Transcription
There are people with perfect immune systems, and yet their bodies destroy themselves from within. And it's not due to a lack of defenses, it's not due to viruses, and it's not due to genetics; it's because no one taught them to protect themselves from themselves. In 1983, doctors discovered something disturbing. Children born with brilliant immune systems, but without the ability to protect themselves, ended up with their bodies attacking all their organs at once. They died quickly, not from weakness. They died from an excess of strength. Currently, millions of adults make the same mistake, and no one, or very few, have likely received an explanation as to why. Today, we are going to talk about the great forgotten of biology, the system that decides when to stop. We are going to talk about the great error we made in understanding the immune system, because we believed the problem was that we had an uncontrolled army, and it turns out that what was missing was identifying the sheriff. And when there is no sheriff, even energy becomes dangerous. Well, we are also going to awaken the sheriff. In the previous video, we shed light on our cathedral. I explained how without voltage, without those millivolts of health, nothing works. But now, think that it's possible for your cathedral, that is, your own body, to be illuminated, but for there to be an army of brave soldiers inside, armed to the teeth, who suddenly go crazy. And it can still be worse. Imagine that those soldiers have the mission to protect you from dragons, viruses, and invaders, bacteria. But suddenly, imagine that they start shooting at the walls of your own cathedral, they start destroying the furniture, burning the curtains, and attacking everyone they find inside. Well, this is what science calls autoimmunity. It's friendly fire, meaning your body, which is wise, for some reason forgets who the enemy is. And for years, medicine called this a system error, and today, however, we know it's not an error at all; it's an absence of command when it happens. Well, today I am going to try to explain to you why this chaos occurs, and above all, I am going to introduce you, so you can get to know him, to the most important character in your defense system, the immune sheriff. If you have hypothyroidism, if your joints hurt for no clear reason, if your skin becomes inflamed, or if you simply feel that your body is at war with itself, stay, because today we are going to learn to activate what is the absolute master brake of your biology.
To understand the sheriff, we must first know the soldiers. And in your blood live some warriors called T lymphocytes. And they are called T because they train in an organ located right behind the sternum, an organ called the thymus. The thymus was an ignored organ for many decades, and until the 1960s, many doctors thought it served no purpose. Well, today, however, we know that without it, there is no biological identity. See how important it is. Well, these are the two types of soldiers I was telling you about: TCD4 lymphocytes, who are the generals, meaning they give the orders, detect the enemy, and shout "attack." And then there are the T. CD8 lymphocytes, who are the warriors, and these are the ones who execute, who have the chemical weapons to destroy infected or cancerous cells. And these soldiers have sensors on their surface called T-cell receptors, or TCR for short. And their job is to go through the body and recognize protein fragments. If the fragment is from a virus, shoot. And if the fragment is from your own body, they should ignore it. And now you'll ask me, how do they know if it's mine or foreign? Well, this is thanks to a process called thymic selection. In the thymus, the soldiers are presented with a veritable photo album of all the proteins in your body. And if a soldier tries to attack one of those photos, the body eliminates it before it enters the bloodstream. It's an absolutely brutal quality control. And now pay attention, because 95% of the soldiers, 95%, die in training because they are too aggressive. And then something else happens: sometimes some defective soldiers escape, go out to patrol, and suddenly mistake a protein from your thyroid or your collagen for an enemy. And there, my friend, the disaster begins. This process is so brutal that when it was discovered, many scientists simply didn't believe it. A system that eliminates 95% of its own cells just to avoid chaos. You see, a young Australian immunologist, Jack Miller, in 1961, while working in London, was the first to demonstrate that the thymus was not a useless organ, but a truly ruthless military academy. What did he do? He removed the thymus from newborn mice, and the result was brutal. The mice couldn't defend themselves, but more importantly, he discovered something even more disturbing. They didn't know how to distinguish between self and foreign. And what was the conclusion? The thymus was not a useless organ; quite the contrary. The thymus is the place in the body where the