The Prolongation of Life: Optimistic Studies

This book by Elie Metchnikoff, a prominent Russian scholar famous for his numerous achievements in biology and medicine, has achieved wide critical acclaim, both positive and negative, in its time. In this book, Metchnikoff concludes that a person's health largely depends on the health of their intestine. Furthermore, he studies the diets of many ancient people and finds out that each cuisine contains milk products like yogurt. Hence, he concludes that the consumption of such products is very important for human health.