Lycium barbarum increases caloric expenditure and decreases waist circumference in healthy overweight men and women: pilot study.

BACKGROUND

Lycium barbarum (L. barbarum), a traditional Asian medicinal therapy for diabetes and other conditions, has been shown to increase metabolic rate and to reduce body-weight gains in rodent models, as well as to produce clinical improvements in general feelings of well-being including energy level.

OBJECTIVE

To investigate the impact of L. barbarum consumption on (1) caloric expenditure and (2) changes in morphometric parameters (waist circumference) in healthy human adults.

METHODS

Two separate randomized, double-blind, placebo-controlled, small clinical studies were conducted using a standardized L. barbarum fruit juice, GoChi, and assessing its effects on (1) resting metabolic rate (RMR) and postprandial energy expenditure (PPEE) as measured by indirect calorimetry after single-bolus intake of 3 doses of L. barbarum (30, 60, and 120 ml) and placebo; and (2) waist circumference and other morphometric changes in a 14-day intervention trial (120-ml daily intake) in the subjects (age = 34 years, body mass index = 29 kg/m(2)).

RESULTS

(1) A single bolus of L. barbarum intake increased PPEE 1 through 4 hours postintake over the baseline level in a dose-dependent manner and was significantly higher than the placebo group by 10% at 1 hour postintake of 120 ml (p < 0.05). (2) In a 14-day intervention trial, L. barbarum was found to significantly decrease waist circumference by 5.5 ± 0.8 cm (n = 15) compared with the preintervention measurements and placebo group at postintervention day 15 (p < 0.01). By contrast, the changes in the placebo group (n = 14) from preinterventions was 0.9 ± 0.8 cm, which was not statistically significant.

CONCLUSIONS

These results show that L. barbarum consumption increases metabolic rate and reduces the waist circumference, relative to placebo treated control subjects.