Lycium
Scientific Names: Lycium barbarum Other Common Names: Tibetan goji berry, wolfberry, bastard jasmine, common matrimony vine, prickly box, Duke of Argyll’s tea tree, tea tree. Note: do not confuse with tea tree oil (Melaleuca alternifolia) Overall Safety: 😊
Therapeutic Efficacy and Considerations:
Age-Related Macular Degeneration (AMD): 😐 The clinical efficacy of taking lycium supplements has never been examined. One human trial has been conducted that demonstrated that lycium intake increases plasma zeaxanthin levels. Epidemiological studies and some clinical trials suggest that increased zeaxanthin may protect against retinal damage and development of age-related macular degeneration. More studies of lycium are warranted, but at this time, it is not possible to recommend lycium supplements over obtaining zeaxanthin in the diet or via zeaxanthin supplements. Dose: not determined; trial used 15 g/day of dried berries.
Note: Lycium berries, more commonly called goji berries, are becoming an increasingly popular food/snack item in the U.S. See Drug Interactions section.
Chemistry/Pharmacology: Lycium berries contain beta-sitosterol, betaine, beta-carotene, niacin, pyridoxin, zeaxanthin, B vitamins, gamma-aminobutyric acid, and cerebroside. Beta-sitosterol has the ability to reduce cholesterol levels by preventing its absorption in the gastrointestinal tract. Betaine has uterine stimulant and diuretic properties. The cerebroside constituent found within lycium berries may have hepatoprotective properties, while polysaccharide extracts have been shown to have significant effects on cancer cells and tumor growth. Lycium may have benefit over other antioxidant sources providing zeaxanthin, as it seems to have increase accumulation in the central fovea of the retina.
Drug Interactions: Lycium can inhibit CYP2C9 and increase levels of drugs metabolized by CYP2C9, including warfarin, diazepam, and estradiol.
Contraindications/Precautions: Pregnancy/lactation (due to betaine content, an emmenagogue and abortifacient, large doses are likely unsafe).
Adverse Effects: None reported; clinical experience is limited.