Welcome back to Testosterone Week! If you’re just joining us, I recommend checking out our two previous posts in the series: and . Today we’ll be taking a look at what’s considered a normal testosterone level and how you can get your testosterone levels tested. As I began researching testosterone levels and hormone testing for this series, I quickly learned that there’s a lot of conflicting and confusing information out there — some websites will say that “X” is a normal testosterone level, while another website says “Y” is the ideal range. Even medical labs give conflicting numbers on what’s a normal testosterone level. Why so much confusion? The problem is that there hasn’t been much standardization in hormone testing, particularly regarding T levels. Different labs use different methods (and measurements), which has only created confusion among consumers and even family doctors about what testosterone level results even mean. Hopefully, the current state of confusion will soonchange. The Center for Disease Control here in the U.S. started a project in 2010 to get labs to agree on . It’s slowly gaining ground, but not every lab has signed on. I also learned that the bottom range of what’s considered “normal” by many doctors is actually woefully underestimated. Doctors are telling men who come to them with symptoms of low testosterone, “Well, you’re barely within normal range, but it’s still normal, so… you’re fine!” No, Dr. Everything’s-A-Okay. It’s not fine. I hope in this post I can clarify some of the confusion surrounding testosterone levels and hormone tests. I’ll be straight with you. This stuff is super confusing. I’ve done my best to synthesize all the disparate info out there into an easy-to-read format for the layman and have sought to create the most accessible resource on the web. But, I’m not a scientist or doctor, and may have gotten a few things wrong. If any of you professional endocrinologists see an error, I welcome your corrections. Totaland Free Testosterone Levels Before we begin, I want to reiterate the fact that there are three different types of testosterone floating in your body: free testosterone, SHBG-bound testosterone, and albumin-bound testosterone. When you get tested, there are two tests you can get: total testosterone and free testosterone. Total testosterone is the total amount of T floating in your blood at the time of the test: free, SHBG-bound, and albumin-bound combined. Total testosterone is typically measured in ng/dl, or nanograms per decilitre. Free testosterone is the measurement of — you got it — free testosterone (which often includes albumin-bound testosterone as well because it can easily convert to free T). Free T is typically measured in picograms per milliliter. As we’ll discuss later in this post, because free testosterone makes up such a tiny, tiny percentage of your total T, it’s really hard to measure accurately. So, when you see research on normal testosterone levels, it usuallyfocuses on total testosterone. Consequently, most of the numbers in this post will be about total T levels. With that said, I do include some references to research that indicates what average and optimal free testosterone levels are. What’s a “Normal” Testosterone Level? When you go to get tested for testosterone, the lab will often show you what’s considered the “normal” range among patients who have tested with that particular lab. It’s called the For example, LabCorp (the lab I used to test my T levels here in Tulsa, OK) shows a reference range of 348 – 1197 ng/dl (nanograms per decilitre) for total testosterone levels. According to this reference range, my total testosterone level of 383 ng/dl at the beginning of my experiment would mean my total T levels were — barely — within the normal range. Here’s the problem. That reference range consists of a wide variety of men who tested with LabCorp: 80-year-old men and 20-year-old men; obese men and super fit men; men with pituitarygland problems and men with glands that work like champs. Sure, my 383 ng/dl was considered normal, but normal compared to whom? An 80-year-old man with Type 2 diabetes? The fact that reference ranges don’t break patients down by age or health status explains why a 30-year-old man can go to his doctor with the symptoms of low T, only to be told that his T levels are fine because they’re within the “normal” range. If you’re 30 (or even 50), but have the same testosterone level as an 8o-year-old, diabetic man, your doc may say you’re okay, but you’re still not going to feel good. Plain and simple. What’s interesting is that for many years, the bottom number of the reference range for T levels at many medical labs was much lower. For example, up until last year, LabCorp’s reference range for testosterone was 