Breed info says they are prone to allergies but I have never seen anywhere that they all have allergies so I can't really give you a good answer on that. I'd say with the food thing (allergies aside) it's just in general bulldogs are sensitive and high maintainence, they should always be fed a high quality food to maintain good health. Well I believe that should be the case with any breed but other dogs can live their whole lives on purina and be fine I just wouldn't personally want that for any dog I had because they are like children to me and good nutrition is definitely something I would want for them. Samson's allergies definitely get worse during certain times of the year like the fall. Symptoms for Samson's allergies didn't start to appear until he was just under a year. I can't really think of anyway to prevent them but good food and just taking care of their general health. Hope that helps!