Sea buckthorn berries are one of the twelve berries rated highest for flavonol content.
Photo courtesy of Thomas S. C. Li, Ph.D., Agriculture and Agri-Food Canada
In the space race of the 1960s and 1970s, the Soviets had an inside track to keeping their astronauts in the peak of health: oil of the sea buckthorn (Hippophae rhamnoides). Used as a vitamin supplement and as protection from radiation, this plant was a routine part of space flight, and development of high-yielding varieties was a closely guarded state secret.
Yet few North Americans know of sea buckthorn. By contrast, in countries such as China and Russia, it has a rich history spanning more than 1,300 years. Its purported benefits range from its nutritional properties to a plethora of medicinal effects. Sea buckthorn is a thorny shrub with narrow willow-like leaves and yellow-orange berries. Its fruit yields pulp for juice, seed oil, and a yellow-orange dye for naturally tinting foods and cosmetics. The leaves make a robust tea.
Sea buckthorn berries contain more than 100 different nutrients and phytochemicals—vitamins, fatty acids, free amino acids, flavonols, and carotenoids. They are rich in carotene and vitamins C and E. Vitamin C concentration varies from 360 mg of vitamin C per 100 g of berries for the European subspecies H. rhamnoides to 2,500 mg of the vitamin per 100 g for the Chinese subspecies H. sinensis. (Compare this to fresh orange juice with 35 to 56 mg of vitamin C per 100 ml.) Carotene content ranges from 30 to 40 mg per 100 g of berries, and vitamin E concentration can be up to 160 mg per 100 g. Berries are also high in the trace mineral chromium, which works with insulin to help the body use sugar, and may also help to reduce high blood pressure.
A Finnish study reported in the Journal of Agricultural and Food Chemistry compared flavonol content in twenty-five edible berries. Sea buckthorn was among twelve berries rated as “high” (defined as greater than 50 mg per kg flavonol). It was especially rich in quercetin, with concentrations exceeding those of other popular berries such as blueberries, bilberries, strawberries, red raspberries, and currants. Flavonols may serve as antioxidants and anticarcinogens, and may lessen the risk of coronary heart disease, stroke, and lung cancer.
Sea buckthorn oil
Sea buckthorn seed oil is high in unsaturated linolenic and linoleic fatty acids. These essential fatty acids may help to relieve chronic eczema, cure dermatitis, and maintain healthy skin. The fatty acid profile, together with its high carotenoid content and vitamin E tocopherols, may be responsible for reported antimutagenic properties, therapeutic action on eye burns, stimulation of skin wound healing, and prevention and treatment of peptic ulcers. However, these therapeutic claims need to be confirmed through independent testing.
One of the first such studies from a Western country has probed the effects of sea buckthorn berry oil (SBO, seed plus berry pulp oil) on platelet aggregation. As reported in the Journal of Nutritional Biochemistry, Finnish and UK researchers found that orally administered SBO was linked to a reduction in blood clotting in men with normal blood lipid characteristics. Blood clotting is a risk factor in cardiovascular disease. The study is preliminary, having been conducted with only twelve men over a four-week period, but it does indicate that SBO may be a promising natural adjunctive form of therapy in preventing cardiovascular disease. SBO contains sterols, with sitosterol as the most abundant individual component. Sitosterol has been linked previously to the inhibition of platelet aggregation, while phytosterols in general (including sitosterol) are known to reduce plasma total and LDL cholesterol levels by affecting both absorption and synthesis of cholesterol. The oil also contains palmitoleic acid, which may have cholesterol- and triglyceride-lowering benefits as well as stroke-suppressing effects. The seed oil is noteworthy, too, because it absorbs strongly in the ultraviolet range, thereby providing a natural sunscreen.
An array of products
World interest in this plant has spawned an array of products derived from the juice, oil, and leaves. The major products, reported in the Journal of Agricultural and Food Chemistry, are seed oil, yellow pigment dye, and juice (both clarified and unclarified). The juice goes into mixed-juice drinks, nectars, and other fruit beverages. The berries are acidic in taste, not very sweet, with a mild and unique whey-like aroma. The oil and juice have been used as additives to foods such as candies, jams, jellies, chutneys, and vinegars, and to wine, beer, and liqueurs. They also can be incorporated into personal-care products such as cosmetics, lotions, soaps, shampoos, gels, conditioners, styling gels, and sunscreens, and into pharmaceutical or nutraceutical products such as vitamin supplements, oil capsules, flavone powder, and syrups. The leaves are used for leaf extract, tea, and animal feed. The yellow-orange pigment is used in food coloring and in pharmaceutical and cosmetic compositions.
This vast array of products testifies to the longstanding interest in sea buckthorn in other parts of the world. In Russia and China, sea buckthorn provides approved medicines and has been an established part of the pharmacopeia of those countries for centuries. Until recently in Canada, it has been planted mainly for shelterbelts, land reclamation, and enhancement of wildlife habitat, but efforts are now underway (e.g., in British Columbia and Saskatchewan) to initiate commercial cultivation of the species for other uses. Agriculture and Agri-Food Canada estimate that there is a potential annual demand for 10,000 kg of processed sea buckthorn oil in North America.
If you’re looking for sea buckthorn products, several North American manufacturers now have products on the Internet. Look for high-quality products, such as cold-pressed extracts, which retain phytochemical integrity better than solvent-extracted types. Also, products may need to be stored in the dark at cold temperatures to minimize degradation.
There are no reported cases of toxicity from sea buckthorn products, according to the International Centre for Research and Training on Sea Buckthorn (www.icrts.org). However, be careful to choose products that specify sea buckthorn, rather than just buckthorn. There are several unrelated buckthorn species (of the genus Rhamnus) from which medicinal bark extracts are derived, and which may irritate the intestinal tract. Thus, the U.S. Food and Drug Administration cautions against using certain diet teas containing buckthorns.
Gina Mohammed, Ph.D., is a plant physiologist living in Sault Ste. Marie, Canada. She is the author of, Catnip and Kerosene Grass—What Plants Teach Us About Life (Candlenut Books, 2002).