VITAMIN D FOR WINTER IMMUNITY
What can you do to support your body’s winter immunity against colds and ‘flu’?
Winter is here and the peak season for colds and ‘flu is fast approaching.
Recent research (1) shows that vitamin D enhances the immune system's ability to fight the winter viruses and bacteria implicated in respiratory infections. It is estimated that 1 in 5 adults in the UK have low levels of vitamin D. So, maintaining optimum levels of vitamin D can help protect against colds and ‘flu.
Why is Vitamin D important?
Technically a hormone, vitamin D plays an important role in many functions in the body. As well as immune system health, Vitamin D aids calcium and phosphorous absorption which is essential for healthy bones, teeth and muscles. It is also associated with cardiovascular health, cell differentiation and brain function.
Where does the body get Vitamin D?
Our main source of this important nutrient is through our skin’s exposure to the sun’s UVB rays. But in the northern latitudes of the UK, especially between October - March, the sun’s rays are too weak for us to produce vitamin D. The stores we build up through sun exposure from during the summer months rarely last through the long winter.
It is found only in a small number of foods. Oily fish such as mackerel, sardines and salmon provide the richest source. To get a daily dose of 10 micrograms (mcg) you’d need to eat 1-2 portions of salmon. Small amounts are found in egg yolks, meat, liver, milk and mushrooms. Other sources are fortified foods such as breakfast cereals and fat spreads. It might be difficult to get enough from foods that naturally contain vitamin D and/or fortified foods alone.
Your optimum level of Vitamin D
The amounts of Vitamin D a person needs can vary. For example, those with darker skin, the elderly, people who spend long hours working indoors, those who use sunscreen or avoid the sun due to sun sensitivity, those with a diet poor in Vitamin D, on certain medications and with certain health conditions are all more likely to have lower levels of Vitamin D. These people would all benefit from supplements of Vitamin D not just through the winter but all year round.
New UK government guidelines based on the 2016 report by the Scientific Advisory Committee on Nutrition (SACN) (2) now recommend that all adults and children (5 and over) should supplement with 10 mc
g of Vitamin D through autumn and winter months to ensure adequate levels.
As with other nutrients high levels may be as problematic as low levels. Too much vitamin D can lead to hypercalcaemia (high blood calcium) and is associated with kidney stones and low bone density so it’s important to supplement at the correct dosage to meet your individual needs. High doses may however be used short term to address a deficiency.
Vitamin D Testing
Vitamin D testing can be useful to check that levels are within optimal range.
The Vitamin D test is now available at Therap-Ease Health and Wellness Clinic in Morningside, Edinburgh.
Cost £28 and results within a week.
Our experienced Nutritional Therapist, Pauline, is available to offer advice based on your individual needs and results. Call 0131 447 9990 to book.
1 Vitamin D supplementation to prevent acute respiratory infections: systematic review and meta-analysis of individual participant data’. Martineau et al. BMJ 2017. doi: 10.1136/bmj.i6583.