Leading article: Here comes the sun

The sun will have his hat on again this weekend. And science suggests we should make the most of it. A new study has shown that spending just 20 minutes basking in the sun can be a good defence against getting a cold or flu in the winter months.

It's apparently thanks to vitamin D, which is produced by our skin when it comes into contact with sunlight. A healthy supply of vitamin D boosts our immune systems, which is the reason colds and flu are significantly less common in the summer months when sunlight is plentiful.

Most of us do not get enough sunlight. We work indoors, travel in cars, lather on sun cream when we do venture out. Of course, too much sun is a very bad idea and enhances the risk of skin cancer. But as this study suggests, we do need a little more light in our lives.

So for at least a little while this weekend, become a sun-worshipper.