Walnut is not only the best brain food, but also a therapeutic agent for neurasthenia. The elderly have dizziness, insomnia, palpitation, forgetfulness, loss of appetite, weakness of waist and knees, general weakness, etc. Eating 1 ~ 2 walnuts every morning and evening can play a nourishing and therapeutic role. You can eat walnuts before going to bed. It should be noted that walnuts contain more fat. If you eat too much before bed, it will affect your sleep. It is best to eat only one walnut, or drink a bowl of paste made of walnut powder and black sesame powder.