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 4-caffeoylquinic acid (4-CQA) to total chlorogenic acids (tCGA) (5-CQA/tCGA) of from about 0.1 to about 0.2. More preferably, the green coffee extract comprises from about 6% to about 8% of 4-caffeoylquinic acid and has a total chlorogenic acid concentration that exceeds about 45%. A preferred method of administration consists of administering the green coffee extracts is a dosage of about 200 mg twice a day prior to meals on an empty stomach.