Sean Parker, Food Allergy Fighter

Sean Parker is terrified of peanuts. The former Facebook president and Napster co-founder has severe food allergies that have landed him in the emergency room more than a dozen times. Parker isn’t waiting for the pharmaceutical industry to hand him a cure. Last December he pledged $24 million to Stanford University to fund an eponymous center for allergy and asthma research. “I tend to invest or contribute in areas where I understand the topic well enough to call bulls---,” says the billionaire entrepreneur.

The center is headed by Dr. Kari Nadeau, a pioneer in the use of oral immunotherapy, in which patients consume tiny amounts of the foods they’re allergic to until their immune systems learn to tolerate the allergens. This method isn’t new—in early 20th century England, “doctors would say, ‘Let’s just vacuum the sofa, boil down the dust, and inject it into the patients,’ ” says Nadeau. Immunotherapy in the form of injections for pollen and cat dander has become mainstream, but researchers have been slow to try the treatment for food allergies, fearing fatal reactions from hypersensitive patients.