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Gersten Alt. Med.

How to Interpret Lab Work

One of the ways to understand conventional and alternative medicine has to do with how lab work is ordered and interpreted. Conventional medicine is best utilized in the treatment of emergencies, whether physical trauma, medical, surgical, or psychiatric emergencies. Conventional medicine also can play a critical role in birth as well as end-of-life care. If you’ve been in a car accident, you won’t be looking for herbs, potent nutritional products or aromatherapy. You’ll be in an emergency room, wanting the best ER doc, and if needed, a top surgeon.

Alternative medicine holds more real promise for the treatment of chronic health conditions. Most alternative therapies aim to find the underlying causes of illness, and treat them. In nutritional medicine, many of the underlying causes of illness involve problems with cellular biochemistry. Conventional medicine generally brings quicker relief of chronic symptoms without a deep understanding of underlying causes (whether physical, mental, or spiritual). Both conventional and many alternative practitioners make their decisions based on the lab tests they order as well as how they interpret the lab results.

Optimal vs. Normal

There are three areas we’ll address regarding evaluating lab data: 1) Normal versus optimal lab results, 2) Incorrect reference ranges, and 3) Lab results that reflect more than what is obvious.

Conventional medicine, in evaluating lab work, looks for what is in the “normal range.” Alternative medicine pays close attention to the normal range, but is as concerned with what is in the “optimal range.” The “normal” range is determined by analysis of very large numbers of healthy young people. The “optimal” range is the lab value best suited to your individual health.

When your blood is drawn for any kind of test, the results will come back showing: 1) the normal range and 2) results that are not in the normal range. The lab printout places normal results and those out of range in two different columns, making it easy for the clinician to quickly identify abnormalities. In this article, you’ll read about a number of lab values. I won’t describe each value completely, as each value in a lab print out will say things like “4 mg/DL.” That’s 4 milligrams per deciliter.

Let me illustrate the importance of paying attention to results that fall into the normal range, but that are far from optimal. Several years ago I evaluated a 50-year-old man who had recently been evaluated by an endocrinologist. In evaluating adrenal function, a blood test for cortisol, one of the two most important adrenal stress hormones, was ordered. The normal range for blood cortisol is 5–100. My patient had tested at exactly 5, which is “normal.” Because the lab test said he was normal, he was not treated for an adrenal problem. Had the result been 4.9, the lab printout would have indicated that the man was deficient in cortisol and the number 4.9 would have appeared in the “abnormal” column. It is most likely that his endocrinologist, looking at 4.9, would have said, “You’ve got a serious problem with cortisol. It’s very low and we need to treat it.”

In conventional medicine doctors don’t generally treat anything that is “normal.” In interpreting a complicated test like amino acid analysis, which has about 40 sub-tests, there will usually be amino acids that are grossly deficient, some that are slightly above the low end of normal (for example 5.1 for cortisol), those that are right in the middle of the normal range, those at the high end of normal, and those in the abnormally high range. Failure to take into account both normal and optimal values, including low normal and high normal results, will lead to an incomplete and incorrect interpretation of the data.

Incorrect Reference Range

The reference ranges used by standard laboratories represent data gathered from average populations. If you’re 40 or older, you are not average, but so-called normal reference ranges are still used. Most of these normal ranges were determined from healthy young people. One area where this poses a major problem is with hormones, where normal values are determined from people under 30. If you are 50 or 60, your testosterone, DHEA (a major adrenal stress hormone), and testosterone are likely to be deficient, while estrogen and insulin are likely to be elevated. But, because the reference ranges are so wide, all four of these may fall into the normal range, even though they may not be optimal. The fact is that whether a man is 25 or 60, he is going to be healthier and more vital if testosterone, DHEA and other hormones are closer to what they were at a younger age. In conventional medical thinking, if you’re low normal on a lab test, you’re still normal—even if those low lab values reflect a genuine need for hormone replacement.

Here’s a short list of normal and optimal lab ranges developed by Life Extension for a 60-year-old man. 1) DHEA normal range: 42–290. Optimal range: 500–640, 2) free testosterone normal range: 6.6–18.1. Optimal range: 15–22, and 3) Insulin normal range: 6–27. Optimal range is less than 5. Understanding the fallacy of the insulin reference range could save your or a loved one’s life. Insulin is a recognized contributor to prostate cancer. A “normal” insulin value of 12 doubles the cancer risk. A value of 15 quadruples the risk of prostate cancer. Note that Life Extension’s recommended upper limit of insulin is 5!

