Are fats like butter and margarine bad for you?

Original Title

Intake of saturated and trans unsaturated fatty acids and risk of all cause mortality, cardiovascular disease, and type 2 diabetes: systematic review and meta-analysis of observational studies

Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms

Summary

This study looked at what happens when people eat different kinds of fats over many years. It found that eating more butter or meat fat doesn’t seem to raise your risk of heart disease or diabetes, but eating margarine with artificial trans fats does.

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Surprising Findings

Ruminant trans fats (from dairy/meat) showed no harm — while industrial trans fats were deadly.

Most people think 'trans fat = bad' — but this study proves the source matters. Natural trans fats in cheese don’t act like the ones in donuts.

Practical Takeaways

Avoid processed foods with 'partially hydrogenated oils' — they’re the real danger.

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