Replace saturated with unsaturated fat
Swap butter, fatty meat and palm fat for rapeseed, olive or nut oil. Moves ApoB and LDL, can raise triglycerides.
Order of magnitude
Replace most saturated fat in cooking with mono- and polyunsaturated fat.
This is the one dietary lever in this database with randomised hard-outcome evidence: reducing saturated fat over at least two years cut cardiovascular events by 21 per cent.
Effects in detail
Each row is a directed edge from our database, with range, latency, evidence grade and the condition under which it applies at all.
| Marker | Effect | Latency | Mode of action | Outcome | Evidence | Condition | Sources |
|---|---|---|---|---|---|---|---|
| Alanine aminotransferase | helps. Lowers Effect size, not in the marker's unit confidence interval of the estimate, not the range one person can expect Two randomised trials of hypocaloric diets high in unsaturated fatty acids lowered ALT with a standardised mean difference of -1.09 (95 % CI -1.49 to -0.69). Grade C: two trials, and the fat quality is confounded with calorie restriction. | not specified | chronic | unclear | Evidence grade C | applies regardless of the starting value | |
| Apolipoprotein B | helps. Lowers Direction known, size not established Reducing saturated fat cut combined cardiovascular events by 21 % (RR 0.79, 95 % CI 0.66 to 0.93; 11 trials, 53,300 participants; GRADE moderate), with small reductions in total cholesterol and LDL-C. No effect size: the Cochrane abstract describes the lipid changes only as small and gives no pooled numbers, and Mensink 2003 reports the direction of its predictive equations without pooled mean differences (gaps.md G-SF1). Trial proxy: ldl_c. | not specified | chronic | unclear | Evidence grade A | applies regardless of the starting value | |
| HbA1c | helps. Lowers Direction known, size not established A meta-analysis of 102 randomised controlled feeding trials with 4220 adults reports that replacing saturated fat with polyunsaturated fat significantly lowered glucose, HbA1c, C-peptide and HOMA, and quantifies the carbohydrate-to-MUFA and carbohydrate-to-PUFA replacements at 0.09 and 0.11 percentage points of HbA1c per 5 % of energy. No effect size is entered because the abstract gives a number for the carbohydrate replacements and only a significance statement for the saturated-to-unsaturated replacement that this lever actually describes (gaps_batch2.md G-S1). | not specified | chronic | unclear | Evidence grade A | applies regardless of the starting value |
What this measure costs
Counteracting effects of the same measure.
| Marker | Effect | Latency | Mode of action | Outcome | Evidence | Condition | Sources |
|---|---|---|---|---|---|---|---|
| Lipoprotein(a) | costs. Raises Direction known, size not established the consensus statement states about 10 to 15 % without an estimate or an interval behind it in the text retrieved The European Atherosclerosis Society consensus statement lists, among non-genetic influences on Lp(a), that replacing dietary saturated fat with carbohydrate or with unsaturated fat RAISES Lp(a) by about 10 to 15 %. Grade C: a figure quoted in a consensus table without a pooled estimate or an interval behind it in the text retrieved. | not specified | chronic | unclear | Evidence grade C | applies regardless of the starting value |
Moves without implying progress
Informational or no established effect: the marker moves or was checked, and that is not progress.
| Marker | Effect | Latency | Mode of action | Outcome | Evidence | Condition | Sources |
|---|---|---|---|---|---|---|---|
| Diastolic blood pressure | checked, nothing happens. No established effect The Cochrane review of saturated fat reduction reports little or no effect on blood pressure across trials of at least two years. A no-effect row. | not specified | chronic | unclear | Evidence grade A | applies regardless of the starting value | |
| Systolic blood pressure | checked, nothing happens. No established effect The Cochrane review of saturated fat reduction reports little or no effect on blood pressure across trials of at least two years. A no-effect row. | not specified | chronic | unclear | Evidence grade A | applies regardless of the starting value | |
| HDL cholesterol | checked, nothing happens. No established effect Little or no effect on HDL-C in the Cochrane review. A no-effect row: this lever works on LDL-C and events, not on HDL-C. | not specified | chronic | no | Evidence grade A | applies regardless of the starting value | |
| Triglycerides | checked, nothing happens. No established effect Saturated-fat reduction had little or no effect on triglycerides across trials of at least two years. The trade-off is hidden in what replaces the fat. | not specified | chronic | unclear | Evidence grade A | applies regardless of the starting value |
Sources
Full details of every study the rows above rely on.
Reduction in saturated fat intake for cardiovascular disease
Hooper et al. (Cochrane) · Cochrane Database of Systematic Reviews · 2020 · Meta-analysis
Dietary Interventions in Patients With Non-alcoholic Fatty Liver Disease: A Systematic Review and Meta-Analysis
Houttu et al. · Frontiers in Nutrition · 2021 · Meta-analysis
Effects of Saturated Fat, Polyunsaturated Fat, Monounsaturated Fat, and Carbohydrate on Glucose-Insulin Homeostasis: A Systematic Review and Meta-analysis of Randomised Controlled Feeding Trials
Imamura et al. · PLoS Medicine · 2016 · Meta-analysis
Lipoprotein(a) in atherosclerotic cardiovascular disease and aortic stenosis: a European Atherosclerosis Society consensus statement
Kronenberg et al. · European Heart Journal · 2022 · Guideline
Effects of dietary fatty acids and carbohydrates on the ratio of serum total to HDL cholesterol and on serum lipids and apolipoproteins: a meta-analysis of 60 controlled trials
Mensink et al. · American Journal of Clinical Nutrition · 2003 · Meta-analysis