The Healthspan Map · Nutrient

Trans fat

Linked to getting too much

Where an excess of Trans fat is linked — 6 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
Trans fat	Don't overdo	Strong	Review / narrative	Trans fats raise LDL and lower HDL - the worst dietary fat for the lipid profile.	Lifestyle & lipids (Endotext) (opens in a new tab)
Trans fat	Don't overdo	Strong	RCT / meta-analysis	Trans fats raise LDL and lower HDL - the worst dietary fat for the lipid profile.	Effects of dietary fatty acids and carbohydrates on the ratio of serum total to HDL cholesterol: a meta-analysis of 60 controlled trials, Am J Clin Nutr 2003 (opens in a new tab)
Trans fat	Don't overdo	Moderate	Cohort / observational	Increasing trans-fat intake by even 2% of energy significantly raised ovulatory-disorder infertility risk, and trans/saturated fats relate to poorer sperm quality.	Female fertility nutrition review (PMC8634384) (opens in a new tab)
Trans fat	Don't overdo	Moderate	Cohort / observational	Partially hydrogenated (trans) fats, concentrated in ultra-processed foods, are linked to higher type 2 diabetes risk.	Ultra-processed food & T2D cohorts (opens in a new tab)
Trans fat	Don't overdo	Moderate	Review / narrative	Industrial trans fats raise CRP/IL-6 and endothelial inflammation.	Trans fat & CRP (opens in a new tab)
Trans fat	Don't overdo	Strong	RCT / meta-analysis	Industrial (artificial) trans fat has no safe level and clearly raises CVD; WHO and FDA have moved to eliminate it. Small amounts occur naturally in ruminant dairy/meat.	Effects of dietary fatty acids and carbohydrates on the ratio of serum total to HDL cholesterol: a meta-analysis of 60 controlled trials, Am J Clin Nutr 2003 (opens in a new tab)