WEBVTT 1 00:00:00.000 --> 00:00:06.920 Welcome back. I'm Chandler. In this lesson, we're going to take a deep dive in understanding how 2 00:00:06.920 --> 00:00:13.320 our digestive system works. Our digestive system is responsible for breaking down our food, 3 00:00:13.320 --> 00:00:19.920 absorbing it, and helping to disseminate those nutrients throughout the body. My goal is that 4 00:00:19.920 --> 00:00:24.680 by the end of this lesson, you'll not only understand how the digestive system works, 5 00:00:24.680 --> 00:00:30.360 but have a basic understanding that if we work to support it and work with it, 6 00:00:30.360 --> 00:00:36.000 we can give our bodies what it needs to complete its many functions. To start, 7 00:00:36.000 --> 00:00:42.200 we know that we have a digestive system. Our digestive system is comprised of many organs 8 00:00:42.200 --> 00:00:48.560 working together to break down, digest, and assimilate the nutrients in our food to fuel 9 00:00:48.560 --> 00:00:54.440 everything in our body. Food digestion starts in our mouth through chewing and the secretion 10 00:00:54.440 --> 00:01:00.280 of saliva that begins to break down our food. Food then travels down our esophagus to our 11 00:01:00.280 --> 00:01:05.800 stomach where digestion continues through stomach acid and the churning motion of our stomach. If 12 00:01:05.800 --> 00:01:11.840 you don't have enough stomach acid, you can't digest food properly or absorb its nutrients. 13 00:01:11.840 --> 00:01:18.320 This can lead to indigestion, malnutrition, and sometimes even bacterial overgrowth. Your 14 00:01:18.320 --> 00:01:24.360 stomach will hold the food until it's ready to go into the small intestine. Our small intestine is 15 00:01:24.360 --> 00:01:30.880 where the bulk of our digestion and assimilation of our nutrients occur. As food enters the small 16 00:01:30.880 --> 00:01:37.160 intestine, it mixes with digestive juices from your liver and your pancreas. Your intestinal 17 00:01:37.160 --> 00:01:43.600 wall absorbs nutrients and the water from food and then sends waste products to the large intestine. 18 00:01:43.600 --> 00:01:51.240 So let's take a closer look at the accessory organs to our digestive system now. So as food 19 00:01:51.240 --> 00:01:57.760 enters the small intestine, like I said, the food is going to mix with digestive juices that help to 20 00:01:57.760 --> 00:02:03.840 further break down and digest what is consumed. Your liver works around the clock to keep you 21 00:02:03.840 --> 00:02:12.240 healthy. It has many roles, not only in digestion, but in detoxification for the body as well. Among 22 00:02:12.240 --> 00:02:18.560 its many roles, it produces bile, which is stored in the gallbladder. This is a chemical that helps 23 00:02:18.560 --> 00:02:26.200 turn fats into energy that your body uses. Bile is necessary for the digestive process. The liver 24 00:02:26.200 --> 00:02:32.720 helps your body maintain a healthy level of blood sugar. Your liver supplies glucose, otherwise known 25 00:02:32.720 --> 00:02:39.000 as sugar, to your blood when it's needed. It also removes glucose from your blood when there's too 26 00:02:39.000 --> 00:02:45.800 much. In addition to aiding in digestion, your liver does a few other things that I believe are 27 00:02:45.800 --> 00:02:52.120 really important to note. First, your liver creates albumin. This is a blood protein that 28 00:02:52.120 --> 00:02:58.640 helps carry hormones, drugs, and fatty acids throughout your body. Next, your liver helps 29 00:02:58.640 --> 00:03:04.640 your body get rid of bilirubin. Bilirubin is created through the breakdown of your red blood 30 00:03:04.640 --> 00:03:11.240 cells. Too much bilirubin in the body can cause jaundice. This is when somebody might have the 31 00:03:11.240 --> 00:03:18.440 yellowing of the skin and