Obesity[1] is a global health concern that can be largely mitigated by healthy lifestyle choices[2]. For people who already have obesity, behavioral interventions based on changes to diet and exercise habits are a first-line treatment option. However, adherence can vary among people depending on a host of factors, with many people wishing they could just take a pill[3] instead. Why not both?
Spirulina[4] is a blue-green algae (cyanobacteria) that has emerged as a trendy ‘superfood’ supplement due to its high phytochemical (phenolic compounds, carotenoids, and tocopherols) and essential nutrient content (proteins, n-3 and n-6 fatty acids). Recent studies, mostly done in animals, have demonstrated the antioxidant[5], anti-inflammatory[6], and blood-lipid lowering[7] activity of spirulina, attributable to its phytochemicals. Lower body fat, mass, and blood lipid concentrations were demonstrated[8] in mice administered a high fat diet and spirulina when compared to mice only fed a high fat diet.
A couple of human trials have evaluated the influence of spirulina, finding slight improvements in body composition and blood lipids. One study[9] had obese participants supplement with one gram of spirulina per day for 12 weeks and reported slightly reduced bodyweight, total cholesterol, and appetite more than placebo. Another study[10] supplemented obese individuals with two grams of spirulina per day, also for 12 weeks, and also demonstrated slight reductions in bodyweight and triglycerides, when compared to placebo.
Spirulina studies suggest several benefits that could apply to overweight and obese people. However, few controlled studies have evaluated the effect of spirulina supplementation, let alone spirulina intake in combination with exercise, on markers of obesity and cardiovascular disease risk in humans. The authors of the study under review designed a double-blind, randomized, crossover controlled trial to assess changes in body composition and cardiorespiratory fitness.
Obesity and excess weight are major risk factors for cardiovascular disease and are preventable with behavioral intervention. Spirulina is a nutraceutical that has demonstrated antioxidant, anti-inflammatory, and hypolipidemic activity in animal studies. The authors of the study under review designed a double-blind, randomized, crossover controlled trial to evaluate the effect of spirulina supplementation with and without concomitant exercise on body composition and cardiorespiratory fitness since no controlled human studies currently exist.