Sunlight and Health Page Four

Safe sun bathing

Expose yourself to strong direct sun everyday when possible for at least 10 minutes provided you do not feel any unpleasant burning or baking sensation. The power of the sun varies greatly with the time of day, the time of year and the cloud cover. And so in cloudy weather or at off peak times a longer time, half an hour or even an hour or more, should be spent in the sun (in a bathing suit when possible) for optimum vitamin D synthesis in the skin. Avoiding the sun completely by covering up with clothes, covering up with suncream or always seeking the shade will cause vitamin D deficiency and risks serious disease.

The sun is strongest for two hours around solar midday (1pm in summer). People who have seldom or never sunbathed before should begin cautiously with just a few minutes exposure. Regular exposure will naturally lead to a tan which should not be a cause for any worry. A tan reduces the amount of sunlight penetrating the skin by about half and so a person who is tanned will be able to stay out safely in the sun for longer. People with a dark skin will need to stay in the sun for longer anyway - up to an hour or even more in full sun to get an optimum amount of vitamin D. But a dark or black skin can burn if it has not been regularly exposed to the sun in the past so care must be taken at first.

A person with a white skin will have made the maximum amount of vitamin D that can be made in one day after about 20 minutes in full sun. (This may take up to two hours or more for a person with a dark or black skin.) So after 20 minutes (or longer for darker skin) it is advisable to cover up, seek shade or use a high factor suncream - cover up earlier of course if the skin begins to get at all red or uncomfortable.

Pregnant women should sunbathe in this way at least three times a week if they can, but in the British climate it is only for a few weeks each year that there is clear sunshine enabling people to sunbathe at their convenience - so it is advisable to take a supplement too (see below). Babies can be safely taken into weak sunlight (avoiding 11am to 3pm) in only their nappies (no suncream) for between 5-10 minutes a day, according to Professor Nick Bishop of Sheffield University. A total of 30 mins. per week may be sufficient to give them adequate vitamin D. If the child is taken into the sun fully clothed without a hat or gloves then two hours per week is needed to obtain adequate vitamin D. A baby with dark skin will need longer in the sun.

Experts disagree about older children. Some suggest allowing children to run around freely in weak sunlight but put on suncream, full clothes and hat from 11 am, taking care to avoid full sun during the four hours round midday. Others believe that for optimum health children should be fully exposed in a swimsuit to full midsummer sunlight for some 15 - 30 minutes a day without any suncream, so long as they do not burn.

More.....Page FIVE