immunological identity of your body is educated. And this broke a centuries-old dogma. From then on, several groups, especially at the North American NIH, at the Pasteur Institute in France, and also in some laboratories in Germany, began to study what happened inside the thymus, and what they discovered was difficult to accept. When T lymphocytes train, I've already told you that more than 90% or even 95% die. And they don't die because they are sick or because they fail; they die because they are too dangerous. And this process they called negative selection or clonal deletion. Well, let's think for a moment, let's transport ourselves to the scientists, to the time of the scientists in the 1970s. They had deeply ingrained the idea that biology is wise, efficient, and economical, that it seeks to optimize resources and doesn't waste energy. And yet, here they had before them a system that does, or did, or continues to do, just the opposite. It deliberately eliminates the vast majority of its own cells, and it was real. In fact, not only was it real, it still is. Well, already in the 1980s, Filipa Marak and John Kepler confirmed something even more disturbing: that the body deliberately eliminates the vast majority of its own soldiers. It was confirmed. There were doubts for a long time; they didn't want to accept it. These demonstrated, without a doubt, that lymphocytes that recognize self-proteins are actively eliminated from the thymus. And it's not an accident, as I told you, nor is it a secondary consequence, much less an error. It's a decision of the system. The body prefers to destroy 95% of its army rather than risk facing a civil war. That is, it does it to protect itself. Biology has always understood something that we often forget: it's better to lose strength than to lose control. But don't be surprised, because we don't live in a body that sometimes fails. We live in a body that has built extreme systems to avoid chaos. And when that chaos appears, it's not due to weakness; it's because the brakes have failed, not the soldiers.
At this point, I will take a brief pause. I have presented many concepts that may be new to you: thymus, CD4, CD8 lymphocytes, cell receptors. The truth is, you don't need to remember them, much less memorize them. There is only one thing here that is necessary: that you understand that this entire system exists with a single objective: that your body does not confuse the enemy. And this is where our protagonist appears. Amidst this entire aggressive army, there is a special peace brigade: regulatory T cells, or simply Tregs. Tregs were not discovered yesterday; in fact, they were intuited in the 1970s, but no one paid attention to them. And you'll ask me, why? Very simply, because they didn't attack, and for decades, science only studied what destroys. In the 1970s, several immunologists began to observe something strange, and in experiments with mice, they saw that even when the immune system was perfectly trained in the thymus, something else had to be acting in the periphery. Why? Because some animals did not develop autoimmunity, even though in theory they had potentially dangerous lymphocytes circulating. That is, the thymus performed brutal selection, but it wasn't the only filter. And it was then that an almost heretical idea for the time emerged. Someone said, "There must be some type of cell whose function is not to attack, but to brake." And in a very vague way, they called them suppressor cells or suppressor cells. And that's where the problem began. These scientists were not listened to. At that time, as I told you, immunology was obsessed with killing bacteria, destroying viruses, understanding cancer, and studying inflammation. And their logic was absolutely military: the immune system is like an army, and in an army, the heroes are those who shoot, not those who say "stop." And what happened? It was more than evident that these supposed suppressor cells didn't kill, didn't inflame, and didn't produce antibodies. In fact, they were even boring from an experimental point of view. And furthermore, to make matters a little worse, the results were inconsistent; that is, there were no clear markers, they couldn't be distinguished well, and more than anything, they seemed like experimental noise, those things that happen around but don't give you confidence that they are interesting. And for almost 20 years, the concept remained shelved. Meanwhile, what happened in the thymus was being better understood, and it was already known that the thymus massively eliminates dangerous cells, but it was also intuited that it couldn't be perfect because life changes, new proteins appear, tissues age, and cells mutate. Well, what was derived from all of that is that the question changed again. If the thymus trains soldiers, who watches over the soldiers when they are already outside? And there, the forgotten piece finally fit. In the 1990s, Japanese immunologist Shimon Sakaguchi did something brilliant and simple, so simple that it was impossible to