Thermogenic nutrients have the potential to augment weight loss by increasing energy expenditure naturally. That is, just by consuming the nutrients, you automatically burn more calories. The extent to which certain nutrients increase caloric burning, and whether the effects dissipate after extended use remains a highly debated topic. Danish researchers publishing in the
International Journal of Obesity
shed some interesting light on the issue. They investigated the thermogenic effects of a formula containing 1500 mg cissus quadrangularis
extract (375 mg catechins and 150 mg caffeine), Tyrosine
(1218 mg), Caffeine
(150 mg), calcium carbonate (3890 mg), and 450 mg cayenne (1.2 mg capsaicin). A group of overweight subjects were required to lose weight for a four week period and then were randomly assigned to take the thermogenic formula or a placebo for 8 weeks. The supplements were taken one hour before breakfast, lunch and dinner. In addition to measures of weight loss and fat loss, the thermogenic effects of the supplements were tested by assessing the energy expenditure for four hours after ingestion. Acute ingestion of the thermogenic supplement caused a significant increase in metabolic rate compared to placebo at baseline. The increase over the 4 hour period after ingestion of the
was on average 22 kcal more than placebo. When the same test was performed after 8 weeks of treatment, the same increase in metabolic rate was observed indicating that there was not a loss in the thermogenic effects of the supplement. In addition, the group taking the thermogenic supplement lost more than 2 pounds of fat compared to the placebo group. This study provides a detailed account of the metabolic and caloric burning properties associated with acute ingestion of a thermogenic formula and further link this response with greater efficacy on fat loss over an extended period of time.
Belza A, Frandsen E, Kondrup J. Body fat loss achieved by stimulation of thermogenesis by a combination of bioactive food ingredients: a placebo-controlled, double-blind 8-week intervention in obese subjects. Int J Obes (Lond). 2007 Jan;31(1):121-30. Epub 2006 Apr 25.