Dr. Will Bulsiewicz: Most People Get This Wrong: Food Allergy vs Food Intolerance | Be Well Moments

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0:10I'm sure you talk about this and see this a lot in patients that come to you, but it's food intolerances, which is different to a food allergy. And a food allergy is more severe and it happens very, very quickly, but a lot of people can suffer with food intolerances. How can we identify them?

0:26Dr. Will Bulsiewicz:So I think that you appropriately started with the first question, which is, is it a food allergy or a food intolerance? We have to make that distinction. It's an important distinction. A food allergy, allergy in general, means that your immune system is being activated in response to something that is foreign to your body. So that could be seasonal allergies or exposure to pet dander, or in this case, it's exposure to a specific food. Now, there are these classic foods that are known to trigger food allergies, and we think that they account for over 90 % of food allergies out there. And this includes fish, shellfish, eggs, dairy, wheat or gluten-containing products, soy, corn.

1:11Dr. Will Bulsiewicz:I may have forgot one, but I think that covers either all of them or very close. Sesame was recently added to the list as well. I commend you for just remembering one of those. But the key here, though, is that when you consume this food in any amount, it could be the smallest amount. It could be the tip of the tongue touching a little bit. It will activate your immune system and initiate a violent reaction. And that reaction can manifest with digestive symptoms, but typically will also manifest with systemic symptoms, meaning throughout your entire body, which could be hives, skin changes, swelling.

1:48Dr. Will Bulsiewicz:The stuff that we get scared of as doctors is if you get swelling of the lips or of the throat because that could negatively affect your ability to breathe. Do you want to know what mine is, Will? Yeah. It's the worst allergy of all time. It's grapefruit. Grapefruit? Do you get it? Is it an oral allergy? Yeah. My tongue explodes. I get lumps and welts all over my body. Like, I restrict some breathing. Other citrus you do okay? Yeah, citrus is fine. But I'm just giving the love out there. It's grapefruit. to anyone else that's got that allergy. I feel you. Wow. Wow. Yes. Okay. I think that the key here is that you've just exemplified though because if you touch, if you put grapefruit to your lips on any level, you don't even have to like literally put a piece into your mouth.

2:34Dr. Will Bulsiewicz:You can literally just put your lips on the grapefruit. It would probably trigger that reaction and that's a scary reaction. That happened last week. I put in a cocktail, just a tiny little bit and I barely touched it. And my night was over within minutes. So that's an allergy. Yeah, that's an allergy. And that's the activation of the immune system. And a food intolerance is different. So we have to rule out food allergy first. And then what is left is a food intolerance is when you consume a food in normal amounts. Like, you know, if we drink a gallon of milk, we're going to get sick. We're all going to get sick if we drink a gallon of milk, right?

3:15Dr. Will Bulsiewicz:But that's not a normal amount. A food intolerance is when you consume a food in normal amounts and it triggers symptoms. And the reason why is because this is not activation of your immune system in response to a foreign thing. This is your body struggling to process and digest the food. And so it's sloppy digestion. The classic food intolerance is lactose intolerance. If we expand our view, there's sort of two main categories of food intolerances that I think about. These are the classics, and they're unique and different. The first is in response to carbohydrates. These are FODMAPs. So F-O-D-M-A-P.

4:00Dr. Will Bulsiewicz:This is an acronym that stands for fermentable oligosaccharides, disaccharides, monosaccharides, and polyols. It's a mouthful. I'm so pleased you said that, not me. Yeah. It includes fructose, which is a sugar that you will find in many fruits. It includes lactose from dairy products, fructans, which are more complicated, almost like fiber, and you will find them in garlic, onions, in gluten-containing foods, so like wheat, barley, and rye. So in a number of different foods, you can find these fructans. And then galactans, which you'll find in legumes. And finally, the polyols are the sugar alcohols that you may find in fruit, but you may also find in artificial sweeteners that you add to your coffee or something like that or your tea.

4:55Dr. Will Bulsiewicz:This group, this big group of FODMAPs, this is one type of food intolerance. And it's interesting because there are these people who think that they have gluten intolerance. And we could dig into the evidence if you want to, Sarah, but many of these people, if they don't have celiac disease, actually, they're not responding to the gluten. They're responding to the fructan, which is found in the wheat or the barley or the rye. And so food intolerance. Or the other type of food intolerance is histamine intolerance, which is not quite as common as FODMAP intolerance. But histamine intolerance is basically where you have a damaged gut.

5:34Dr. Will Bulsiewicz:And because you have a damaged gut, your body is struggling to process and digest high histamine foods. And this could include like the classic high histamine foods are like fish, shellfish, fermented foods. And then among the plant-based foods, spinach, tomatoes, avocados, and eggplant. Those are the classic high histamine foods. The key with these is that your body can be trained to consume these foods. And if you were to take these foods that you have an intolerance to and reduce and moderate the amount that you consume at one time, you'll be fine. So if you simply reduce the amount, you can consume these foods that you struggle with.

6:22Dr. Will Bulsiewicz:And by reducing that amount, you actually start to get better at consuming these foods. And so it's conceptually similar to exercise. No one walks into the gym on the first day and lifts the heaviest weights. The people who are lifting heavy weights, it's because they've been building up to that for many years. Each of us has a certain capacity for work that we're capable of. and so when we go to the gym you should work out within the the bounds of what your body is capable of doing without crossing that line and when you do this the line starts to move and over time you're able to do more and that's the concept of exercise and that's the same concept that we should apply to overcoming food intolerances exercise your gut and you will make it stronger one billion people worldwide are deficient in this nutrient that so many of you guys might not be aware of and women if you're listening you are more risk of being deficient in this nutrient so i'm going to first of all explain what the physical symptoms are if you have cold hands and feet pale skin extreme lack of energy or fatigue then you might be suffering with iron deficiency or anemia now first off please go to your gp to get your iron levels checked.

