Safety of Supplementation of Omega-3 Polyunsaturated Fatty Acids: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
Jane Pei‐Chen Chang, Ping‐Tao Tseng, Bing‐Syuan Zeng, Cheng‐Ho Chang, Huanxing Su, Po‐Han Chou, Kuan‐Pin Su
Abstract
There is no comprehensive review of the evidence to support omega-3 polyunsaturated fatty acids (PUFAs) as a relatively safe and tolerable intervention. This study aimed to provide a meta-analytic and comprehensive review on the adverse effects of all kinds of ω-3 PUFA supplementation reported in randomized controlled trials (RCTs) in human subjects. A systematic review of RCTs published between 1987 and 2023 was carried out based on searches of 8 electronic databases. All RCTs that compared the adverse effects of ω-3 PUFAs containing eicosapentaenoic acid, docosahexaenoic acid, or both compared with controls (a placebo or a standard treatment) were included. The primary outcome was the adverse effects related to ω-3 PUFA prescription. A total of 90 RCTs showed that the ω-3 PUFA group, when compared with the placebo, had significantly higher odds of occurrence of diarrhea (odds ratio [OR] = 1.257, P = 0.010), dysgeusia (OR = 3.478, P < 0.001), and bleeding tendency (OR = 1.260, P = 0.025) but lower rates of back pain (OR = 0.727, P < 0.001). The subgroup analysis showed that the prescription ω-3 PUFA products (RxOME3FAs) had higher ω-3 PUFA dosages than generic ω-3 PUFAs (OME3FAs) (3056.38 ± 1113.28 mg/d compared with 2315.92 ± 1725.61 mg/d), and studies on RxOME3FAs performed more standard assessments than OME3FAs on adverse effects (63% compared with 36%). There was no report of definite ω-3 PUFA-related serious adverse events. The subjects taking ω-3 PUFAs were at higher odds of experiencing adverse effects; hence, comprehensive assessments of the adverse effects may help to detect minor/subtle adverse effects associated with ω-3 PUFAs. This study was registered at PROSPERO as CRD42023401169.