What causes low 25-hydroxyvitamin D levels in adults?
Oct 12, 2022
Source: Cainiu Health
Dr. Wang Lei
Introduction
Low levels of 25-hydroxyvitamin D in adults may be caused by insufficient dietary intake of vitamin D, inadequate sun exposure, or abnormal liver function. Some individuals may have reduced vitamin D intake due to an unbalanced diet or picky eating habits. Infrequent sun exposure leads to decreased cutaneous production of vitamin D, and impaired liver function can affect the conversion of vitamin D into 25-hydroxyvitamin D.
Generally, low levels of 25-hydroxyvitamin D in adults may be caused by insufficient dietary intake of vitamin D, inadequate sun exposure, abnormal liver function, or other reasons.
1. Reduced dietary intake of vitamin D: Some individuals may have inadequate vitamin D intake due to an unbalanced diet or picky eating habits. In daily life, vitamin D can be supplemented by consuming foods rich in this nutrient, such as animal liver, lean meat, dairy products, and egg yolks.
2. Insufficient sun exposure: Ultraviolet rays from sunlight help convert 7-dehydrocholesterol in the skin into vitamin D. Lack of regular sun exposure reduces the skin's production of vitamin D. Appropriate sunbathing can help increase vitamin D levels. It is recommended to get one hour of sun exposure daily, preferably during spring and autumn. In winter, midday is ideal, while in summer, early morning before 9 a.m. or late afternoon after 5 p.m. is preferable. Combining sun exposure with physical activity can yield better results.
3. Abnormal liver function: 25-hydroxyvitamin D is formed in the liver through hydroxylation of vitamin D and plays a key role in regulating calcium and phosphorus metabolism in the body. Impaired liver function can affect the conversion of vitamin D into 25-hydroxyvitamin D.
