My wife is not happy with me.
See, for the past several days, I've been randomly grabbing drinking glasses from the shelf in the kitchen…
…and peeing into them.
And yes, I realize that now you will likely never want to join me at my home for a dinner party.
So why the heck am I urinating into our family's kitchenware? It's all about better living through science and figuring out ways to live longer and feel better (at least that's what I tell my wife to appease her). It's also about my sheer curiosity and desire to delve into an N=1 experiment in self-quantification with urinalysis. It's also because I've been too lazy to order one of those special urinalysis specimen cups with the cute plastic lid.
And let's face it: with my relatively frequent use of a three day gut testing panel, my wife is already somewhat accustomed to giant Fed-Ex bags full of poop tubes sitting in the fridge, so urine can't be all that bad, right?
Anyways, in this article, you're going to learn exactly why I think it's a good idea to occasionally study one's own urine, and you'll also discover 10 very interesting things your pee can tell you about your body. Enjoy, and as usual, leave your questions, thoughts, feedback, and stories of your own adventures in urinalysis below this post.
The History Of My Interest In Urinalysis
Two years ago, I first became interested in urinalysis when I discovered a new start-up called “uChek”.
The premise of uChek was quite simple.
People with diabetes who want to check the amount of glucose in their urine would simply be able to download uChek to their iPhone or iPad. Then, after a “mid-stream collection,” (yes, that's exactly what it sounds like and, in my experience, despite my Private Gym training, can be quite difficult to pull off) a urine test strip, also called a “dipstick”, is dipped into the pee sample.
After a few moments, colors appear on the test strip that reflect the presence of specific compounds in the urine, such as glucose, ketones, hydration status, pH, etc. The user would then photograph the test strip with the phone or pad camera and the app would then compare the colors and allow you to email the results, store them or chart them over time.
Although I'm not diabetic, the concept of being able to us an app like uChek to conveniently self-quantify was, to me, quite intriguing.
So I headed on over to the uChek IndieGoGo page, invested my eighty-four hard-earned dollars into the crowdfunding campaign, then sat back with baited breath and a bladder full or urine for my fancy uChek iPhone attachement to arrive in the mail.
Hooray! I was about to get a “medical lab in my iPhone”, and here's the e-mail to prove it:
Trouble is, apparently the FDA caught wind of the uChek app.
And the US government, bless their hearts, in an effort to protect us all from peeing on our phones, claimed that using an app like uChek to read a urine analysis strip changes the phone's components into a medical testing system subject to FDA approval. Plus, there's the issue with potential for electronic storage and transmission violating HIPPA regulations, which is the same reason the Quantified Toilet generated such controversy.
In a letter to Biosense Technologies (the makers of uChek) the FDA said…
…“since your app allows a mobile phone to analyze the dipsticks, the phone and device as a whole functions as an automated strip reader.”
And then, as you can read in “Why the FDA Took the Piss Out of uChek, a Urine Analysis App“, the FDA shut uChek down. Here's the e-mail I subsequently received:
That was a sad day.
Since then, there's been no word from uChek, and after spending several weeks mildly depressed that I could not urinate onto my phone as promised, I got over it and moved on.
Using Urine Data To Drive Optimal Hydration Levels
But recently, my interest in urinalysis has been freshly renewed.
As you know if you read my recent infrared sauna article, Shattering The Myths Of Detox Therapy, Infrared Saunas, Health Scams & More, I've been spending copious amounts of time sweating in a sauna.
And if you read my coffee enema article, The Bulletproof Coffee Enema: Everything You’ve Always Wanted To Know About Coffee Enemas (But Were Afraid To Ask), then you also know that I'm no foreigner to shoving tubes up my backside that could potentially cause my colon to drain my body of fluid and electrolytes.
Finally, of course, I lose plenty of minerals and water via my unnaturally high amounts of exercise to prepare for everything the masochistic endurance events in which I compete, most notably of late the Spartan World Championships and the World's Toughest Mudder.
