Cheryl Myers, chief of education and scientific affairs at EuroPharma, Inc. noted that recent research is promising for the use of seed oils for vision health.

She pointed to a Japanese study in which participants worked at a computer for two hours. The individuals in the black currant group noticed an improvement in visual acuity, including better focus and less time to adapt from dark to light. They also didn’t experience the back and neck stiffness and eye fatigue so common to working at a computer. Conversely, those taking the placebo experienced false nearsightedness when shifting their focus, and didn’t notice a reduction in fatigue. In another study focused solely on muscle fatigue and stiffness due to typing, those in the black currant group noticed less soreness, which researchers attributed to the effect of anthocyanins on peripheral muscles.

Black currant helps to stop the increased ocular pressure (IOP) commonly seen as a result of aging. In a clinical study published in the Journal of Ocular Pharmacology and Therapeutics, black currant anthocyanins significantly decreased IOP in just two weeks. The researchers concluded that this botanical helps induce a “beneficial decrease in IOP levels in healthy subjects as well as in patients with glaucoma.” “In other words, black currant anthocyanins can help preserve your eyesight and prevent eye disease,” Myers noted.

Black currant also strengthens the structure of the tiny blood vessels in the eyes, she added. A Japanese clinical study found that black currant extract slowed the deterioration of the visual field in those already diagnosed with open-angle glaucoma (OAG). According to the Glaucoma Research Foundation, OAG is the most common form of the disease and affects four million Americans. It is a condition in which clogged drainage canals cause a buildup of pressure in the eye, which damages the optic nerve. The same study showed that black currant anthocyanins also normalized serum levels of endothelium-1, a protein involved in blood vessel constriction.

“Additionally, I think that sea buckthorn, particularly the clinically studied extract we feature in our Omega7 Eye Relief product, SBA24, is a must for healthy eyes,” Myers said. “SBA24 includes both the seed oil and the pulp extract for the full benefits of the plant. It is also supercritical CO2 extracted with no solvents.”

When you have dry eyes, one of two things is happening: you either can’t produce enough tears or moisture to keep the eyes from feeling dry, (called an “aqueous deficient” dry eye) or your eye moisture levels start off normal, but the tear film isn’t healthy enough to prevent the eyes from drying out, (known as an “evaporative” dry eye), Myers noted. In a double-blind, randomized, placebo-controlled clinical study published in the Journal of Nutrition, one hundred men and women aged 20 to 75 who were experiencing dry eyes (and half of them used contact lenses) were given either SBA24 sea buckthorn or a lookalike placebo.

After three months, the redness and burning associated with dry eyes was much lower in the sea buckthorn versus the placebo group. In other similar studies, those using sea buckthorn had a much better fatty acid composition of their tear film than those in the placebo groups.

The researchers using the SBA24 sea buckthorn extract believe that reducing inflammation is critical because inflammation tends to dry out the eyes—and keep them dry. Research shows that the omega fatty acids in sea buckthorn work together to both reduce inflammation and boost tear secretion at the same time. Fatty acids—and a healthy fatty acid balance—also help build tears that lubricate the eye and prevent moisture loss. We know that people with healthy eyes have higher levels of certain fatty acids in their tears than people who suffer from dry eyes.

References:
Nakaishi H, Matsumoto H, Tominaga S, Hirayama M. Effects of black current anthocyanoside intake on dark adaptation and VDT work-induced transient refractive alteration in healthy humans. Altern Med Rev. 2000 Dec;5(6):553-62.

Matsumoto H, et al. Effects of blackcurrant anthocyanin intake on peripheral muscle circulation during typing work in humans. Eur J Appl Physiol. 2005 May;94(1-2):36-45.

Ohguro H, Ohguro I, Yagi S. Effects of black currant anthocyanins on intraocular pressure in healthy volunteers and patients with glaucoma. J Ocul Pharmacol Ther. 2013 Feb;29(1):61-7.

“Symptoms of Open-Angle Glaucoma.” Glaucoma Research Foundation. Available at: www.glaucoma.org/glaucoma/symptoms-of-primary-open-angle-glaucoma.php. Accessed: April 29, 2014.

Matsumoto H, Nakamura Y, Iida H, Ito K, Ohguro H. Comparative assessment of distribution of blackcurrant anthocyanins in rabbit and rat ocular tissues. Exp Eye Res. 2006 Aug;83(2):348-56.

Larmo PS, Järvinen RL, Setälä NL, Yang B, et al. Oral sea buckthorn oil attenuates tear film osmolarity and symptoms in individuals with dry eye. J Nutr 2010;140(8):1462-8.

Järvinen RL, Larmo PS, Setälä NL, Yang B, Engblom JR, Viitanen MH, Kallio HP. Effects of oral sea buckthorn oil on tear film Fatty acids in individuals with dry eye. Cornea. 2011 Sep;30(9):1013-9. doi: 10.1097/ICO.0b013e3182035ad9.

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