Replacing lard with olive oil changed cholesterol in 18 people
What it found
Swapping saturated fat from lard for monounsaturated fat from olive oil lowered LDL cholesterol and improved blood fat profiles.
This was measured in 18 adults with insulin resistance.
What they found
Studies in people
LDL cholesterol dropped
When people switched from the lard diet to the olive oil diet, their LDL cholesterol fell by 7.0%. Their non-HDL cholesterol also went down by 2.5%.
Faster LDL breakdown
The body cleared a specific LDL protein called apoB-100 slightly faster on the olive oil diet, rising by 1.6%. The total amount of this protein in the blood fell by 6.0%.
Very low-density lipoprotein pool
The overall amount of very low-density lipoprotein apoB-100 in the blood dropped by 22.5% when people ate the olive oil diet instead of the lard diet.
Triglyceride-rich particles unchanged
The rate at which the body made or cleared triglyceride-rich particles carrying apoB-48 stayed about the same on both diets.
Other blood fats shifted
The olive oil diet led to lower levels of sphingolipids and higher levels of glycerophospholipids in the blood compared to the lard diet.
What the authors conclude
- They found that replacing saturated fats from lard with monounsaturated fats from olive oil lowers LDL cholesterol in people with insulin resistance.
- They say this happens because the body breaks down LDL particles faster.
- The authors note that the swap also leads to an overall better profile of fats in the blood.
How it was done
Health guidelines suggest swapping saturated fats for monounsaturated fats to help prevent heart disease. Scientists wanted to see how this swap affects blood fats in people whose bodies struggle to use insulin properly.
Eighteen men and women with insulin resistance ate two different diets for four weeks each, with a four week break between them. One diet got most of its fat from lard, and the other from olive oil. All meals were provided by the researchers, and neither the participants nor the staff knew which diet was which at the time.
What it can’t tell you
- We summarised it from the abstract only.
- This trial only included 18 people who already had trouble using insulin properly. It cannot show what would happen in the general population.
- The study lasted four weeks per diet, so it cannot show whether these changes last over many years or prevent heart disease.
Who paid
- Authors work at
- Université Laval, Canada; CHU de Québec-Université Laval Research Center, Canada
The paper
- Title
- Substitution of dietary monounsaturated fatty acids from olive oil for saturated fatty acids from lard increases low-density lipoprotein apolipoprotein B-100 fractional catabolic rate in subjects with dyslipidemia associated with insulin resistance: a randomized controlled trial
- Type
- Randomised controlled trial
- Evidence
- Studies in people
- Summarised from
- Abstract only
- Cite
- Desjardins LC, Brière F, Tremblay AJ, et al (2024). Substitution of dietary monounsaturated fatty acids from olive oil for saturated fatty acids from lard increases low-density lipoprotein apolipoprotein B-100 fractional catabolic rate in subjects with dyslipidemia associated with insulin resistance: a randomized controlled trial. The American journal of clinical nutrition. doi:10.1016/j.ajcnut.2024.03.015Free full textPubMed 38518848DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error