The Foundation of Eye and Skin Health: Vitamin A

Natural Sources, Function in the Body, and Cooking Techniques

Among the vitamins essential for a healthy life, the fat-soluble group (vitamins A, D, and E) holds an important place. These vitamins benefit the body when they are present in fat and consumed with fat. Vitamin A, one of the important members of this group, does not occur alone in nature. Humans obtain this vitamin from two main sources: through proteins called 'retinol' from animals and through 'beta-carotene' from plants.

Retinol, a precursor to vitamin A, is found in liver, egg yolk, butter, milk, and dairy products. Plant-based beta-carotene is generally found in dark-colored foods, vegetables like sweet potatoes, eggplant, and spinach, and most prominently in carrots. For example, consuming grated carrots with olive oil and lemon can have positive effects on vision due to the fat-soluble nature of vitamin A. Therefore, the retinol and beta-carotene consumed are actually precursors to vitamin A.

These precursor substances, taken into the body, pass through the digestive system and are stored in the liver. When the body needs vitamin A, it is combined with proteins derived from cholesterol in the liver, released into the blood, and transported to the relevant organs. The eye and retina are at the forefront of these organs; vitamin A is the building block for the formation of visual pigments (rhodopsin) in the retina. Additionally, vitamin A plays a crucial role in the regeneration of the epidermis, the outermost layer of the skin, in bone tissue, and in the functions of reproductive organs. In its absence, severe dryness, flaking, and shedding can be observed on the skin.

Since vitamin A is stored in the liver, uncontrolled supplementation from external sources can lead to the risk of reaching toxic doses when combined with the existing stores in the liver. The excess of this vitamin, which cannot be excreted from the body because it is fat-soluble, can be harmful. When approaching toxic levels, symptoms such as nausea, headache, and a tendency to bleed due to its blood-thinning effect may occur. For this reason, vitamins should be considered as supportive elements that require careful control, rather than miraculous solutions.

Cooking techniques also play a significant role in preserving the benefits obtained from food. Even if individuals believe they are eating healthily, incorrect cooking methods can lead to vitamin loss. Practices such as prolonged sautéing with onions and oil, prolonged frying or boiling, cooking with the lid off, and finely chopping vegetables and letting them sit can lead to vitamin deficiencies. To avoid losing these valuable substances from nature, lighter, slow-cooking techniques, partial baking, or steaming methods should be preferred.