From now on, when your doctor is reviewing lab data with you, remember that your optimal value is probably close to the middle of a reference range. Take some time and look at the reference range of each test. Notice if a lab value is at the low or high normal end of the spectrum. Those values are not optimal. Consider DHEA’s normal range of 42–290. The span of that reference range is so large as to be somewhat absurd. I do not consider 42 to be close to optimal.

I believe that paying attention to optimal lab values is part of a holistic approach, which looks at the very big picture (everything in a person’s life). The principle of understanding normal and optimal lab values applies to more than certain rare nutritional tests. Many patients, when coming in for their first consultation, bring in past lab work, including standard chem panels. I review that data, looking for any normal values that are at the very low or high end of the reference range. The normal range of fasting blood glucose is 70–100. If the result was 99, I’ll pay attention, even though it is normal. I might want to order a blood sugar 2 hours after breakfast (postprandial glucose) to learn more about blood sugar chemistry. And I’ll ask questions about a family history of blood sugar problems.

“Normal” Changes Over Time

Over the course of modern medicine, normal values have been determined for countless lab tests. But don’t think that those reference ranges are eternally true. In the 1960’s, the upper end of the reference range for cholesterol was 300. 300 was considered to be normal. As research data accumulated about cholesterol and the risk of heart attack, the upper end of normal came down to 200. When the high normal value was 300, it was believed to be normal for many men to have fatal heart attacks at a young age. Now we know that a cholesterol value of 300 is a heart risk factor. As we live longer, the “youthful” normal ranges become more and more inaccurate.

Information Hidden in Lab Data

A routine chem panel (comprehensive metabolic panel) evaluates kidney function, liver function, lipid (fat) levels, glucose, electrolyte and fluid balance, along with a complete blood count (CBC). Diagnosing and treating obvious problems found in a chem panel can be life saving. Beyond the obvious diagnoses a doctor makes, there are some hidden gems best understood by naturopaths and nutritional medical doctors.

The CBC tests for the complete red blood cell count, the white blood cell count, platelets, and white blood cell differential. The WBC differential provides a breakdown of the various kinds of white blood cells. One component in the WBC differential is basophil cells. These are associated with inflammation, production of serotonin and the anticoagulants heparin. Basophils also produce histamine, which is associated with allergy, among other things.

In interpreting a chem panel and basophil levels, a doctor rarely is thinking about brain function. While he’ll think about allergy when observing high levels of basophils, he is unlikely to wonder if that elevated lab value might relate to mental emotional problems. Dr. Carl Pfeiffer, Ph.D., M.D, one of the pioneers in orthomolecular medicine, studied the role of histamine in mental illness. Both deficient and elevated histamine are associated with schizophrenia and bipolar illness as well as anxiety, depression, and insomnia. Looking at the basophil count is an interesting and quick way to gain important information about brain/mind function.

For most people over 40 regular checkups and lab work can provide valuable information that a single test can miss. Let’s illustrate by examining the hematocrit, which is the percent of whole blood that consists of red blood cells. The normal adult female range is 36–46 percent and the normal adult male range is 41–53 percent. Let’s say we’re talking about a 40-year-old woman whose hematocrit is 37. That’s normal, and if there are no previous tests to compare, a doctor could consider that to be normal. But, if her hematocrit was 45 five years ago, 40 two years ago, and now 37, we can quickly see that, while all three values are within the normal range, her hematocrit is clearly on the decline. Knowing her hematocrit value over several years helps the clinician to know that this woman is anemic (low hematocrit) and headed in the wrong direction.

By understanding the difference between normal and optimal lab values, you can gain vital information about your health. Take a look at your lab work. Check to see if any of the tests in the normal range are low normal or high normal. When we look at “normal” and “optimal” lab values, we have a more complete understanding. Then, if you have had the same lab test in the past, compare the values to see if that particular test is stable, or if it is worsening over time. Lastly, now that you have more information about understanding lab tests, don’t hesitate to ask your doctor for greater clarification. In this age of time-crunched managed care, a 15-minute doctor visit is common. Your doctor probably understands a great deal more about your lab work than he has time to share. He will share what he believes to be critical right now, but may not go into detail about the subtleties. So ask! It might take a few more minutes of your doctor’s time, which is unlikely to be a problem for him. Don’t leave the doctor’s office wishing you had asked a question.

David Gersten, M.D. practices Nutritional Medicine and Integrative Psychiatry out of his Encinitas office and can be reached at 760-633-3063. Please feel free to access 1,000 online pages about holistic health, amino acids, and nutritional therapy at and