Introduction
This is a somewhat sad story from early in my internship. Your internship year is when they really try to sort people out. You're often on call every third night and get regularly harassed by anyone with a little more seniority than you in the medical system. Unfortunately, that's almost everyone. Even the janitors feel more senior than you do when you're an intern.
In an effort to expose you to many different areas of medicine, they place you on rotations. Those rotations are usually a month on a different service. Early in my internship year I was on the Internal Medicine Service.
An elderly lady came to the hospital emergency room. At the time of her exam she felt fine and wanted to go home. Her family convinced her to have some screening lab work. In the process of that evaluation they found some red blood cells in her urine. She was sent to the radiology department for a test of her kidneys and had a reaction to the dye that was given to her. That bought her an admission to the hospital.
I saw her almost every day for the next month. At the end of that month I was ready to switch to a surgery rotation. She had unfortunately fallen and had some injuries. Those injuries got her transferred to the surgery department and I continued seeing her every day.
Long story short: she had no medical history and had done quite well at home for 80 years until her family convinced her to come to the emergency room when she didn't feel well.
That story has stuck with me for decades. The problem wasn't the lab work itself. The problem was reacting to a single abnormal finding with no context, no baseline, and no understanding of what was normal for her.
What does "normal" really mean?
How many times are people told that their lab tests are normal?
What does normal mean?
If you understand the way lab tests are reported, the results are placed in large databases, a bell curve is applied, and mathematics are used to determine what's normal and what's abnormal. Normal on paper doesn't always match what your body is trying to tell you. You know you don't feel optimal. The reverse may also be true. You feel fine but the numbers tell a different story.
The broken system rewards speed over pattern recognition. Many of the younger and more recently trained physicians focus on the numbers and don't rely on history and exam. That leaves patients with a task most were never taught. They need to know their own numbers well enough to recognize a shift and insist on a closer look.
When your doctor says your labs are normal, it sounds like a clean bill of health, an "atta boy." Most times it's no cause for alarm. However, normal in laboratory medicine lingo means your results are within a reference range, not necessarily optimal levels or the levels at which you feel great. Normal simply indicates how you compare with everyone else.
Here's how ranges are set: Labs collect results from people they consider to be healthy, remove the outliers, and label the middle 95 percent as normal.
How thinking has shifted during my career
Here's a great example of how thinking has changed over the years. Very few were supplemented with testosterone years ago. Everyone had normal lab values for their age. Then the thinking shifted to recognizing that your level may be normal for a 70-year-old male but half of what a 25-year-old male would display on his lab. Supplementing provided great benefit. Of course, we had to go through years of alarm about what might happen if you had prostate cancer.
Each lab defines normal differently, and there's no national standard. Federal rules ensure accuracy but not uniformity, so a result that appears accurate in one lab may be flagged as incorrect elsewhere.
Studies have shown that the definition of healthy can affect the reporting of lab results, for example if someone is known to have disease.
When the reporting is based on large populations you might guess the effect we're seeing in the U.S. as obesity has become such a prevalent condition. The averages are encompassing many people that aren't healthy. Cholesterol levels are elevated and more common, and therefore more "normal." The same is true for sugar or glucose levels. Many lab ranges haven't been meaningfully updated in decades, meaning that what looks fine today might have generated a warning in the past.
Technology can introduce differences as different labs use different instruments. Each instrument has its own reference range of "normal" values.
Why trends matter more than single results
If your fasting glucose is higher now than the last time you checked, that should be a target for continued inspection. We now have continuous glucose monitors. They were originally developed and marketed for diabetics, but as it's become recognized as an important biomarker for health, more and more people are using those devices to stay tuned into their glucose levels.
Each person's body tends to run on its own unique set of parameters. Most people's blood tests are stable for them and quite unique when taken as a whole.
A fasting glucose level of 95 might be considered healthy for one person, but it signals an early change for someone whose usual level is 80. In general, although your level of 95 might be reported as "normal," the goal of health is a lower fasting morning level.
