There is a hypothesis in the anthropological literature (e.g. Milton, 2003) that our complex human brains would not have developed without hominoids having routine access to foods of animal origin. In many countries, therefore, the consumption of animal source foods, and meat in particular, became part of a cultural identity, while in others (e.g. India) vegetarianism has long been part of the cultural/religious identity (approx. 30% of Indians are vegetarian, although the majority of those consume milk products). In the twenty first
century, humans can, theoretically, have access to non-animal-derived sources of nutrients required for brain
development, so animal products are no longer as important for nutrition as they were for our ancestors. There are also other issues, however, associated with livestock production which impact on the consumption of animal products. Culture in many countries has evolved to give a higher priority to the welfare of farm animals and there are additional ethical issues associated with the negative environmental impacts of livestock production. We read a lot, therefore, about the rise of veganism, with calls for diets free of animal products, yet there is also evidence that the consumption of meat at a country level increases as the income of that country increases (FAO, 2009). The average global per capita meat consumption at over 40 kg, has,
therefore, doubled from the consumption in 1960. However, the annual global rate of increase in both meat and milk consumption is projected (OECD/FAO, 2017) to decrease slightly in the decade from 2017-2026, to 1.5% per annum for meat and 1.9% per annum for milk.