What is Goji Berry? (Also known as Lycium barbarum)
Goji berry is the popular name given to the small red fruit Lycium barbarum, from the family Solanaceae. Goji berries are a well-known traditional Chinese medicine1 and are widely consumed in China and by Chinese abroad6. However, recently they have been widely used as a nutritional food product5. Their consumption is thought to confer a large variety of beneficial effects, such as reducing blood glucose and serum lipids, antioxidant, immune-modulation, neuroprotection, and anti-inflammatory activity2-4.
Where Do Goji Berries Come From?
The original habitat of L. barbarum is not definitively established but is probably to be found in the Mediterranean Basin7. Today the plant is widely distributed in warm regions of the world, in particular in the Mediterranean area, Southwest and Central Asia. It is also cultivated in North America and Australia as hedge plant8. The majority of commercially produced goji berries come from plantations of L. barbarum in the Ningxia Hui Region in northcentral China and the Xinjiang Uyghur Region in western China5.
Goji Berry Benefits
One of the issues in assessing the merits of the health benefits of goji berry has been the poor quality and general lack of research5. Much of the original clinical data on goji berry has only been published in national Chinese journals which are not accessible. Many studies have been small-sized and not adequately controlled. Moreover, most literature is only available in abstract form since original data from Chinese publications are difficult to access5. In most cases it is not clear whether L. barbarum or L. chinense has been used in these studies5.
Having said this, there are a number of recent independent studies that are better quality and provide some reassurance of the general health benefits of Goji berry. A recent series of studies has linked the high content of taurine in Goji berries with it beneficial effect on diabetic retinopathy, a preventable microvascular diabetic complication that damages human retinal pigment epithelial cells9, 10. In close connection with this is a recent study suggesting that Goji berry may be helpful for eyesight. Goji berry is the richest natural source of the antioxidant carotenoid, zeaxanthin, which composes a part of the eye called the preretinal pigment. Daily dietary supplementation with goji berry for 90 days was shown to increase plasma zeaxanthin and antioxidant levels as well as markers of vision in elderly subjects11.
One recent study found that Goji berry consumption increases metabolic rate after a single bolus and reduces the waist circumference after 14 days consumption, relative to placebo treated control subjects16.
In another study, ingestion of 50 g/day of Goji berries in 25 elderly people for 10 days increased superoxide dismutase and hemoglobin and decreased blood lipids significantly12. Recently, in a first double-blind study performed outside China, the general effects of GoChi™, a commercial Goji juice, were investigated in young healthy adults. Various parameters were assessed by a questionnaire. Blood pressure and body weight were also monitored. The study concluded that consumption of GoChi™ for 14 days increased subjective feelings of general well-being and improved neurological performance as well as gastrointestinal function. However, the small size of the study (N = 34) and the subjective assessment of most parameters must be critically pointed out13.
In a follow-up double-blind study (N = 30) sponsored by the supplement manufacturers, the authors investigated the effect of GoChi™ on serum antioxidant markers in healthy Chinese adults aged 55–72 years. A significant increase of superoxide dismutase and glutathione peroxidase by 8.4 and 9.9% respectively and a concomitant decrease of malondialdehyde by 8.7% were observed after 30 days14. These data are in agreement with previous observations15 and may be indicative of possible beneficial effects in oxidative stress and age-related conditions.
Negative Side Effects of Goji Berries
There is a recent report in the literature of a case of hepatotoxicity related to the use of Goji berry in a 60-year-old woman. This particular women had been consuming Goji berry tea 3 times a day over the previous ten days upon a friend’s recommendation (one handful of berries each cup), but no other medication17. Another study has documented 2 cases of allergic reaction following Goji berry ingestion18. There is also a single case of photosensitivity due to consumption of Goji berries reported in the literature19. These random reports of negative side effects from the consumption of Goji berries may be linked to the poor regulation and standardisation that exists with regard to the quality and consistency of Goji berries.
Goji Berry Recommended Dosages & Timing
Because Goji berry is a food, there are no strict recommendations on dosages and timing. However, most people consume a handful or two at a time, which amounts to 5-10 grams.
Goji Berry Supplements
Goji berries are often sold on their own, either bagged as whole berries or as an extract in supplemental or liquid form.
Stacking Goji Berry
Goji berries are not typically stacked with other ingredients. However, it is not uncommon to find them mixed with other superfoods such as acai berry.
Goji Berry Safety
In a book on Chinese materia medica, measures of toxicity of a water extract of Goji berry confirm the virtual absence of toxicity of the fruit20. However, while there is no risk with cultivated plants, some caution is advised with samples of unknown origin, since confusion with morphologically similar Solanaceae fruits cannot be excluded.
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3. Peng X, Tian G. Structural characterization of the glycan part of glycoconjugate LbGp2 from Lycium barbarum L.. Carbohydr Res. 2001;331:95–9.
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9. Song MK, et al. Lycium barbarum (Goji Berry) extracts and its taurine component inhibit PPAR-g-dependent gene transcription in human retinal pigment epithelial cells: Possible implications for diabetic retinopathy treatment. Biochemical Pharmacology. 2011;82:1209–1218.
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11. Bucheli P, et al. Goji berry effects on macular characteristics and plasma antioxidant levels. Optometry and Vision Science. 2011;88(2):257–262.
12. Li W, Dai SZ, Ma W, Gao L. Effects of oral administration of wolfberry on blood superoxide dismutase (SOD), haemoglobin (Hb) and lipid peroxide (LPO) levels in old people. Chin Tradit Herb Drugs. 1991; 22:251-268.
13. Amagase H, Nance DM. A randomized, double-blind, placebo-controlled, clinical study of the general effects of a standardized Lycium barbarum (Goji) juice, GoChi™. J Altern Compl Med 2008; 14: 403–412.
14. Amagase H, Sun B, Borek C. Lycium barbarum (goji) juice improves in vivo antioxidant biomarkers in serum of healthy adults. Nutr Res. 2009;29:19–25.
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16. Amagase H, & Nance DM. Lycium barbarum increases caloric expenditure and decreases waist circumference in healthy overweight men and women: pilot study. J Am Coll Nutr. 2011;30(5):304-309.
17. Arroyo-Martinez Q, et al. Lycium barbarum: a new hepatotoxic “natural” agent? Digestive & Liver Disease. 2011;43(9):749.
18. Monzón Ballarín S, et al. Anaphylaxis associated with the ingestion of Goji berries (Lycium barbarum). J Investig Allergol Clin Immunol. 2011;21(7):567-70.
19. Gomez-Burnal S, et al. Systemic photosensitivity due to Goji berries. Photodermatol Photoimmunol Photomed. 2011;27(5):245-247.
20. Chang HM, But PPH, Yao SC,Wang L, Yeung SCS. Pharmacology and applications of Chinese Materia Medica, volume 2. New Jersey, London, Singapore, Hong Kong:World Scientific; 2001.