Study analysis · Food Science & Nutrition · 2025
Can a natural compound in tomatoes help fight obesity? This study in rats says yes, with dramatic drops in cholesterol and inflammation.
Giving lycopene (from tomatoes) to obese rats for 6 weeks helped them lose weight, improve blood fats, and reduce liver damage.
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 was done on rats, not on people. It shows that a substance called lycopene helped the rats get healthier, but rats are different from humans. So we can't say for sure that it will work the same way in people. Think of it as a clue, not proof.
What’s the bottom line?
Scientists gave a special nutrient called lycopene (found in tomatoes) to rats that were overweight from eating too much fatty food. They found that lycopene helped the rats lose weight, lower bad fats in their blood, and reduce damage to their liver.
How strong is this study?
The study had some good parts, like comparing treated rats to untreated ones. But it didn't pick which rats got the treatment randomly, and they didn't hide which rats got the treatment from the scientists. That means the results might be biased, like if someone knows you got a special treatment, they might see better results even if it's not real. Also, only 10 rats per group is a small number.
40 / 100
- COI disclosure+40/40
- Data availabilitydata not shared
- Code availabilitycode not shared
36 / 100
- Randomizationnot randomized
- Blindingblinding unclear
- Control group+15/15
- Sample size (n=40)+3.6/20
- Follow-up+10/10
100 / 100
23 / 100
- P-values+15/15
- Effect sizeno effect size reported
- 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 reviewsReviews of RCTs (Meta-analyses)
Max 100Randomized TrialsRandomized Trials
Max 90Reviews of Cohort StudiesReviews of Cohort Studies
Max 85Cohort StudiesCohort Studies
Max 72Reviews of Case-Control StudiesReviews of Case-Control Studies
Max 63Case-Control StudiesCase-Control Studies
Max 58Cross-Sectional & Case SeriesCross-Sectional & Case Series
Max 50Expert OpinionExpert Opinion
Max 514 / 100
Probability of being correct
Groups of people are followed over time to see who develops an outcome. Strong for identifying risk factors and associations, but cannot prove causation as firmly as RCTs.
This design cannot establish causation — the findings describe an association, not a cause. Animal study cannot establish causation in humans due to species differences and lack of randomization and blinding.
No Conflicts
No conflicts of interest identified
No conflicts identified.
The study used a high-fat diet supplied by a pharmaceutical firm, but no other industry ties are evident. No conflict of interest declaration was provided.
Key takeaways
- 01
Rats that got extra lycopene lost about 41 grams of weight, their bad cholesterol went down by 73%, and their liver function improved.
- 02
This is a big change for rats, but we don't know yet if it works the same way in people.
Surprising findings
- LDL cholesterol dropped by 73.1% with lycopene supplementation (30 mg/kg) in obese rats.Such a large reduction is usually only seen with potent pharmaceutical drugs, not dietary compounds.
- Inflammatory cytokines TNF-α and IL-6 fell by over 50% (54.1% and 64.9% respectively).This suggests lycopene may have strong anti-inflammatory properties, comparable to some drugs.
Practical takeaways
Incorporate lycopene-rich foods like tomatoes, watermelon, pink grapefruit, and red bell peppers into your diet.
This study used a supplement in rats; human benefits are not yet proven. Also, cooking tomatoes with oil increases lycopene absorption.
Low (animal study, small sample, no human data) confidenceIf considering a lycopene supplement, consult a doctor – typical doses in human studies range from 15-30 mg/day, far lower than the rat equivalent.
High doses may interact with medications or cause side effects; long-term safety unknown.
Medium (based on human evidence from other studies, but not this one) confidenceWhy this study matters
Lycopene Drives Weight Loss in Obese Rats
Rats fed a high-fat diet and given 30 mg/kg of lycopene daily lost an average of 41.28 grams more than untreated obese rats over 6 weeks. Their final body weight was 237.94 g vs 284.12 g.
This suggests lycopene might help manage weight, but it's only been shown in rats so far.
Cholesterol Levels Improved Dramatically
Lycopene lowered total cholesterol by 29.1%, triglycerides by 31.2%, and LDL ('bad' cholesterol) by a whopping 73.1%. HDL ('good' cholesterol) increased by 32.7%.
A 73% drop in LDL is huge – comparable to statin drugs in humans – but this is an animal study.
Liver Health Markers Improved
Liver enzymes ALT, AST, and ALP were significantly reduced (e.g., ALT from 89.17 to 30.34 U/L). Liver biopsies showed less fat accumulation and inflammation.
Obesity often leads to fatty liver disease, so this could be a natural intervention if it works in people.
