Research has consistently shown that one of the most bio-available forms of vitamin D – the type synthesized in skin after exposure to sunlight, known as D3 – is not necessarily easy to get every day. For one thing, nearly every public health authority warn that ultraviolet rays can damage skin and increase the risk of skin disease. For another, the efficiency of D3 synthesis depends on skin shade, according to new research.

A study included in the journal Cancer Causes and Control found that pale-skinned people often have vitamin D insufficiencies, particularly when they live in high latitudes or work indoors.

The authors tested 1,200 participants for their levels of vitamin D, finding that many of the fairer volunteers had suboptimal amounts of the nutrient in their systems. Researchers recommended that pale-skinned individuals consider taking daily dietary supplements that contain vitamin D.

Lead author Julia Newton-Bishop, who hails from the UK’s University of Leeds, summed up the study succinctly.

“Fair-skinned individuals who burn easily are not able to make enough vitamin D from sunlight and so may need to take vitamin D supplements,” she wrote.