if there was good evidence one way or the other a study wouldn't be ethical. There isn't good evidence.
Who says that nut allergy rates have increased? Not the professor in Liverpool quoted earlier up the thread. Reported rates may have increased because of greater awareness. One study on the Isle of Wight showed an increase.
One large study has suggested government advice wasn't widely followed initially anyway - see below - although asking women years later if they ate nuts in pregnancy relies on their memory and we all know about pregnancy brain.
Where is the evidence that advice is contrary to what is known about how allergies develop? Very little is known!
What happens elsewhere needs to be interpreted with caution. The peanuts eaten in other countries are not generally treated in the same way as peanuts eaten here - and they are less allergenic.
No disresprect intended but the average GP knows nothing more about allergy than what he reads in the paper. People die in this country from nut allergy because they were given poor advice.
- The impact of government advice to pregnant mothers regarding peanut avoidance on the prevalence of peanut allergy in United Kingdom children at school entry. Hourihane JO, Aiken R, Briggs R, Gudgeon LA, Grimshaw KE, DunnGalvin A, Roberts SR.
Infection Inflammation and Repair, University of Southampton.