Inflammation and Oxidative Stress Reduced
Inflammatory markers TNF-α dropped by 54.1% and IL-6 by 64.9%. Oxidative stress marker MDA fell by 23%, while antioxidant enzymes SOD and CAT rose by 68.4% and 47.3%.
Chronic inflammation underlies many diseases, so reducing it with a simple nutrient is exciting.
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.
Overview
What the study found
The study in plain English — the bottom line, every takeaway we extracted, and what to do with them.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Scientists gave a special nutrient called lycopene (found in tomatoes) to rats that were overweight from eating too much fatty food. They found that lycopene helped the rats lose weight, lower bad fats in their blood, and reduce damage to their liver.
Research results
Rats that got extra lycopene lost about 41 grams of weight, their bad cholesterol went down by 73%, and their liver function improved.
What this means - more context
This is a big change for rats, but we don't know yet if it works the same way in people.
Investigate the therapeutic potential of lycopene in mitigating hyperlipidemia-induced metabolic disorders in male rats.
Lycopene supplementation (30 mg/kg daily for 6 weeks) significantly reduced body weight, improved lipid profile, reduced liver enzymes, decreased oxidative stress markers, and lowered inflammatory cytokines in high-fat diet-induced obese rats.
Methods Used
40 male Sprague-Dawley rats divided into four groups: basal diet, HFD, HFD + lycopene 25 mg/kg, HFD + lycopene 30 mg/kg. Treatment for 6 weeks with measurements of body weight, lipid profile, liver enzymes, MDA, SOD, CAT, TNF-α, IL-6, and liver histology.
Main Finding
Lycopene at 30 mg/kg reduced body weight by 41.28 g, total cholesterol by 29.1%, triglycerides by 31.2%, LDL-C by 73.1%, increased HDL-C by 32.7%, reduced ALT, AST, ALP, reduced MDA by 23.0%, increased SOD by 68.4% and CAT by 47.3%, reduced TNF-α by 54.1% and IL-6 by 64.9%, and improved liver histology.
Confidence Level
Moderate: animal study with small sample size (n=10/group), no blinding or randomization reported, but statistically significant results.
Study Flags
Red Flags
- •Small sample size (n=10 per group)
- •No randomization or blinding reported
- •Animal model may not translate to humans
Surprising Findings
LDL cholesterol dropped by 73.1% with lycopene supplementation (30 mg/kg) in obese rats.
Such a large reduction is usually only seen with potent pharmaceutical drugs, not dietary compounds.
Practical Takeaways
Incorporate lycopene-rich foods like tomatoes, watermelon, pink grapefruit, and red bell peppers into your diet.
RCT reviewsReviews of RCTs (Meta-analyses)
Max 100Randomized TrialsRandomized Trials
Max 90Reviews of Cohort StudiesReviews of Cohort Studies
Max 85Cohort StudiesCohort Studies
Max 72Reviews of Case-Control StudiesReviews of Case-Control Studies
Max 63Case-Control StudiesCase-Control Studies
Max 58Cross-Sectional & Case SeriesCross-Sectional & Case Series
Max 50Expert OpinionExpert Opinion
Max 514 / 100
Probability of being correct
Groups of people are followed over time to see who develops an outcome. Strong for identifying risk factors and associations, but cannot prove causation as firmly as RCTs.
Animal Cohort Study
Subject
Lower probability
on the GRADE evidence scale
This study was done on rats, not on people. It shows that a substance called lycopene helped the rats get healthier, but rats are different from humans. So we can't say for sure that it will work the same way in people. Think of it as a clue, not proof.
The study has a COI section but no disclosure was found. A small penalty has been applied.
Strengths
- Controlled study with negative control group
- Two dose levels of lycopene tested
- Multiple outcomes measured (lipid profile, liver enzymes, oxidative stress, histology)
Weaknesses
- No randomization of animals to groups
- No blinding of investigators or outcome assessors
- Small sample size (n=10 per group)
Methodology
Evidence Keywords
Statistical Reporting
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Scientists gave a special nutrient called lycopene (found in tomatoes) to rats that were overweight from eating too much fatty food. They found that lycopene helped the rats lose weight, lower bad fats in their blood, and reduce damage to their liver.
Research results
Rats that got extra lycopene lost about 41 grams of weight, their bad cholesterol went down by 73%, and their liver function improved.
What this means - more context
This is a big change for rats, but we don't know yet if it works the same way in people.
Investigate the therapeutic potential of lycopene in mitigating hyperlipidemia-induced metabolic disorders in male rats.
Lycopene supplementation (30 mg/kg daily for 6 weeks) significantly reduced body weight, improved lipid profile, reduced liver enzymes, decreased oxidative stress markers, and lowered inflammatory cytokines in high-fat diet-induced obese rats.