249-836 ng/dl. You could have had a testosterone level of 250 (which is super low) and still be told by your doctor that you were normal. All this is to say that the “normal” levelsput out there by doctors and labs aren’t all that useful. Average Testosterone Levels by Age When determining what’s considered a normal testosterone level, it’s best to look at what the reference range is for men your age. Researchers have known for years that T levels typically drop by about 1% every year after you hit your mid-30s. So if you’re 35, comparing yourself to a bunch of 80-year-old men isn’t very useful because they likely have really low T levels. Unfortunately, many labs don’t break down reference ranges by age. However, studies have been done in which researchers do just that. Below, I include the results from two such studies. Measurements in Conventional Units (ng/dl), SHBG in (nmol/L) Age # Subjects Total Test. Stand. Dev. Free Test. Stand. Dev. SHBG Stand. Dev. 25-34 45 617 170 12.3 2.8 35.5 8.8 35-44 22 668 212 10.3 1.2 40.1 7.9 45-54 23 606 213 9.1 2.2 44.6 8.2 55-64 43 562 195 8.3 2.1 45.5 8.8 65-74 47 524 197 6.9 2.3 48.7 14.2 75-84 48 471 169 6.0 2.3 51.0 22.7measurement. The problem is that , which is why endocrinologists typically don’t use saliva or urine samples when diagnosing low testosterone levels. Instead they use blood serum tests. While blood tests are much more accurate and sensitive than saliva or urine tests, they’re also much more expensive — blood tests for total and free testosterone can set you back $130. Because I wanted the most accurate results, I went with the blood serum testing. What I didn’t know before I got tested was that there are different kinds of testosterone blood tests, some more accurate than others. As I mentioned at the beginning of the post, there isn’t much standardization amongst labs when it comes to testing. Some labs use one method, while another lab will use another test. I later learned that the blood test I used to measure my total testosterone for my experiment wasn’t the most accurate on the market and wasn’t what the CDC is recommending labs use in their goal to standardize hormone testing.(I tested myself a month after my 90-day experiment with the blood test the CDC recommends. I’ll share my results in a bit.) I also learned that measuring free testosterone is pretty dang hard and that most free T measurements that labs give are typically just estimates. Below I share what I learned about the confusing world of testosterone blood tests. Blood Tests for Total Testosterone ECLIA Method. When I tested myself for total testosterone for my experiment, the method the lab used was ECLIA, short for Electrochemiluminescent Immunoassay. It’s a fast and affordable method to measure total testosterone in your blood. Many labs use this method because it’s automatic and doesn’t require too much work on a lab technician’s part. However, some studies have shown that values obtained with ECLIA are significantly higher compared to the more reliable LC/MS method. Which brings me to… LC/MS Method. LC/MS is short for liquid chromatography-mass spectrometry. It’s considered the goldstandard method by many researchers in measuring small molecules. Its accuracy and consistency is why the CDC is recommending LC/MS to be the standard method used when testing total testosterone. Because LC/MS is more sensitive than ECLIA, doctors typically use this method when testing patients with really low testosterone levels, such as women and children. While it’s more accurate and sensitive, the LC/MS method is more expensive than ECLIA. And it takes a bit longer to get your results. A month after my 90-day experiment, I got tested again, but this time using the LC/MS method. My total testosterone level using this method was 826.9 ng/dl. Meaning my T levels increased even more since starting my testosterone changes. You’ll have to make the call on which method you go with. If you don’t think you have extremely low T, ECLIA will work just fine. Just know that most researchers see LC/MS as the method that produces the most accurate and consistent results. Labs often offer bothECLIA and LC/MS tests. Later on, I’ll share where you can get tested using either method. Blood Tests for Measuring Free Testosterone Reading about the myriad of ways to measure free testosterone has nearly put me in the nut house. It’s confusing. The problem that labs face is that there is so little free testosterone in our body, it’s hard to measure directly. Below I lay out the methods available right now to measure free T. RIA Direct. It’s cheap, fast, but not very accurate. Recent studies have been calling into question the use of RIA direct methodology to measure free testosterone. Unfortunately, most labs across the