Full transcript of “6 Things That Quietly Damage Your Kidneys Every Day (Doctor Explains)”. Click a timestamp to open the video at that moment. Need another video? Use the YouTube transcript generator.
0:00 Most kidney failure doesn't announce itself with pain or symptoms. By the time people notice something's wrong, they've often already lost more than half of their kidney function. And the scary part is that the damage usually begins years earlier with habits that feel completely normal and completely harmless. My name is Dr. Alex. And over the last decade working in emergency medicine, I've watched countless people arrive with kidney problems that could have been prevented. Now, what fascinates me isn't just the medical complexity, but the patterns, the same behaviors, the same misconceptions, the same slow accumulation of damage that nobody talks about until it's too late. So, what I want to share in this video is what I've
0:47 learned over the years and hopefully teach you something that might help you live longer and live more healthily. And in return, if you find this video valuable by the end, then please consider subscribing to the channel because it really does help these videos reach more people who might benefit from them. So, here's what makes kidney damage particularly sneaky. So you've got around 1 million tiny filtering units in each kidney called nephrons and these are remarkably resilient. You can lose 60 to 70% of your total kidney function before you experience any symptoms. That reserve capacity is brilliant for survival, but it creates this dangerous blind spot. People assume everything's okay because they feel
1:33 fine, but their kidneys are actually quietly deteriorating. So, I check kidney function in the vast majority of medical patients in the emergency department. And in all honesty, it's uncommon for me to find a completely normal kidney function on a blood test in someone over the age of 50 these days. So, today I'm going to walk you through six common things that gradually damage these organs. And more importantly, I'm going to explain what's actually happening at a physiological level. And if you stay until number four, then I'll debunk one of the most common myths about salt that even most doctors get wrong. So, first on the list today, and probably the most unexpected for many people is something that's sitting in bathroom cabinets across most
2:20 of the country, and this is anti-inflammatory painkillers. things like ibuprofen, neproxin, diclophenac. These NSAIDs, as we call them, non-steroidal anti-inflammatory drugs, NSAIDs, these are incredibly common. If you've got a headache, then take ibuprofen. If you've got back pain, then take ibuprofen. If you're sore after the gym, then people take ibuprofen every day. And speaking personally, if I have a headache, then paracetamol doesn't really work for me. only ibuprofen does. It's a really, really common and effective painkiller. The thing is, your kidneys rely on a delicate balance of chemicals called
3:06 prostaglandins to maintain their blood flow. These prostaglandins tell the small arteries feeding your kidney filters to stay dilated, keeping pressure stable and filtration running smoothly. But when you take NSAIDs like neproxin or ibuprofen, you're blocking the enzymes that produce these prostaglandins. The result is that those arteries constrict, blood flow to the kidneys drops, and filtration rate decreases. For most healthy people taking the occasional dose, this isn't a problem, so don't be too concerned here. the kidneys recover quickly. But if you combine chronic NSAID use with dehydration, or if you take them regularly if you're older, say more than a week at a time, or if you already have
3:53 high blood pressure, then you're creating this perfect condition for an acute kidney injury. What makes this really dangerous is something we call the triple whammy in emergency medicine. That's when someone combines NSAIDs like ibuprofen with blood pressure medications like an ACE inhibitor and also water tablets. Each one individually affects kidney blood flow, but together they can cause serious damage. And we see patients taking this combination of medication all the time. It's honestly so common. And what happens is the kidneys become eskeemic. They become starved of oxygen and repeated episodes lead to permanent scarring. Moving on to number two, which is the leading cause of kidney disease,
4:38 and that is high blood pressure. Now, what many people don't realize is that hypertension doesn't just reflect kidney damage, it actively causes it. Your kidneys are high pressure filtration systems by design. Blood enters under significant force to push fluid and waste through those tiny filters that I mentioned earlier. When you have chronic high blood pressure, you're essentially forcing too much pressure through these delicate structures, the walls of the glomemeuli, these microscopic filtering units, start to thicken and scar in response, and we call this glomemeulos sclerosis. Now, as the scarring progresses, proteins that should stay in
5:24 your bloodstream begin leaking into your urine. Each damaged nephron dies off. And here's where it gets a bit worse because the remaining healthy nephrons have to work harder to compensate. They start filtering more blood at higher pressures, which accelerates their own decline. And this creates a vicious cycle because damaged kidneys can't regulate blood pressure properly because they're part of the hormonal system that controls it. Poor regulation leads to higher blood pressure, which causes more kidney damage, which worsens blood pressure control even more. Round and round it goes. Blood pressure above 130 over 80 in someone with existing kidney disease significantly accelerates the progression towards complete failure.
