Dr. Kari Nadeau
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Can you picture a world without food allergies? There's a lot of work to be done, but I think we can get there with science and new ideas through research. I'm Kari Nadeau. I'm a mother of five. I'm an allergist, a pediatrician, an immunologist, a scientist and the director of the Sean N. Parker Center for Allergy & Asthma Research at Stanford University. For the past 25 years, I have seen the impact of food allergies in patients' lives. I am also witnessing the possibility of a world without food allergies, through science. Food allergies are rising. In this family that's multi-generational, there's a chance that one in four people will have a food allergy at some point in their lives. That's a 300% increase compared to 20 years ago. In fact, in the United States, two children out of every classroom have food allergies. It's not just a childhood disease though; it's also an adult disease. It's thought that 4% of all adults in the United States have food allergies. That's equivalent to a stadium of about 40,000 people, about 1,600 of them will have food allergies. That's a whole section of the stadium. Moreover, of children and adults with food allergy, 25% will have a severe allergic reaction at some point in their lives. And that's increased if someone has multiple food allergies. Dr Ruchi Gupta in Chicago has studied how much the cost is to the US healthcare system. It costs 25 billion dollars a year to take care of people with food allergy, because of emergency room visits, because of special diets, and because of days off from work. With that in mind, that's equivalent to 400,000 research grants to 400,000 researchers to be able to try to find the cause and the cure of food allergies. I'm sure all of you are aware of the restrictions, in schools as well as labeling laws, due to food allergies. Those are only going to increase because the rate of milk and peanut allergies, for example, is increasing and doubling every 10 years. For some tree nuts, it's tripling. Those statistics bother me. They motivate me. And importantly, patients' stories will ensure to inspire us. Years ago, I took care of a family with food allergies. The mother came to me with her identical twins. And the identical twins, they had similar allergies, to milk and cashew, but they also had different allergies: one to wheat and one to peanut. So the mother asked me to be able to think about diagnosing them through a good, gold-standard diagnostic technique, which is called a food challenge. She also told me that in her family, she did not have any allergies, but her husband had hay fever. So I explained that in a food challenge, we slowly, in a clinic, increase the dose and watch for an allergic reaction. And that allergic reaction can actually represent the immune system getting confused and thinking that the food is a danger signal. Just like we get a bee sting, and we have redness and hives and wheezing and a potential blood-pressure drop; the same can happen with food allergies. So her sons went through the food challenge, and they had a severe allergic reaction. And that was very unnerving, very anxiety provoking. And so the mother asked, "What can I do? What can I do to prevent this from happening again in my children? And importantly, why are food allergies rising in this world?" And so I explained that science has shown that it's a blend between genetics as well as environment and how that impacts the immune system. Importantly - as like this mom - no parent should have to live with the fear and the disabling feature of food allergy. No patient should have to live in fear of eating food at school, at home, in social situations. Because of this, I made it my work to be able to try to solve the food-allergy problem. Fortunately, many people are looking at prevention. There is a pathway, thanks to science, to be able to think about that possibility. The power of prevention can begin at home. There are many scientists looking at the potential causes of food allergy to be able to think about ways to prevent them. And there's not just one cause. It's what we call multifactorial. In fact, it's probably due in a large part to our changes in our modern life. Compared to years ago, we don't live as much on the farms. We don't get exposed to animals. We don't have a diverse diet for our infants as much anymore. And we don't spend as much time outdoors. Because of that, we are now looking at ways to understand the factors that can be decreasing our risk for food allergies. My colleague Dr Katie Allen in Australia studies this in 15,000 families because the rate in Australia of food allergy is one in eight children. She has now found, as well as Dr Carlos Camargo in Boston and Dr Corinne Keet in Johns Hopkins University, that there are six "D's," and there are probably more, but I'll talk about them now. We think that being around in dirt is helpful; we think that taking care of dry skin with good creams and good emollients is going to help decrease your risk of food allergies; as well as diversifying your diet early and often in infancy. Healthy levels of vitamin D. Perhaps getting a dog early in life as well as using less detergents for infants. We think all will decrease the food-allergy risk. That's encouraging news. Science performed by Dr Donald Leung in Denver, Helen Brough in the United Kingdom, Julie Parsonnet and Scott Boyd at Stanford, and through a consortia at the National Institutes of Health have all designed ways to test how these factors are associated with each other. Importantly, if you have dry skin or eczema - that can crack the skin. And in infants, if they have tiny amounts of food allergen exposed to their skin over time, the immune system gets confused again. It thinks that's a danger signal, and the person can start having a food allergy. But that's counterbalanced with the GI tract. If you actually eat the food orally, that can train your immune system to protect against that danger signal. And so at the age of about four to six months, when you're introducing solids to your baby, many scientists have found that a diverse diet can help reduce the risk of food allergies. Dr Gideon Lack, for example, went to Israel and realized that the children that were eating Bamba actually had a lesser rate of food allergies. And so he designed a study in hundreds of infants to be able to introduce a diverse diet. He specifically also looked at introducing peanuts, and what he showed was that the rate of peanut allergy in those children that were exposed to peanut early through their diet had a fivefold decreased risk for food allergy. And he found it to be safe. That's a radical idea. And compared to when I was raising my children, in the year 2000s, I was being told to avoid, avoid, avoid, delay the introduction of milk and peanuts and shellfish until they're at three years of age. Now we've turned a 180, and in fact, it's the exact opposite - that we actually want to diversify that diet. The National Institutes of Health has come out with guidelines now to be able to help us introduce peanut to infants to be able to try to reduce the risk of peanut allergy. That's a radical new idea. That's revolutionary. But it's disruptive, and it could make us feel uncomfortable. However, it could benefit us greatly. So let me give you the recipe for being able to try to prevent food allergies. Diversify the diet, take care of dry skin with cream and emollients, roll around in the dirt, get healthy amounts of vitamin D, and perhaps that will decrease the risk of food allergy. No family should live with the burden of restrictions and food allergy. What I've told you today does not just stay in the lab and the clinic. You can do this at home. Let's go back to the family with twins. When the mother wanted to have a third child, she came to my clinic with the baby, and she said, "What can I do to prevent food allergies in their sister?" And she went home, talked to me, bought a dog, (Laughter) took care of the baby's dry skin very well with creams and emollients, introduced a diverse set of foods between the ages of four and six months, when the child was eating solids. And that child is now five years old and does not have food allergies. And you can do this too. You can now be part of science and research to be able to try to prevent food allergies through new ways and new ideas. Thank you. (Applause)