MY WORLD OF TRUTH

Saturday, 25 March 2017

Am I getting enough Vitamin D?

Are your ‘sunshine vitamin’ levels low? Discover why you need vitamin D, how to get more and what to do if you're concerned about your levels...

Why do we need Vitamin D?

Vitamin D is made in our skin via direct exposure to sunlight. Our liver and kidneys then convert it into a form we can use. Vitamin D is extremely important for strong bones and teeth, as it helps us absorb the calcium we eat and it also controls the amount of calcium in our blood. It’s really important that our vitamin D levels aren’t low or our body won’t absorb the calcium we eat.

There aren't any visual signs of vitamin D deficiency. If our levels are very low and we are severely deficient, we are at risk of developing weaker bones which is a condition known as osteomalacia. Severe deficiency in children may result in soft skull or leg bones and their legs may look curved or bow-legged, which is a condition called rickets. As low levels are common in the UK, it's worth getting tested if you're concerned. Ask your GP for a blood test.

**Vitamin D levels explained**
Vitamin D blood ranges	Classification
Under 25nmol/L	Deficient
25 - 50nmol/L	Insufficient
50-75nmol/L	Sufficient
Over 75nmol/L	Optimal

How much sun do we need?

It is difficult to give a one-size-fits-all recommendation for sunlight exposure during the summer months. This is because so many other factors affect the amount of vitamin D that's made in the skin, including your skin colour and age, the strength of the sun, the time of day and where you live. Guidelines regarding this are under review and more information is anticipated later in 2016. The recent SACN report suggests that everyone over the age of one needs to consume 10mcg of vitamin D daily in order to protect bone and muscle health. In addition, public health officials say that in the winter months people should consider getting this from vitamin D supplements, if their diet is unlikely to provide it. See the NHS website for current advice.

A word of caution though, too much sun exposure can be damaging due to the risk of developing skin cancer. Only spend a small amount of time in the sun without sunscreen either early in the morning or late in the afternoon and the rest of the time be sure to cover up and avoid any chance of sunburn.

**Amount of sun required to compensate for 49 days of no exposure**
Skin type	Minutes of July sun required
Fair	10 - 12 mins
Asian	30 mins
African/ Afro-Caribbean	120 mins

What affects our Vitamin D levels?

Several different factors can affect our vitamin D levels such as skin pigmentation, age, season, clothing and use of high factor sunscreens. As elderly people have thinner skin they are unable to make as much of the vitamin as younger people. Also, the position of the UK means that 90% of it lies above the latitude that permits exposure to the sun rays necessary for vitamin D synthesis. The southern part of the country is marginally better positioned for vitamin D synthesis (the closer you are to the equator the better). All of these factors will have an effect on our levels.

Approximately 60–70% of the UK adult population have insufficient levels of vitamin D in winter and spring and 16% are considered deficient. At present, there are recommendations for daily intakes for just a few specific groups, including 7mcg for babies from seven months to three years, and 10mcg for pregnant and breastfeeding women and over-65s. Whilst UK recommendations have not been set for the general population, some groups are considered to be at higher risk for developing deficiencies. These include:

Pregnant and breastfeeding women
People who have darker skin, such as those of South Asian, African or Afro-Caribbean descent
Men and women who are over 65 years of age
Babies and children aged six months to five years
Adults who stay out of the sun or cover up when outside

Vitamin D in our diet

Foods that naturally contain vitamin D include oily fish such asmackerel,sardines, tinned salmon, herringand kippers. Some foods are fortified with small amounts of vitamin D, including breakfast cereals, infant formula and margarine. There are smaller amounts found in eggs and some red meats, such as duck,goose, pheasant and venison however, the exact amount is unknown. Breast milk also contains vitamin D and mums should make sure they aren’t deficient as this will affect the levels in their milk.

**Vitamin D-rich foods**
Food per portion	Vitamin D content
Kipper (grilled, 140g)	14µg
Herring (grilled, 140g)	22.5µg
Mackerel (grilled, 140g)	11.9µg
Tinned salmon (140g)	19µg
Sardines (grilled, 140g)	7µg
Branflakes (fortified, 30g)	1.4µg
Hen eggs (poached, 2)	2.9µg