Human physiology has been molded over the millennia by famine. From these origins, human biochemistry and metabolism are therefore ill-equipped to handle the modern environment. Dr. Andrew Prentice explores the thrifty gene hypothesis against the backdrop of evolutionary pressures, exploring the relationship of the nutritional environment to ovulatory fertility. There is strong evidence linking body composition and adiposity to fertility and birth rate. Environmental factors such as seasonal fluctuations in food supply have lasting effects not only on birth rates, but on infant birth weight. Through the mechanisms of epigenetics, the nutritional environment can thus modulate the health of future generations. Prentice reviews key data from developing countries such as Gambia and places these findings within the context of the global nutrition transition. Although these findings support the importance of early life programming, Prentice reveals that we must consider an integrated life course approach when designing nutritional interventions.