The Benefits of Vitamin D

What are Vitamins?

Vitamins are essential nutrients for life, which can be easily classified into two main groups: 
 

• Water-soluble vitamins, which include Vitamin B complex and Vitamin C. 
• Fat-soluble vitamins, which include Vitamins A, D, E, and K. Each of these plays distinct and vital roles, such as:
  • Vitamin A helps with vision, particularly in low-light environments.
  • Vitamin B plays key roles in three main areas: energy production (B1, B2, B3, B5, B7), protein synthesis (B6, B9, B12), and nervous system function (B1, B2, B3, B5, B6, B7, B9, B12).
  • Vitamin C is essential for collagen synthesis in both the skin and bones, and also helps produce carnitine, which aids in fat metabolism.
  • Vitamin D affects bone formation, and cell division in hair follicles, skin, and many other organs.
  • Vitamin E acts as an antioxidant, among other functions.

Why is Vitamin D Important?

     Vitamin D is responsible for bone formation and cell division in various organs. However, because medical science was not as advanced in the past as it is today, measuring Vitamin D levels in the blood was difficult. This made diagnosing Vitamin D deficiency highly challenging. Consequently, it was long believed that Vitamin D deficiency only affected the bones. Today, more detailed research has revealed that cells in almost every system of the human body require Vitamin D to help regulate cell division.

Furthermore, as testing for Vitamin D levels has become more widespread, we have learned that even in tropical and sunny countries like Thailand, Vitamin D deficiency is highly prevalent.

Vitamin D Deficiency and Its Impact on Bones

     If children suffer from a Vitamin D deficiency, they are at risk of developing rickets. In adults, it leads to osteoporosis. To understand the difference between rickets and osteoporosis, we must first understand the mechanism of bone formation.

1.  Bone Composition

     Our bones are composed of bone-forming cells making up only 2-5% of their volume, while the remaining 95% consists of protein in a semi-fluid state and minerals. These minerals include calcium, phosphorus, carbonate, magnesium, and sodium.

2.  Bone Formation

     Bone development begins as early as 5 weeks of gestation, starting with the formation of cartilage. This cartilage is gradually replaced by hard bone around the 7th week of pregnancy. Following this, bones continue to grow longer and larger, eventually halting their growth after birth as a person reaches late adolescence.

Even though bones stop growing in length during adulthood, they continue to undergo constant repair and remodeling throughout life in response to the weight bearing down on them. Therefore, when a bone fractures, it can still heal because bone cells remain alive and active, generating new bone to bridge and repair the fracture site.

What is Rickets?

     Rickets is a condition where a child's growing cartilage fails to be properly replaced by hard bone. As a result, the bones lack strength, causing them to bow or bend under the weight of the body. Therefore, Vitamin D is crucial for the formation of strong bones because it helps the body absorb two essential minerals: calcium and phosphorus. This absorption takes place in both the intestines and the kidneys. Consequently, if there is a Vitamin D deficiency, insufficient calcium and phosphorus intake, or kidney disease, the development of hard bone will be compromised.

Protein is Another Indispensable Component

     In addition to Vitamin D and these minerals, protein is another vital component. If you have the minerals but lack protein, bones cannot be built. Therefore, protein is key. I like to compare bone building to building a house. Just as constructing a pillar requires cement and rebar, protein is like the cement. It exists in the form of a fluid protein secreted by bone cells, which, when released alongside a specific hormone, works to draw calcium into the bones. Thus, the fluid protein acts as the cement, while the minerals (calcium, phosphorus, magnesium, and sodium) act as the steel rebar. Together, they make the bones strong. Consequently, if children do not consume enough protein, they will not grow tall, leading to a short stature condition.

As for adults, Vitamin D deficiency leading to osteoporosis is a complex topic that involves multiple bodily systems, which I will share with you in a future opportunity.

Effects of Vitamin D on Systems Beyond the Bones

Vitamin D affects cell formation across several bodily systems. Consequently, it impacts muscles, hair, and certain types of cancer as follows:

• Muscles: It increases muscle strength and improves balance, which helps prevent falls.
• Hair: Studies have found that cells at the hair root require more Vitamin D during the active hair growth phase. Experiments using topical Vitamin D on patients undergoing chemotherapy have shown it can help prevent hair loss associated with certain types of chemo.
• Cancer: Research indicates that Vitamin D helps maintain a healthy balance in cell division and cell death in certain organs, such as the colon, breasts, and prostate. It has been observed that individuals with extremely low Vitamin D levels face a higher risk of developing cancers in these organs.

Aside from these three areas, the effects of Vitamin D deficiency on other systems are not yet clearly established, even though many other cell types are known to utilize Vitamin D. We will need to keep monitoring new scientific developments in the future.

