The sleep industry is worth billions. They get everyone paranoid that if they don't get 7-9 hours there is going to be all these disastrous effects and our health. So many studies, back up their claims, but more often than not they are funded by the industry. If you go to a sleep clinic, they are going to set a goal for you to help get you to that 7 hours, they get a lot of business from people who are freaking out because they are not there. I only sleep 4-5 hours a night, and in the past I had a lot of anxiety about my health and or future health. I did the sleep clinic thing, no matter how hard I tried, even the CBT, I couldn't get up to that 7 hours. I tried sleeping pills, helps some, THC helped put me to sleep, but the quality wasn't very good and THC doesn't work for my life anymore. Finally, I met with a specialist who had a private practice, my goodness the degrees on his wall was impressive. Anyway, He told me the whole 7 hour thing is BS. He said everyone is different and some people only actually need very few hours and that is in their genetic code. Our species would not have survived if it were not for people that didn't need much sleep.
Back before humans had fire or light, clans could be not be out walking around at night, it was dangerous to do so. You step into a hole and break a leg, you are literally fked and probably going to die. So the group had a stay huddled up and still while it was dark. Some of the clan had to stay up and be alert for predators. Those people in the modern world that do not sleep much probably have that gene ADRB1 for low amount of sleep needed to feel fully rested. Former British Prime Minister Margaret Thatcher had that gene. She only slept 4 hours a night. My mom was a low hour sleeper, as was my grandfather. So, I no longer freak out about only sleeping 4 to five hours a night, I feel great anyway. It is the anxiety associated with not sleeping the recommended hours that is worse for you than the low amount of sleep. Finally there is a book called Set it and Forget it, I highly recommend it.