Many people have the same experience when visiting they’re primary care doctor—they’re told, “All your blood tests look normal. Keep on doing what you’re doing.” Your doctor might even say this despite your physical, mental, or emotional complaints that brought you there in the first place. Not only is this frustrating, it’s not productive for optimizing your health and quality of life. Because what they really mean is, “Keep on doing what you’re doing, until something is so wrong with you that even your basic labs look abnormal.”
Oftentimes in conventional medicine, the incentive to take a proactive rather than reactive approach is missing. Not only do doctors typically lack the time a more proactive and in-depth approach would require, but they’re actually financially incentivized to pursue a bandaid fix that often results in prescribing a potentially unnecessary drug. So it’s no surprise that extensive lab work that gives you a deeper look at your health can feel hard to come by. But in reality, checking-in on basic health markers—like your thyroid function or essential nutrient levels—through annual blood testing can be the key to catching any underlying dysfunction and keeping you healthy. Called biomarkers, these are objective measures that are indicative of what’s going on in your body.
At Parsley Health , we help you heal and transform your health by continuously checking in on you, your health markers, lifestyle, and more through annual blood work. Members’ first visits are 60 minutes, giving your doctor enough time to really get to know you, your habits and health goals. From there, your doctor will order advanced blood testing based on your symptoms and goals to get a deeper picture of your health. This comprehensive blood panel will look at everything from inflammatory markers to allergens, autoimmunity, hormone levels, and more. Your doctor can then use this information to create a personalized health plan, recommending lifestyle or dietary changes, supplements, and, when needed, prescriptions to help you feel your best.
While initial in-depth testing is a great place to start, checking in on your biomarkers with routine blood work will not only help you stay on top of your health and catch issues before they become a problem, but can be a great tool for tracking your progress.
Whether you’re looking to identify and treat an ongoing illness, or just want to optimize and maintain your health, these essential blood tests are a great place to start.
In most primary care offices, if you’re lucky, your doctor will check one or two thyroid markers. Usually, the ones checked are thyroid stimulating hormone (TSH), which creates thyroid hormones T3 and T4 in response to the brain’s signals, and/or total T4, the main form of thyroid hormone that’s circulating in the blood. But these levels don’t really give the full picture of how your thyroid is functioning. At Parsley Health, there are 6 additional thyroid-related values that we routinely check to get a more accurate sense of your thyroid health: Free T4, Total T3, Free T3, Reverse T3, anti TPO Ab and anti Thyroglobulin Ab. If any of these blood test values are not optimal, your doctor can recommend a program to prevent full-blown thyroid dysfunction or disease.
We look for “optimal ranges” as opposed to “normal ranges” of these labs. For example, the normal range for TSH is generally considered 0.2 – 4.5, however, there are studies that show that the body does not function properly when TSH rises above 2.5. A study published in the Journal of Endocrinology and Metabolism in 2010 even showed that the rate of miscarriage in first trimester pregnancy was almost double when the TSH was over 2.5.
Iron, vitamin D, vitamin B12, and magnesium are so important for optimal bodily function, but they’re usually not checked at a routine primary care visit. Many people are deficient in these nutrients for various reasons, so it is imperative that we check these levels and supplement them when they are not optimal. Nutrient deficiency can be responsible for symptoms ranging from fatigue and lethargy to kidney damage, so supplementation with any of these nutrients when people are low can be completely life-altering. I’ve had countless patients tell me how seemingly magical the improvement was in how they felt after taking these supplements when they were deficient.
Again, it’s important that we concern ourselves with getting to optimal range as opposed to normal range. For example, in the case of vitamin D, the normal range can be from 30-100 nmol/l, but optimal range is more like 50-80 nmol/l. Reviews of many scientific studies have shown optimal levels are at least 75 nmol/l in relation to bone mineral density (BMD), lower extremity function, dental health, risk of falls, admission to nursing homes, fractures, cancer prevention , and incident hypertension.
These are two essential blood tests that are typically ordered at a primary care yearly physical and offer a lot of information. They are vital to understanding a person’s electrolyte and hydration status, kidney function, liver function, and blood cell values. These values would also tell us if someone is fighting an acute or chronic infection, has anemia, or clotting issues.
In terms of optimal ranges, when we look at liver enzyme levels that are still considered in normal range, but on the upper end, we can tell that there might be a detoxification or liver inflammation issue that should be addressed right away to prevent further progression of illness. A number of studies have shown that this upper lab limit should be decreased in order to catch liver inflammation early , especially among certain ethnic populations .
Metabolic markers are essential to understanding how a person is processing the macronutrients that they eat. In most primary care visits, a basic lipid panel and glucose level would be done yearly, and some people may also get a hemoglobin A1c. For patients at higher risk of heart disease, we run extensive lipid panels as opposed to a basic one. This can help us better determine whether there is actually increased heart disease risk from their cholesterol levels or not. Many times people are told that they have high cholesterol levels when they are not actually a risk.
The HbA1c is a measurement of blood glucose level average over the past 90 days or so, but it is also a relative marker of oxidation in the body. Having elevated blood glucose levels creates oxidation, or damage to proteins, DNA, and tissues in our bodies over time, so this is an imperative value to know and optimize.
Elevations in any of these levels are a sign that your body is not processing glucose properly, which can increase your risk for diabetes, heart disease, cancer, and Alzheimer’s disease. One study published in the Journal of Neurology in 2005 showed that even if your HbA1c is considered in normal range, every increase by 0.1 will increase the rate at which your brain shrinks in size per year. This is why being advised on how to reach optimal range is so much more important than simply saying you’re in normal range.
Inflammatory markers are almost never checked at a routine primary care visit. hsCRP is an inflammatory marker which can indicate your general inflammatory status. Even mild increases in hsCRP are associated with increased risk of things like cardiac events or depression . An elevation can tell us that there is an inflammatory response happening in the body that should be addressed, whether it be from physical trauma, emotional stress, oxidative stress, environmental toxicity, allergy, sedentary lifestyle, or food sensitivities .
Homocysteine is an amino acid that requires methylated-vitamin B12 and folate to be cleared. Elevations in this level can indicate a multitude of things like stroke and heart disease risk, B vitamin status, ability to methylate, ability to detox and make neurotransmitters, and ability to turn off cancer genes. It’s an important marker that we try to get into optimal range by supplementing with methyl-B vitamins when necessary.
While getting these annual blood tests is a great place to start when it comes to optimizing your health, having doctors and health coaches you trust that can help you interpret the information into an actionable plan is what will really make a difference in your health. Whether you have a chronic disease you want to resolve or you just want to live a healthier lifestyle, these essential blood tests will give you and your doctor the tools needed to get started.