When your shadow is longer than your height you make no Vitamin D.
This is a statement from Dr Sue Lanham-New, advisor to the National Osteoporosis Society, who is a nutritionist specialising in the study of Vitamin D, speaking at a conference this week on Active Ageing that I attended. One aspect of her talk was on Vitamin D levels which she describes as impossible to sustain through sunshine and diet alone during the months October to March. Public Health England now recommends a supplement of 400 IU (international units), or 10 micrograms, per day for all people over the age of one during these months because the body cannot formulate enough Vitamin D for good health. A lack of Vitamin D can lead to conditions such as osteomalacia – a condition where bones soften and weaken leading to deformities of the bone. Vitamin D is needed to keep bones, teeth and muscles healthy. A combination of Vitamin D, calcium and weight bearing exercise maximises bone mass and protects the bones from resorption (breakdown). Sufficient calcium levels can be achieved through food.
The body’s inability to make Vitamin D begins to happen in September, but as the Vitamin D already formed in your body will last another month, then supplementation is recommended from October. During April to October Dr Lanham-New claims that we need 20 to 25 minutes exposure to the sun’s rays, which work even through cloud, on our face, neck, and lower arms between 10.30 a.m and 3 pm in order to produce enough Vitamin D.
The Vitamin D council website suggests that certain groups of people are more susceptible to a lack of Vitamin D: the elderly as they can have thinner skin, pregnant women, those who are overweight or obese, and people who spend most of their day indoors.
Dietary sources of Vitamin D include oily fish, (herring, mackerel, fresh tuna salmon and sardines), egg yolks, red meat, fortified breakfast cereals and liver. However, The Department of Health states
“since it’s difficult for people to get enough vitamin D from food alone, everyone (including pregnant and breastfeeding women) should consider taking a daily supplement containing 10mcg of vitamin D during the autumn and winter”
So, it’s time I bought my Vitamins again….