Is This the Surprise Reason You're Always Tired?
How vitamin D can give you more energy and lower blood pressure
By Catherine Ostler
As a mother to three children under 12, I expect to feel totally exhausted at the end of the day. What I didn’t realise, though, was that a lack of an essential vitamin could be to blame for my paltry physical stamina.
A while ago, during a series of blood tests for some imaginary ailment (no doubt tiredness related), my levels of vitamin D – essential for the absorption of calcium – were found to be very low.
The doctor didn’t seem to think this was significant but, as my mother, aged 78, has osteoporosis, I thought perhaps I should take a supplement. The condition, where bones become brittle, has been linked to a lack of vitamin D, although there are strong genetic factors as well.
I’d probably have thought little more of it, but last month, I read about intriguing research which found boosting vitamin D intake can raise energy levels and lower blood pressure.
In the study, by a medical team in Edinburgh, volunteers were asked to cycle for 20 minutes. They were then given either a placebo or vitamin D and, two weeks later, were asked to cycle for 20 minutes again.
Those who’d taken the vitamin D were able to ‘cycle longer with less effort’ and showed diminished levels of the stress hormone cortisol, which can also cause raised blood pressure as it narrows blood vessels.
Vitamin D deficiency is a peculiarly contemporary phenomenon. The most efficient way of absorbing what is an essential vitamin is through sunlight directly on the skin.
But, ironically, in our bid to avoid sun damage – a contributory cause of both skin cancer and premature ageing – many of us just don’t get enough.
Indeed, some ten million people in the UK are estimated to have low levels of Vitamin D.
Though the Scottish study only had 13 participants, its lead author, Dr Emad Al-Dujaili, of Queen Margaret University, is convinced of its importance.
‘Vitamin D deficiency is a silent syndrome linked to insulin resistance, diabetes, rheumatoid arthritis, and a higher risk for certain cancers,’ he says...