7:38Secondly, please explore a good iron supplement. Many people that come to me are worried about taking iron supplementation because it can cause constipation or GI distress. That's why I'm so incredibly proud to be partnering for this episode with Spartone, the number one iron-rich water supplement. Now, I've personally been using these for years. The reason why is because they are naturally sourced, highly absorbable iron. That means it's much more gentle on your stomach. There's no harsh tablets. It's just one naturally sourced ingredient that works very well. You can pick it up in boots or buy online at Amazon, but please do not ignore this.

8:21It is really critical to make sure your iron levels are in check. I love that you conceptualize this into two different parts. And I think a lot of people may have heard and, or definitely our listeners would have heard the FODMAPs in relation to obviously Monash University and we had actually then come on and talk about how they created the FODMAP diet and heavily linked to IBS and and that was you know fascinating and obviously as you said it's it's not something that you can never have the whole part of the FODMAP diet is that it's meant to be a short-term strategy and then you're meant to reintroduce these foods whereas sadly when it's done incorrectly a lot of people get like an incredible amount of fear from these foods because they're terrified of reintroducing them and that's when you know actually a lot of kind of disordered eating can happen.

9:04But then you also mentioned another one, which is a chapter in your book, by the way, it's a whole chapter on histamine. It's fascinating because my brother, actually, the other day, doesn't really have any food allergies, any intolerances. And I'm sure he won't remember saying this. It was about six months ago, and his whole body just all of a sudden reacted. I mean, his tongue was slulled up. And I mean, when you were talking about like an allergy, this was the response. And we were trying to figure out what it was. and when he went to A &E the doctor said what have you eaten and he was like what I eat every day salmon beans like normal things but he'd left the salmon in the fridge for so long typical man hadn't like put it in any protective packaging and the histamine had risen so high that it caused a really big kind of histamine reaction can you talk a little bit more about how can we detect like which route are we going down so if someone's listening to this and saying okay well I've got a food allergy and I don't really know where to start, maybe I have a histamine allergy, or maybe I go down kind of the FODMAP side.

10:05How can people navigate this area a lot more and a lot more clearly?

10:10Dr. Will Bulsiewicz:Great question. Your brother, what he had specifically, we call scombroid poisoning. And it's not necessarily indicative of a chronic histamine intolerance. So the reason why I'm bringing it up is there's a bit of a distinction. To me, a chronic histamine intolerance is that when you routinely consume foods that are higher in histamine, you manifest symptoms. Whereas in his case, it was a one-time deal where he consumed this bad fish. And it's a classic thing. And it's the bad fish, because it basically hasn't been cooked and it's been sitting out for too long, has turned into a super high histamine food.

10:51Dr. Will Bulsiewicz:And even with a healthy person, it would overwhelm them and they get this form of food poisoning. All right, how do we approach this issue? So let's pretend for a moment, if it's okay, I would like to break this into three possibilities. The three possibilities are a food allergy, FODMAP intolerance, or histamine intolerance. Okay. Now, food allergy is going to be a manifestation of systemic effects. It could be gas and bloating. It could also be skin changes, swelling, things like this, lightheadedness, all right, to one specific food or to one class of foods, right? So it could be dairy products.

11:38Dr. Will Bulsiewicz:And every single dairy product food, if you consume it, you get this reaction, right? With you, the one food is grapefruit, right? It's no other food. It's just grapefruit. And the thing about a food allergy is that it's a response of your immune system to one of the proteins. It's always a protein. So if you have a food allergy, it's going to always, it's going to be consistent. It can be any amount, it could be small or large, and it's going to be these systemic effects. All right. Number two, in terms of possibilities, is a FODMAP intolerance. Now, a FODMAP intolerance is going to be to these classes of foods.

12:24Dr. Will Bulsiewicz:So it could be fructose or lactose, which is in dairy products, or fructans, again, in wheat, barley, rye, garlic, onions, or galactans from legumes. And it's not as necessarily consistent as the food allergy would be. It also is going to manifest with digestive-specific symptoms when it's a FODMAP issue, right? So it's like these are people that get gas, bloating, discomfort, diarrhea, or constipation, classically occurring in people that have irritable bowel syndrome or some other digestive health problem like ulcerative colitis or Crohn's disease, all right? So these are the people that will manifest one of these types of intolerances.

13:10Dr. Will Bulsiewicz:And again, like if you thought of these as categories, now this typically involves working with a registered dietitian. But if you were to work with a registered dietitian and basically test within these categories, you would find that it's not just grapefruit. It's this class of fructose containing foods that's causing the issues. So any food that contains fructose can be potentially problematic. All right. So it's a class effect and you're not going to get the tongue swelling or the hives or things like this. All right. The third one, less common, a little bit more tricky, is the histamine intolerance.

13:53Dr. Will Bulsiewicz:Because the histamine intolerance, yes, it will manifest with digestive symptoms like bloating. That's sort of the classic symptom. But most of the time with histamine intolerance, it's also going to manifest with other symptoms throughout your entire body. Could be headache. Could be migraine. A low histamine diet has been shown in clinical trials to be beneficial to people that have migraine headaches. This is like the origin of this concept. Thanks so much for listening. To hear the full episode, there's a link in the description. For more information,

14:36visit www.fema.govmit .org