Introduction
When examining the efficacy of dietary interventions, clinical trials are considered to be the gold standard of research.
Unfortunately, these studies are more difficult to conduct, and thus there are only a few of them. These studies have found little benefit to reducing saturated fat intake.
Review
A study of 48,835 post-menopausal women found that a diet low in saturated fat decreased LDL by 3.55 mg/dl (which is not a whole lot), but did not decrease incidence of cardiovascular disease (1).
A study of 2,033 men found no reduction in ischaemic heart disease in those who were told to reduce fat intake (2).
A study of 4,393 men and 4,664 women found no reduction in cardiovascular events or deaths for those who cut their saturated fat intake in half (3).
A study of 12,866 men found no significant difference in mortality from CHD or total mortality in those who were instructed to consume less than 10% of their daily calories from saturated fat (4).
A study of 846 subjects found no difference in sudden death or myocardial infarction between those who consumed 40% of their calories from animal fat (5).
Conclusions
The few clinical trials that have been done do not support the theory that decreasing saturated fat intake has any beneficial effects.
References
1 Howard BV, et al. Low-fat dietary pattern and risk of cardiovascular disease: the women’s health initiative randomized controlled dietary modification trial. JAMA. 2006 Feb; 295(6).
2 Burr ML, et al. Effects of changes in fat, fish, and fiber intakes on death and myocardial reinfarction: diet and reinfarction trial (dart). Lancet. 1989 Sep; 334(8666): 757-761.
3 Frantz ID, et al. Test of effect of lipid lowering by diet on cardiovascular risk. The Minnesota coronary survey. Arteriosclerosis, Thrombosis, and Vascular Biology. 1989; 9: 129-135.
4 MRFIT Research Group. Multiple risk factor intervention trial: risk factor changes and mortality results. JAMA. 1982 Sep; 248(12): 1465-1477.
5 Dayton S, et al. A controlled clinical trial of a diet high in unsaturated fat in preventing complications of atherosclerosis. Circulation. 1969; 40: II-1-II-63.