Effect of Citrus Aurantium Combined with Caffeine and/or Tea Catechins on Body Fat Accumulation and Its Safety in Rats

We investigated the weight loss efficacy and safety of Citrus aurantium (CA, 1,000 mg/kg diet) along with usual levels of adrenergic stimulants in foods, i.e. caffeine (100 mg/kg diet) and/or tea catechins (500 mg/kg diet), in rats for 44 or 45 days. Even in combination with caffeine and tea catechins, the suppressive effect of CA against body fat accumulation was negligible, whereas no deleterious influences concerning cardiotoxicity were observed. Thus, although the efficacy of CA for weight loss seems to be questionable, no safety problems may occur even in people who habitually consume coffee and tea. However, it is noteworthy that the intake of CA markedly elevated the urinary excretion of adrenaline, and this was not affected by intake of caffeine and/or tea catechins at the usual levels. Therefore, the safety of CA intake with high levels of caffeine and tea catechins, especially in people at risk of heart disease, remains to be elucidated further.