- UVB light during pregnancy produces vitamin D.
- Vitamin D may lower the risk of craniotabes by increasing calcium absorption and improving calcium metabolism.
Craniotabes is a softening of the skull bones in newborns. It generally lasts a few weeks or months.
Most infants with craniotabes are born to mothers with a low vitamin D level during pregnancy. Approximately one-third of newborns have this disorder. This coincides with that fact that one-third of the U.S. population has vitamin D blood levels below 20 ng/mL (50 nmol/L).
Sunlight exposure and craniotabes risk
Exposure to ultraviolet-B (UVB) light is the primary source of vitamin D for most people.
A study in Japan found a relationship between craniotabes and the season of birth:
- More craniotabes were noted in infants born in April and May. This is two months after the low wintertime vitamin D levels.
- The lowest number of craniotabes were noted in infants born in November. This is two months after high summertime vitamin D levels.
Vitamin D and craniotabes
Vitamin D levels
Several studies have found a relationship between vitamin D levels and craniotabes:
- In Finland, more infants born with craniotabes were born to mothers with lower vitamin D levels.
- In the United Kingdom, 10% of Asian infants born with very low vitamin D levels had craniotabes, although the presence of this condition was not reflected in bone mineral content compared to those without craniotabes.
- A study of three-month-old infants in South Africa found little correlation between craniotabes and rickets or other body parameters.
- Mongolia has a high rate of craniotabes and vitamin D deficiency.
- Craniotabes has been found in up to one-third of all newborn infants. Most likely, the mothers had low serum vitamin D levels.
How vitamin D works
Vitamin D may benefit craniotabes in two ways:
- Increase intestinal absorption of calcium from food and supplements
- Aid calcium metabolism and facilitate its incorporation into hard tissues (bones and teeth)
However, just how vitamin D regulates calcium metabolism is not fully understood. This area is still being studied.
Vitamin D and calcium
The best way to prevent craniotabes is to ensure high levels of vitamin D and adequate levels of calcium and protein during pregnancy.
Recent studies suggest that pregnant women need as much as 6000 international units (IU) (150 mcg)/day of vitamin D3 (cholecalciferol). This is the active form of vitamin D made in the skin. Vitamin D levels should be above 40 ng/mL (100 nmol/L). In the United States, two-thirds of the population has vitamin D levels below 30 ng/mL (75 nmol/L).
Craniotabes is easily treated with vitamin D. One study suggests 5000 IU (125 mcg)/day for infants. But this may be a bit high. A safe dosage might be 2000 IU (50 mcg)/day. For many years, infants in Finland under the age of one year were given this dosage. Sometimes megadoses of vitamin D are injected into the infant. It may be assumed that the necessary calcium will be obtained from mother’s milk or infant formula.
Find out more…
We will be adding a detailed evidence summary on this topic in the near future. Please check back soon to find out more.
Page last edited: 17 May 2011