the eyes. Next, your liver is responsible for filtering toxins. When 32 00:03:18.440 --> 00:03:24.480 you take in a potentially toxic substance like alcohol or medicine, for example, your liver 33 00:03:24.480 --> 00:03:31.280 helps alter it and remove it from the body. Lastly, your liver controls immune response. So 34 00:03:31.280 --> 00:03:38.200 when bacteria, viruses, and other harmful organisms enter your body, your liver can find and destroy 35 00:03:38.200 --> 00:03:45.760 them. This is done by specialized cells in your liver. Next, we have your pancreas. Your pancreas 36 00:03:45.760 --> 00:03:51.800 is another accessory organ to digestion that I want to make sure to highlight. It is located 37 00:03:51.800 --> 00:03:58.240 inside your abdomen, just behind your stomach, and is about the size of your hand. During digestion, 38 00:03:58.240 --> 00:04:05.920 your pancreas makes pancreatic juices called enzymes. These enzymes help to break down sugars, 39 00:04:06.080 --> 00:04:12.560 fats, and starches. Your pancreas also helps your digestive system by making hormones, 40 00:04:12.560 --> 00:04:19.480 which regulate your blood sugar, regulate your appetite, stimulate stomach acids, and tell your 41 00:04:19.480 --> 00:04:25.720 stomach when they need to empty. The pancreatic enzymes that are secreted are three things. First, 42 00:04:25.720 --> 00:04:32.200 we have lipase. This enzyme works together with bile, which your liver produces to break down 43 00:04:32.240 --> 00:04:38.560 fat in your diet. If you don't have enough lipase, your body will have trouble absorbing fat and the 44 00:04:38.560 --> 00:04:45.720 important fat-soluble vitamins, vitamins A, D, E, and K. Protease is your next enzyme. This 45 00:04:45.720 --> 00:04:52.240 enzyme breaks down proteins in your diet. It also helps protect from germs that may be living in 46 00:04:52.240 --> 00:04:59.160 your intestines, like certain bacteria and yeast. Undigested proteins can cause allergic reactions 47 00:04:59.160 --> 00:05:00.360 in some individuals. 48 00:05:00.000 --> 00:05:07.080 Lastly, you're going to have amylase. This enzyme help breaks down starches into sugar, 49 00:05:07.080 --> 00:05:11.560 which your body can then use for energy. If you don't have enough amylase, 50 00:05:11.560 --> 00:05:15.120 you may get things like diarrhea from undigested carbohydrates. 51 00:05:15.120 --> 00:05:20.960 In addition to making enzymes that are released into your digestive system to aid in the digestion 52 00:05:20.960 --> 00:05:27.480 of food, your pancreas releases hormones into the blood that carry messages to other parts 53 00:05:27.480 --> 00:05:34.360 of your body and parts of your digestive system. These pancreatic hormones include insulin. 54 00:05:34.360 --> 00:05:40.360 Insulin is the hormone that helps your body use sugars for energy. Without enough insulin, 55 00:05:40.360 --> 00:05:44.560 your sugar levels rise in your blood and you can develop things like diabetes. 56 00:05:44.560 --> 00:05:48.960 Glucagon is the next thing. If your blood sugar gets too low, 57 00:05:48.960 --> 00:05:54.440 glucagon helps raise it by sending a message to your liver to release stored sugar. 58 00:05:54.440 --> 00:06:01.480 Lastly, you have gastrin and amylin. Gastrin is primarily made in the G cells in the stomach, 59 00:06:01.480 --> 00:06:06.880 but some is made in the pancreas too. It stimulates your stomach to make gastric acid. 60 00:06:06.880 --> 00:06:12.360 Amylin is made in the beta cells and helps control appetite and stomach emptying. 