6:10 Number three on the list is something that sounds a bit too simple to even matter and that is chronic mild dehydration. Not the acute dehydration that sends people to hospital but this persistent low fluid intake over months and years. and my dad and my father-in-law are guilty of this. So when your body doesn't get enough water, blood volume decreases slightly. That reduction means that less blood reaches your kidneys. In response, your body activates hormonal systems, particularly something called the reining angotensin aldoststerone system or RAS. Now, this system is designed to conserve water and maintain blood pressure in the short term, which
6:56 is useful when you're genuinely dehydrated, but chronic activation has consequences. The hormones cause your blood vessels to constrict, including those in the kidneys. That constriction increases pressure within the kidney while simultaneously reducing overall blood flow. Now over time this leads to fibrosis essentially scarring of the kidney tissue. As well as that concentrated urine from chronic dehydration increases your risk of developing kidney stones which is one of the worst pains that you can experience. Recurrent stones can cause obstructive damage, blocking urine flow and creating this back pressure that destroys nephrons from the inside out. Now, you
7:42 don't need to drink excessive amounts of water. The goal isn't to have maximum hydration because that can be a bit dangerous sometimes, but persistent mild dehydration creates a low-grade stress on these organs that accumulates over decades. What I would say is if you're someone that doesn't drink that much water or tea or milk or anything like that, then just have a couple of extra glasses of water a day, see how you feel and get your kidney function checked with your doctor. Now we come on to what salt actually does in your body and this is number four and it's something that I find really really interesting. So this is all about high sodium ultrarocessed foods. Now, salt itself doesn't directly poison your kidneys. The damage happens
8:29 through a more indirect route, but one that's just as destructive. Now, here's what most people miss about sodium and blood pressure. Your kidneys are the master regulators of blood pressure, precisely because they control sodium balance. In a healthy metabolic system, the process works really well. You eat salt, your plasma volume temporarily increases. Your kidneys detect this and then excrete the excess sodium and then pressure normalizes. It's a really really elegant feedback loop. But in a metabolically unhealthy system, this feedback loop breaks down. When you have chronically elevated insulin, which happens with insulin resistance and regular consumption of refined carbs,
9:15 then insulin signals to your kidneys to retain sodium. This isn't a temporary response. It's persistent. The kidneys can't excrete sodium normally anymore. So, plasma volume expands and it stays expanded. And what that triggers is the activation of the reenin angotensin aldoststerone system which is the same hormonal cascade that we talked about earlier with dehydration. Now the result is a maintained high pressure state. What this means is that the problem isn't just dietary salt intake in isolation. It's hormonal sodium retention driven by metabolic dysfunction. Two people eating the same amount of salt can have completely different blood
10:01 pressure responses depending on their insulin sensitivity. The person with insulin resistance retains more sodium. It holds on to more fluid and experiences higher kidney pressures from the same dietary intake. Excess sodium causes fluid retention. That extra fluid increases blood volume which raises blood pressure. Higher blood pressure means increased force inside those kidneys that we keep coming back to. You're seeing the pattern now. I'm hoping pressure is the common enemy here. But ultrarocessed foods bring additional problems beyond just sodium content. They drive insulin resistance and systemic inflammation, both of which damage blood vessel function throughout
10:47 the body, including in the kidneys. What you need to understand here is that sodium sensitivity varies enormously between people and much of that variation comes down to metabolic health. Some people's blood pressure responds dramatically to salt intake while others seem relatively resistant. But when you combine high sodium with existing insulin resistance and hypertension, then you're creating the perfect conditions for accelerated nephron loss. The average person consumes around twice the recommended sodium intake. And most of that comes from processed food rather than the salt that you add to home-cooked meals. Now, in a metabolically healthy person, that excess sodium is usually cleared. But in someone with insulin resistance, that
11:33 sodium is retained. And when retention becomes chronic, the pressure becomes chronic. And chronic pressure is what destroys your kidneys. Moving on to number five, which for me is the most important one on the list, and this is poor blood sugar control. Now, diabetes, particularly type 2 diabetes driven by insulin resistance, which we just touched on, it destroys kidneys through lots of different mechanisms simultaneously. Chronic high blood sugar doesn't just float around harmlessly in your bloodstream. glucose molecules, they stick to proteins in a process called glycation, creating what we call advanced glycation endroducts. What these damaged proteins do is they
12:18 accumulate in the delicate basement membrane of your glomemeuli causing it to thicken abnormally. cells within the filter part of the kidney called ptoytes become injured and die and then the supporting structure the meangium expands and becomes dysfunctional. Now in the early stages kidneys actually increase their filtration rate. This hyperiltration might sound a bit beneficial maybe but it's a stress response. It's not a good thing. The increased pressure and workload accelerate the damage. Eventually, you start seeing proteins leak into the urine first in tiny amounts called micro albam in your ear and then in larger quantities and then your kidney function starts to decline. What makes this
