In this short-form video Dr. A explains the fundamental difference between digestion and absorption, outlining the mechanical and chemical steps that transform macronutrients into absorbable micronutrients. He describes how chewing, stomach mixing, and intestinal motility prepare food, while acids, enzymes, bile, and fluids chemically break down proteins, fats, and carbohydrates into amino acids, free fatty acids (via chylomicrons and the lymphatic system), and simple sugars that enter the bloodstream. The talk also covers micronutrients—vitamins and minerals—derived directly from food, and highlights the role of plant polyphenols and flavonoids (found in herbs, spices, and colorful plant parts) in modulating gut immunity, biofilm health, and inflammation. Dr. A ties these concepts to traditional indigenous diets, emphasizing that herbs and spices historically served preservation, taste, and health functions. Practical advice such as thorough chewing is offered, and the video concludes with a call to action for viewers to engage with future content.
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Hey, this is Dr. A. I am going to make good on a promise where when we talked about some of the issues around the orchestration of digestion and how complex it is to get food in you and get it all broken down the right way and all of that, and how that can lead to certain digestive and other imbalances in your body, I said we would separately deal with some of the more base mechanical things. So This particular session, I want to answer the question about what is the difference between digestion of food and then absorption of food, because they're related, obviously, but they're 2 different processes. So, as we talked about in that other video, digestion has a bunch of potential inputs and components. So, that includes things like mechanical activity. So, The movement of the stomach, I've talked about, it's like a sort of a cement mixer, and then the other different type of movement of the small intestine where you're squeezing down in 2 spots and then the place in the middle fills up with the digesting food so it can digest more but also absorb. Then there's chemical things. You have the acid, you have enzymes start in your mouth, you have acid, You have enzymes that come in later, you've got bile for breaking down fats, and then you have a lot of fluid that comes in through your mucous membranes, etc., which has a number of purposes. One is to help to liquefy the food as it digests, and the other is to help it actually— some of the transporters that take your Absorb nutrients and require some of those water molecules, etc. The other thing is, you know, there's mechanical things beyond the motion of the muscles in the digestive tract. There's chewing and swallowing, obviously, a number of other things. So that's why, you know, when your grandma told you that you need to chew your food well, that's actually a very good piece of advice. The better it gets chewed, before it leaves your mouth, because you can't chew it anywhere else, the easier it is for the stomach to do its thing, and so on and so on. So digestion is this mechanical process of breaking down the macronutrients. Now, macronutrients are basically what you would see on your plate. So there's going to be food on your plate, hopefully, and there's going to be a group of fats, a group of carbohydrates, A group of proteins, right? And then there's also probably going to be some polyphenols and flavonoids. Those might be in the shape of, you know, spices or certain parts of fruits and vegetables, etc. So there's other chemistry that goes on too. Macronutrients, big. So all the fat together, all the carbs together, all the protein together. Micronutrients are what you want to get out of the food that you eat, And so what happens is, when you go through this digestive process, the whole point of all of the digestive process is to keep breaking the food down to the point where the macronutrient, which say maybe would be a protein, has now been taken apart by the stomach acid and opened up, and then there's enzymes that go and open it up more and more and more, and it gets down to smaller chunks. So proteins break down into amino acids, And sometimes those are polypeptides, are still fairly long, but the ones that get absorbed mostly into your bloodstream are single amino acids and then di- and tripeptides, so 2- and 3-chunk things. And wonderfully, almost said magically, you could think of it magically if you want, but wonderfully, there are specific cells, the columnar cells in your digestive tract, that actually have enzymes inside of them. So if a 2- or 3-part amino gets in there, there are peptidases that will take them apart and put the amino acids in your blood. Well, why is that so important? Well, one thing is if you get too many big protein chunks into your blood, they can be antigenic and you can develop sensitivities or allergies or have bad reactions to them. But the other thing is the purpose to go from macronutrient to micronutrient is so that your body can use those amino acids, you know, to rebuild you or use them for DNA synthesis or whatever. So, So you want it to be ready to go. Kind of the same where the fats go in and they're broken down, they are liquefied in the stomach, and then the bile gets together with them and breaks them up into little