What happens to your body when you eat good vs bad fats?
Substituting dietary saturated for monounsaturated fat impairs insulin sensitivity in healthy men and women: The KANWU study
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
This study looked at what happens when people eat more healthy fats (like olive oil) instead of unhealthy fats (like butter) for 3 months.
No biological mechanisms were identified in this study. This may be an epidemiological, observational, or survey-based study that reports associations rather than proposing causal biological pathways.
Systematic Reviews & Meta-Analyses
Max 100Randomized Controlled Trials
Max 90Cohort Studies
Max 72Case-Control Studies
Max 58Cross-Sectional Studies
Max 44Case Reports & Case Series
Max 30Expert Opinion & Narrative Reviews
Max 558 / 90
Evidence Score
Participants are randomly assigned to treatment or control groups, minimizing bias. Considered the gold standard for testing whether an intervention causes an effect.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
This study looked at what happens when people eat more healthy fats (like olive oil) instead of unhealthy fats (like butter) for 3 months.
No biological mechanisms were identified in this study. This may be an epidemiological, observational, or survey-based study that reports associations rather than proposing causal biological pathways.
Systematic Reviews & Meta-Analyses
Max 100Randomized Controlled Trials
Max 90Cohort Studies
Max 72Case-Control Studies
Max 58Cross-Sectional Studies
Max 44Case Reports & Case Series
Max 30Expert Opinion & Narrative Reviews
Max 558 / 90
Evidence Score
Participants are randomly assigned to treatment or control groups, minimizing bias. Considered the gold standard for testing whether an intervention causes an effect.
Publication
Authors
Vessby B, Uusitupa M, Hermansen K, Riccardi G, Rivellese AA, Tapsell LC, Nälsén C, Berglund L, Louheranta A, Rasmussen BM, Calvert GD, Maffetone A, Pedersen E, Gustafsson IB, Storlien LH, KANWU Study
Related Content
Claims (4)
If you're eating a lot of fat—more than 37% of your daily calories—switching to healthier fats like olive oil might not help your body respond to insulin better. But if your overall fat intake is lower, making that switch could actually help.
Eating a lot of saturated fat might make your body less responsive to insulin and cause fat to build up in your liver. If you also eat a lot of protein, it could push your body to make more sugar, which might raise your blood sugar—especially if you're prone to it.
Swapping out bad fats (like butter and fatty meats) for good fats (like olive oil and avocados) can help your body use insulin better—even if you're not changing how many calories you eat.
Eating certain fats can change your 'bad' cholesterol — saturated fats go up a little, but monounsaturated fats go down, even if you're already healthy.