Sure, I could simply use the color of my urine (e.g. yellow vs. clear) to determine whether these activities are leaving my body a touch dehydrated. But as Dr. Stacy Sims, a previous podcast guest alludes to in her article “How Much Do I Need To Drink” as TJ Murphy mentions in the recent LAVA article “How Can You Use Data Drive An Optimal Hydration Level“, a measurement called urine specific gravity can give you an even more quantified, precise way to determine your hydration levels.
Urine specific gravity is relatively straightforward. Using urine reagent test strips, which you'll learn more about momentarily, you can look at a marker called Specific Gravity (SG).
-A normal hydrated status is an SG of 1.005 to 1.015.
-An SG of 1.020 indicates you’re approximately 1% dehydrated of total body water volume.
-An SG of 1.025 means you're probably approaching a point where physical and mental performance could be inhibited.
That's it. Easy eh? Using this data, you can then do things like identify certain activities that dehydrate you, or choose when or when not to consume extra water and minerals.
But the magic of staring at your own pee doesn't stop there. Here are some other cool things your pee can tell you about your body.
How Urinalysis Works
Urinalysis test strips consist of a ribbon made of plastic or paper of about 5 millimeters wide, just like you may use test hot tub or pool water (except hopefully there is no pee in your pool). You can get Urinalysis strips on Amazon for about 7-20 dollars for 100 strips. I got the Cybow brand, and it doesn't appear there's a huge difference among brands.
The plastic strips have pads infused with chemicals that react with the compounds present in your urine to produce a specific color. On paper strips, the reactants are absorbed directly onto the paper. Paper strips are often specific to a single reaction (e.g. pH measurement, pregnancy, ketones etc.), while the strips with pads, the more common ones you'll probably be using, allow you to look at the concentration of several urine parameters all at once.
Once you've dipped the strip into your urine for about five seconds, you then remove the strip and either compare the pad color with a color scale on the outside of the strip bottle, or an app like the Siemens Urinalysis Guide App or the Urinalysis Made Simple App by Quantmetrix. Values are usually reported as trace, 1+, 2+, 3+ and 4+ or as milligrams per decilitre. The time taken for the full appearance of the test results on the strip can vary from a few minutes after the test to 30 minutes after immersion of the strip in the urine (depending on the brand of product being used).
The color comparison chart on the back of most bottles or on a phone app will look something like this:
One other thing: proper technique can definitely come in quite handy.
For example, leukocytes and erythrocytes precipitate at the bottom of the container you pee in, and may not be detected if you don't properly mix the sample. So give your urine cup a little stir or shake. Hell, use a latte frother for all I care, but just don't make the same mistake as me and let your spouse see you defiling kitchenware.
If an excess of urine remains on the strip after it has been removed from the test sample, this can cause the reagents to leak from the pads onto adjacent pads, resulting in mixing and distortion of the colors. To remedy this, I recommend briefly tapping the edge of the strip over the mouth of the container to remove excess urine. Needless to say, and speaking once again from personal experience, this is an activity best relegated to the bathroom, not the kitchen counter.
10 Things Your Pee Can Tell You About Your Body
OK, now here's the fun part. Let's jump into what exactly you can learn from the average urinalysis strip.
In a nutshell, you get glucose, bilirubin, ketone, specific gravity, blood, pH, protein, urobilinogen, nitrite, and leukocytes, and this data provides information regarding the status of everything from carbohydrate metabolism to kidney and liver function to acid-base balance to bacterial infection.
Let's take a closer look at what these ten variables mean for fitness enthusiasts, and which ones athletes, self-quantification nerds and biohackers alike should pay close attention to.
1. Specific Gravity
The specific gravity of urine is simply a measure of the density of the substances dissolved in your urine, and it depends on both the number of dissolved particles and their mass. Molecules with the greatest mass contribute more to the measure of specific gravity than smaller molecules. The more dehydrated you are, the less water in your urine and the greater the concentration of the particles in your urine. The colours vary from dark blue with a reading of 1.000 to yellow for a reading of 1.030.
Elevated protein concentrations produce slightly elevated specific gravity results as a consequence of the indicator’s protein error. This means that if you have a lot of muscle damage from, say, a hard run or weight training session, your urine strip may indicated a slightly greater state of dehydration than you're actually in. Also, urine samples with a pH above 6.5 give lower readings of specific gravity, so the manufacturers of urinalysis strips recommend that you add 5 units to the specific gravity reading when the pH is greater than 6.5.
