Role of Different Dietary Saturated Fatty Acids for Cardiometabolic Risk

David Iggman; Ulf Risérus

Clin Lipidology. 2011;6(2):209-223.

Future Perspective

Future studies should emphasize differences between different SFA, food sources, origins and foodstuffs (i.e., which SFA-containing foods are especially detrimental for cardiometabolic and overall health), and further determine whether there are any benefits of certain amounts of select SFA intake on intermediate end points to CVD, as studies on disease end points or mortality may be unattainable. One feasible way to overcome methodological difficulties is by utilizing biomarkers. This is mainly attainable for dairy intake, making such studies especially warranted.

1 2 3 4 5 6 7 8 9 10 11 12

Next Section

Financial & competing interests disclosure
David Iggman is supported by Landstinget Dalarna (County Council of Dalarna), Center for Clinical Research Dalarna, Falun; Svärdsjö District Health Care Center, Falun, Sweden; and Uppsala University, Sweden. Ulf Risérus was supported by a grant from NordForsk (Nordic Centre of Excellence in Food, Nutrition and Health [SYSDIET]), Swedish Council for Working Life and Social Research (FAS), Family Ernfors Fund for Diabetes, Erik, Karin and Gösta Selanders Foundation, Diabetesfonden, and the Swedish Heart–Lung Foundation. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.
No writing assistance was utilized in the production of this manuscript.

Sidebar

Executive Summary

Various metabolic effects of separate saturated fatty acids

Most dietary saturated fatty acids (SFA) are long chain 14:0–18:0.
Short-chain SFA may have a role in prevention of cancer and inflammation of the large intestine, medium-chain SFA may reduce adiposity, 12:0 may have antimicrobial properties, and 14:0 and 16:0 may have various regulatory functions in the cell via protein fatty acid acetylation.

Effects on cardiovascular risk factors

Long-chain SFA increase total cholesterol and LDL-C, except 18:0, which is neutral. Lauric acid (12:0) is the most potent SFA for raising cholesterol, but also reduces the total cholesterol:HDL-C ratio.
Some studies suggest an atherogenic and prothrombotic effect of 18:0, but not consistently. Whether 18:0 is preferable to 16:0 as a substitute for trans -fatty acids is not clear, but according to effects on blood lipids solely, this may be true.

Effects on cardiovascular disease

Overall, SFA consumption has not been clearly demonstrated to increase cardiovascular disease (CVD) in epidemiological studies using self-reported questionnaires, but the data may be weakened by reporting bias and residual confounding.
Exchanging SFA with polyunsaturated fatty acids decreases CVD risk and mortality.
Studies on individual SFA are limited but one large cohort study indicates an increased risk of coronary heart disease for 12:0, 14:0, 16:0 and 18:0, and biomarker studies suggest detrimental effects from circulating and tissue 16:0 content.

Effects on insulin resistance & diabetes

Long-chain SFA 16:0 and 14:0 seem detrimental to β-cell function in vitro and in animal experiments.
Biomarker studies have demonstrated associations between circulating 14:0, 16:0, and 18:0 and diabetes incidence, although this may only partly reflect dietary SFA intake.
Circulating 15:0 is inversely associated with diabetes incidence and may reflect dairy food intake, but also a 'healthy lifestyle', or other factors not captured due to residual confounding.

Dairy intake & cardiometabolic risk

High-fat dairy products raise LDL-C, and although controlled studies where dairy fat has been a major SFA source indicate increased CVD risk compared with polyunsaturated fatty acids, little epidemiological evidence exists for detrimental effects of dairy intake on disease end points, despite its SFA and trans -fatty acid content.
Milk fat biomarkers 15:0 and 17:0 have been inversely associated with insulin resistance and risk for myocardial infarction, but whether such relationships are explained by SFA-specific effects of dairy foods is unknown.
Long-term controlled intervention studies using high-fat dairy foods versus other types of fats are needed to confirm the epidemiological associations.
It will, however, be challenging to separate any potential health effect of dairy fat between the different individual SFA, as well as from other micronutrients and protein found in dairy products.