A study published in the British Journal of Nutrition determined that a calcium-enriched diet may impair the ability of tomato lycopene to be absorbed by healthy humans.
Lycopene (LYC) has been defined as a carotenoid (a group of red and yellow pigments) pigment (a natural substance that colors animal and plant tissues) that is responsible for the red color of tomatoes and tomato products. Previous research has established a negative association between the proportion of LYC in the bloodstream and the ingestion of LYC with cardiovascular disease risk and prostate cancer.
Some in vitro (within a test tube or other laboratory container) research has demonstrated that the bioaccessibility (the ability of a substance to interact with and be absorbed by a living being) of LYC was hindered by calcium. Therefore, other researchers have hypothesized that if a similar interaction occurs in humans, then the presence of calcium might limit LYC absorption.
The two principal aims of a new study were to examine whether incorporating calcium into one’s diet could reduce the LYC bioavailability in humans and to uncover what biological processes are involved in this interaction.
10 healthy individuals (5 females and 5 males) were recruited for this study. Subjects were given two LYC-rich test meals separated by three weeks; the meals contained a supplement of 500 mg of calcium or had no supplement. Two hours after subjects consumed the control meal (with no calcium supplementation), researchers noted that the LYC plasma (the clear liquid part of the blood) concentration significantly increased.
Importantly, LYC plasma levels were not elevated in subjects until 5 hours following the consumption of the calcium-enriched meal.
These results indicate that a 500 mg supplementation of calcium to food containing LYC (in this case tomato paste) diminished the bioavailability of LYC in the blood. This is the first time an effect such as this has been documented by researchers.
Written By: Melissa Booker