According to Gram Research analysis, tomato compounds can slow starch digestion by approximately 10% in laboratory conditions, potentially helping blood sugar rise more gradually. A 2026 study in Food & Function found that tomato paste extract was particularly effective, even at lower doses, suggesting multiple beneficial compounds work together. However, these findings come from test-tube studies, not human trials, so real-world effects in people still need confirmation.
A 2026 study published in Food & Function found that compounds in tomatoes can slow down how quickly your body breaks down starch, which could help keep blood sugar levels more stable. Researchers tested tomato extracts from both raw peels and processed paste mixed with cooked starch in a lab setting. When they added tomato compounds at the same weight as the starch, digestion slowed by 10%. The tomato paste extract worked especially well, suggesting that processed tomatoes might have extra benefits. These findings suggest that eating tomatoes with starchy foods like bread or pasta could help your body process them more gradually.
Key Statistics
A 2026 laboratory study published in Food & Function found that tomato phenolic compounds reduced starch digestion by 10% when added in equal amounts to cooked starch.
Tomato paste extract significantly reduced starch digestion even at half the starch weight (12.5 mg extract with 25 mg starch), suggesting synergistic effects of multiple compounds in processed tomatoes.
Raw tomato peel extracts contain substantial amounts of beneficial phenolic compounds, indicating that typically discarded tomato byproducts could be used to enhance the nutritional value of starchy foods.
The Quick Take
- What they studied: Whether compounds found in tomatoes can slow down how quickly your body digests starch (the carbohydrate in foods like bread, rice, and pasta)
- Who participated: This was a laboratory study, not a human trial. Scientists tested tomato extracts mixed with cooked starch using enzymes that mimic human digestion
- Key finding: Tomato compounds reduced starch digestion by 10% when added in equal amounts. Tomato paste extract was particularly effective, even at lower doses, suggesting multiple compounds working together
- What it means for you: Eating tomatoes with starchy meals might help your blood sugar rise more slowly and steadily. However, this was a lab study, so real-world effects in people need further testing
The Research Details
Scientists extracted phenolic compounds (natural plant chemicals with health benefits) from two sources: raw tomato peels and processed tomato paste. They identified exactly which compounds were present using advanced laboratory techniques. Then they mixed these extracts with cooked starch and added digestive enzymes to simulate what happens in your stomach and small intestine.
They tested two different amounts of tomato extract: one where the extract weight matched the starch weight (25 mg each), and another where the extract was half the starch weight (12.5 mg extract with 25 mg starch). By measuring how much starch the enzymes broke down, they could determine whether tomato compounds interfered with digestion.
This type of study is called an in vitro model, meaning it happens in a test tube or lab dish rather than inside a living person. It’s a useful first step to understand how foods might interact, but results don’t automatically translate to how your body would respond.
Understanding how different foods interact is important because what you eat together affects how your body processes nutrients. If tomato compounds really do slow starch digestion, this could help people manage blood sugar levels, which is especially important for those with diabetes or prediabetes. This research also suggests that tomato byproducts like peels—often discarded—could be valuable for health, reducing food waste while adding nutritional benefits.
This study was published in Food & Function, a peer-reviewed scientific journal, which means experts reviewed the work before publication. The researchers used precise laboratory techniques (LC-MS/MS) to identify exactly which compounds were in the tomato extracts. However, this is a laboratory study, not a human trial, so we don’t yet know if these effects actually happen when people eat tomatoes with starchy foods. The study also didn’t specify sample sizes for the extracts tested, which limits our ability to assess some details.
What the Results Show
When tomato extract was added to starch in equal amounts (25 mg each), starch digestion decreased by 10%. This means the enzymes broke down the starch more slowly, which would theoretically cause blood sugar to rise more gradually in your body.
Interestingly, when researchers used a lower dose of tomato paste extract (12.5 mg with 25 mg starch), the paste extract still significantly slowed digestion. However, the raw tomato peel extract at this lower dose did not have the same effect. This suggests that processed tomato paste contains multiple beneficial compounds that work together synergistically—meaning they’re more powerful when combined than individually.
The researchers believe tomato compounds slow digestion through two possible mechanisms: they may stick to starch molecules and physically block enzymes from breaking them down, or they may directly interfere with the digestive enzymes themselves, or both processes may occur simultaneously.
The study revealed that tomato paste extract was more effective than raw tomato peel extract at lower doses, suggesting that processing tomatoes (like making paste) may concentrate or activate certain beneficial compounds. This finding is practical because it means both fresh and processed tomato products could offer benefits, with processed versions potentially being more potent. The research also highlights that tomato peels—typically discarded—contain significant amounts of these beneficial compounds, suggesting they could be used to enhance other foods.