On a urine strip, the leukocytes test looks for the presence of leukocyte esterase, which is present in white blood cells like monocytes and granulocytes (of the neutrophilic, eosinophilic and basophilic varieties). High numbers of leukocytes can indicate a urinary infection or the upcoming onset of an illness such as a viral or bacterial infection. Kidney inflammation, STD's and yeast infection can also jack up leukocytes. One day after hard training, any positive leukocyte results could indicate inadequate recovery, and the need to sleep, hydrate, and engage in as many recovery protocols as possible so you bounce back.
False negative results for leukocytes are associated with elevated concentrations of protein (greater than 500 mg/dL), glucose greater than 3 g/dL, or high levels of oxalic acid or ascorbic acid. Urine with a high specific gravity can also cause leukocyte crenation, which can impede the liberation of the esterases and also give a false negative result, meaning your leukocytes are high but the strip isn't showing it.
Your intestinal bacteria convert the bilirubin that is excreted by the bile duct into your intestine into urobilinogen and stercobilinogen. Part of the urobilinogen is reabsorbed in the intestine then circulated in the blood to the liver where it is excreted. But some of this recirculated urobilinogen is filtered out by the kidneys and appears in your urine.
Any deterioration in liver function reduces your ability to process the recirculated urobilinogen, and the excess that remains in the blood is filtered out by the kidneys and appears in your urine. So high urobilinogen can indicate a beat-up liver. Thus far in my N=1 experimentations with urinalysis, I haven't tested following a heavy bout of drinking, but it could be interested to see how much liver function is impaired. Feel free to raise your hand in the comments section if you'd like to volunteer for that experiment. BYOB.
The term ketones or ketone bodies actually refers to three different products involved in the metabolism of fatty acids: acetone, acetoacetic acid and beta-hydroxybutyric acid. Elevated concentrations of ketones are not usually found in your urine, since most ketones are completely metabolized to produce ATP, carbon dioxide and water. However, very low carbohydrate metabolism or burning a very high amount of fat can lead to a high appearance of ketones as a by-product of the metabolism of fat.
An increase in fat metabolism can be the result of starvation or malabsorption, the inability to metabolize carbohydrates (such as might occur in diabetes) or due to nutrient losses from illness, vomiting or just not eating enough food.
Now here's something very important for you to know: urine strips only show excess ketone bodies exerted via urine. In most cases, in the average, healthy active person, these excess ketones are, in fact, wasted calories that you didn't metabolize.
If you're in ketosis, eating a high-fat diet, or have been restricting carbohydrates for a long period of time, you're probably keto-adapted (AKA a “fat burning machine“), and this means that even if you are in ketosis, urine strips aren't going to tell you that. This can happen in as few as two weeks into a low-carb, high-fat or ketosis diet, and it's why I recommend breath testing using a device like this rather than urine testing for “true” ketosis in fat-adapted folks. For more details on the nitty-gritty science behind this, read this post at Ketopia.com.
Basically, if you are keto-adapted, you will exert less ketone bodies via urine. This means that you may show high blood or breath ketones and low or zero urine ketones. Although I'm generally in ketosis much of the day, I rarely saw elevated ketones in my urine, including after a 16 hour fast and after a 16 mile unfed run.
Finally, changes in hydration can affect the concentration of urinary ketones. A high water intake may dilute the concentration of ketones in the urine.
Under normal conditions nearly all the glucose removed in the glomerulus is reabsorbed in the proximal convoluted tubule of your kidneys. But if your blood glucose level increases dramatically or you have diabetes mellitus, the capacity of the tubule to reabsorb glucose is exceeded (a condition known as renal reabsorption threshold). For glucose, this threshold is between 160-180 mg/dl, which is pretty dang high blood glucose values, but values that can cause glucose to appear in urine.
The most representative results of glucose concentration in urine come from samples obtained at least two hours after food is eaten, and please allow me to be clear: you'd have to eat a crapola of glucose to get your levels up to 160-180 mg/dl. So only when glucose gets extremely elevated, such as in uncontrolled diabetes, does the high glucose present in the blood enters the urine.
