Epidemiological studies suggest that sunlight reduces all cause mortality, and particularly cardiovascular mortality.
The investigators have previously shown vasodilatation and a transient fall in blood pressure following irradiation of human volunteers with 2 standard erythemal doses of UVA radiation. This was independent of vitamin D and temperature rise and correlated with a nitric oxide synthase independent mobilisation of NO stores from the skin to the systemic circulation.
In this randomised, sham-controlled, cross-over double blind study, they will measure whether twice daily UVA administration can produce a sustained fall in BP and other cardiovascular risk factors in a cohort of pre-hypertensive patients.
