If you live in the UK, there's a good chance your vitamin D levels drop in winter. Here's why — and what to do about it.
Why UK winters are a problem
Vitamin D is made in your skin when sunlight hits it. But from October to March, the sun in the UK isn't strong enough for this to happen. The angle of the sun means most of the UVB radiation that triggers vitamin D production is absorbed by the atmosphere.
What the NHS advises
The NHS and the Scientific Advisory Committee on Nutrition (SACN) recommend that everyone in the UK aged 4 and above should consider taking a daily supplement containing 10µg (400 IU) of vitamin D during autumn and winter. Some groups — including people with darker skin, those who cover up outdoors, and people in institutions — should supplement year-round.
Why it matters
Vitamin D contributes to the normal function of the immune system, the maintenance of normal bones and teeth, and normal muscle function. Severe deficiency can lead to rickets in children and osteomalacia (softening of the bones) in adults.
How much should you take?
The NHS recommends 10µg (400 IU) per day as a maintenance dose for most adults. Our Vitamin D3 + K2 provides 100µg (4,000 IU), which is a higher-strength product for adults who know they want more than the maintenance dose. Do not exceed the upper safe limit of 100µg (4,000 IU) per day from all sources without medical supervision.
D3 vs D2
There are two forms of vitamin D in supplements: D2 (ergocalciferol) and D3 (cholecalciferol). Our D3 is from lichen, a non-animal source, so it's suitable for vegans.
Food supplements should not replace a varied, balanced diet and a healthy lifestyle. This guide is general information, not medical advice. If you are pregnant, breastfeeding, take medicine or have a health condition, speak to your GP or pharmacist before taking a supplement.
Sources
- 1.NHS. Vitamin D. nhs.uk/conditions/vitamins-and-minerals/vitamin-d.
- 2.SACN. Vitamin D and Health Report. GOV.UK, 2016.
- 3.Public Health England. PHE publishes new advice on vitamin D. GOV.UK.