61 00:06:12.360 --> 00:06:17.920 Now that you have a basic understanding of what the accessory organs do to our 62 00:06:17.920 --> 00:06:23.280 digestive system, let's look inside our small intestine to understand what is going on. 63 00:06:23.280 --> 00:06:29.360 Once food passes into the small intestine, organisms that live in the GI tract help to 64 00:06:29.360 --> 00:06:35.400 digest our food further. Our intestine is structured as follows. Our intestinal lining 65 00:06:35.400 --> 00:06:42.240 has folds called villi that have deep crypts between them. These villi are lined with cells 66 00:06:42.240 --> 00:06:49.040 called enterocytes that are responsible for digesting and absorbing nutrients from your 67 00:06:49.040 --> 00:06:54.360 food. These enterocyte cells need to be young and healthy to do their job. 68 00:06:54.360 --> 00:07:01.160 If you look in the middle image, you can see what a fold in the intestinal lining looks like. 69 00:07:01.160 --> 00:07:07.240 To the right of that, you can see that the villi have these deep crypts within them. 70 00:07:07.240 --> 00:07:13.800 And to the very right, you can see an enterocyte that lines the villi. The way it works is that 71 00:07:13.800 --> 00:07:19.720 the youngest enterocytes are at the base of the villi, and as they age, they travel to the top 72 00:07:19.720 --> 00:07:24.640 where they eventually die off and fall off, and the process will continue over again. 73 00:07:24.640 --> 00:07:31.240 On the surface of the enterocytes and the villi, you have a layer of beneficial bacteria living 74 00:07:31.240 --> 00:07:36.320 right on top, which you can see on the image to the left. When everything is in balance, 75 00:07:36.320 --> 00:07:42.240 this bacteria not only helps keep the opportunistic or bad bacteria in check, 76 00:07:42.360 --> 00:07:49.640 but the bacteria also provides 60-70% of the energy needed to the gut lining. 77 00:07:49.640 --> 00:07:55.400 When this microbiome is disrupted and bacteria is not in the proper balance, 78 00:07:55.400 --> 00:08:02.160 then the bad bacteria can overgrow and things can happen like leaky gut or increased intestinal 79 00:08:02.160 --> 00:08:07.600 permeability, which is a condition that creates gaps in the linings of the intestinal walls. 80 00:08:07.960 --> 00:08:13.160 These gaps then allow things like food particles, bacteria, and waste products 81 00:08:13.160 --> 00:08:18.520 to seep directly into your bloodstream. Think of it like this. With a bacterial 82 00:08:18.520 --> 00:08:24.520 layer over our cells and villi, which you can see on the left, there is a thick layer of turf 83 00:08:24.520 --> 00:08:29.800 on the surface of the gut, which provides a protective layer against potential invaders 84 00:08:29.800 --> 00:08:36.080 like bacteria, yeast, parasites, and viruses. What you see on the right is an image of what 85 00:08:36.159 --> 00:08:41.400 happens when we have increased intestinal permeability, otherwise known as leaky gut. 86 00:08:41.400 --> 00:08:47.960 You can see in this image that the bad bacteria are at a higher percentage than the good bacteria, 87 00:08:47.960 --> 00:08:54.280 which slowly degrades the gut lining, allowing for increased permeability and for things like 88 00:08:54.280 --> 00:09:01.240 undigested food, viruses, toxins, and other things to leak straight through and go into 89 00:09:01.240 --> 00:09:05.560 your bloodstream, which can then lead to disease and other issues around the body. 90 00:09:05.560 --> 00:09:11.600 So now that I have explained that there needs to be a good balance between good and bad bacteria 91 00:09:11.600 --> 00:09:17.360 in the gut, I want to explain a little further what type of bacteria we have in our gut and 92 00:09:17.360 --> 00:09:22.800 the role of that bacteria. There are actually three types of bacteria that you can find in 93 00:09:22.800 --> 00:09:29.840 your gut. First is your essential flora. These we need in large, large quantities to keep everything 94 00:09:29.880 --> 00:09:33.640 else in check. So you want to think of these kind of like your little soldiers in your gut. 95 00:09:33.640 --> 00:09:42.080 Next we have opportunistic flora. Opportunistic flora is found in our gut and when kept in check, 96 00:09:42.080 --> 00:09:48.200 doesn't cause any issues. However, when there is an overgrowth of this type of bacteria, 97 00:09:48.200 --> 00:09:53.840 they can wreak havoc on our overall gut health and our immune system. Lastly, 98 00:09:53.840 --> 00:09:59.400 we have transitional flora. These are gram negative bacilli that are actually found in 99 00:10:00.000 --> 00:10:02.680 and when our gut ecosystem is in check, 100 00:10:02.680 --> 00:10:04.820 no issues will arise. 101 00:10:04.820 --> 00:10:07.040 I wanna highlight what our beneficial 102 00:10:07.040 --> 00:10:10.040 or essential flora actually does for the body. 103 00:10:10.040 --> 00:10:12.640 This flora is considered beneficial 104 00:10:12.640 --> 00:10:16.060 because it keeps the pH of the gut to four to five, 105 00:10:16.060 --> 00:10:19.200 making it a very uncomfortable living environment 106 00:10:19.200 --> 00:10:21.720 for the bad bacteria. 107 00:10:21.720 --> 00:10:25.400 This bacteria actually works synergistically 108 00:10:25.400 --> 00:10:28.600 with our bodies to help digest the food we eat, 109 00:10:28.720 --> 00:10:32.680 and then it actually helps deliver 60 to 70% 110 00:10:32.680 --> 00:10:36.040 of the energy we need to our gut lining. 111 00:10:36.040 --> 00:10:39.040 So now that we have looked at what our gut does, 112 00:10:39.040 --> 00:10:42.160 I want us to take a look at some examples 113 00:10:42.160 --> 00:10:46.680 of digestion occurring in a correct way in a healthy gut. 114 00:10:46.680 --> 00:10:50.060 Let's look at the digestion of milk and wheat proteins, 115 00:10:50.060 --> 00:10:54.080 since these are two very common offenders for people today. 116 00:10:54.080 --> 00:10:57.040 The digestion of milk and wheat happen actually 117 00:10:57.040 --> 00:10:58.400 in two stages. 118 00:10:58.400 --> 00:11:00.800 The first stage occurs in the stomach, 119 00:11:00.800 --> 00:11:05.340 where the stomach juices split the proteins into peptides. 120 00:11:05.340 --> 00:11:08.060 Different peptides can have different structures 121 00:11:08.060 --> 00:11:09.980 actually when they're broken down. 122 00:11:09.980 --> 00:11:12.560 Some of these peptides can actually have things 123 00:11:12.560 --> 00:11:15.520 like morphine-like structures to them. 124 00:11:15.520 --> 00:11:19.440 These peptides then move to the second stage of digestion, 125 00:11:19.440 --> 00:11:21.800 which occurs in our small intestine, 126 00:11:21.800 --> 00:11:24.860 where they mix with pancreatic juices secreted 127 00:11:24.860 --> 00:11:27.420 from the pancreas into the small intestine 128 00:11:27.420 --> 00:11:30.740 and work to break down them even further. 129 00:11:30.740 --> 00:11:33.300 When they reach the intestinal wall, 130 00:11:33.300 --> 00:11:36.860 they're broken down by enzymes called peptidases 131 00:11:36.860 --> 00:11:39.820 on the microvilli of your enterocytes. 132 00:11:39.820 --> 00:11:42.500 So in a normal healthy person, 133 00:11:42.500 --> 00:11:45.180 this can all occur without any hiccups. 134 00:11:45.180 --> 00:11:48.680 When people have gut dysbiosis or leaky gut, 135 00:11:48.680 --> 00:11:52.140 or a decreased ability to secrete stomach acid, 136 00:11:52.140 --> 00:11:54.940 pancreatic juices, or they don't even have 137 00:11:54.940 --> 00:11:59.220 enough good bacteria in their gut to help this digestion, 138 00:11:59.220 --> 00:12:02.100 these morphine-like peptides are absorbed 139 00:12:02.100 --> 00:12:03.740 straight into the bloodstream 140 00:12:03.740 --> 00:12:06.460 because of those gaps in the gut lining. 