Figure 1. The vitamin D hypothesis of ageing.

It is proposed that vitamin D acts to regulate ageing by controlling the activity of a number of the ageing processes. Vitamin D promotes the activity of autophagy, which acts to slow down the ageing processes by removing dysfunctional mitochondria. Vitamin D also acts to reduce mitochondrial dysfunction, oxidative stress, inflammation, calcium signalling, epigenetics and DNA disorders including telomere shortening, which act to drive the processes of ageing.