It depends! If you are just above the lower limit of normal and it is the start of the winter then I would be looking to optimise your level by taking a supplement as it is likely to drop further without strong sunlight exposure. If it is at the start of the summer months or you are expecting to go on a sunshine holiday and you will be spending lots of time outside then you will probably make enough vitamin D to optimise your levels. If for whatever reason you spend most of your time indoors or your skin is sensitive to the sun then you would be wise to continue a supplement of vitamin D all year round. Don’t forget that vitamin D is fat soluble and best taken with a meal containing some fat so it will be better absorbed.
What are the main symptoms of Vitamin D deficiency?
The common symptoms I find in general practice are musculoskeletal pains. But vitamin D is involved in so many other body processes, not just bone and muscle health. It has roles in the immune system, in blood sugar regulation, cancer prevention, it helps to reduce inflammation and is important in mental illness too. It is a factor in the development of osteoporosis and rickets in children if it is persistently very low.
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