Clinical trial · The British journal of nutrition · 2009Abstract only

Safflower seed extract and heart risk markers in men

What it found

In healthy men, taking safflower seed extract for 4 weeks lowered several markers of oxidation and inflammation.

Blood pressure and arterial stiffness did not change significantly overall.

What they found

Studies in people

Oxidized LDL

Circulating oxidized LDL fell significantly after the 4-week safflower seed extract period.

LDL autoantibodies

Autoantibody titres to malondialdehyde-modified LDL dropped significantly after supplementation.

Inflammation marker

The soluble form of vascular cell adhesion molecule-1, sVCAM-1, was significantly reduced after 4 weeks.

Urinary 8-isoprostane

Urinary 8-isoprostane, a marker of oxidative stress, fell significantly with supplementation.

Blood pressure and stiffness

There were no statistically significant differences in blood pressure or brachial-ankle pulse wave velocity, an index of arterial stiffness. However, baPWV was lower than baseline in eleven of twenty subjects and came with a reduction in blood pressure.

Who benefited most

Statistically significant negative correlations were seen between the starting levels of cardiovascular risk markers (autoantibody titres, 8-isoprostane, sVCAM-1 and baPWV) and the effect of the intervention. This suggests people with higher oxidative stress, inflammation or arterial stiffness may get more benefit from safflower seed extract.

What the authors conclude

“This suggested that individuals with elevated oxidative stress, inflammation, and/or arterial stiffness may receive more benefit from SSE supplementation.”
Koyama N, Suzuki K, Furukawa Y, et al, 2009

Also in their conclusions

  • They suggest that individuals with elevated oxidative stress, inflammation, and/or arterial stiffness may receive more benefit from SSE supplementation.

How it was done

Earlier lab and mouse work found that safflower seed extract and its antioxidant compounds reduced LDL oxidation and artery lesions. The authors wanted to see whether the same extract affects oxidative stress, inflammation and aortic stiffness in healthy people.

Twenty Japanese male volunteers took 2.1 g of safflower seed extract daily, providing 290 mg of serotonin derivatives, for 4 weeks. They were measured at baseline, after the 4 weeks, and after a 4-week washout period.

What it can’t tell you

  • We summarised it from the abstract only.
  • This was a small, short trial in healthy Japanese men, so the results may not apply to other groups or to longer use.
  • The study did not compare safflower seed extract against a placebo, so it cannot prove the extract caused the changes seen.

The paper

Title
Effects of safflower seed extract supplementation on oxidation and cardiovascular risk markers in healthy human volunteers
Type
Clinical trial
Evidence
Studies in people
Summarised from
Abstract only
Cite
Koyama N, Suzuki K, Furukawa Y, et al (2009). Effects of safflower seed extract supplementation on oxidation and cardiovascular risk markers in healthy human volunteers. The British journal of nutrition. doi:10.1017/S0007114508025786PubMed 18590590DOI

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