13:04 particularly relevant to longevity is that insulin resistance which is the root cause of type 2 diabetes develops years before the actual diabetes diagnosis. During that pre-diabetic period, which I focused on in a lot of different videos, your kidneys are already experiencing the effects of elevated blood sugar and metabolic dysfunction. So, controlling blood sugar early before you're officially diabetic protects these organs in ways that medications can't fully compensate for later. The key blood test to measure here is your HBA1C, which is your average blood sugar over the last 3 months. And most doctors can do this for you. And if you're wanting to learn more about this specifically, then I've got a few other videos on this that you can search for easily. And finally, we reach number six
13:52 on the list. Now, this one requires a bit of nuance because this is where a lot of confusion exists. And this is all about extremely high protein intake in susceptible people. And that word susceptible is really important. Now, let me just be clear from the beginning. Healthy kidneys handle high protein diets without issue in general. If you're young, if you're fit, and you're healthy, and you're using protein shakes, then you're probably fine. So, don't worry. The problem emerges in specific contexts that many people fall into without realizing it. When you consume protein, your kidneys need to filter the breakdown products, particularly something called ura. High protein intake increases the workload
14:39 which raises filtration pressure within the kidney in a young and healthy person with normal blood pressure and no metabolic issues then this increased pressure is easily managed. But if you add in existing chronic kidney disease or diabetes or hypertension or simply older age then suddenly that extra workload becomes problematic. The mechanism centers again on hyperiltration. Remaining healthy nephrons compensate for the damaged ones by filtering more blood at higher pressures. What protein does is that it amplifies this compensatory hyperiltration. Over time, the constant high pressure accelerates the decline of those remaining nephrons. You're essentially
15:26 wearing them out faster. Now, it doesn't mean that you should avoid protein altogether. Obviously, for most people, adequate protein is essential for muscle maintenance, for your metabolic health and longevity. Protein is really, really important. The issue is context. If you already have compromised kidney function, if you're dealing with uncontrolled diabetes or hypertension, then extremely high protein intake may speed its progression. The key here is matching your protein intake to your actual kidney health status. And this is something to speak with your doctor about after you've had your kidney function measured on a blood test. Generally though, unless you've got very severe kidney disease, then the levels of protein that I talk about in my other videos about diet will generally be fine
16:13 for you. Now, looking across all six of these factors, you should notice a pattern. Every single one of these causes damage through increased pressure within the glomemeuli, through inflammation, through oxidative stress, or through fibrosis. Kidney failure isn't random bad luck. It's the cumulative result of mechanical and metabolic stress repeated thousands of times over years and decades. NSAIDs, non-steroidal anti-inflammatory drugs, they reduce the protective blood flow. Hypertension creates excessive pressure. Dehydration triggers damaging hormonal responses. Salt raises blood pressure through insulin mediated sodium retention. Diabetes damages the
16:59 filtration structure and then high protein increases the workload in compromised kidneys. Different mechanisms the same end point which is destroyed nephrons. So what do you actually do with all of this information? Well, if you're at risk, meaning that you have diabetes or hypertension or a family history of kidney disease or if you're over the age of 60, then you need to monitor it. What that means is checking your blood pressure regularly, aiming for below 130 over 80 for most people, unless you're really elderly or frail. It means annual blood test to check your kidney function and urine tests to check for albamin to creatin ratio. What these catch is early damage when
17:47 it's still reversible. You also need to avoid chronic NSAID use unless medically necessary and your doctor will advise here. And remember these are the drugs called ibuprofen, neproxen or dicloanac. You also need to stay adequately hydrated without obsessing over arbitrary water targets. Just try to increase your general consumption throughout the day. You also need to reduce your ultrarocessed food consumption which simultaneously lowers your sodium. It improves blood sugar control and it reduces inflammation. Control blood sugar early, well before diabetes develops as well. And your doctor can really help here. Avoid moderate protein intake if you already have known kidney disease. Again, your doctor should advise here. And just
18:33 remember that your kidneys are vascular organs. The same factors that protect your heart and your brain protect your kidneys. blood pressure control, metabolic health, reducing inflammation. These aren't separate goals. They're all integrated. Protects your kidneys and you're protecting your entire cardiovascular system, your cognitive function, and ultimately your whole lifespan. I really hope you got some value from this video today. If you did, then please give it a like, and I'll see you next time.
