Hello
Nutmeg and fig are good for health in any case but unfortunately they are not particularly known for helping with anxiety.
There are things however that should not be consumed are chocolates, Chinese (with ajinomoto), cold drinks, and tea/coffee as they contain caffeine which are known to increase anxiety. Red meat including dishes should also be avoided.
He could also be encouraged to join some sport. There are some simple breathing excercises like anulom-vilom which helps in curbing anxiety.
Next Steps
if issues still persists, consult a therapist