I don't think that there is a concrete answer to this. However, if we are to compare the life expectancy of people during the early times to the people of this modern world, I would say that this has significantly decreased. This can be explained by the factors that greatly affects our wellbeing such as our lifestyle and our environment.
Nowadays, people are not as physically active, as we tend to be engaged in activities that do not require us to even get up on our seats. We spend so much time on social media, on mindless internet browsing that we forgot how regular exercise and workout can totally impact our health. Our diet has also taken a major shift. We have been so inclined into eating fast foods because we claim that by doing so, we are saving much of our time, and that we can spend the time we saved in preparing and cooking food on other activities that we find interesting. We have also been engaged in various bad habits, which continuously degrade health such as smoking and drinking alcohol. All these lower our chance of living a longer life.
Moreover, so much pollution on the environment has caused the birth of several diseases that were not present in the early times. Various plague and epidemic has taken over several areas, and the worse case is that these strains of diseases eventually become resistant to the cure that humans have been developing. They, too, are evolving because we are providing them the conducive environment to do so. There are so much threats in the environment as there are humans on earth.
However, I do think that no matter how much we take care of ourselves, we still cannot predict how long we are going to live. Hence, let us just enjoy and appreciate every moment we have.