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Study analysis · Atherosclerosis · 2017

Eating tomatoes can lower your bad cholesterol by 0.22 mmol/L—but lycopene alone might not be the magic bullet.

A review of 21 studies found that eating tomatoes can improve cholesterol, inflammation, and blood vessel function, while lycopene supplements lower blood pressure.

Reading level
Very low certainty
Level 1a · Systematic review of RCTsAssociation, not causationNo causal claims

Overview

What the study found

The study in plain English — the bottom line, every takeaway we extracted, and what to do with them.

In simple terms

This study looked at many smaller studies where people ate tomatoes or took lycopene pills to see if it helped their heart health. Because the studies might not have been the strongest type (like a blind test with a placebo), we can't say for sure that tomatoes cause these improvements – they might be linked, but we need more proof.

What’s the bottom line?

Researchers looked at 21 studies to see if eating tomatoes or taking lycopene helps heart health. They found that tomatoes can lower bad cholesterol and inflammation, and improve blood vessel function. Lycopene can lower blood pressure.

How strong is this study?

The researchers did a good job by gathering lots of studies and combining their results, which gives us a bigger picture. But we only have a short summary of their work, and we don't know if the individual studies were done well or if some were biased. So we need to be careful about trusting the results completely.

Reporting

0 / 100

  • COI disclosureconflicts of interest not disclosed
  • Data availabilitydata not shared
  • Code availabilitycode not shared
Methodology

0 / 100

  • Randomizationrandomization unclear
  • Blindingblinding unclear
  • Control groupno control group
  • Sample sizeno sample size reported
  • Follow-upno follow-up reported
Publication

100 / 100

Statistical

54 / 100

  • P-values+15/15
  • Effect size+20/20
  • Confidence intervalsno confidence intervals
  • Pre-registrationnot pre-registered

Each component is scored out of 100 and then capped by the study design — a case series cannot reach the ceiling a randomised trial can, however well it is reported.

Where it sits

RCT reviews

Max 100

Randomized Trials

Max 90

Reviews of Cohort Studies

Max 85

Cohort Studies

Max 72

Reviews of Case-Control Studies

Max 63

Case-Control Studies

Max 58

Cross-Sectional & Case Series

Max 50

Expert Opinion

Max 5
StrongerWeaker
Reviews of RCTs (Meta-analyses)
Level 1a
33

33 / 100

Probability of being correct

The highest quality evidence. Systematic reviews and meta-analyses that pool randomized controlled trials, giving the most reliable summary of experimental evidence.

This design cannot establish causation — the findings describe an association, not a cause. The systematic review included intervention trials but it does not specify whether they were randomized controlled trials. Without clear evidence of randomization, causal inference is limited. Additionally, meta-analysis combines heterogeneous studies, and the abstract does not provide details on study quality or risk of bias.

COI Unknown

Could not determine conflict of interest status

Not Disclosed

No conflicts of interest or funding information disclosed in the study text.

Undisclosed — Suspicious

The study text does not include any declaration of conflicts of interest, funding sources, or author affiliations. Without this information, it is impossible to determine potential biases.

Key takeaways

  1. 01

    Bad cholesterol down 0.22 mmol/L, inflammation down a bit (standardized mean difference -0.25), blood vessel function up 2.53%, systolic blood pressure down 5.66 mmHg.

  2. 02

    These changes are modest but could help heart health over time.

Surprising findings

  • Lycopene supplements alone did not significantly affect cholesterol, inflammation, or blood vessel function—only whole tomato products did for those markers.Common belief holds that lycopene is the key heart-healthy component of tomatoes. This study suggests that other compounds (e.g., other carotenoids, vitamins, fiber) may be responsible for additional benefits.
  • Tomato supplementation improved FMD by 2.53%, a marker of endothelial function, but did not significantly affect pulse wave velocity (arterial stiffness).Many expect all vascular measures to improve uniformly. This differential effect suggests tomatoes may primarily improve the inner lining function rather than arterial stiffness.

Practical takeaways

Incorporate cooked tomatoes (like tomato sauce, paste, or canned tomatoes) into meals regularly to maximize lycopene absorption and overall heart benefits.

Effects are modest and based on short-term trials; full diet and lifestyle matter more. Full paper not available to verify methodology quality.

low confidence

If you take lycopene supplements, focus on blood pressure benefits (≈5 mmHg reduction) but don't expect significant changes in cholesterol or inflammation.

Lycopene supplements only showed benefit for systolic BP; not all supplements are equal in bioavailability. Full paper not available.

low confidence

Why this study matters

Whole Tomatoes vs. Lycopene: The Synergy Effect

The meta-analysis found that tomato products (not just lycopene) significantly reduced LDL-cholesterol by 0.22 mmol/L and IL-6 (inflammation marker) by a standardized mean difference of -0.25, and improved flow-mediated dilation (FMD) by 2.53%. In contrast, lycopene supplementation only significantly reduced systolic blood pressure by 5.66 mmHg, with no effects on lipids or inflammation. This suggests other compounds in tomatoes may be responsible for the broader benefits.

Many people assume lycopene is the sole active ingredient in tomatoes for heart health. This study shows that whole tomatoes or tomato products may offer more comprehensive benefits than isolated lycopene supplements.

Small Changes, Big Impact?

The reductions observed—0.22 mmol/L in LDL, 2.53% in FMD, and 5.66 mmHg in systolic BP—are modest but clinically meaningful. For context, a 1 mmHg reduction in systolic BP can lower cardiovascular risk by 2-3% at a population level.

Audiences often want quick, dramatic results. Emphasizing that small, consistent dietary changes can accumulate over time makes this actionable and realistic.

Tomatoes and Inflammation: Not Just Cholesterol

Beyond lowering LDL, tomato products reduced IL-6, a key inflammatory marker linked to heart disease. The standardized mean difference of -0.25 is moderate, but it highlights an anti-inflammatory benefit often overlooked in cholesterol-focused discussions.

Inflammation is a hot topic in health. Showing that a common food can help manage inflammation is both surprising and practical.

Want the whole report?

Detailed mode opens the full scientific breakdown — every score component, the methodology, conflicts of interest, the evidence analysis behind each claim, and the raw study data.

Standing

Who’s using this study?

The videos and claims on this site that lean on this study, and the researchers who wrote it.

1 video from Physionic cite this study, drawing 2 claims from it.

Physionic
A Difficult Heart Disease Effect of Tomato based Products
Citing claim
All 1 video reference this study through extracted claims.