Africa Case

Health was better in many ways. European influence led to increased travel for people in Africa and introduced diseases from outside of Africa (e.g. Cholera, bubonic plague) to the continent. This spread disease and exposed people to diseases for which they had no resistance.

Also, Africans began growing "cash crops" to sell to the Europeans instead of growing crops to feed themselves. This led to their growing a single crop, so their diets became less varied, leading to greater malnutrition. Before that, Africans had reasonably decent diets that included a variety of vegetables, grains, and protein sources.

Before European intervention, Africans lived in small tribal communities, so infectuous disease was less of an issue because it was difficult for an infectuous agent to spread beyond a tribe, thereby limiting the number of people who could be affected by an infectuous disease. The Europeans brought cities and other population centers, where there were not only a high concentration of people to be infected, but there was also a high turnover of people bringing in new diseases from wherever they lived before.

Health for most Africans was arguably better in 1700 than it is there today or than it was under European colonization.

...