Trends reveal relationships. Watch the glucose levels over time. If that sugar is climbing you may need a diet modification. Everything is interrelated. If your thyroid function is abnormal your cholesterol levels will likely be affected.
When results are read in isolation, systemic connections can be missed. Anyone can track their lab over time. We can help you get that established.
How to keep up with your labs
A simple spreadsheet or notebook can be your tracking tool. Some of the labs we'll recommend do most of that work for you if you continue to use the same lab. The goal isn't to dig into every number. Track the shifts in your values. We want them to improve.
In the last few years, due to the buying power of large organizations, you can get 100 biomarkers for a couple hundred dollars. Not that many years ago, if ordered separately, that would have been well over a thousand dollars.
Record results on a graph by date. Develop a spreadsheet to keep up with the date of the test and each biomarker. Make a note if something changed, like the lab that did the test.
Code any trend. Highlight or color-code changes.
Keep notes of what you're doing that might change results. Put dates for diet changes, supplement changes, weight changes.
Bring your charts and notes when you meet with your healthcare provider. Be a detective. Try to understand what's working and what isn't.
The standard panels miss important markers
Cholesterol for many years was a crude test that didn't change. Some of the most important numbers weren't routinely checked even though the lab was available. It was more expensive and most insurance wouldn't pay for it.
Routine lab can miss the bigger picture. The old cholesterol test gives numbers for total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, and triglycerides. Lab evaluation for low-density lipoprotein particle (LDL-P) size and apolipoprotein B is more important for assessing heart disease risk.
Doctors may know that better tests exist but they aren't ordering them because they're using orders designed for insurance coverage or billing codes.
Don't be a nuisance if you're guessing
Don't chase every number. I can't tell you how many abnormal labs I've fixed in my career just by repeating the test. Lo and behold, the repeat test came back with a totally different and normal value.
Sometimes too much lab can lead to problems. Remember the story of my 80-year-old lady when I was an intern.
Again, paying attention to trends may be the most important takeaway.
Understanding your results in context
The lab should be interpreted in the context of YOU. What is your usual number? What might warrant a repeat in a month or two? Is it going up or down?
If your lab doesn't keep the trends on a graph, make your own spreadsheet.
Best to choose a lab and stick with them. Quest or Labcorp are good choices. They're huge and many lab packages offered by different entities are processed and run through Quest or Labcorp. Using the same lab takes some of the variability out of the question.
Don't freak out. If you get an out-of-the-ordinary high or low result, that lab, in most cases, should be repeated before action is taken.
Some tests measure critical electrolytes and organ function and they may be more important than other labs you're checking. Sodium, potassium, creatinine, or liver enzymes may be an early warning indicating a need for more immediate attention. Other labs like cholesterol or your Vitamin D level warrant slower approaches.
Think optimal, not "normal." Normal reflects averages, not optimal. Many people feel better with vitamin D levels closer to 50 nanograms per milliliter, even though 30 nanograms per milliliter is considered normal. Many functional medicine providers like to see numbers around 80 or above.
When to ask for a deeper look
Your labs look fine but you don't feel fine. Fatigue, brain fog, emotional or mood changes may indicate an issue. Routine lab may not show a problem but a deeper look may highlight something to track down.
Your numbers are drifting. A steady rise in blood sugar or liver enzymes, or a slow decline in ferritin or vitamin D, can hint at an imbalance long before lab results demonstrate abnormal.
The lab may be incomplete. There are times when you have to keep asking. If you don't feel well the correct test may not have been ordered yet.
There may be a logical reason the lab changed. Many see several specialists and one doctor may have no idea another doctor has you on a new medication that explains the lab change. Show up with your notes and charts.
Some doctors won't have the right perspective. You have to look at the whole picture. Specialists may not focus on systems they don't specialize in. There are times that you need to review what's happening with your primary care physician.
In the end, the numbers are the numbers
You have to learn to pay attention and trust your body. Your regular notes will help you pinpoint trends in how you feel, changes in your bowel movements, your sleep patterns. Those notes are giving you clues.
This is a journey, a marathon and not a sprint. Start and don't get discouraged. Stay at it. The reward is worth the effort.