Compositions (e.g., pharmaceutical compositions, nutraceutical compositions or medical food compositions) comprising tannic acids, particularly tannic acids having more than three galloyl moieties, methods of preparing such, and uses thereof for treating obesity, hyperlipidemia, diabetes, or central nervous system disorders.本發明提供含鞣酸(特別是具有多於三個沒食子醯基團之鞣酸)之組合物(例如:藥學組合物、營養組合物或醫療食品組合物)、製備該組合物之方法、以及其用於治療肥胖、高血脂症、糖尿病或中樞神經系統疾病之用途。