Randomised trial · The Journal of nutrition · 2022

Cottonseed oil and blood cholesterol in adults with high cholesterol

What it found

In adults with high cholesterol, an 8-week diet rich in cottonseed oil lowered total and LDL cholesterol more than a diet rich in olive oil.

The cottonseed oil diet also improved the body's handling of a high-saturated-fat meal.

What they found

Studies in people

Fasting cholesterol

From start to week 8, the cottonseed oil group had greater drops in total cholesterol, LDL cholesterol, non-HDL cholesterol, and apoB compared with the olive oil group. The olive oil group showed no change in these measures.

HDL cholesterol

Both groups had increases in HDL cholesterol and decreases in the total cholesterol to HDL ratio over the 8 weeks, with no difference between groups.

After a high-fat meal

After the 8-week diet, the cottonseed oil group had lower post-meal glucose and triglyceride responses to a high-saturated-fat meal compared with the olive oil group. The olive oil group showed a worsening of these responses.

Weight and compliance

Both groups gained a small amount of weight during the study, about 1 kg, regardless of which oil they ate. Participants reported eating about 91% to 92% of the provided food, and this was similar between groups.

Animal and lab studies

Possible mechanism

The authors suggest that a compound in cottonseed oil called DHSA may block an enzyme involved in fat storage, and that the high polyunsaturated fat content may also help. This mechanism has been shown in animal models but not confirmed in people.

What the authors conclude

“CSO, but not OO, diet enrichment caused substantial improvements in fasting and postprandial blood lipids and postprandial glycemia in hypercholesterolemic adults.”
Prater MC, Scheurell AR, Paton CM, Cooper JA, 2022

Also in their conclusions

  • They conclude that a cottonseed oil-enriched diet improved fasting blood lipids, including total cholesterol, LDL cholesterol, and apoB, and also improved post-meal nonesterified fatty acids and glucose in adults with high cholesterol.
  • They state that the reduction in LDL cholesterol by cottonseed oil (12.2%) could correspond to a 14.6% to 21.4% reduction in coronary artery disease risk.
  • They suggest that cottonseed oil may be a beneficial oil to include in the diet for adults with high cholesterol, but call for more research on other high-polyunsaturated oils, lower doses, different durations, and other populations.

How it was done

The authors wanted to compare how two unsaturated oils, one high in polyunsaturated fat (cottonseed) and one high in monounsaturated fat (olive), affect blood lipids in people with high cholesterol. They noted that the type of unsaturated fat to recommend is still unclear.

They randomly assigned 43 men and women with high cholesterol to eat meals and snacks made with either cottonseed oil or olive oil for 8 weeks. The provided food covered about 60% of daily energy needs, with 30% of energy needs from the assigned oil. Before and after the diet, participants ate a high-saturated-fat meal and had blood tests over 5 hours.

What it can’t tell you

  • This trial cannot show what would happen with lower doses of cottonseed oil or over a longer period, because it used a relatively high dose for 8 weeks.
  • The study did not measure other compounds in the oils, such as phenolic content, so it cannot rule out that these might have contributed to the effects.
  • The trial was single-blinded and relied on self-reported food intake and compliance, which may be less accurate than direct measures.

The paper

Title
Blood Lipid Responses to Diets Enriched with Cottonseed Oil Compared With Olive Oil in Adults with High Cholesterol in a Randomized Trial
Type
Randomised controlled trial
Evidence
Studies in people · animals · lab
Summarised from
Full text
Cite
Prater MC, Scheurell AR, Paton CM, Cooper JA (2022). Blood Lipid Responses to Diets Enriched with Cottonseed Oil Compared With Olive Oil in Adults with High Cholesterol in a Randomized Trial. The Journal of nutrition. doi:10.1093/jn/nxac099Free full textPubMed 35511204DOI

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