatoes, because the data on processing effects are too thin. — 12 original research papers on industrial processing of tomatoes (n = 12 studies) Evidence D source
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The bottom line

The kitchen rule about eating tomato with oil is supported for carotenoids in general and not for lycopene in particular. A meta-analysis of 12 randomised trials in healthy adults found carotenoid absorption rose with more dietary fat. Unsaturated fat raised it about three times as much as saturated fat (SMD 0.90, 95% CI 0.69-1.11 against SMD 0.27, 95% CI 0.08-0.47), in trials built on mixed carotenoid sources and not on tomato sauce. Lycopene was the one carotenoid whose bioaccessibility did not rise with fat in the in vitro work analysed alongside those trials. Oil in the pan remains a reasonable habit. Treat it as taste rather than as a measured lycopene tactic. Two cautions remain: one about what is in the jar, one about what is on the label. Tomatoes are among the foods most often carrying Alternaria mycotoxins. A 2025 review of occurrence and exposure studies modelled intake of tenuazonic acid in children from the whole diet as close to the tolerable daily intake, not from tomato sauce alone, and that exposure was estimated from contamination surveys rather than measured in people. These toxins are stable to heat, so cooking does not take them out. The European Commission set indicative monitoring levels for processed tomato products at 10 ug/kg alternariol, 5 ug/kg alternariol monomethyl ether and 500 ug/kg tenuazonic acid, a threshold that triggers an investigation of the source and not a withdrawal. The claim that tomato pulp and sauces are an almost unique source of lycopene is listed as non-authorised in the EU register, so it may not appear on a label there. We found no evidence card on pregnancy, allergy or medicines for tomato sauce, and that silence is a gap in what we looked at, not an all-clear. People differ. In a Korean cohort, men in the top fifth of tomato intake had 14% lower risk of prehypertension and women 6% (HR 0.86, 95% CI 0.80-0.92 in men, HR 0.94, 95% CI 0.90-0.99 in women). Both figures come from fresh tomato intake in Korea, with no subgroup for sauce reported. Underweight people and drinkers showed no reduction at all. This cohort has no USDA composition row in our set, so there is no per-100 g table above.

Sources

1. tsauce-daily-r3-02 · systematic review and meta-analysis
   The meta-analysis of RCTs showed that the bioavailability of carotenoids was enhanced when a higher quantity of dietary fats was co-consumed. Moreover, fats rich in unsaturated fatty acids resulted in greater improvement in carotenoid bioavailability (SMD 0.90; 95%CI, 0.69-1.11) as compared with fats rich in saturated fatty acids (SMD 0.27; 95%CI, 0.08-0.47).
   Nutr Rev, 2022 · checked 2026-09-24
2. tsauce-daily-r3-08 · randomised controlled trial
   GABA from pureed tomatoes showed similar bioavailability to that of a solution in water. For glutamate, the absorption from pureed tomatoes occurred more slowly as seen from a longer tmax (0.98 ± 0.14 h vs. 0.41 ± 0.04 h, P = 0.003) and lower Cmax (7815 ± 627 ng mL-1vs. 16 420 ± 2778 ng mL-1, P = 0.006).
   Food Funct, 2022 · checked 2026-09-24
3. tsauce-daily-r3-09 · scoping review
   Twelve original research papers were found to study the effects of different industrial processing methods on the nutrients and/or bioactive compounds in tomato products. The data suggested that different processing methods had different effects on different compounds in tomatoes. However, currently available data are still limited, and the existing data are often inconsistent.
   Adv Nutr, 2022 · checked 2026-09-24
4. tsauce-daily-r3-01 · 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 2026-09-24
5. tsauce-daily-r3-03 · cohort study
   Combined intake of tomatoes, tomato sauce, tomato juice, and pizza (which accounted for 82% of lycopene intake) was inversely associated with risk of prostate cancer (multivariate RR = 0.65; 95% CI = 0.44-0.95, for consumption frequency greater than 10 versus less than 1.5 servings per week; P for trend = .01)
   J Natl Cancer Inst, 1995 · checked 2026-09-24
6. tsauce-daily-r3-05 · systematic literature review
   Alternaria mycotoxins are widely present in various food and feed products, with tomatoes and cereals being the most contaminated products...The calculations and risk values suggest that exposure of children to TeA via their diet is close to their tolerable daily intake.
   Compr Rev Food Sci Food Saf, 2025 · checked 2026-09-24
7. tsauce-daily-r3-06 · regulatory recommendation
   Indicative level for alternariol, alternariol monomethyl ether and tenuazonic acid in certain foods, based on the available data in the EFSA database, above which investigations should be performed, on the factors leading to the presence of Alternaria toxins or on the effect of food processing.
   Commission Recommendation (EU) 2022/553 on monitoring the presence of Alternaria toxins in food, 2022 · checked 2026-09-24
8. tsauce-daily-r3-07 · health claim register
   POL-HC-7535 Lycopenes from tomato pulp and sauces Tomato is as almost unique as a source of a specific carotene named: Lycopene; Therefore use it always is any conditions for its nutritional qualities Non-authorised
   EU Register on nutrition and health claims, claim POL-HC-7535, snapshot 2026-09-21 · checked 2026-09-24
9. tsauce-daily-r3-04 · cohort study
   Higher tomato consumption was associated with a lower risk of prehypertension in men (hazard ratio (HR) 0·86, 95 % CI 0·80, 0·92, Pfor trend 0·0005). Women in the highest quintile also showed a similar trend (HR 0·94, 95 % CI 0·90, 0·99, Pfor trend 0·0091).
   Br J Nutr, 2026 · checked 2026-09-24
10. tsauce-daily-r3-10 · scoping review
    At this point, we do not have sufficient data to fully understand all of the factors and their impacts.
    Adv Nutr, 2022 · checked 2026-09-24