An analysis of 121 studies involving nearly 2.7 million people found that higher tomato and lycopene intake was associated with modest reductions in overall cancer risk and stronger declines in cancer-related death.
By yourNEWS Media Newsroom
Tomatoes may offer measurable protection against cancer and cancer-related death, with a large scientific review finding that people who consumed more lycopene or had higher levels of the nutrient in their blood generally experienced better outcomes than those with lower exposure.
The systematic review and dose-response meta-analysis, published in Frontiers in Nutrition, examined 121 prospective studies drawn from four scientific databases and included nearly 2.7 million participants. Researchers evaluated both tomato consumption and lycopene intake, along with blood levels of lycopene, to determine how each measure related to cancer incidence and mortality.
Lycopene is the natural pigment responsible for the red color of tomatoes. It is also a fat-soluble antioxidant, meaning the body absorbs it more efficiently when tomatoes are cooked and eaten with foods containing healthy fats.
Across the studies, participants with the highest dietary lycopene intake had a 5% lower overall risk of developing cancer than those with the lowest intake. The association was stronger when researchers measured lycopene directly in the blood, with the highest levels linked to an 11% lower cancer risk.
That difference suggests that absorption may be as important as the amount consumed. Two people could eat similar quantities of tomatoes but absorb different amounts of lycopene depending on how the food is prepared, what it is eaten with and individual differences in digestion and metabolism.
The mortality findings were more pronounced. Higher tomato consumption was associated with an 11% lower risk of dying from cancer, while higher lycopene intake was linked to a 16% reduction. Participants with the highest blood lycopene levels had a 24% lower risk of cancer death than those with the lowest levels.
Lung cancer showed the strongest mortality association identified in the review. High blood lycopene levels corresponded with a 35% lower risk of death from the disease.
The findings involving prostate cancer were less consistent. One part of the analysis showed that risk declined as lycopene intake increased, but overall dietary lycopene consumption did not produce a statistically significant reduction in prostate cancer risk. Researchers said the evidence for that particular cancer remains uncertain and requires further study.
The review also identified a range in which the apparent benefits were greatest. Daily lycopene intake of approximately 5 to 8 milligrams was associated with the strongest reduction in cancer risk, an amount roughly equivalent to one or two medium tomatoes. Consuming more than 10 milligrams per day did not appear to provide additional protection.
Preparation can substantially affect how much lycopene enters the bloodstream. Processed tomato products, including tomato sauce, soup and juice, often contain more concentrated lycopene than fresh tomatoes. Heating also breaks down plant tissue, making the nutrient easier for the body to absorb.
Pairing cooked tomatoes with olive oil, avocado or another source of healthy fat can further increase absorption because lycopene dissolves in fat rather than water.
Katrina Sommer, an advanced clinical dietitian with OSF HealthCare, said consumers should consider both preparation and food combinations when trying to obtain the nutrient.
“These need to be absorbed very well in our system,” Sommer said. “To do that, cook them and you can drizzle olive oil on them so we can absorb those nutrients optimally.”
Sommer said tomato sauce and tomato soup can also contribute meaningful amounts of lycopene, making fresh tomatoes only one of several practical options.
Although the review was large, the authors cautioned that its findings do not prove tomatoes or lycopene directly prevent cancer. The studies were observational, meaning researchers identified patterns among people’s diets and health outcomes without assigning participants to eat specific foods under controlled conditions.
People who regularly consume tomatoes may also be more likely to follow other healthy habits, including eating more vegetables, exercising, smoking less or consuming less processed food. Those behaviors could contribute to some of the differences in cancer risk and mortality.
Most of the underlying studies were conducted in the United States and Europe. The researchers therefore cautioned against assuming the same results would apply equally across all populations because dietary patterns, genetics, environmental exposures and lifestyle habits vary considerably by region.
Even with those limitations, the association appeared repeatedly across the 121 studies, some of which followed participants for nearly 30 years. The consistency of the findings strengthened the case for further research into lycopene and its possible role in cancer prevention and survival.
Sommer recommended obtaining lycopene through food rather than relying on supplements. She also advised following a predominantly plant-based diet while limiting red meat, processed meat, alcohol and added sugar.
Tomatoes alone should not be viewed as a treatment or guaranteed safeguard against cancer, but the review suggests they can be a useful part of a broader dietary pattern centered on vegetables, fruits and other minimally processed foods.
For most people, adding one or two tomatoes a day, or regularly including cooked tomato sauce or soup with a healthy fat, may provide enough lycopene to reach the range associated with the strongest benefits identified in the analysis.
Source: Natural News
Original article
Comments