Goji berries (Lycium barbarum, wolfberry) grow on an evergreen shrub found in temperate and subtropical regions in China, Mongolia and in the Himalayas in Tibet. They are in the nightshade (Solonaceae) family. Goji berries are usually found dried. They are shriveled red berries that look like red raisins. Goji berries are rich in antioxidants, particularly carotenoids such as Beta-carotene and zeaxanthin. One of zeaxanthin's key roles is to protect the retina of the eye by absorbing blue light and acting as an antioxidant. Goji berries have been used for 6,000 years by herbalists in China, Tibet and India to: protect the liver, help eyesight, improve sexual function and fertility, strengthen the legs, boost immune function, improve circulation, and to promote longevity.
Amagase H, Nance DM. Lycium barbarum increases caloric expenditure and decreases waist circumference in healthy overweight men and women: pilot study. 1. J Am Coll Nutr. 2011 Oct;30(5):304-9.
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. Method: 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 border=0>. 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.