The consumption of non-sugar sweeteners (NSS) has increased during pregnancy. The European Food Safety Agency suggested that steviol glycosides, such as Rebaudioside A (RebA), the major sweetener component of stevia, are safe for humans up to a dose of 4 mg/kg body weight/day. However, the World Health Organization recommended in 2023 the restraint of using NSS, including stevia, at any life stage, highlighting the need to study NSS safety in early periods of development. We aimed to study the mitochondrial and cardiometabolic effects of long-term RebA consumption during the reproductive stage of the life cycle. Female rats were exposed to RebA (4 mg steviol equivalents/kg body weight/day) in the drinking water from 4 weeks before mating until weaning. Morphometry, food and water consumption, glucose and lipid homeostasis, heart structure, function, and mitochondrial function were assessed. RebA showed an atrophic effect in the heart, decreasing cardiomyocyte cross-sectional area and myocardial fibrosis without repercussions on cardiac function. Mitochondrial and myofilamentary functions were not altered. Glucose tolerance and insulin sensitivity were not affected, but fasting glycemia and total plasma cholesterol decreased. This work suggests that this RebA dose is safe for female consumption during the reproductive stage, from a cardiometabolic perspective. However, studies on the effects of RebA exposure on the offspring are mandatory.
Keywords: cardiometabolism; lactation; pregnancy; rebaudioside A.