Meta-analysis · Scientific reports · 2016Conflicts declared

Beta-carotene in diet and blood linked to death risk

What it found

In 13 studies of people, those with higher beta-carotene in their diet or blood were less likely to die during the follow-up period.

The studies followed people over time, so they can show a link but not cause and effect.

What they found

Studies in people

Dietary beta-carotene

People with the highest dietary beta-carotene intake had a lower risk of death from any cause than those with the lowest intake. The result was consistent across subgroup and sensitivity analyses.

Blood beta-carotene

People with the highest levels of beta-carotene in their blood had a lower risk of death from any cause than those with the lowest levels. This finding was also stable in sensitivity analyses.

Studies in people and animals

Supplements versus food

The authors note that trials of beta-carotene supplements have shown no benefit or discouraging results, unlike the observational studies of dietary or blood beta-carotene. They suggest this may be because supplements use higher doses or lack other nutrients found in natural foods.

Other findings

Possible explanations

The authors discuss that beta-carotene may act through its conversion to vitamin A, its antioxidant effects, or by boosting immune cell function. They also mention that the link could be due to other healthy habits or nutrients in people who eat more beta-carotene-rich foods.

What the authors conclude

“In conclusion, dietary or circulating beta-carotene was inversely associated with risk of all-cause mortality.”
Zhao LG, Zhang QL, Zheng JL, et al, 2016

Also in their conclusions

  • They conclude that dietary or circulating beta-carotene was inversely associated with risk of all-cause mortality.
  • They advise that more studies should be conducted to clarify the dose-response relationship between beta-carotene and all-cause mortality.

How it was done

The authors note that studies on beta-carotene and death risk had given inconsistent results, and they wanted to clarify the link in the general healthy population.

They pooled 13 studies that followed 174,067 people for 2 to 25.7 years, during which 17,657 deaths occurred. Seven studies looked at dietary beta-carotene and seven at blood levels, with one study reporting both.

What it can’t tell you

  • These were observational studies that followed people over time. They can show a link between beta-carotene and death risk, but they cannot prove that beta-carotene causes the lower risk.
  • The authors note that unmeasured lifestyle or dietary factors could have influenced the results.

The paper

Title
Dietary, circulating beta-carotene and risk of all-cause mortality: a meta-analysis from prospective studies
Type
Meta-analysis
Evidence
Studies in people · animals · lab
Summarised from
Full text
Cite
Zhao LG, Zhang QL, Zheng JL, et al (2016). Dietary, circulating beta-carotene and risk of all-cause mortality: a meta-analysis from prospective studies. Scientific reports. doi:10.1038/srep26983Free full textPubMed 27243945DOI

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