Virgin oil of camelina, safflower, hemp, milk thistle, rapeseed, soya, sunflower, flax, or pumpkin seed, there is a wide variety of seed oils.
To be consumed preferably in the form of organic virgin oil, the seed oils are best for LDL cholesterol.
This is the revelation of a study published in September 2018 in the Journal of Lipid Research.
The researchers used a new technique to draw their conclusions.
SEED OILS AND CHOLESTEROL LDL
Using a statistical technique called network meta-analysis (a statistical tool to combine information from several trials of the same therapeutic area), the researchers combined the results of dozens of studies on dietary oils.
In this way they were able to identify those with the best effect on LDL cholesterol and other blood lipids of patients.
If you want to lower your low-density lipoprotein cholesterol called LDL or "bad cholesterol", the research is clear on one point: you have to swap saturated fat for unsaturated fat.
Many studies establishing that mono and polyunsaturated fats are better for blood lipids than saturated fats, making it difficult to tell which of a plethora of vegetable oils might be the most beneficial.
The sophisticated statistical tools used for this new study help to reduce uncertainty about what the mountain of nutrition literature can tell us.
Using this method, researchers discovered that seed oils were the best choice for people seeking to improve their cholesterol levels.
WHAT SEED OILS ARE BENEFICIARY?
To face the fact that no giant study was done to compare all available oils, the research team developed a networked meta-analysis showing how different oils and solid fats were matched.
The researchers collected 55 studies and evaluated the effects of consuming the same amount of calories from two or more different oils on the participants' blood lipids.
To be included in the analysis, a study had to compare the effect of at least two oils or fats (on a list of 13) on patients' LDL, or other blood lipids like total cholesterol, cholesterol HDL or triglycerides, over at least three weeks.
Suppose butter and sunflower oil have been tested against olive oil. Statistical approaches to the networked meta-analysis allowed the team to infer a quantitative comparison between butter and sunflower oil, even if they had never clashed at the clinic.
"The beauty of this method lies in the fact that you can compare several interventions at the same time and you get a ranking for the best oil for that specific result," the researchers said.
"Bad" cholesterol is dangerous in the long run.
In this study, the final rankings indicated that solid fats such as butter and lard are the worst choice for LDL.
The best alternatives are the seed oils. Sunflower, rapeseed, safflower and flax oils gave the best results.
Some people from Mediterranean countries are probably not as happy with this result as they would prefer to see olive oil at the top. But this is not the case.
There are some important caveats to research. For starters, he only measured blood lipids. This is not a difficult clinical result.
LDL is a causal risk factor for coronary heart disease, but it is not coronary heart disease.
However, the researchers point out that it may be difficult to conduct a study comparing these clinical findings. For starters, someone would need to find study participants eager to eat a single type of fat for years.
Meta-analyzes may be misleading by combining several unreliable data into a seemingly fictitious ranking.
In this case, for example, there was not enough evidence to choose a "winner" with confidence among the seed oils.
In addition, the most effective oils for reducing LDL were not the most beneficial for triglycerides and HDL cholesterol.
However, keeping in mind the appropriate caveats, the research team is optimistic about the potential of networked meta-analysis to help researchers synthesize disparate clinical studies in the future.
Effects of oils and solid fats on blood lipids: a systematic review and network meta-analysis. Journal of Lipid Research, 2018; http://www.jlr.org/content/59/9/1771, 59 (9): 1771 DOI: 10.1194 / jlr.P085522