country only use RIA direct because of its cost effectiveness. LabCorp, the lab I used, only measures free T using RIA direct. Despite the criticisms levied at RIA direct tests, many researchers believe it’s an adequate method for routine tests. Equilibrium Ultrafiltration. Many in the field of endocrinology argue that equilibrium ultrafiltration is a superior andmore accurate testing method to RIA direct. The problem is that many commercial labs don’t offer the method because it’s so time consuming and requires well-trained technicians. If you can find a lab that uses equilibrium ultrafiltration, expect to spend a bit more than you would for a RIA direct. Calculated free testosterone. Instead of directly measuring free testosterone in your blood, . The problem with this method is that 1) it’s not very accurate and 2) it requires you to pay for three different tests: albumin, SHBG, and total testosterone. This can get pretty expensive, pretty fast. As you can see, you have a variety of options when getting tested for T levels. My recommendation is to try to get your total testosterone number using the LC/MS method and use whatever method is available and cost effective to measure free testosterone. Of course, I’m just a guy who writes a blog about manliness, so take that recommendation with a grain of salt. Where to Get Tested for TestosteroneAlright, so you might be asking your computer screen, “Where do I get tested?” If you’re suffering symptoms of low testosterone, ask your doctor to order a blood test for you. Insurance might cover it. If you’re just curious about your T levels, you actually don’t need a doctor’s order. You can sign-up for a test yourself. Here’s how: Order the test. You’ll need to order a blood test using a website that sells blood tests to consumers. No, you don’t send the website a blood sample. These sites contract with labs across the country to draw blood. They basically act as a middleman.Here are the sites I used to buy my tests: . You can order a . Just be aware the methods that Health Testing Center will request are ECLIA for total testosterone and RIA direct for free testosterone. . You can order. They say you can order an equilibrium ultrafiltration free testosterone test, but when I got my lab results back, it showed that the direct method was used. I’m still looking into that, but wantedto give you the heads up. You can also order albumin and SHBG tests from both Health Testing Centers and Request a Test so you can use the calculation method to figure out your free testosterone levels. Go to a local lab. After you pay for your blood test, you’ll get an email from the website with your order information. You’ll also be told which lab you need to visit in your area to have the test done. Both Health Testing Centers and Request a Test sent me to . If you’ve ever applied for a job that requires a drug test, you’ve probably been to LabCorp yourself, as they are a national company. Get blood drawn. A nice nurse will draw some blood samples. The whole process takes less than 2 minutes. It’s best to get your blood drawn first thing in the morning, as T levels are at their highest in the morning and steadily decline throughout the day. Get your results. Two or three days later, you’ll get an email from the lab with your results. Test more than once. Because testosterone levelsare sensitive to a whole host of environmental factors, it’s important to get tested more than once when diagnosing low T. You could have below average T levels one week, but slightly above average the next. This is particularly important if your doctor is considering putting you on testosterone replacement therapy. You don’t want him to make the decision from a single test! Conclusion Whoo, that was a lot of info. If you feel a little lost, here’s a crib sheet: Don’t use lab reference numbers to determine if your T is low. They’re not usually accurate. Use the charts above for your specific age range. Take a blood test to determine your total T levels. You can get this blood test at the doctor, or by signing up online and going to a local lab. Make sure to get tested in the morning! If you can, take the LC/MS test to measure your total T — it’s the most accurate. If that’s not available, the ECLIA test will work okay. To find your free T, try to use the Equilibrium Ultrafiltrationtest — it’s the most accurate. If that method isn’t available, the RIA Direct test will work okay. I hope this information was useful. I definitely learned a lot in the process. Again, if anybody sees any corrections that need to be made or if I missed anything, please offer your constructive and friendly feedback. Tomorrow we’ll cover that long awaited subject : how to boost your testosterone naturally. Testosterone Week Series: Tags:
