Safety and efficacy of NT, an herbal supplement, in treating human obesity

Abstract

Objective:

A human pilot study testing the safety and effectiveness of NT (Number Ten), a dietary herbal supplement made from rhubarb, ginger, astragulus, red sage and turmeric, to reduce food intake and cause weight loss.

Research methods and procedures:

A total of 24 healthy women, 18–60 years, body mass index 25–35 kg/m² on no chronic medication were randomized to four groups of six: (1) oral freeze-dried NT 6 gm/day, (2) bed-dried NT 6 gm/day, (3) freeze-dried NT 12 gm/day or (4) placebo. Number Ten dose was escalated over 3 weeks and maintained for 8 weeks on a 700 kcal/day diet below maintenance. Food intake was measured at baseline and 4 weeks. Safety parameters were monitored weekly during dose escalation, week 6 and week 12.

Results:

Weight loss was 1.8 kg for placebo and 0.4 kg for 500 mg NT whereas the 250 mg bed- and freeze-dried NT gained 0.43 and 0.87 kg, respectively (P=NS). The food intake increased 74 kcal with 250 mg freeze-dried NT and decreased 193.7 kcal with 500 mg freeze-dried NT (P<0.01). There was a dose-related incidence of loose stools in the NT groups, but no other toxicity was seen. Number Ten was found to contain sennosides, known laxatives and gallic acid, which is known to give weight loss in rodents.

Discussion:

The human dose equivalent of NT used in this study was &frac16; and &frac112; of that shown to give well-tolerated weight loss in rodents. Number Ten will not be an effective dietary herbal supplement for the treatment of obesity owing to dose-limiting gastrointestinal toxicity.