#千万IP创科学普# Vitamin D, familiar yet unfamiliar

When parents take their babies to get vaccinations, they are told to supplement their babies with vitamin D. But what is this, what is its function, how to take it, how long can it be taken, and are there any side effects? With these questions, let's talk about the relevant issues of vitamin D today.

What is Vitamin D ?

Vitamin D is also known as the anti-rickets vitamin. Its main function is to regulate calcium and phosphorus metabolism, promote intestinal calcium and phosphorus absorption and bone calcification, and maintain the balance of blood calcium and phosphorus. When the human body lacks vitamin D, rickets, osteomalacia, osteoporosis, etc. will occur. For the healthy growth of babies, babies in a period of rapid growth and development need to supplement enough vitamin D to prevent the occurrence of rickets. Therefore, when we usually say that babies need calcium supplementation, it is more accurate to say that vitamin D is supplemented to promote calcium absorption.

In addition to its role in calcium and phosphorus metabolism and bone calcification, it is also related to allergic diseases, infectious diseases, myocardial infarction, diabetes, metabolic nephropathy and many other diseases. With the development of the economy, the incidence of allergic diseases is increasing, seriously affecting children's health and daily life and study; in addition, children who are deficient in vitamin D are more likely to suffer from infectious diseases such as pneumonia and enteritis, which also cause serious impacts. Therefore, we say that the role of vitamin D is quite large.

What is a normal vitamin D level?

If you are concerned about vitamin D deficiency or vitamin D poisoning, we can draw blood to check the level of 25 (OH) D. 25 (OH) D is the most abundant, most stable, and longest half-life vitamin D metabolite in the human body. Its serum concentration level is the best indicator of vitamin D nutritional status. Its normal value is 20ng/L. <12ng/L can be diagnosed as deficiency, and the level in the middle is insufficient. When it is >100ng/L, it is excessive, and >150ng/L should be considered poisoning.

The drug instructions clearly state that overdose can lead to poisoning, which is a concern for many parents. If the baby only supplements according to the recommended preventive dose, that is, one per day, there is no need to worry about overdose or poisoning.

How to supplement vitamin D ?

1. Babies who are exclusively breastfed: According to the recommended guidelines of my country, babies under 1 year old should take 400 IU (1 piece) of vitamin D per day. Babies who are exclusively breastfed are recommended to take vitamin D supplements a few days after birth, with a total daily amount of 400 IU (1 piece). After adding complementary foods, unless the baby is fed with fish liver of deep-sea fish at a rate of more than 100g per day, there is no need to supplement. Otherwise, the vitamin D intake from food will not have much impact, and can continue to be supplemented at the preventive dose.

2. Babies fed with milk powder: within 1 year old, if the daily milk intake exceeds 1000ml (the amount of milk after mixing), there is no need to supplement vitamin D, because 1000ml of milk powder contains 400IU of vitamin D. If the child's daily milk powder intake is less than 1000ml, directly supplement 400IU.

3. Children over 1 year old: 600 IU (1 piece) per day for children over 1 year old, so you need to continue to supplement. Also, because many people nowadays do not spend enough time in the sun and often use proper sun protection when outdoors, foods rich in vitamin D are often excluded in order to reduce cholesterol intake, so vitamin D supplementation can be a lifelong process.