Over the past few days it has been in the news that public health officials are urgently reviewing the potential ability of Vitamin D to reduce the risk of coronavirus and the risk of dying from it.
What is Vitamin D?
Many people are aware that Vitamin D is implicated in bone health. Recent research also suggests that it may have other benefits too such as protecting against colds and fighting depression. Some people know that you can “get it from sunshine”. A few people know what food it is found in: oily fish, eggs and liver. Overall, we simply aren’t getting enough Vitamin D:
- Rickets, a disease that we thought had vanished is re-emerging. A survey of paediatricians in 2006 found incidence of rickets in 8 children per 100,000
- At the other end of the spectrum, with an ageing population, osteoporosis is on the rise. The National Osteoporosis Society estimates that 50% of women and 20% of men over 50 will suffer some kind of bone fracture due to poor bone health.
- 90% of hip fractures in the elderly are caused by falls; a Cochrane review in 2010 found a 28% reduction in falls where Vitamin D supplements were used.
It’s true – the UK is having a quiet Vitamin D crisis.
How much Vitamin D should you have?
In July 2016 Public Health England recommended that children and adults over the age of one should have 10 micrograms (mcg) of Vitamin D every day. Reality of Vitamin D intake is very different. The most recent issue of the UK’s Diet and Nutrition Survey (May 2014) shows that in reality the intake for children 4-10 years is 1.9mcg daily and the over 65’s 3.3mcg daily.
We are equipped to manufacture Vitamin D, where a biochemical reaction in our skins converts cholesterol into Vitamin D. The reaction will only take place when the sun is at a sufficient angle in the sky to provide light within a specific UV bandwidth. In the UK the sun reaches this intensity for six months of the year from April to September.
Unfortunately the public health messages of the last few decades, warning of skin damage and cancer from exposure to too much sun. This – along with our changing lifestyles – means that we simply don’t get enough sun exposure to stimulate the amount of Vitamin D that we need.
Vitamin D Supplements:
Vitamin D in supplements can be expressed as international units (IU) where 40 IU is equal to 1 mcg. Therefore 10 mcg is 400 IU. If you are an adult do not take more than 100mcg of Vitamin D daily as this could be harmful. Check with you GP if you are under 10 years or taking medication as this may need to be less.
- If you make the decision to supplement your Vitamin D then buy from a good quality provider – I would suggest finding an independent health food shop or speaking with a nutritionist.
- All pregnant and breastfeeding women should take a daily supplement containing 10 micrograms of Vitamin D, to ensure the mother’s requirements for vitamin D are met and to build adequate foetal stores for early infancy.
- It is difficult to get enough Vitamin D from food alone. In spring and summer we may get enough from sunlight on our skin and a healthy balanced diet, but the rest of the year we may need supplements.
- Consider taking a daily supplement containing 10 mcg of Vitamin D, particularly during autumn and winter.
- Take a supplement year round if your skin has little or no exposure to sun due to being in doors or covering your skin, have dark skin or are elderly.
- Children aged 1-4 are recommended to have a daily 10 mcg Vitamin D supplement all year round.
Vitamin D and Sunlight:
Most people can make enough Vitamin D from being out in the sun daily for short periods with their forearms, hands or lower legs uncovered and without sunscreen from late March or early April to the end of September, especially from 11am to 3pm.
Research to date shows that moderate but frequent sun exposure is healthy but overexposure and intense exposure can increase your risk of skin cancer. The more skin you expose (without sunscreen) the more Vitamin D is produced. However – only expose your skin for around half the time it takes for you skin to turn pink and begin to burn. This will depend on the time of day, year, part of the world and your skin type.
Also, Your body can’t make Vitamin D if you are sitting indoors by a sunny window because ultraviolet B (UVB) rays (the ones your body needs to make Vitamin D) can’t get through the glass
Foods With Vitamin D:
- Fatty fish: Can be a good source of Vitamin D – such as salmon, trout, mackerel, tuna and eel. Wild-caught fish (425 IU in 3oz salmon, 547 IU in 3oz mackerel) Don’t forget the canned versions! Canned fish (154 IU in 3oz tuna, 270 IU in 3.5oz sardines)
- Certain Mushrooms: These can also produce Vitamin D when exposed to ultraviolet light – but you will need to check as most are grown in the dark. Check your supermarkets
- Fortified food: Lots of cereals are now fortified with various nutrients including Vitamin D. Be careful however, as cereals usually contain lots of sugar which is not a good thing to be eating. Some supermarkets are fortifying bread, milk and yoghurts (Marks & Spencer).
- Eggs: Vitamin D is contained in the egg yolk and each one will give you about 40 IU.
- Beef liver: Cooked beef liver is a brilliant source of nutrition to include Vitamin B12 and Vitamin D.
- Cod liver oil: One tablespoon contains about 1,300 IU’s of Vitamin D. Make sure that you get one from a reputable company
For further information, please visit the NHS’s Vitamin D guidelines. (Please note this has yet to be updated from 2016.)
This article is written by Karen Robinson, our Clinical Director.