The Healthspan Map · Nutrient

Polyunsaturated fat

Linked to getting too little

Where a shortfall of Polyunsaturated fat is linked — 3 sources.In the order the Map holds them: strongest evidence first. That is a statement about the evidence, not about what matters most.
Nutrient or lever	Direction	Strength	Evidence type	What was found	Source
Polyunsaturated fat	Eat enough of	Moderate	Cohort / observational	Low omega-3 PUFA status is linked to depression and impaired cognition; PUFAs are central to brain structure and anti-inflammatory signaling.	Omega-3 / mood literature (opens in a new tab)
Polyunsaturated fat	Eat enough of	Moderate	RCT / meta-analysis	Low omega-3 PUFA status is linked to depression and impaired cognition; PUFAs are central to brain structure and anti-inflammatory signaling.	"Omega-3 polyunsaturated fatty acids in treating depression: a meta-analysis", J Affect Disord 2025 (opens in a new tab)
Polyunsaturated fat	Eat enough of	Moderate	Review / narrative	Replacing saturated fat with polyunsaturated fat lowers LDL cholesterol - one of the most reliable dietary changes for lipids.	Lifestyle & lipids (Endotext) (opens in a new tab)