Chlorella vulgaris is a type of single-cell green algae. This edible microalgae has gained significant attention in recent years due to its purported benefits as a whole food supplement. Investigations indicate that this common freshwater algae, when taken as a dietary supplement, offers significant antioxidant protection, and may promote eye health.
Chlorella possesses an excellent nutritional profile. It’s high in protein, heart-healthy polyunsaturated fats (including essential omega-3 fatty acids), carbohydrates, vitamins and minerals. It is also a good source of the important carotenoid antioxidant pigment, lutein. Carotenoids are organic pigments found in certain plants. Beta-carotene is one example of a well known carotenoid. It’s responsible for the familiar orange color of carrots—and may account for the carrot’s reputation as a functional food that supports good vision.
In recent years, scientists have recognized that certain carotenoids, namely lutein and zeaxanthin, become concentrated in the eye to protect the retina from damage by high-energy blue light. Together, these pigments are referred to as “macular pigment”. Studies have shown that foods that are rich in these natural pigments help increase the density of the macular pigment. Clinical trials are presently underway, but it now appears certain that macular pigment helps protect the aging eye from damage that may cause conditions such as macular degeneration.
Macular degeneration is a serious condition resulting in blindness in the center of the field of vision (the macula of the retina). It commonly affects people over 50, hence its full name, age-related macular degeneration, or AMD. Most people diagnosed with AMD have the “dry” form. A far less common form, known as “wet” AMD does not appear to be related to macular pigments. Although AMD results in a loss of function in only a small portion of the retina, leaving peripheral vision intact, its impact is profound. The macula is largely responsible for detailed vision. Without a functional macula, it is difficult to see well enough to read or recognize faces.
Lutein and other carotenoid pigments are also believed to help prevent the formation of harmful compounds called advanced glycation end-products (AGEs). AGEs are formed when excess blood sugar reacts with proteins and other compounds in the body. AGEs are implicated in retinal damage related to diabetes. This condition, known as diabetic retinopathy, can progress to blindness, and affects a majority of people who have had diabetes for a decade or more. Chinese researchers concluded recently that nutrients from microalgae, including lutein and the omega-3 fatty acid, EPA (eicosapentaenoic acid), helped prevent the accumulation of AGEs in the retina. Microalgae such as chlorella vulgaris may, they added, be viewed as beneficial foods that may help prevent diabetic retinopathy.
A recent study examined the effects of six weeks of supplementation with Chlorella vulgaris on the antioxidant status of male smokers. Smokers are known to be under increased oxidative stress. Oxidative stress has been implicated as a risk factor for a broad range of illnesses. Antioxidants from the diet are known to help counteract oxidative stress, and are believed to help prevent some of the damage caused by oxidative stress.
Smokers who took 6.3 g Chlorella vulgaris per day had significantly higher levels of certain antioxidant compounds in their blood than men who took an inactive placebo. “Chlorella is an important whole-food supplement,” investigators concluded, “that should be included as a key component of a healthy diet.” [Lee SH 2010]