During chilly mornings and evenings in northern Namibia's rainy season, the women of Okapembambu village draw steaming buckets of milk from their cows, despite the distraction of ankle-deep mud and manure. (From the book What I Eat: Around the World in 80 Diets.) Milk and its by-products are the Himba's most important source of nutrition. The women add a bit of soured milk to the fresh liquid to hasten the process of natural fermentation, and they shake calabash gourds for hours to make butter. They drink some of the soured milk, use some to make their cornmeal porridge, and mix butterfat with ochre to make their body cream.