Adding rosemary to a dish while cooking may help to protect your eyes from macular degeneration. Researchers at the Sanford-Burnham Medical Research Institute have published a study that shows a connection between carnosic acid, a substance found in rosemary, and eye health.
Age-related macular degeneration is the most common eye disease in the United States. Previous studies have shown that the disease can be slowed by chemicals that fight free radicals. Free radicals are compounds that can damage membranes and interfere with cell processes, leading to diseases like macular degeneration.
To test the relation between carnosic acid and macular degeneration, researcher Stuart A. Lipton, M.D., Ph.D. and his team exposed lab cultures of retinal cells to hydrogen peroxide. This simulated the type of oxidative stress that can contribute to macular degeneration. The cells that had been treated with carnosic acid produced an enzyme that lowered the levels of oxidative substances, thus protecting the eye.
The team went on to test the relationship between carnosic acid and damage caused to the eye by light. When tested, rodents that had been pre-treated with the acid had a thicker outer nuclear layer in their eyes, suggesting that their photoreceptors (the part of the eye that converts light into images) were better protected.
Other Protective Compounds to Protect Against Macular Degeneration
These new findings add rosemary to a growing list of herbs and spices that have health benefits for those who consume them. Some other compounds found in food can also be useful in the fight against macular degeneration:
Lutein – A chemical found most abundantly in dark green leafy vegetables such as kale, spinach, collard green and turnip greens, lutein is one of the foremost combatants in the fight against macular degeneration. In her book Foods That Fight Disease by Laurie Deutsch Mozian, she states that a mere six milligrams of lutein each day in the diet can decrease your risk of acquiring age-related macular degeneration by as much as 43 percent.
Even if you already have some degree of macular degeneration, increasing the amount of lutein you get each day can help to increase the density of macular pigment. Dr. Mark Grossman of the Integral Health Center in Rye and New Paltz, NY, believes that anyone over 50 should take lutein supplements. He says "Macular degeneration may be stabilized or reversed with nutritional intervention. By far, [lutein is] the number one nutritional treatment for the disease." Drs. Marc R. Rose, MD, and Michael R. Rose, MD, in their book "Save Your Sight, note "A few weeks after consuming more lutein-rich foods or lutein supplements, some normal-sighted people report less glare, improved color vision, and sharper vision."
Zeaxanthin – According to the Life Extension Foundation's Disease Prevention and Treatment, zeaxanthin works "as a shield or filter that helps to absorb harmful UVB light and dangerous free-radical molecules, both of which threaten the retinal tissue." Like lutein, zeaxanthin can be found in dark green leafy vegetables, but it is also found in eggs, broccoli, zucchini, peas and Brussels sprouts.
Beta-carotene – The precursor to vitamin A, beta-carotene has long been known to be eye-healthy. Remember your mother telling you to eat your carrots? Carrots and other orange and yellow colored foods such as pumpkin, butternut squash and sweet potatoes are high in beta-carotene and can help protect against the development of macular degeneration.
Omega-3 fatty acid – Another of the many benefits of increased omega-3 intake is that it helps to prevent age-related macular degeneration. A study performed by researchers at Harvard University analyzed the diets of over 38,000 women in their 40s. Those who ate oily fish (the kind high in omega-3 fatty acid, such as salmon, sardines, herring and mackerel) once or more per week had a 42% lower risk of age-related macular degeneration. However, it was only the omega-3 containing docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) that showed a protective effect, not alpha-linoleic acid (ALA), the omega-3 found in plant-based fatty acids such as linseed. If you are taking any kind of blood thinner such as warfarin or aspirin, consult with your doctor before taking an omega-3 supplement, as fish oil may increase your risk of bleeding.
The findings about rosemary are another confirmation that the foods we eat are intimately connected with the state of our health. Countless other studies will continue to explore these connections, giving people the information they need to make good decision about what they choose to eat, both for the sake of their taste buds and their health.