ignore. He took healthy mice and removed a small subgroup of T lymphocytes, but he didn't remove the aggressive ones, not the ones that attack infections, but that silent group that no one yet fully understood. And the result was absolutely devastating. The mice began to develop massive autoimmune diseases: diabetes, intestinal inflammation, organ destruction, terrifying. And there were no viruses, no bacteria; that is, the immune system was attacking itself. When Sakaguchi, in view of this, returned those cells to the animal, the chaos stopped. And there, science had to accept something fundamental: immunological tolerance is not passive; it's not "let's do nothing." No, it's an active process that requires specialized cells to brake situations. You'll ask me, brake what exactly? Well, to brake the attack when there is no longer an enemy, to brake inflammation before it becomes chronic, to brake the soldiers who have survived the thymus but are nevertheless pointing in the wrong direction, to brake friendly fire. In short. Well, those cells finally received their current name: regulatory T cells, Tregs. They don't replace the thymus; they complete it. The thymus trains the army, and the Tregs prevent civil war. If the other soldiers are children fighting in a playground, the Treg is the wise teacher. The one who doesn't use force, doesn't carry weapons. The Treg approaches the soldier who is shooting, puts a hand on his shoulder, and says, "Friend, calm down, this is not an enemy. We are in our own home. Lower your weapon, please." And shortly after, other researchers like Berry Branc and Fred Ramsdell discovered something even more striking. All these cells depended on a single central switch, a gene without which the brakes simply cannot exist. And that switch gene is called Foxp3. When Foxp3 fails, the immune system doesn't just become weak; it becomes uncontrollable. And we will talk about it in a few minutes. Well, the most powerful thing of all was that this didn't remain an academic hypothesis. The Nobel Prize in Physiology or Medicine in 2025 was awarded to Shimon Sakaguchi, Mary Branc, and Fred Ramsdell for their discoveries on how immune tolerance is maintained outside the thymus. That is, how the immune system regulates itself so that it doesn't attack us. Sakaguchi identified the regulatory T cells, the Tregs, which brake the attack, and Branc and Ramsdell demonstrated that a master gene, Foxp3, is essential for that regulation to exist. This award recognizes that control, not just war, is the most important part of the immune system's purpose. For decades, we believed that the problem with the immune system was that it didn't attack enough. And today we know that often the real problem is that no one tells it when to stop. This finding not only changed textbooks; it explains why millions of people develop autoimmune diseases and why others don't. And it's one of the reasons why we are where we are today.
Well, all of the above has led us to a central idea. The immune system is not regulated with weapons; it is regulated with messages. Tregs are not police officers who shoot; they are authority, they are the sheriff. And authority doesn't shout; it usually speaks. And how does the sheriff convince the soldier? Through chemical words called anti-inflammatory cytokines. And cytokines are basically chemical messages, phrases, orders, and biological whispers. The most important of these cytokines is interleukin-10. IL-10 is a chemical message that directly and immediately turns off inflammation. They also use TGF-beta, which helps repair tissues damaged by the fight. And when interleukin-10 was discovered, many scientists scorned it because it didn't attack, it didn't destroy, and it didn't inflame. And so, what did they do? They called it the "cytokine of surrender." But today we know something radically different. IL-10 is not synonymous with surrender; it's a true damage control. IL-10 tells the soldier, "Stop shooting, reduce intensity, and don't escalate the problem." In other words, it's an immediate ceasefire. Without IL-10, inflammation doesn't turn off. The response becomes chronic, and healthy tissue begins to suffer. And here's the key: the main producers of IL-10 are Tregs. Without sheriffs, there isn't enough IL-10, and without IL-10, the fire never goes out. But a good sheriff not only puts out the fight; he also repairs the damage afterward. And that's where TGF-beta comes in, which is the signal that says, "The danger has passed; now it's time to repair and rebuild." That is, it acts on tissue regeneration, healing, and restoration of balance. And again, Tregs are one of the key sources of TGF-beta. And without Tregs, not only is there an endless attack, but there is also poor repair of inflammatory scars. You end up with fibrosis and progressive deterioration. In other words, without sheriffs, we would die within days, devoured by our own immune system. The health of your cathedral depends directly on how many sheriffs you have patrolling your hallways.
