Earlier when the medical system was not modernised a mother was giving birth to ten children in spite of that population was less in those days. That was because only a strong life will survive and the remaining will die. Those who survive have fought with the environment and winner of life they live longer and whatever life they have they would have least problems like BP, sugar, cancer, thyroid, heart attack, kidney etc.
Today mother gives birth to only one child and no matter what, whether that child is weak or strong, as per the nature, they want to make sure it must live. Thus we have so many weak people around. Interestingly some look strong but one emotional or physical blow of life can throw them to the earth.
After this for the whole life we spend money in hospital and ensure the weak must survive. Not only that we have laws and religion in support of the weak.