Vitamin D: So Abundant, Yet So Easy to Deficient In

Vitamin D: So Abundant, Yet So Easy to Deficient In

 

Vitamin D offers a wide range of health benefits. It helps the body absorb calcium, supports bone formation, and contributes to the health of the muscles, lungs, brain, heart, nervous system, and immune system. Despite the fact that the human body can naturally produce vitamin D through sunlight exposure, vitamin D deficiency is still increasingly common among Thai people today.

 

This may be due to changes in lifestyle and environment. Many people now spend most of their time indoors and have less exposure to sunlight. As a result, vitamin D deficiency has become more common. In addition to weakening the bones, inadequate vitamin D levels have also been associated with chronic health conditions such as diabetes, cancer, infections, and allergic diseases.

 

Why Does the Body Need Vitamin D?

 

The main role of vitamin D is to help the body absorb calcium and phosphorus from food and maintain normal levels of these minerals in the blood. These functions are essential for growth and for keeping bones and teeth strong. Vitamin D also helps prevent osteoporosis and low bone density.

 

In addition, vitamin D helps suppress parathyroid hormone, which is involved in bone breakdown. It also plays an important role in the immune system by helping the body defend itself against harmful invaders such as bacteria and viruses.

 

When the body lacks vitamin D, calcium absorption in the digestive tract decreases, bone mass is reduced, and the risk of fractures may increase. Vitamin D deficiency may also lead to serious complications such as low calcium and phosphorus levels in the blood, rickets in children, and osteoporosis in adults. It may also increase the risk of complications related to infections.

 

Factors and High-Risk Groups for Vitamin D Deficiency

 

Several factors may increase the risk of vitamin D deficiency.

 

Insufficient sunlight exposure is one of the most common causes. This may result from avoiding the sun or regularly using sunscreen with SPF, which reduces the skin’s ability to absorb ultraviolet rays needed for vitamin D production.

 

Air pollution, dust, and smoke can also reduce the amount of ultraviolet radiation that reaches the skin, which lowers the body’s ability to synthesize vitamin D.

 

Inadequate dietary intake is another contributing factor. Foods rich in vitamin D include oily fish such as sardines, trout, tuna, salmon, and mackerel, as well as milk and fortified cereals.

 

Older adults are at greater risk because the body’s ability to synthesize vitamins naturally declines with age. They also tend to spend less time outdoors.

 

People who are overweight or have excess body fat may also be at risk of vitamin D deficiency or insufficiency.

 

Other high-risk groups include pregnant or breastfeeding women, people with darker skin tones, those with intestinal disorders that affect fat absorption, patients with chronic pancreatitis, and those with stage 3 or 4 chronic kidney disease.

 

Recommended Daily Vitamin D Intake for Thai People

 

According to the Thai Recommended Daily Intake guidelines, the daily vitamin D requirement varies by age and condition:

๐ Infants under 12 months: 400 IU (10 micrograms) per day

๐ People under 70 years of age: 600 IU (15 micrograms) per day

๐ People over 70 years of age: 800 IU (20 micrograms) per day

๐ Women planning pregnancy: 400-600 IU per day

๐ Pregnant women in high-risk groups: 2,000-4,000 IU (50-100 micrograms) per day

 

How Can You Tell if You Are Deficient in Vitamin D?

 

The symptoms of vitamin D deficiency are often nonspecific. Some people may experience fatigue, weakness, bone pain, unexplained body aches, hair loss, frequent illness, depression, or anxiety. Others may have no symptoms at all.

 

For this reason, the best way to diagnose vitamin D deficiency is through a blood test that measures 25-hydroxyvitamin D [25(OH)D] levels. This test can often be included as part of an annual health check-up.

 

Vitamin D status is generally classified into three levels:

๐ Less than 20 ng/mL: vitamin D deficiency

๐ 20-30 ng/mL: vitamin D insufficiency

๐​ More than 30 ng/mL: sufficient vitamin D level

 

What Should You Do if You Have Vitamin D Deficiency or Insufficiency?

 

If you have low vitamin D levels, there are several ways to improve them.

 

Spending more time in the sun can help. Outdoor activity with sunlight exposure for at least 15 minutes, 2 to 4 times per week, may support vitamin D production. Suitable times are when the sun is not too intense, such as early morning from 6:00 to 8:00 a.m. or late afternoon from 4:00 to 6:00 p.m.

 

Eating foods rich in vitamin D is also important. Good sources include cod liver oil, liver, egg yolks, mushrooms, and fatty fish such as tuna, mackerel, and salmon.

 

Vitamin D supplements may also be recommended. The type and dosage should be selected by a physician based on each patient’s condition and individual needs.

 

Regular medical follow-up is also important, especially for people who are at high risk or who have already been diagnosed with deficiency.

 

Take Vitamin D Deficiency Seriously

 

Although vitamin D is something the body can produce naturally, deficiency remains surprisingly common. Because vitamin D is essential for bone health, immune function, and overall well-being, maintaining an adequate level is an important part of preventive healthcare. Early screening, proper nutrition, appropriate sunlight exposure, and medical guidance can all help reduce the risk of long-term complications.

 

 

 

 

source : Nakornthon Hospital

**Translated and compiled by ArokaGO Content Team