packets, and then they're actually absorbed through the same cells but into a different system. They actually go in through your lymph system, the chylomicrons, and that go in through the little lacteals, little lymphatic vessels in your gut. And so fats go kind of through a different route. But the goal is to get them to be free fatty acids. The reason for that is that then is the easiest currency to use as a fat. You don't want, you know, giant long complex fats. If you need those, your liver usually will take care of making those for you. And then you have, of course, carbohydrates. Now, those turn into sugars, and kind of like the amino acids, there's a couple different types that can absorb. But there are special enzymes that once you break the carbohydrate down, so Let's say you ate a complex carbohydrate like broccoli. There's going to be a lot of it that's polyphenols that they're going to break off. There's going to be fiber that breaks off, and then there's going to be the digestible sugars, and they're going to get broken down, down, down to be smaller sugar components. And again, that goes in, and the parts that are sugars become your blood sugar. We had a previous talk about blood sugar, but that's where they come from. Now, as I mentioned, in addition, when you're eating food, to carbs, protein, and fat, you also are naturally consuming vitamins, hopefully, and minerals as part of the food. So another reason, you know, why certain types of foods, you know, you try and put them together is there will be higher vitamin mineral content, maybe different vitamin mineral content across different food types. So, for example, you may, if you eat meat, you might find you, and with the internet you can look all of this up and get way more information than we've ever had, you can just look at the nutritional value of the different types of meat you eat, what minerals are coming with it, what vitamins, what fats come in it, etc. If you're going to eat a lot of, you know, cabbage or you're going to eat a lot of broccoli you're going to eat apples or whatever, you can find out all that stuff that's in there. So vitamins and minerals also come from the food. They're not macronutrients like fat, carb, or protein, but they are a micronutrient that's very, very important. The other thing I mentioned all along was the colorful parts of plants, the polyphenols, the flavonoids, and as I said, those tend to come from 2 routes into your diet. One route is going to be herbs and spices. They're very, very dense in these sorts of things. We've had long, you know, the 1-hour-long YouTube videos that you see up there that I do. We've gone way into this and even some, you know, cooking for health ideas and stuff like that. But why are those so important? Well, the colorful parts of plants where most of your polyphenolic compounds and bioflavonoids come from are very immunomodulating. They help us blunt a lot of inflammatory effect in the body. They can help us to be resistant to bad bugs building up in our digestive tract, all kinds of things. And if you look back, just, you know, of anthropological interest, the things that we're all really hot on now in the polyphenol world as far as health goes, Every indigenous diet that I've ever looked at— I haven't looked at every one of them, but everyone I've ever looked at— if you go back to, you know, kind of the source people of an area, of many things— now, they may have had limitations in what they could eat because they were in the far north of Scandinavia or Siberia or someplace, or they were in the Mediterranean, or they were in very arid area or they're very coastal, so their macronutrients may have come from very different places. But one thing that is a thread that goes through all of the traditional indigenous diets is the use of whatever local plant additives they had to the food. So not just that they, you know, had, you know, a leafy vegetable or a fruit or something, But every indigenous diet also has polyphenolic compounds that they add to the food. Sometimes they were added for storage purposes and they just donated that and they didn't really know that's what was happening. Sometimes they were added for taste, as herbs and spices often are. So herbs and spices, you know, historically were either used for preservation, taste, or both. And it's really important to remember that. And so You know, I've had people ask me, well, you know, if digestive tract biofilms are a big deal, which they are, how do you prevent that? Well, largely, if they're not pathological and they're just sort of the normal ones, you maintain them in your body with these phenolic compounds that come from herbs and spices and things. So people eating, you know, kind of in the days before we knew a lot about food safety and all that, They learned it the hard way. These herbs, spices, and other phenolic compounds that they would use to store or make their food taste better actually kept them healthier. Well, that's the digesting versus absorbing as promised, and I'll probably cross-link both of those little things, but we're running out of time for a short-form video. So I'm Dr. A. Please like, share, subscribe, Hit the notification bell. I have as many questions as I have probably days to answer them, so there'll be a lot of these coming along. Thank you very much, and I really appreciate you guys listening.
