If you want to lower your low-density lipoprotein cholesterol, called LDL or, colloquially, “bad cholesterol,” the research is clear about one thing:
You should exchange saturated fats with unsaturated fat.
If you want to know what you should use to sauté your dinner, that’s a harder question to answer.
Many of the studies establishing that mono- and polyunsaturated fats are better for blood lipids than saturated fats swapped out one food source at a time, making it hard to tell which of a plethora of vegetable oils might be most beneficial.
In a paper published in the Journal of Lipid Research this month, researchers extracted insight from published studies on the effect of various dietary oils on blood lipids.
They found that seed oils were the best choice for people looking to improve their cholesterol.
The researchers rounded up 55 studies dating to the 1980s that assessed the effects of consuming the same amount of calories from two or more different oils on participants’ blood lipids.
Suppose both butter and sunflower oil had been tested against olive oil.
The statistical approaches allowed the team to infer a quantitative comparison between butter and sunflower oil, even if they had never faced off in the clinic.
In this study, the final ranking indicated that, as your doctor has been telling you for years, solid fats like butter and lard are the worst choice for LDL.
The best alternatives are oils from seeds.
“Sunflower oil, rapeseed oil, safflower oil and flaxseed oil performed best,” said the lead author.
“Some people from Mediterranean countries probably are not so happy with this result, because they would prefer to see olive oil at the top. But this is not the case.”
There are a few important caveats to the research. For starters, it measured only blood lipids. “This is not a hard clinical outcome,” said the author.
Meta-analyses run the risk of misleading by combining several pieces of low-confidence data into a falsely confident-sounding ranking.
In this case, for example, there was not enough evidence to choose a “winner” confidently among the seed oils.
What’s more, the oils best at lowering LDL were not the most beneficial for triglycerides and HDL cholesterol.
However, with the appropriate caveats in mind, the team is optimistic about the potential for their analysis to help researchers synthesize disparate clinical studies in the future.
Source: American Society for Biochemistry and Molecular Biology.