One of the best ways to monitor your health is through the testing of the most vital of bodily fluids—your blood. Flowing into every nook and cranny of your body, blood carries oxygen and important nutrients and hormones to your cells, as well as transports waste products to the lungs, liver, and kidneys for excretion. Thus, your blood provides a treasure trove of information on the state of your health.
Annual Lab Tests Are a Good Idea
Maybe you already submit to blood tests as part of your annual check-up with your doctor. If you’re generally healthy they may advise everything “looks normal” whether or not you have been complaining of various symptoms.If you’re managing a chronic condition, perhaps your doctor requests more regular testing and monitors your numbers to adjust medication accordingly. Or maybe you’ve been avoiding the doctor and haven’t had any lab work done in a while.
Blood tests are one of the least invasive and most cost-effective tests you can get to be proactive about managing your health. Testing centers are typically easy to find and make an appointment with. In 15 minutes, you can be in and out, having had a few vials of blood drawn in a usually pleasant setting, and be on your way. Results are often available online a week or so later.
Limitations of Normal Ranges
The trick though is in understanding the context of all those numbers and how your results compare to the cited “normal range.” Only then can you begin to glean relevant insights to optimize your health.For starters, even if you test 100 different biomarkers in your blood, it is barely scratching the surface of what is going on inside your infinitely complex body that is constantly working to keep you in balance and functioning well.
A blood test generally measures a moment in time and may be influenced by what you ate the day before, how much you exercised, if you had an argument with your spouse, or how well you slept the previous night. You are an individual. There is no such thing as a perfect score for any element being tested.
The reference values or normal ranges listed on your test results are typically lab-specific and are based on the test results of a subset of the population studied. The range then covers the results for 95 percent of this sample population who are deemed to be healthy. The lowest 2.5 percent and the highest 2.5 percent are considered outliers, with the rest considered normal. So if the health of the sample population is in fact less than optimal, this reduces the standard of what is considered “normal.”
Typical Tests Your Doctor May Order
The biggest use of blood tests is to assist your doctor in making diagnosis and treatment decisions. The pharmaceutical industry relies on biomarker testing to prove its drug is doing what it claims to do better than a placebo.Most drugs are evaluated by their effect on a biomarker rather than their impact on actual health. But as long as we understand the context and limitations of the tests, we can use them to our advantage, helping to inform our priority interventions.
- Metabolic markers—to understand your kidney and liver function, blood sugar level, proteins, and electrolyte balance including your hydration status.
- Complete blood count—looks at your red and white blood cells and platelets, which can indicate an infection, anemia, or blood clotting issues.
- Lipids—will include your LDL (low-density lipoprotein) and HDL (high-density lipoprotein) cholesterol, and your triglycerides (a type of fat stored in your liver).
- Thyroid function—especially for women, specifically your TSH (thyroid-specific hormone) levels indicating potential hypo- or hyperthyroidism, which can affect many aspects of your health including infertility.
- Hemoglobin A1C—especially for those who have a high basic glucose level or who are overweight. It measures the percentage of your blood cells that are saturated with glucose and provides a better measure of your average glucose level over the past two to three months.
- PSA (prostate-specific antigen)—men only. Can indicate problems with the prostate, including cancer, but other factors can also affect PSA levels.
- You are outside of normal ranges and your doctor is proposing pharmaceutical treatment to address it.
- You are inside of normal ranges but are suffering from “unexplained” symptoms.
- Inflammatory markers—C-reactive protein (hs-CRP, the high-sensitivity version) can be used as a general measure of inflammation and risk for cardiovascular disease and depression. Homocysteine is an amino acid that needs certain B vitamins to break down—elevated levels can indicate impaired ability to detox and make neurotransmitters.
- Thyroid detail—beyond the basic TSH score, more accurate tests can measure additional elements such as free T4, total T3, free T3, and reverse T3 to get a better picture of how your thyroid is performing.
- Full hormone panel—such as the DUTCH testing service, which stands for dried urine test for comprehensive hormones—which tests over 24 hours to get a more accurate picture.
- Cancer detection—such as the Galleri test that has been validated to detect early signals of more than 50 types of cancer.
- Pathogen antibodies—including Lyme disease and mold using specialty tests such as those offered by Realtime Laboratories and IGeneX.
- Essential nutrients—such as vitamin D, iron/ferritin, B12, folate (B9), magnesium, and omega-3s.
Understanding Nutrient RDAs
In our modern world of overscheduling, ultra-processed food, insidious technology, and other toxin exposures, so much of what ails us is due to an underlying nutrient deficiency. There are simply inadequate nutrients going into our body to run all the many complex systems that rely on them.It is therefore recommended to include nutrient-level testing in your annual blood work. But make sure you apply a similar level of caution in their interpretation and your response for three main reasons:
1. The “normal” ranges quoted for nutrient tests are usually far too low, given that the vast majority of the U.S. population is deficient, and therefore so is any sample taken to set the ranges. A deficiency in certain nutrients may not immediately present with symptoms so the sample population may be considered healthy subjects but in fact, their nutrient levels are not optimal.
2. It is important to understand that blood levels are not always a good indication of absorption or availability to your cells. Magnesium, for example, is stored in your bones and tissues with only a small amount circulating in the blood. Absorption of one nutrient can also affect another, with low magnesium levels potentially responsible for low potassium or calcium levels as well, emphasizing the need to look at all test results holistically.
3. Another factor to understand when responding to nutrient test results is the recommended daily allowance (RDA) suggestions—more often now quoted in the United States as daily value (DV) requirements for individual nutrients.
The focus was to prevent the occurrence of specific diseases such as scurvy, beri beri, pellagra, and rickets (respectively long-term deficiencies in vitamin C, B1, B3 (niacin), and vitamin D for calcium absorption). They weren’t (and still aren’t) focused on optimal health.
In Conclusion
It can seem a bit overwhelming to synthesize the pros and cons of lab testing, as well as make an informed decision on what tests to undertake and how to interpret the results. As with all aspects of your health, it is a very individual decision and warrants taking the time to research some details rather than ceding responsibility to the professional in a white coat. Standardized guidelines are never a substitute for an informed holistic assessment.8 Key Tips
- Annual blood tests are a good idea. Despite their drawbacks, analyzing your blood can provide important insights.
- You don’t need to go through a doctor. Several direct-to-consumer options are now available without a doctor’s requisition order.
- Nonstandard tests may be helpful particularly if symptomatic. Consider additional testing for better insight, although be aware your insurance plan may not cover them.
- Reference ranges are not always useful. Individual physiology is important, as well as taking a holistic view of all tests and their levels over time.
- Focus on symptoms not just numbers. Context is key. The numbers are just a set of data points. Energy levels, digestion, mental health, and pain for example are important indicators.
- Absorption and interaction of different nutrients may not line up with test numbers. Monitor symptoms for indication of deficiency and take a holistic view.
- A whole food diet is optimal to address nutrient deficiencies and other concerning test results. Make food your first line of defense, opting for nutrient density over convenience.
- If supplementation is required, select quality brands. Nutrient combinations from whole foods (not synthetically made) and a formulation that optimizes absorption are critical.