Johanna M. Geleijnse, PhD; Ingeborg A. Brouwer, PhD, MSc; Daan Kromhout, PhD, MSc
Disclosures: Authors have disclosed no conflicts of interest. Forms can be viewed at www.acponline.org/authors/icmje/ConflictOfInterestForms.do?msNum=L14-0321.
Geleijnse JM, Brouwer IA, Kromhout D. Association of Dietary, Circulating, and Supplement Fatty Acids With Coronary Risk. Ann Intern Med. 2014;161:457-458. doi: 10.7326/L14-5018-9
Download citation file:
Published: Ann Intern Med. 2014;161(6):457-458.
TO THE EDITOR:
Chowdhury and colleagues (1) reported no association between SFA and coronary risk, thereby casting doubt on cardiovascular guidelines that advocate increased intake of PUFA at the former's expense. The review examined SFA, MUFA, and PUFA as separate entities. This method, however, is flawed because the health effect of a macronutrient that delivers a substantial amount of daily calories, such as SFA, cannot be studied in isolation but depends on whether other macronutrients are replaced.
Saturated fats are beneficial when they replace trans fatty acids (2). We also know that replacing them with carbohydrates (i.e., a low-fat diet vs. a diet high in SFA) does not confer heart health benefit because both LDL and HDL cholesterol will be reduced, with no change in the LDL:HDL ratio. When MUFAs are consumed instead of SFAs, there is a probable benefit. For PUFAs, the case is convincing based on prospective epidemiologic studies and RCTs(2). Replacing 5% of daily energy intake of SFA with PUFA would lower CHD risk by 13% on the basis of cohort studies and will reduce the risk by 10% on the basis of RCTs (3). Furthermore, it is a misconception that substantial replacement of SFA (such as 5% of total energy intake) could be achieved with ω-3 PUFA. In Western diets, α-linolenic acid combined with fish fatty acids can provide at most 2% to 3% of total energy intake. In these diets, most sources of ω-3 are also high in ω-6. Chowdhury and colleagues cite a meta-analysis(4) that showed a significantly reduced risk for CHD when replacing SFA with PUFA based on “mixed ω-3 plus ω-6 trials.” It should be emphasized, however, that in these trials the level of ω-6 was much higher than that of ω-3 PUFA.
Learn more about subscription options.
Register Now for a free account.
Copyright © 2016 American College of Physicians. All Rights Reserved.
Print ISSN: 0003-4819 | Online ISSN: 1539-3704
Conditions of Use
This PDF is available to Subscribers Only