A method of controlling body weight in humans by administering an amount of decaffeinated green coffee extract effective to treat a subject. A preferred green coffee extract contains a ratio of 5-caffeoylquinic acid (5-CQA) and total chlorogenic acids (tCGA) (5-CQA/tCGA) of between about 0.2 and 0.3. More preferably, the concentration of tCGA is greater than about 45% and the concentration of 5-CQA is less than about 10%. A preferred method of administration consists of administering between about 200 mg and about 1,000 mg per day, more preferably administering about 400 mg per day.