And now let's pause again, because that's a lot of information I've just given you. I hope you're not getting scared and that you see it and that it serves as a general framework that can make sense of the only thing that is truly important and that you should really take away. There are messages that turn off the war within your body. That is, there is a solution. Well, and to complete the general picture, for a sheriff to be respected by the soldiers, he needs a badge. In biology, that badge is a protein manufactured inside the cell thanks to a master gene we spoke about a while ago, called Foxp3. Foxp3 is a transcription factor. Think of it as the instruction manual that tells a cell, "From now on, you are not a warrior. You have become a diplomat whose goal is peace." Foxp3 is not just another gene; it is actually one of the few genes that, when it fails, turns the immune system into your worst enemy. If the Foxp3 gene is on, meaning it's expressed, the cell becomes a sheriff, a Treg. If the gene is off, meaning it's silenced, the sheriff disappears, and chaos takes over the body. See how important it is. In fact, there is a terrible disease called IPEX syndrome. Children who suffer from it are born with this gene broken, and the result is that their immune system attacks all their organs at once, and within days, despite being very strong, they die. I told you about it at the beginning of the video, but what's interesting about this is that it's definitive proof that Foxp3 is the master of peace. Sadly, this IPEX syndrome is not a theory; it's the clinical demonstration that without Foxp3, life becomes self-destruction. But breathe, because this is not your case. You do have this gene, and the question is simply how it is expressed. And the good news is that through epigenetics, that is, what we eat, how we breathe, or how we live, we can help this gene to always be on and, pay attention, manufacturing sheriffs. To give you a very simple summary of what I've just told you: IL-10 is the order to stop. TGF-beta is the order to repair. Tregs are those who issue the orders, the sheriff. And Foxp3 is who decides when to stop. And to focus on what truly matters to us, longevity doesn't depend on how many enemies you defeat; it depends on how many times your body and you know how to say "enough" in time.
But there is still one matter to clarify. Many ask me, "But, José María, why does my body, despite being so wise and knowing all that we know, despite everything, why does it attack me?" And the answer is usually molecular mimicry. Molecular mimicry occurs when a free virus, bacterium, or pathogen has fragments, that is, antigens, that closely resemble your body's own proteins. Your immune system learns to attack the invader, and up to this point, everything is perfect. What's the problem? The problem arises when that resemblance is too good. And to give you an image that might help you understand it, imagine a virus entering your body that happens to have a jacket very similar, for example, to a protein in your thyroid. Your army learns to shoot at that jacket. The problem comes when that virus dies, meaning it has been killed, but the soldiers see your thyroid and think it's still wearing the same jacket, and therefore, bang, bang, bang, they shoot again. Now I'm going to give you more examples because they are very real, and it's likely that they could be useful to you or someone close to you. If so, don't hesitate. Share the video with him or her. Imagine a very common infection, a streptococcus. The immune system learns to recognize and attack it. All of this is fine. In short, it's what it has to do. But the problem arises when that streptococcus happens to resemble a part of your own body too closely in its form. In some cases, it tends to resemble the heart valves. The soldier who has learned says, "This is dangerous." And when he sees something similar again, what he does is shoot, but he doesn't shoot at the bacteria. What he is doing is shooting at your own valves and ends up generating what we call rheumatic fever. I'll give you another example. Some viruses have fragments that closely resemble myelin. Myelin is the insulating layer of your nerves. The immune system attacks the virus, but then it no longer distinguishes well and begins to attack the myelin. It's not really because it wants to destroy you, but because it wants to defend you and believes it has to keep fighting. And that's when multiple sclerosis appears. Let's go to another case. In the intestine, we coexist with thousands of bacteria. If some resemble the intestinal tissue too closely, the immune system goes on constant alert, and if no one brakes that response, inflammation remains installed in your body. This is what we see in diseases like Crohn's, for example. And one more. Some viruses present a dangerous similarity to the cells of the pancreas, that is, those that produce insulin. And the immune system, as it is prepared to do, attacks the virus, but then ends up confusing the target and ends up destroying those cells, and then type 1 diabetes appears. And now look closely at something important. In all cases, the problem is not that the immune system attacks once. The problem is that no one is telling it when to stop. Molecular mimicry explains why the system gets confused, but Tregs, the sheriffs, explain why the confusion turns into disease. The army is not bad; it's simply confused. And it's confused because you don't have enough sheriffs who are capable of correcting the error. That's why, in this series on rebuilding the cathedral, we don't want to lower defenses, that is, immunosuppression. What we want is to increase education, immunomodulation. And we want more sheriffs, not fewer soldiers. The problem is not that the army makes a mistake once; the problem is that without a sheriff, that mistake becomes a habit. And it's important to clarify this because the reality is that mimicry doesn't start the problem; it simply makes it or turns it into a chronic problem because it finds no brakes or because the brakes don't work correctly. So that you can understand it from another perspective, we all have infections, meaning we all suffer from molecular mimicry. We activate aggressive lymphocytes, and we also generate inflammation. But that is not the disease; that is simply life. The difference is not in being healthy and activating the immune system. The difference is in knowing or being able to deactivate it in time.