Exceptions exist, however. Nondiabetic glycosuria, also known as renal glycosuria, is a condition in which glucose appears in the urine despite normal blood levels. There are no symptoms associated with this condition, and it occurs in as many as 50% of pregnancies, especially in the third and fourth months. So unless you're diabetic or pregnant, you probably won't be paying much attention to this value.
Your lungs and kidneys are the main regulators of your acid and alkaline balance, which is maintained through the excretion of acidic hydrogens in the form of ammonia ions, phosphate, organic acids and the reabsorption of bicarbonate through filtration in the kidneys. The pH of urine normally varies between 4.5 and 8, with the first urine produced in the morning generally being more acidic and the urine produced after meals generally more alkaline.7.0 is a neutral pH. The higher the number, the more basic it is. The lower the number, the more acidic your urine is. The average urine sample tests at about 6.0, although it's tough to find normalized reference values for urine pH, as the variation is very wide.
Diets very high in animal proteins tend to produce acidic urine, while diets mainly comprised of vegetables tend to produce alkali urine. If your urine pH is very low, this could indicate an acidic environment for kidney stones or any of the following conditions:
Meanwhile, a higher-than-normal urine pH could indicate:
-low stomach acids
-pyloric (stomach sphinchter) obstruction
-respiratory alkalosis (breathing off too much carbon dioxide)
-urinary tract infection
Bilirubin is a by-product of haemoglobin degradation. The haemoglobin that is released after your liver and spleen withdraw old red blood cells from circulation is degraded into iron, protoporphyrin and protein. The protoporphyrin is converted into bilirubin that passes through the circulatory system bound to protein. The kidney is unable to filter out this bilirubin that is bound to protein, but, the bilirubin is conjugated with glucuronic acid in the liver to form water-soluble conjugated bilirubin. This conjugated bilirubin should not normally appear in the urine, and should be excreted directly from the intestine in bile. Intestinal bacteria reduce the bilirubin to urobilinogen, which is later excreted in your feces as sturcobilin or in the urine as urobilin.
However, bilirubin can appear in your urine when this normal cycle is altered due to the obstruction of the biliary ducts (e.g. liver or gallbladder dysfunction) or when the kidney’s functional integrity is damaged. This allows the escape of bilirubin into the circulation, and you'd see this in conditions like hepatitis or liver cirrhosis.
So urinary bilirubin is an early indication that your liver is freaking beat up.
Something called “proteinuria” (protein in your urine) is often associated with early kidney disease, but it can also indicated excessive muscle damage, dehydration or inadequate recovery. Normally, urine contains very little protein, and typically less than 10 g/L or 100 g per 24 hours is excreted.
A normal protein color should show a yellow reagent. Green coloring on the yellow indicates a positive marker for protein presence. A ton of green probably indicates the dreaded condition of rhabdomyolysis. While it is completely normal to have a bit of green in the few hours after exercise, if protein is still positive in the morning after an exercise session, you still have some pretty serious muscle damage and inadequate recovery happening.
The test for nitrites is a screening method for possible asymptomatic infections caused by nitrate-reducing bacteria. For example, some bacteria that most commonly cause urinary tract infections, such as Escherichia coli, Enterobacter, Klebsiella, Citrobacter and Proteus, have enzymes that reduce the nitrate present in urine to nitrite.
So basically, if your urinalysis shows nitrites, you probably have a urinary tract infection (UTI) and you should probably listen to this podcast.
Blood can be present in your urine either in the form of intact red blood cells (hematuria) or as the product of red blood cell destruction, hemoglobin (hemoglobinuria). Blood present in large quantities can be detected visually. Hematuria produces cloudy red urine, and hemoglobinuria appears as a clear red specimen. The presence of intact red blood cells in your urine typically signifies some kind of blood loss in the lower part of the urinary tract, like the urethra, bladder or ureters, and high hemoglobinuria or hematuria can also indicate kidney inflammation..
The Results Of My N=1 Experiment With Urinalysis
OK, so now that you're a urinalysis analysis ninja, let's take a peak at my results in full iPhone photo glory, shall we?