Methods Used
40 male Sprague-Dawley rats divided into four groups: basal diet, HFD, HFD + lycopene 25 mg/kg, HFD + lycopene 30 mg/kg. Treatment for 6 weeks with measurements of body weight, lipid profile, liver enzymes, MDA, SOD, CAT, TNF-α, IL-6, and liver histology.
Main Finding
Lycopene at 30 mg/kg reduced body weight by 41.28 g, total cholesterol by 29.1%, triglycerides by 31.2%, LDL-C by 73.1%, increased HDL-C by 32.7%, reduced ALT, AST, ALP, reduced MDA by 23.0%, increased SOD by 68.4% and CAT by 47.3%, reduced TNF-α by 54.1% and IL-6 by 64.9%, and improved liver histology.
Confidence Level
Moderate: animal study with small sample size (n=10/group), no blinding or randomization reported, but statistically significant results.
Study Flags
Red Flags
- •Small sample size (n=10 per group)
- •No randomization or blinding reported
- •Animal model may not translate to humans
Surprising Findings
LDL cholesterol dropped by 73.1% with lycopene supplementation (30 mg/kg) in obese rats.
Such a large reduction is usually only seen with potent pharmaceutical drugs, not dietary compounds.
Practical Takeaways
Incorporate lycopene-rich foods like tomatoes, watermelon, pink grapefruit, and red bell peppers into your diet.
RCT reviewsReviews of RCTs (Meta-analyses)
Max 100Randomized TrialsRandomized Trials
Max 90Reviews of Cohort StudiesReviews of Cohort Studies
Max 85Cohort StudiesCohort Studies
Max 72Reviews of Case-Control StudiesReviews of Case-Control Studies
Max 63Case-Control StudiesCase-Control Studies
Max 58Cross-Sectional & Case SeriesCross-Sectional & Case Series
Max 50Expert OpinionExpert Opinion
Max 514 / 100
Probability of being correct
Groups of people are followed over time to see who develops an outcome. Strong for identifying risk factors and associations, but cannot prove causation as firmly as RCTs.
Animal Cohort Study
Subject
Lower probability
on the GRADE evidence scale
This study was done on rats, not on people. It shows that a substance called lycopene helped the rats get healthier, but rats are different from humans. So we can't say for sure that it will work the same way in people. Think of it as a clue, not proof.
The study has a COI section but no disclosure was found. A small penalty has been applied.
Strengths
- Controlled study with negative control group
- Two dose levels of lycopene tested
- Multiple outcomes measured (lipid profile, liver enzymes, oxidative stress, histology)
Weaknesses
- No randomization of animals to groups
- No blinding of investigators or outcome assessors
- Small sample size (n=10 per group)
Methodology
Evidence Keywords
Statistical Reporting
Scoring
How strong is this study?
The study had some good parts, like comparing treated rats to untreated ones. But it didn't pick which rats got the treatment randomly, and they didn't hide which rats got the treatment from the scientists. That means the results might be biased, like if someone knows you got a special treatment, they might see better results even if it's not real. Also, only 10 rats per group is a small number.
40 / 100
- COI disclosure+40/40
- Data availabilitydata not shared
- Code availabilitycode not shared
36 / 100
- Randomizationnot randomized
- Blindingblinding unclear
- Control group+15/15
- Sample size (n=40)+3.6/20
- Follow-up+10/10
100 / 100
23 / 100
- P-values+15/15
- Effect sizeno effect size reported
- 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 reviewsReviews of RCTs (Meta-analyses)
Max 100Randomized TrialsRandomized Trials
Max 90Reviews of Cohort StudiesReviews of Cohort Studies
Max 85Cohort StudiesCohort Studies
Max 72Reviews of Case-Control StudiesReviews of Case-Control Studies
Max 63Case-Control StudiesCase-Control Studies
Max 58Cross-Sectional & Case SeriesCross-Sectional & Case Series
Max 50Expert OpinionExpert Opinion
Max 514 / 100
Probability of being correct
Groups of people are followed over time to see who develops an outcome. Strong for identifying risk factors and associations, but cannot prove causation as firmly as RCTs.
This design cannot establish causation — the findings describe an association, not a cause. Animal study cannot establish causation in humans due to species differences and lack of randomization and blinding.
No Conflicts
No conflicts of interest identified
No conflicts identified.
The study used a high-fat diet supplied by a pharmaceutical firm, but no other industry ties are evident. No conflict of interest declaration was provided.
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 1 claim from it.
- Indication only
Weak evidence — fewer than 20 studies, so treat this as a starting point, not a fact.
Evidence