Despite being known as the "sunshine vitamin," vitamin D deficiency is more common than previously believed. Recent research indicates that about 15% of healthy adults in Brazil have insufficient levels of vitamin D, while more than 50% of the Spanish population experiences a deficiency. The trend persists even in countries with abundant sunlight, indicating a global health concern.
Vitamin D plays a crucial role in maintaining overall health. It contributes to bone health throughout life and is essential for strengthening bones, regulating the immune system, and improving muscular performance. One of the most important functions of vitamin D is to facilitate the absorption of calcium and phosphorus in the intestine, which are essential nutrients for maintaining the health of bones, teeth, and muscles. Low vitamin D levels primarily hinder the proper absorption of calcium, leading to weakened bones and an increased risk of conditions like osteoporosis.
The body produces vitamin D from direct sunlight on the skin when outdoors, primarily under the influence of UV-B radiation, with 80% to 90% of its production occurring this way. The best and easiest source of vitamin D is sunlight, and with just 5 to 15 minutes of direct sun on the arms and face three times a week, it is possible to cover a good part of daily vitamin D needs, as long as one is careful not to get sunburned.
However, factors such as the use of sunscreen, clothing, skin color, age, geographical location, and the time of year greatly influence the body's ability to produce vitamin D. People with darker skin are more prone to vitamin D deficiency because melanin absorbs ultraviolet rays before they can convert 7-dehydrocholesterol into cholecalciferol (vitamin D3). "People with darker skin need higher doses of vitamin D," explained Antônio Carlos do Nascimento. Elderly people also have a lower capacity for production and absorption of vitamin D. "Women over 70 years old should spend more time in the sun because cutaneous synthesis is lower by 75%," emphasized health experts.
In addition to sunlight exposure, vitamin D can be obtained through certain foods and supplements. Foods rich in vitamin D include fatty fish such as salmon, tuna, and sardines, egg yolk, liver, and mushrooms. Some products like milk, plant-based drinks, cereals, and certain juices are fortified with vitamin D. However, increasing vitamin D levels through food alone is not an easy task, and even with an adequate diet, it is difficult to cover all the necessary vitamin D solely through food.
Due to potential deficiencies, vitamin D supplements are an effective solution for those who do not receive enough sun exposure. Supplementation is ideal for people who cannot maintain normal vitamin D levels through sunlight alone, including the elderly, individuals with darker skin, those who frequently use sunscreen, and people with certain chronic diseases or absorption problems. It is important not to self-medicate with vitamin D; individuals should always follow the indications of a health professional to avoid potential harm from excessive intake.
Excessive vitamin D intake can lead to toxicity, dangerously elevating calcium levels in the blood and causing serious side effects, such as nausea, weakness, mental confusion, and kidney impairment. "Vitamin D is a fat-soluble vitamin, so if more than the necessary amount is ingested, it is not excreted and accumulates in fatty tissue, which is unfavorable for health," warned health specialists.
Vitamin D deficiency has been linked to various health issues beyond bone health. It affects mood and may worsen symptoms of seasonal affective disorder (SAD), including low mood, depression, or anxiety. Vitamin D may have positive effects on mood. There is also a correlation between bone pain or muscle pain and low vitamin D levels. Frequent infections or colds may indicate a vitamin D deficiency, as vitamin D helps the immune system function properly and reduces inflammation.
Certain populations have higher needs for vitamin D, including pregnant women. During pregnancy, vitamin D deficiency is related to complications both for the mother and the fetus. It is also associated with an increased risk of premature birth and low birth weight. In elderly people, the deficiency of vitamin D is associated with osteoporosis and risk of fractures. Other studies suggest that vitamin D may help prevent autoimmune diseases and protect against some types of cancer, including colorectal cancer.
Assisted by a news-analysis system.