Enjoy the Sun Safely

The sun is a known energy source for our planet and is essential for the continuation of life. One of the benefits of sunlight for humans is its role in producing vitamin D. However, it should be noted that excessive exposure to the sun can lead to certain health problems.

What is the Role and Importance of Vitamin D?

Vitamin D is a fat-soluble vitamin that strengthens bones and teeth, preventing bone fractures and osteoporosis. Vitamin D deficiency can lead to bone thinning, fractures, and muscle weakness.

Are There Other Benefits of Vitamin D in the Body Besides Bone Health?

Recent studies have shown that vitamin D is utilized in almost all cells and tissues in the body. It has been suggested that vitamin D could be crucial for preventing cancer, supporting the immune system, and maintaining cardiovascular health. Vitamin D deficiency has been associated with increased risks of cardiovascular diseases, cancer, infections, neurological damage, type 1 diabetes, multiple sclerosis, and rheumatoid arthritis, particularly when levels fall below 20 ng/mL. Studies have demonstrated a 60% increase in heart disease, twice the risk of heart attack, and three times the risk of elevated blood pressure when vitamin D levels drop below 15 ng/mL. However, there is no study confirming that vitamin D supplementation reduces the risks of these diseases.

Moreover, there have been discussions about the relationship between vitamin D deficiency and the severity of COVID-19. For instance, it has been claimed that those with low vitamin D levels experience more critical illness and encounter more intensive care issues during COVID-19.

Sources of Vitamin D

Vitamin D is synthesized in the skin under the influence of ultraviolet B rays from sunlight. Additionally, it can be obtained from certain foods such as red meat, fatty fish, eggs, and fortified foods.

Which is More Effective: Vitamin D Produced in the Skin or Vitamin D from Food?

The primary source of vitamin D is sunlight, as a significant portion of the body’s vitamin D comes from the synthesis in the skin rather than dietary intake. Factors affecting the production of vitamin D in the skin should be considered to address deficiencies adequately.

Factors Affecting Vitamin D Synthesis in the Skin:

1. Seasonal Variation: Vitamin D levels may fluctuate seasonally, with an expected increase between March and October and a decrease in the fall and winter months. UV ray levels are highest during the summer.
2. Age: Vitamin D production decreases with age. Therefore, the elderly are more dependent on dietary sources of vitamin D.
3. Sunscreen Use: Increased use of sunscreen will reduce vitamin D production.
4. Skin Color: As skin color darkens, vitamin D production decreases.
5. Geographic Location: UV ray levels increase as one moves towards the equator and at higher altitudes.
6. Time of Day: The highest exposure to UV rays occurs around noon.

Why Does Vitamin D Deficiency Occur?

Vitamin D deficiency can result from reduced synthesis in the skin, decreased absorption in the intestines, inadequate dietary intake, breakdown in the liver, side effects of various medications, and reduced activation in the kidneys and liver. Factors contributing to reduced skin synthesis include insufficient exposure to sunlight, dark skin color, and excessive use of sunscreen.

Who is at Risk for Vitamin D Deficiency due to Insufficient Sun Exposure?

Since the majority of vitamin D in the body is produced through exposure to sunlight, individuals with insufficient sun exposure are at greater risk. Identifying target populations for sunlight deficiency should be approached with caution due to the associated health implications and burdens. Those at risk include:

1. Elderly individuals, especially those residing in nursing homes or long-term care facilities.
2. Individuals unable to leave their homes due to chronic illnesses.
3. Individuals spending most of their time indoors or working indoors.
4. Those living at higher latitudes, with an increased risk beyond the 42nd parallel north. (Turkey is located south of the 42nd parallel, reducing this risk.)
5. Those consistently wearing protective clothing.
6. Individuals with limited sun exposure for sociocultural reasons.

How Common is Vitamin D Deficiency?

Although the frequency of vitamin D deficiency has decreased with the addition of fortified dairy products to the diet, it is still observed in the population. Studies have shown seasonal variability in vitamin D deficiency, with prevalence increasing to around 40% in winter and decreasing to about 10% in summer. In some ethnic groups, the prevalence can rise to 75%.

How is the Diagnosis Made?

Vitamin D deficiency can be assessed by measuring the level of 25-hydroxy vitamin D in the blood. However, not everyone needs to have their vitamin D levels measured, and testing is recommended only for those at risk of deficiency.

How Can Vitamin D Deficiency be Prevented?

Vitamin D deficiency can be prevented by exposure to sunlight without protection. Reasonable exposure to sunlight between 10:00 AM and 3:00 PM can produce twice the amount of vitamin D obtained through diet. However, during this period, the side effects of the sun will also increase. Care should be taken to balance between unwanted and beneficial effects.

Vitamin D synthesis is expected to be higher between March and October, especially around noon, and direct exposure of bare areas such as arms and hands to sunlight is more effective for vitamin D production.

Should I Take Supplements?

The daily requirement for vitamin D is approximately 600-800 IU. If adequate vitamin D is not obtained through sunlight and diet, supplementation may be necessary. The dose and method of intake should be discussed with a doctor. It should be remembered that excessive intake of vitamin D can lead to other diseases.

Are There Risks Associated with Sun Exposure?

While sunlight is necessary for a healthy life, there are potential dangers associated with excessive exposure to sunlight. Two well-known risks are skin cancer and sunburn. Additionally, harmful effects such as cataract development and premature skin aging may occur.

Those with a family history of skin cancer, a tendency to develop burns rather than tan, fair skin, numerous moles and freckles, red hair, or immune system suppression should be especially cautious.

The frequency and duration of time spent under the sun will affect the occurrence of these risks. It is advisable to limit exposure to strong sunlight and preferably stay in the shade. Even on cloudy days, prolonged exposure to daylight can result in burns.

Reflective surfaces like snow, sand, and water can intensify sunlight, increasing the risk of burns and eye damage.

How Can We Protect Ourselves from the Harmful Effects of the Sun?

To protect against harmful effects of the sun, such as skin cancer and burns, clothing, hats, sunscreen, and sunglasses should be used. Areas of the body that are more sensitive to the sun, such as the back, abdomen, and shoulders, should be treated with extra care. Fabrics that do not allow sunlight to pass through can be preferred for clothing. Hats should provide shade for the face, ears, and neck. Sunscreen is not an alternative to shade protection and appropriate clothing. It can be used as a supplement, and effective use requires repeated and careful application. Approximately 35 mL or 6-8 teaspoons of sunscreen will be needed for good protection. The thinner the layer applied to the skin, the less protective it will be. Reapplication may be necessary after sweating