I would've done from 6 months, but HV said since he has eczema and possibly asthma and reacts to dairy, he's probably more allergy prone so to leave shellfish and peanuts until 1 year. So he started having both recently, and likes them. He had peanut butter on oatcakes for supper this evening.
Thing is people can have an anaphylactic reaction to anything, not just peanuts. Strawberries, dairy, anything. I'm not sure if peanuts etc are more common as an allergy, more common as a serious allergy, or just more publicised.