Is vitamin D deficiency hereditary?

Vitamin D is a unique vitamin because your body is able to produce it in the skin through sunlight exposure, and provided sunlight exposure is sufficient, you can maintain adequate vitamin D levels in your body this way.

Vitamin D can also be obtained in small amounts through diet but not enough to meet all your vitamin D requirements.1 Maintaining adequate vitamin D levels, for most people, can be achieved from sun exposure experienced during regular daily activities and incidental exposure.2

Nevertheless, vitamin D deficiencies are a concern in Australia and factors that may increase a person’s risk of developing a deficiency include:3

  • Having very dark skin
  • Wearing concealing clothing for religious or cultural reasons
  • Taking certain medicines and some medical conditions

In addition to the above risk factors, researchers have identified four gene variants thought to play a role in vitamin D deficiency. These common gene variants, which include those involved with cholesterol, vitamin D metabolism and vitamin D transport, were found to be associated with vitamin D deficiency. The more of these variations an individual has, the greater their risk of developing the condition. Knowing who carries the gene variants could help doctors identify who is at risk and reduce the chance of low vitamin D before it develops or worsens.4

Vitamin D deficiency is also hereditary in the sense that it may also be passed on from mother to baby. If a mother has low vitamin D levels during pregnancy or when breastfeeding, then her baby is also at risk of lothrw vitamin D. This is because babies obtain their initial store of vitamin D from their mothers. Infant formulas are fortified with extra vitamin D, but breastmilk contains very little.

Breastfed babies are therefore more reliant on their mother’s stores than formula fed ones.3