Also, in agricultural settlements people lived packed together in larger groups, and among domesticated animals, setting the stage for unsanitary conditions that often led to disease. Eventually, as human agricultural societies became better organized and sanitation improved, the trend reversed. Human height rose on average, and people began living longer and enjoying overall better health. More recently, over the past 75 years, industrialized food systems have improved health and nutrition in the developing world. But we modern humans are still dealing with some of the same problems as our prehistoric agricultural ancestors. We tend to rely too much on corn, rice, and wheat for the bulk of our calories. And it's widely believed that the types of foods we eat, combined with our largely sedentary lifestyles contribute to obesity, diabetes, and other health problems.