The invention teaches that supplementation with (-)-hydroxycitrate constitutes a novel means of modulating the angiotensin-converting enzyme (ACE)/renin-angiotensin-aldosterone system and is useful for preventing, treating and ameliorating conditions involving the angiotensin-converting enzyme (ACE)/renin-angiotensin-aldosterone system. The discovery that HCA has angiotensin-converting enzyme (ACE)/renin-angiotensin-aldosterone system-moderating effects allows for the creation of novel and more efficacious approaches to preventing and ameliorating conditions that arise from excessive ACE activity. These include cardiovascular diseases in general, heart failure, ventricular remodeling, ejection fraction issues, atrial fibrillation, and a wide variety of renal conditions. Other health conditions discovered to be influenced by the angiotensin-converting enzyme (ACE)/renin-angiotensin-aldosterone system would similarly be expected to be influenced. It is yet a further advantage of the present invention to provide a means--one that is accompanied by few or no side effects--of maintaining such improved status without resort to special diets. Furthermore, this discovery makes possible the development of adjuvant modalities that can be used to improve the results realized with other treatment compounds while at the same time reducing the side effects normally found with such drugs. HCA delivered in the form of its potassium salt is efficacious at a daily dosage (bid or tid) of between 750 mg and 10 grams, preferably at a dosage of between 3 and 6 grams for most individuals. A daily dosage above 10 grams might prove desirable under some circumstances, such as with extremely large or resistant individuals, but this level of intake is not deemed necessary under normal conditions.