Unsaturated Fat

What Is Unsaturated Fat?

Unsaturated fats are dietary fats in which the fatty acid chains contain one or more double bonds between carbon atoms. These double bonds reduce the degree of hydrogen saturation, creating kinks in the molecular structure that prevent tight packing — which is why unsaturated fats are typically liquid at room temperature. Unsaturated fats are broadly categorized as monounsaturated (one double bond) or polyunsaturated (two or more double bonds).

Unsaturated fats are primarily found in plant-derived oils, nuts, seeds, and fatty fish, and are widely regarded as the most heart-healthy dietary fats.

Health Benefits

Replacing saturated and trans fats with unsaturated fats is consistently associated with improved cardiovascular outcomes in clinical trials and epidemiological studies:

• Reduce LDL ("bad") cholesterol levels
• Maintain or increase HDL ("good") cholesterol levels
• Reduce triglycerides (especially omega-3 polyunsaturated fats)
• Reduce systemic inflammation markers
• Improve insulin sensitivity

The Mediterranean dietary pattern, which is rich in monounsaturated fats from olive oil and nuts, is associated with significantly reduced risk of cardiovascular events in large randomized controlled trials, including the PREDIMED study.

Food Sources

Unsaturated fats are found predominantly in plant foods and oily fish:

• Olive oil: ~73% monounsaturated fat; a benchmark source of MUFA
• Avocado: ~67% of fat is monounsaturated
• Almonds: predominantly MUFA with some PUFA
• Sunflower oil: high in linoleic acid (omega-6 PUFA)
• Salmon: rich in EPA and DHA (omega-3 PUFA)
• Walnuts: high in ALA (omega-3 PUFA) and linoleic acid (omega-6 PUFA)