Research

Hormonal

Substituting saturated fatty acids with monounsaturated fatty acids in the diet improves insulin sensitivity, whereas substituting saturated fats with polyunsaturated n-6 fatty acids does not.

To improve insulin sensitivity, focus on replacing saturated fats (like butter) with monounsaturated fats (like olive oil or rapeseed oil). Simply adding more polyunsaturated fats (like corn or sunflower oil) or omega-3 supplements does not appear to improve insulin sensitivity on its own, according to this research.

GoodQualifiesHIGH confidence
In a recent 3-month study, it was shown that insulin sensitivity was impaired when the proportion of saturated fat increased in the diet at the expense of mono-unsaturated fatty acids. Supplementation of n-3 fatty acid to the diet did not affect insulin sensitivity, independent of the fatty acid composition of the background diet.
B. Vessby et al. · Annals of the New York Academy of Sciences · 2002

Why this rating

Based on controlled crossover dietary studies with measured outcomes (clamp technique), though the specific n-6 substitution effect on insulin sensitivity was not significant in the cited study.

Source

Desaturation and Elongation of Fatty Acids and Insulin Action

B. Vessby et al. · Annals of the New York Academy of Sciences · 2002

DOI 10.1111/j.1749-6632.2002.tb04275.x

narrative_reviewCited 317×
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DOI resolved against Crossref · corpus check 2026-06-10

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