141 00:12:06.460 --> 00:12:09.020 This can then interfere with brain function 142 00:12:09.020 --> 00:12:12.100 and the overall immune function of your body. 143 00:12:12.100 --> 00:12:15.380 So as you can see, when our gut microbiome 144 00:12:15.380 --> 00:12:18.220 isn't functioning correctly due to leaky gut 145 00:12:18.220 --> 00:12:22.260 and improper balance of good and bad gut bacteria, 146 00:12:22.260 --> 00:12:24.940 food isn't gonna properly be digested 147 00:12:24.940 --> 00:12:26.940 and can cause things like allergies 148 00:12:26.940 --> 00:12:28.460 and even lead to disease. 149 00:12:28.460 --> 00:12:30.860 So to wrap up, I wanna quickly look at 150 00:12:30.860 --> 00:12:33.180 how this all plays a role in the immune system. 151 00:12:33.180 --> 00:12:36.380 Our lymphatic system, which is part of our immune system, 152 00:12:36.380 --> 00:12:38.580 is located all throughout the body, 153 00:12:38.580 --> 00:12:41.420 including in our intestinal wall. 154 00:12:41.420 --> 00:12:43.900 This lymphatic tissue in our gut 155 00:12:43.900 --> 00:12:45.760 has a large amount of lymphocytes, 156 00:12:45.760 --> 00:12:48.240 which produce immunoglobulins, 157 00:12:48.240 --> 00:12:52.280 one of the biggest ones being something called IgA. 158 00:12:52.280 --> 00:12:55.760 IgA's main job is to protect the mucous membranes 159 00:12:55.760 --> 00:13:00.760 from invaders like bacteria, viruses, fungi, and parasites. 160 00:13:01.160 --> 00:13:04.720 Science has actually shown us that in an unhealthy gut, 161 00:13:04.720 --> 00:13:06.840 these cells are compromised, 162 00:13:06.840 --> 00:13:09.960 which decreases our defense against bacteria, 163 00:13:09.960 --> 00:13:12.840 viruses, fungi, and parasites. 164 00:13:12.840 --> 00:13:17.480 Neutrophils and macrophages are the cells 165 00:13:17.480 --> 00:13:20.640 that gather in infected and inflamed tissues 166 00:13:20.640 --> 00:13:23.920 to work to clean them and rid them of any bacteria 167 00:13:23.920 --> 00:13:28.080 or toxins that are causing infection or inflammation. 168 00:13:28.080 --> 00:13:32.200 In an unhealthy gut, these cells can't function properly. 169 00:13:32.200 --> 00:13:34.900 A healthy gut also plays a huge role 170 00:13:34.900 --> 00:13:38.280 in the production of interferons, cytokines, 171 00:13:38.280 --> 00:13:41.200 and other regulators of the immune system 172 00:13:41.200 --> 00:13:44.280 that are responsible for fighting off viruses. 173 00:13:44.280 --> 00:13:46.960 So in simple terms, what does this mean? 174 00:13:46.960 --> 00:13:50.120 In a healthy gut, we can fight off against invaders 175 00:13:50.120 --> 00:13:52.560 through the cells listed on the screen. 176 00:13:52.560 --> 00:13:56.120 When our gut is compromised, so is our immune system, 177 00:13:56.120 --> 00:13:58.920 leaving us at risk for a whole slew of problems 178 00:13:58.920 --> 00:14:02.280 like viruses, autoimmune disorders, cancers, 179 00:14:02.280 --> 00:14:04.240 among many other things. 180 00:14:04.240 --> 00:14:07.440 So in closing, we can see how important it is 181 00:14:07.440 --> 00:14:10.080 for our gut to be functioning properly. 182 00:14:10.080 --> 00:14:13.480 When we don't have a healthy functioning digestive system 183 00:14:13.480 --> 00:14:16.760 and all of our accessory organs aren't doing their part, 184 00:14:16.760 --> 00:14:19.200 it can lead to illness and disease. 185 00:14:19.200 --> 00:14:21.860 In the next lesson, I wanna take a deep dive 186 00:14:21.860 --> 00:14:24.300 into metabolism and thyroid health 187 00:14:24.300 --> 00:14:27.500 to help us complete the picture of how the body works 188 00:14:27.500 --> 00:14:30.400 so we can have a foundational understanding of health. 189 00:14:30.400 --> 00:14:33.820 This will allow us then to appropriately understand 190 00:14:33.820 --> 00:14:38.040 how to apply the six pillars of health for optimal wellness. 191 00:14:38.040 --> 00:14:40.240 So I will see you in the next lesson.