Randomised trial · The British journal of nutrition · 2016Abstract only

Calcium and lycopene absorption from tomatoes in people

What it found

Adding calcium to a tomato meal cut the amount of lycopene getting into the blood of healthy adults by 83%.

The authors also saw changes in lab tests that may explain why.

What they found

Studies in people

Lycopene in blood

Adding calcium to the tomato meal reduced the amount of lycopene that reached the blood by 83%.

Animal and lab studies

Lab digestion test

In the lab digestion model, calcium did not change how much lycopene formed into tiny droplets or how big those droplets were.

Droplet charge

Calcium lowered the electrical charge of the mixed droplets by 39% in the lab tests.

What the authors conclude

“In conclusion, a nutritional dose of Ca can impair dietary LYC bioavailability in healthy humans.”
Borel P, Desmarchelier C, Dumont U, et al, 2016

Also in their conclusions

  • They conclude that a nutritional dose of calcium can impair dietary lycopene absorption in healthy humans.
  • They say this inhibition could be because calcium reduces the electrical charge of micelles.
  • They call for a thorough assessment of the effects of calcium, or other divalent minerals, on the absorption of other carotenoids and fat-soluble micronutrients.

How it was done

Lycopene is taken up by the body poorly and varies a lot between people. Lab tests had suggested calcium might get in the way, but it was not known if this happens in people.

Ten healthy adults ate a test meal with 19 mg of lycopene from tomato paste, either alone or with 500 mg of calcium carbonate. Their blood lycopene levels were measured over 7 hours. A lab digestion model was also used to test rising calcium doses.

What it can’t tell you

  • We summarised it from the abstract only.
  • This was a small study of ten healthy adults, so the results may not apply to everyone.
  • The lab digestion model cannot show what happens inside the human body.

The paper

Title
Dietary calcium impairs tomato lycopene bioavailability in healthy humans
Type
Randomised controlled trial
Evidence
Studies in people · animals · lab
Summarised from
Abstract only
Cite
Borel P, Desmarchelier C, Dumont U, et al (2016). Dietary calcium impairs tomato lycopene bioavailability in healthy humans. The British journal of nutrition. doi:10.1017/S0007114516004335PubMed 28069089DOI

Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error