Of course, but the point is, reduce their intake by how much? And for how long? And does everyone function well long term in a calories deficit? Like I said be

Of course, but the point is, reduce their intake by how much? And for how long? And does everyone function well long term in a calories deficit? Like I said before, running a marathon is simple, just run and don't stop running until you finish it. So why don't more people run a marathon?