At 50, if you are on a diet on your birthday, you can't eat a piece of your birthday cake. So grab two, a piece in each hand and, lo and behold, you will be on a balanced diet! Happy birthday, old chum!
Brain power improves by brain use, just as our bodily strength grows with exercise. And there is no doubt that a large proportion of the female population, from school days to late middle age, now have very complicated lives indeed.