Day 1, morning waking. Note that Specific Gravity seems to indicate mild dehydration. Also a very “alkaline” pH, and a very small amount of ketones. Nothing earth-shattering here, aside from the fact that I must lose more water than I thought during my overnight sleep, and despite most people having acidic morning urine, mine appears to be alkalinic.
Day 1, morning 30 minutes after eating big-ass smoothie. No significant rise in blood glucose, probably because my smoothie is mostly fats and vegetables, with only about 20g of protein (recipe here). Specific Gravity still shows some dehydration, and my urine has become slightly more acidic.
Day 1, afternoon pre-workout. Well, I'm alkaline again, but still slightly dehydrated. Crap. If I'm learning anything here, it's that I need to drink more water, which surprises me since I already consume about a 16 ounce glass of water every hour or so. Perhaps the combination of sauna, enemas and exercise dehydrates me more than I suspected.
Day 1, early evening post-workout. Note the proteins from muscle damage in my urine. Cool. All those pull-ups must have done something.
Day 2, morning, 60 minutes post-coffee enema. Definitely still a bit dehydrated, possibly more than usual. By the way, you may have noticed that the urinalysis strips I'm using show an eleventh parameter: ascorbic acid. Ascorbic acid, or vitamin C, is a water-soluble vitamin important in our diet, and excess amounts of vitamin C can be excreted via the urine if the body has enough. Considering the huge amount of plant matter I consume, it's no surprise I have vitamin C in my urine.
Day 2, morning 30 minutes after eating big-ass smoothie. A-OK, except for Specific Gravity. Must. Drink. More. Water.
Day 2, afternoon pre-workout. Note my beautiful pH of 7. Nice.
Day 2, early evening post-workout. Yep – proteins in the urine again. But interestingly, a workout doesn't seem to make my pH more acidic.
Day 3, morning waking. Still some proteins in the urine. Uh-oh: this indicates inadequate recovery. Probably because I finished my workout then immediately went hunting for nearly two hours…
Day 3, after 16 hour fast, skipping breakfast. Note lack of urinary ketones, despite fast. Scroll back up and read what I wrote about ketones to understand why I'm burning them so they're not showing up in my urine.
Day 3, after a 16 mile run. Definitely dehydrated. No protein in urine, however. It seems a weight training session seems to jack up muscle damage levels even more than a very long run. Interesting.
Day 3, 30 minutes after a big dinner that included 100 grams of rice-based carbohydrates. Even that didn't seem to make a dent in urine glucose levels.
Day 4, morning, post-30 minutes infrared sauna. Specific Gravity pretty dang high. Not to kick a horse to death here, but it's looking like many of my daily practices dehydrate me. If there's one big thing I've learned here, it's that I need to drink more water even though I'm already drinking quite a bit. I've always been under the impression that the high Blood Urea Nitrogen (BUN) I've seen on my blood test results were due to muscle damage, but it's likely they may also be due to me not drinking enough water. And again, I must emphasize that up until this point, I have been at nearly 16oz of water hour most of the day!
I'm obviously only a few days into this experiment, which is why you see just four days of urinalysis results and yes, I could have quantified this with a fancy spreadsheet, and perhaps I still will, but for now these photos suffice to give you a very good idea of the kind of things you can do with a urinalysis. Stay tuned, as I will reveal even more results (likely on the Facebook/BGFitness page) as I drink more water and see what it does to Specific Gravity.
As you read this, I'm on a plane traveling back from the Biohacker Summit in Finland (so of course it seemed perfectly fitting to do a write-up on self-quantifying a bodily fluid).
But when I land, I'll check the comments section to see what kind of questions you have about urinalysis, and hopefully to hear about some of your own results. In the meantime, I think that for just a few bucks and a hundred urinalysis strips, this form of self-quantification is well worth the bargain cost, and can give you some interesting insight into a cool grab-bag of parameters.
Enjoy your pee, and for heaven's sake, clean the drinking glass afterward.
Do you have questions, comments or feedback about urinalysis, what your pee can tell you about your body, dehydration, ketosis,your own results from your urinalysis or anything else I discuss in this article? Leave your thoughts below.