In situations like the ones I've described, the system has two possible outcomes when an immune attack occurs due to viruses, bacteria, stress, or trauma. First solution: When the system has its brakes operational, meaning when Tregs function, Foxp3 coordinates, IL-10 is released, and TGF-beta is activated, the attack is turned off. Shortly after, the tissue repairs itself, and the episode is closed. That is, the result is that the person recovers, and neither disease nor residue remains. And the conclusion at the end is that nothing serious happened. But now let's go to the second option. When the system has no brakes, Tregs are insufficient or dysfunctional. Foxp3 is silenced or altered, and IL-10 is not enough. Inflammation does not turn off; the attack becomes chronic, and the tissue enters into continuous damage. What do you think the result is? Well, very simply, the response becomes identity. Autoimmune disease appears, and the body attacks itself relentlessly. Having said all of the above, keep one thing clear. We are not born without brakes. What happens is that the brakes wear out. And what are the factors that reduce Tregs and Foxp3 over time? Chronic stress, sustained inflammation, lack of deep sleep, disruption of the circadian rhythm, repeated infections, immunological aging, energy deficit or low voltage, and a constant inflammatory environment. That's why a young person usually recovers, and the same person years later no longer recovers. And it's not because the body becomes bad; what happens is that it loses its regulatory capacity. The difference between healing and the problem becoming chronic is a single word: brakes.
And now let's talk a bit specifically about them. The question is, do we have the possibility of manufacturing more sheriffs, that is, more Tregs, in our kitchen and in our daily lives? Well, it turns out we do. Take note, because what I'm going to give you now is the practical manual. It doesn't substitute for medical treatments, of course, but it does explain why many treatments fail when the system is without brakes. And another thing, one more thing: you don't have to start it tomorrow. What I propose is that you dedicate time to understanding why each piece has its value and counts. And having clarified all of the above, I will present four ways through which you can act. The first, vitamin D3, the master hormone. Vitamin D, as you know, is not a vitamin; it is an epigenetic signal. And the vitamin D receptor enters the nucleus of your cells and directly binds to the Foxp3 gene to turn it on. Without vitamin D, it's very difficult to have sheriffs, and you need optimal levels between 60 and 80 ng/mL. And my advice regarding the doses you might need, if you need them, is to consult with your doctor. The second, short-chain fatty acids, that is, butyrate. Your good gut bacteria, that is, the microbiota, produce a substance called butyrate when you eat fiber and resistant starch. And butyrate is the food that trains Tregs in the intestine. A healthy intestine manufactures sheriffs. Third, omega-3, resolvins. Oily fish and krill oil provide fatty acids that produce resolvins which, as their name suggests, serve to resolve the battle and tell the army, "The war is over. Pick up the debris and leave." And fourth, vagal breathing. As we saw in the vagus nerve series, when you breathe slowly and especially deeply, you send a signal to the immune system. You are telling it, "We are safe." Because chronic stress kills sheriffs, but inner peace multiplies them.
Well, after all this journey, there is only one more thing to say. Reclaiming control of your army is the highest act of dignity. You cannot be free if you live in fear of your own biology. Your cathedral needs light, voltage, but it also needs laws, that is, Treg sheriffs. And when the sheriff returns to town, inflammation subsides, pain disappears, and energy becomes available again for living, not for fighting. Autoimmunity should not be a life sentence. It's a sign that your system has lost command. That's what it is. But today you know how to try to give it back. If you feel that this message can bring peace to someone who lives at war with their health, you would do me a great favor, and them too, if you share the video. Let's try to help more people awaken their inner sheriff. In the next video, we will talk about lymphatic cleansing, or how to activate your brain's sewage system while you sleep. And all of that so that rust simply doesn't block your light. And with that, as the cartoons used to say, that's all for today. As I always say, onward. Onward.