How can I protect my eyes from the harmful effects of oxidative stress? A well-balanced, varied diet, rich in antioxidant compounds, plays an important role in prevention. If there are not enough of them in the diet, it is necessary to consider appropriate supplementation. In the text, you will also learn more about free radicals themselves and about the effects of an oxidative-antioxidant imbalance and how exactly you should fight to restore it.
Under physiological (normal) conditions, there is an oxidative-antioxidant balance in the body. Its disturbance, and more precisely the predominance of oxidative processes, results in increased oxidative stress, which may initiate pathological processes and contribute, among others, to DNA damage, lipid oxidation and glucose.
It is true that the body is not helpless - it has a number of protective mechanisms at its disposal to prevent disturbance of the natural oxidative balance. However, increased and long-term production of reactive oxygen species can lead to depletion of antioxidant reserves.
The excess of free radicals causes, among others degradation of unsaturated fatty acids present in cell membranes. If the so-called After a chain reaction, lipids will peroxidate (oxidize), and then membranes, enzymes, and nucleic acids can be damaged. Antioxidants (antioxidant compounds) inhibit or slow down the oxidation of cellular components. Their operation most often consists in:
Which antioxidants protect the eyes against the effects of oxidative stress?
Carotenoids are a kind of protective shield against the effects of oxidative stress. These are chemical compounds that build into the structure of cell membranes and modify their properties. Astaxanthin is one of the most powerful antioxidants, which helps to maintain a rigid structure of the membrane, which increases the resistance of membranes to ROS and prevents excessive lipid oxidation.
The antioxidant properties of vitamins cannot be overlooked, e.g. vitamin C has a protective effect on blood vessels and body fluids (such as blood, intra- and extracellular fluids). It also protects the retinal photoreceptors from light damage and supports the regeneration of vitamin E - a powerful antioxidant known as the "vitamin of youth" that binds to cell membranes.
Membranes full of polyunsaturated fatty acids are the prime targets of ROS 'attack. Vitamin E helps to break free radical chain reactions, preventing excessive lipid oxidation and damage to protein structures. High levels of it in the blood may reduce the risk of macular degeneration.
Vitamin A and β-carotene (vitamin A precursor) protect lipids against oxidative damage. Research results indicate that lower concentrations of vitamins A and E promote the degeneration of retinal photoreceptors.
Omega-3 fatty acids (docosahexaenoic acid - DHA and eicosapentaenoic acid - EPA) inhibit the production of pro-inflammatory cytokines and the formation of oxidative stress; have anti-inflammatory, anticoagulant, anti-atherosclerotic and vasoconstrictive properties and improve the blood lipid profile.
Omega-3 fatty acids are extremely important for the health of the eye - they play a number of important functions in the retina, including structural, functional and protective functions. They actively participate in the visual process and prevent many eye diseases, incl. related to the aging process (AMD).
Selenium also has an antioxidant effect. The correct concentration of this element may prevent the development of neoplastic changes. Selenium also influences the metabolism of thyroid hormones.
Why is it so important?
Due to the so-called ocular symptoms, which most often occur in hyperthyroidism, but may also appear in patients with normal or underactive thyroid gland hormone function.
Mild ailments of this kind include tissue swelling, widening of the eyelid gap, and excessive tear production; in more severe cases, there is a risk of developing optic neuropathy or corneal ulceration and permanent loss of vision. In addition, zinc and selenium are involved in the metabolic processes of the retina and regulate the activity of its enzymes. Too little zinc intake can promote macular degeneration.