6. Dietary sources of vitamin D
While sunlight is the primary source of vitamin D, certain foods also contribute to daily intake. Natural dietary sources include fatty fish such as salmon, mackerel, and sardines, which contain vitamin D3 (cholecalciferol). Egg yolks and liver provide smaller amounts.
In some countries, foods like milk, orange juice, and cereals are fortified with vitamin D to help prevent deficiency. However, diet alone is often insufficient to maintain optimal levels, especially in populations with limited sun exposure.
- Fatty fish (salmon, mackerel, sardines)
- Egg yolks
- Liver
- Fortified dairy products and plant-based milk alternatives
- Fortified cereals and orange juice
7. Supplement forms
Vitamin D supplements are available in several forms, each with advantages depending on personal preference and absorption needs. Common forms include tablets, capsules, gummies, and oral sprays. Tablets and capsules are widely used and typically cost-effective.
Gummies offer a palatable option but often contain added sugars. Oral sprays can provide more rapid absorption and are convenient for individuals with swallowing difficulties. Vitamin D3 (cholecalciferol) is generally preferred over D2 (ergocalciferol) due to its greater potency and longer duration of action in the body.
8. Groups at risk of deficiency
Certain populations are more vulnerable to vitamin D deficiency and may require targeted screening and supplementation. These include:
- Older adults with reduced skin synthesis capacity
- Individuals with limited sun exposure, such as those who are homebound or wear covering clothing for cultural reasons
- People with darker skin tones, as higher melanin levels reduce vitamin D production in the skin
- Individuals with malabsorption disorders or chronic kidney disease
- Obese individuals, due to sequestration of vitamin D in adipose tissue
Recognizing these risk factors helps prioritize testing and preventive strategies.
