The effect of flaxseed supplementation on body weight and body composition: a systematic review and meta‐analysis of 45 randomized placebo‐controlled trials

Abstract

Summary Flaxseed consumption may be inversely associated with obesity; however, findings of available randomized controlled trials (RCTs) are conflicting. The present study aimed to systematically review and analyse RCTs assessing the effects of flaxseed consumption on body weight and body composition. PubMed, Medline via Ovid, SCOPUS, EMBASE and ISI Web of Sciences databases were searched up to November 2016. Mean changes in body composition indices including body weight, body mass index (BMI) and waist circumference were extracted. Effect sizes were expressed as weighted mean difference (WMD) and 95% confidence intervals (CI). Heterogeneity between studies was assessed with the I2 test. Publication bias and subgroup analyses were also performed. The quality of articles was assessed via the Jadad scale. A total of 45 RCTs were included. Meta‐analyses suggested a significant reduction in body weight (WMD: −0.99 kg, 95% CI: −1.67, −0.31, p = 0.004), BMI (WMD: −0.30 kg m−2, 95% CI: −0.53, −0.08, p = 0.008) and waist circumference (WMD: −0.80 cm, 95% CI: −1.40, −0.20, p = 0.008) following flaxseed supplementation. Subgroup analyses showed that using whole flaxseed in doses ≥30 g d−1, longer‐term interventions (≥12 weeks) and studies including participants with higher BMI (≥ 27 kg m−2) had positive effects on body composition. Whole flaxseed is a good choice for weight management particularly for weight reduction in overweight and obese participants.

Flaxseed oil in the context of a weight loss programme ameliorates fatty liver grade in patients with non-alcoholic fatty liver disease: a randomised double-blind controlled trial

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Does pomegranate consumption affect weight and body composition? A systematic review and meta‐analysis of randomized controlled clinical trials

“…Previous studies have supported the beneficial effects of nutraceuticals and functional foods such as green tea, cranberry, and flaxseed in the management of obesity and subsequent associated complications (Baboota et al, 2013;Hirai et al, 2010;Kovacs & Mela, 2006;Kowalska & Olejnik, 2016;Mohammadi-Sartang et al, 2017;Phung et al, 2010). Pomegranate (Punica granatum) is known as another functional food with beneficial health effects including hypotensive, hypocholesterolaemic, and antiatherosclerotic effects (Viuda-Martos, Fernández-López, & Pérez-Álvarez, 2010).…”

The clinical effects of purslane (Portulaca oleracea) seeds on metabolic profiles in patients with nonalcoholic fatty liver disease: A randomized controlled clinical trial

“…An alternative approach to control the NAFLD parameter is dietary adjuncts such as medicinal plants that encompass various pharmacological properties and probably fewer adverse effects compared with chemical drugs (Benzie & Wachtel-Galor, 2011). Previous investigations have demonstrated the therapeutic effects of functional foods and medicinal plants such as green tea, cranberry, and flaxseed in the management of NAFLD and its subsequent complications (Accattato et al, 2017;Hirai et al, 2010;Kovacs & Mela, 2006;Kowalska & Olejnik, 2016;Mohammadi-Sartang et al, 2017;Phung et al, 2010).…”