If a person has a peanut allergy, then they're more prone to having an allergy to beans, peas, lentils, senna and licorice.. andi know if you're allergic to soy you have a higher chance of reacting to things like green peas, chick peas, lima beans, string beans, wheat flour, rye flour, and barley flour. Also the protein in fava beans is highly allergenic in susceptible people.

 

There is no reason to assume you would develop an allergy to beans by just eating them. The lady in the other forum had a rare situation. She may have had the allergy before becoming vegan, and not know it because she did not eat enough to react or a number of other possibilities. I developed an allergy to corn, and my allergist can only speculate why. She does think it was from a combination of over exposure and a predisposition, since my mom is also allergic, but that would be hard to prove definitively.
Many allergist encourage rotating and diversifying your diet, which should actually make your body stronger. Beans are really great as a source of nutrition; give them a try.