LED lamps, television and computer screens emit a light that at first glance seems white. In fact, most of the light emitted by these devices is blue. Blue light has benefits, such as improving memory and attention, but, if in excess, it can damage the retina and cause, in the long run, degenerations such as macular degeneration. Of course, we can, where possible, apply filters to blue light, such as special lenses for glasses, especially if our work requires spending many hours at the computer. But nutrition also plays a pivotal role in the fight against retinal diseases. For example, spinach can strengthen the eye and protect it from damage from blue light. This is what emerges from a scientific research recently published by a Japanese team (Ozawa et al, Nippon Ganka Gakkai Zasshi, 2016).
Lutein and blue light
Some substances, such as lutein, are powerful antioxidants, useful to protect eyesight and prevent age-related damage to the retina. In particular, lutein, together with zeaxanthin, constitutes the pigment of the macula, the central part of the retina. Well, this pigment filters the blue light that reaches the retina, protecting it from the damages that could occur in the long run. Lutein is not synthesized by the human body but must be introduced with a varied diet, which also includes foods rich in lutein such as spinach, carrots and other leafy green vegetables.
The experiment
In order to demonstrate the beneficial action of spinach on the retina, the Japanese scientists, in the study we are talking about today, recruited 11 non-smokers, between 21 and 45 years old. The researchers asked the volunteers to eat 75 grams of frozen spinach every day for two months in order to consume 10 milligrams of lutein daily. Before and after the experiment, all study participants underwent eye examinations and blood tests in order to assess the presence of lutein in the blood circulation and in the retina. In particular, the optical density of the macular pigment was evaluated, which is a measure of how much pigment is present in the eye. Low pigment values indicate an increased risk of developing maculopathy.
The lutein of spinach protects the retina
What emerged at the end of the study is that the constant intake of spinach has increased the density of pigment in the retina and also the amount of lutein in circulation. More lutein means a greater filter of blue light and therefore a more powerful protection against damage from this type of light. Not only that, eyesight has also improved following the daily intake of spinach.
