The earth around Lake Naivasha, a shallow freshwater basin in south-central Kenya, does not seem to want to lie still. Ash from nearby Mount Longonot, which erupted as recently as the 1860s, remains in the ground. Obsidian caves and jagged stone towers preside over the steam that spurts out of fissures in the soil and…
It has started to get really wintry here in London over the last few days. The mornings are frosty, the wind is biting, and it’s already dark by the time I pick my kids up from school. The darkness in particular has got me thinking about vitamin D, a.k.a. the sunshine vitamin. At a checkup…