How Do You Get Vitamin D?

     Now that we know Vitamin D deficiency affects various organs—not just rickets or easily fractured bones—gentle morning 'sunlight' stands out as an excellent source to effectively stimulate Vitamin D production in the body.

Is It Possible to Get Vitamin D Without Getting a Tan?

     The answer is no, because the light wavelengths that cause tanning (UVA and visible light) always penetrate the atmosphere first. However, the light that synthesizes Vitamin D (UVB) is less able to penetrate glass or thin fabrics compared to other light types. Furthermore, UVB only penetrates the atmosphere when the sun is strong and positioned at the shortest perpendicular distance to the Earth's surface. Consequently, UVB reaches the Earth's surface in significant amounts between 10:00 AM and 2:00 PM. Outside of these hours, it depends heavily on the sun's intensity. During the rainy season, heavy cloud cover may block UVB entirely.

Tips for Proper Sun Exposure

Since modern lifestyles keep us indoors, preventing us from getting adequate outdoor sunlight, we barely receive any Vitamin D. However, we cannot simply sunbathe between 10:00 AM and 2:00 PM because the sun is too harsh. Doing so will not only darken the skin but can also cause sunburn, premature aging, and skin cancer. Therefore, we should:

• Avoid direct, intense sun exposure as it can cause sunburn or redness. Repeated overexposure should be avoided as it leads to wrinkled skin and increases the risk of cancer.
• Engage in outdoor activities under the shade of trees during peak UVB hours. This allows you to absorb reflected light, which is not overly harsh.
• Wear airy, comfortable clothing such as short sleeves or skirts. If you wear long sleeves and long pants that fully cover the skin, you will not receive any UVB light.
• Apply sunscreen to protect your face from UVB. However, if you apply it heavily to your arms and legs as well, they will also be blocked from receiving UVB.

If Outdoor Sun Exposure is Not Possible

     If your lifestyle requires you to stay inside buildings constantly, if your skin is very fair and shows no sign of sun exposure even on the limbs, or if you experience hair loss, muscle aches, or frequent cramps, you should have your Vitamin D levels checked. If they are low, you should seek treatment and take prescribed medication under a doctor's guidance. Do not purchase and consume Vitamin D supplements on your own without a blood test, as excessive intake can be toxic.

Preventing Rickets in Children

     For children, waiting until their limbs start to bow is already too late. We should look at the mother first. If a pregnant mother is deficient in Vitamin D, the newborn baby will be born with a deficiency as well. Therefore, mothers are encouraged to engage in outdoor activities as recommended. If a mother has had her Vitamin D levels checked and they are low, she should consult a physician for treatment. This ensures that the newborn will be healthy, strong, and develop normally for their age.

Another group that is frequently deficient in Vitamin D is individuals with obesity. This can stem from two main causes: limited outdoor physical activity, and the fact that Vitamin D gets sequestered and stored inside body fat, leaving very little circulating in the bloodstream. Consequently, less Vitamin D reaches the bones, muscles, and other organs.

For Individuals with Obesity

     In individuals with obesity, if Vitamin D levels are extremely low and they do not consume calcium-rich foods like milk, it can lead to muscle weakness, which further contributes to weight gain. It is common to see many individuals with obesity eating and then wanting to sleep, which might not be due to laziness but could actually be a symptom of Vitamin D and calcium deficiency. This issue can make weight loss attempts ineffective. I highly recommend addressing Vitamin D deficiency as part of weight management.

Is Vitamin D Found in Foods?

     Natural foods contain very little Vitamin D, which is usually insufficient to meet our daily requirements. Examples of foods that contain some Vitamin D include cod liver oil, dried Shiitake mushrooms (which have been exposed to UVB), and fatty fish like salmon, where Vitamin D is stored in the fish fat. While milk is high in calcium, it contains only a small amount of Vitamin D naturally. Some cold-climate countries, like the United States, fortify their milk with Vitamin D, which has significantly reduced Vitamin D deficiency among their population.

Conclusion

     Vitamin D deficiency is common in Thailand, especially among urban residents who have limited opportunities to spend time outdoors. This leads to weakened muscles and bones, as well as the risk of developing the other conditions mentioned above. Therefore, both children and adults should spend some time outdoors, but must avoid direct, intense sun exposure to protect their skin. If this is not possible and you experience symptoms of Vitamin D deficiency, you should have your blood levels tested rather than buying supplements to self-medicate.

Both children and adults should spend some time outdoors to prevent symptoms of Vitamin D deficiency, have their Vitamin D levels checked, and avoid self-medicating with over-the-counter supplements.

Edited

26/07/2023