This research builds on existing knowledge that plant compounds called polyphenols can affect how your body digests carbohydrates. Previous studies have shown similar effects with other foods like beans, berries, and tea. This tomato study is notable because it specifically identifies how tomato compounds interact with starch and demonstrates that both fresh and processed tomato sources contain these beneficial compounds. The 10% reduction in starch digestion is modest but meaningful—similar to effects seen with other plant-based foods studied for blood sugar management.
This study was conducted entirely in a laboratory using test tubes and enzymes, not in human bodies. Real digestion is far more complex, involving multiple enzymes, stomach acid, and individual differences in how people process food. The study didn’t test actual tomato-containing meals, just isolated extracts mixed with starch. We don’t know how much tomato you’d need to eat with a meal to see benefits, or whether the effect would be noticeable in real life. Additionally, the study didn’t measure long-term effects or test whether benefits persist across different types of starchy foods. Human trials are needed to confirm these laboratory findings.
The Bottom Line
Based on this laboratory research, there’s preliminary evidence (moderate confidence) that eating tomatoes with starchy meals might help moderate blood sugar response. However, this should not replace medical advice for people with diabetes. A practical approach would be to include tomatoes in meals with bread, pasta, or rice as part of a balanced diet. Both fresh tomatoes and tomato paste appear beneficial, though paste may be more concentrated. This research suggests tomatoes are worth including in your diet, but shouldn’t be viewed as a substitute for other proven blood sugar management strategies.
This research is most relevant to people interested in managing blood sugar levels, including those with prediabetes or type 2 diabetes, and anyone seeking to optimize their diet for steady energy. People who enjoy tomatoes will appreciate that this research suggests additional health benefits. Food manufacturers might be interested in using tomato byproducts to enhance starchy products. However, people with tomato allergies or sensitivities should not change their diet based on this research.
If these laboratory findings translate to real-world effects, you would likely notice benefits gradually over weeks to months of consistently eating tomatoes with starchy meals. Blood sugar effects would be immediate (within meals), but broader health benefits from improved blood sugar management would develop over longer periods. This is not a quick-fix solution but rather one dietary strategy among many for long-term health.
Frequently Asked Questions
Can eating tomatoes with pasta or bread help control blood sugar?
Laboratory research suggests tomato compounds may slow starch digestion by about 10%, potentially moderating blood sugar response. However, this finding comes from test-tube studies, not human trials, so real-world effects need confirmation through further research.
Is tomato paste better than fresh tomatoes for this effect?
According to the 2026 study, tomato paste extract was more effective at lower doses than raw tomato peel extract, suggesting processing may concentrate beneficial compounds. Both forms appear beneficial, but paste may be more potent.
How much tomato do I need to eat to see blood sugar benefits?
The study doesn’t specify practical serving sizes for people. Laboratory tests used small amounts of concentrated extract. Real-world research is needed to determine how much fresh or processed tomato in actual meals would produce noticeable effects.
Should people with diabetes rely on tomatoes instead of medication?
No. This preliminary laboratory research should not replace medical treatment or medication. Tomatoes may be a helpful dietary addition alongside prescribed diabetes management, but consult your healthcare provider before making changes.
Why does tomato slow down starch digestion?
Researchers believe tomato’s phenolic compounds either physically block digestive enzymes from breaking down starch, or directly interfere with the enzymes themselves, or both. The exact mechanism requires further study in human subjects.
Want to Apply This Research?
- Track meals combining starchy foods with tomatoes and note your energy levels 1-2 hours after eating. Rate your energy stability on a 1-10 scale and monitor whether you experience the typical energy dip that follows high-carb meals
- Add tomato-based components to starchy meals: tomato sauce with pasta, salsa with rice bowls, or tomato soup with bread. Experiment with both fresh tomatoes and tomato paste to see which fits your routine best
- Over 4-6 weeks, maintain a simple log of starchy meals with and without tomatoes, noting hunger levels, energy, and cravings 2-3 hours after eating. This personal tracking helps identify whether tomatoes make a noticeable difference for your individual response
This research is preliminary laboratory evidence and has not been tested in humans. It should not be used to replace medical advice, diagnosis, or treatment from qualified healthcare professionals. People with diabetes or prediabetes should consult their doctor before making dietary changes based on this research. While tomatoes are generally safe and nutritious, individual responses may vary. This article is for educational purposes and does not constitute medical advice.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.