How do the statistics on human life expectancy in developed countries align with the fact that lifespans are in God’s hands, and does attention to health increase one's lifespan, while poverty and environmental degradation in developing countries shorten human life?

It must be believed that Allah ordained the destinies of creation and the lifespans of human beings before the creation of the heavens and the earth, and that these destinies do not change. However, Allah ordained these destinies with their associated causes. So, whoever takes the means for safety and is saved, that is written; and whoever abandons them and perishes, that too is written. Taking the means for safety can be a cause for a longer life if Allah so wills it, as can upholding kinship ties and fearing Allah. If the statistics are accurate, they are part of the pre-ordained destiny.