Oh, stop it. You're 35 years old. Lots of people don't work out. Donald Trump eats bad foods and doesn't work out, and he's just as much of an idiot now than he he was before. No worse! Go for walks, eat healthier, do some volunteer work, take up some hobbies that challenge you a little, travel, get a pet, in other words bring healthy changes into your life that make your brain work a little more. Even sleeping on the opposite side of your bed forces the brain to work. Learning a language forces the brain to work and develop new synapses. Your brain is okay and by the time you are in your 80s the treatments for dementia and Alzheimers will be much better than they are now.