7 Blood Tests To Ask For At Your Annual Physical + How To Get Them Covered By Insurance

If you're remotely health-conscious, you probably get an annual physical during which your doctor asks how you've been feeling, does a brief exam, and occasionally (but not always) orders some blood work. Maybe she spouts off the names of a couple of lab tests she's ordering, like a CBC or CMP—but rarely does anyone explain what exactly these tests are looking for. So you get your blood drawn, get a call a few days later that things came back "normal," and you don't really think much about it until next year. 

And again, that's if your doctor calls for any blood work at all. I actually went from age 25 to 30 with zero labs from my general practitioner, even though I have a family history of heart disease and high cholesterol. 

On the other end of the spectrum, though, you know there are functional and integrative docs out there who tout all sorts of medical tests (from inflammatory markers to food sensitivities) that supposedly help spot problems early on and offer intel on how you might tweak your diet and lifestyle to optimize your health. But not everyone has access to this type of practitioner, and not all of these tests are covered by insurance. 

So then the question becomes: What's a happy medium between bare-bones and borderline excessive lab testing? If you're seriously proactive about optimizing your health and preventing issues, what are the key tests to consider getting done semi-regularly that pretty much any doctor can order and that will most likely be covered by insurance? 

A complete blood count (CBC) is one of those basic tests that's often included as part of an annual checkup—or that will be if you ask for it. It measures different features of your blood, including red blood cells, white blood cells, platelets, hemoglobin, and hematocrit. 

"A CBC will find anemia, which is common among menstruating women, and it's also a screening test for immune system issues and different types of cancer—blood cancers that can happen in young people," says Chloe Godwin-Gorga, M.D., an integrative primary care physician. "So if you get a wonky CBC, it's a reason to be more thoroughly evaluated. That's why it's a really good basic test." 

Who should get it? All adults.

Another basic but goody is a comprehensive metabolic panel (CMP), which reveals information about your overall metabolism, including kidney and liver function and type 2 diabetes risk.

It typically includes a measure of your fasting blood glucose, which may not be the best test for predicting diabetes risk or blood sugar imbalances but gives you a general idea (pro tip: A fasting blood glucose of less than 100 mg/dL is considered "normal," but most functional docs would like to see that number at around 70 or 80 mg/dL, says Heinz). It also looks at electrolytes like sodium, calcium, and potassium, which can indicate whether you're dehydrated, and it's a screening test for your liver and kidney function.

Who should get it? All adults.

As mentioned above, a fasting blood glucose test (which is typically part of a CMP) isn't always the best indicator of blood sugar dysregulation. According to all of the doctors I spoke with, one of the best ways to get a heads-up about blood sugar issues, insulin resistance, and prediabetes before they manifest as serious health problems is with a hemoglobin A1C test1 (HbA1C). 

An HbA1c test measures the percentage of red blood cells saturated with glucose. The higher your A1C, the higher the estimated average blood glucose. Your HbA1c number is generally considered to correlate to your average blood glucose over two to three months—not just a single day. In addition to diabetes, a high HbA1C marker may also increase your risk of Alzheimer's disease and cancer—potentially making the test a good predictor of overall longevity. 

"Interestingly, in young women, having a high HbA1c is also associated with having polycystic ovaries (or PCOS), which can make it really hard to conceive," says Godwin-Gorga. "So if you're headed in that direction and your periods are a bit irregular, finding out that number can provide the motivation to make changes to your eating and exercise habits that benefit overall fertility and metabolism." Then, you can retest in three to six months to see if you've moved the needle. Ideally, you'll want your HbA1C to be 4 to 5.3, though lower is better.

Who should get it? Preferably all adults, particularly if you're overweight, at increased risk of diabetes, struggling with fertility or symptoms of PCOS, or over age 45.

For a broad picture of heart health, you at least want a standard lipid panel, which is a measure of your HDL ("good") cholesterol, LDL ("bad") cholesterol, and triglycerides. But while this is certainly a good baseline test, especially if you have no heart disease risk factors, many functional and integrative doctors don't believe it goes far enough. That's because, even though high LDL cholesterol has consistently been linked to heart disease, there are still some people with normal or even low LDL levels2 that develop heart disease—so there's more to the story.

Increasingly, integrative doctors, including Gandhi, Amy Shah, M.D., and Kristann Heinz, M.D., R.D., are calling for more advanced lipid panels, like those that include a breakdown of lipoprotein size (cholesterol particle size). Research suggests that looking at numbers of specific particles is more indicative of your risk than simply zeroing in on total or LDL cholesterol. Basically, you want your particles to be big and buoyant, not small and heavy, because then they tend to lodge in the walls of arteries more easily, which can increase your risk of heart attack and stroke.

If your insurance doesn't cover a more advanced lipid panel, you shouldn't stress—but you should look at the numbers on your standard lipid panel more closely. "One of the strongest predictors for preventing heart disease is having a good HDL-to-triglycerides ratio," says Steven Gundry, M.D., cardiologist and functional primary care physician. "So your HDL should be higher than or equal to triglycerides." 

Who should get it? All adults, especially if you have a family history of heart disease or other risk factors.

Thyroid disorders are incredibly common, affecting one in 10 women, and about 60% of people with a thyroid problem are unaware of their condition—and thus, unable to manage it appropriately. Hypothyroidism (or low thyroid function), especially the common autoimmune type called Hashimoto's thyroiditis, is often missed as a hidden cause of fertility problems and pregnancy loss.

This is why nearly every doctor I spoke with recommended some degree of thyroid testing for women (at least a thyroid-stimulating hormone, or TSH, test), and a more comprehensive thyroid panel for women experiencing unexplainable weight gain or loss, chronic fatigue, cold intolerance, hair loss, forgetfulness, constipation, and feeling generally depressed. For these women, Godwin-Gorga likes to run a panel of five tests: TSH, free T4, free T3, reverse T3, and two types of thyroid antibody levels called anti-TPO and anti-thyroglobulin.

TSH alone can miss many cases of Hashimoto's. That's because thyroid function is very erratic (or up and down) in the early stages of this condition—so TSH levels may actually be normal at the time of your test, even if thyroid function is compromised. A more comprehensive panel can spot issues early while they can still be addressed with lifestyle changes.

Who should get it? Monitoring your TSH levels over time is a good idea for most women, and a more extensive thyroid panel may be warranted for women with the symptoms above and/or a family history. 

Another go-to test among functional docs, particularly if you're experiencing fatigue, is a 25-hydroxy vitamin D blood test. "The majority of my patients are actually vitamin D deficient3; that's why it's part of my standard panel of tests," says Gandhi. This can occur for a number of reasons. "Geographically, many of us aren't exposed to enough sun year-round, some people have a genetic mutation so they can't synthesize vitamin D from sunlight, and we're also taught to wear sunscreen." 

Shah echoes this sentiment: "I check vitamin D levels on almost every woman," she says, adding that this vitamin and hormone-precursor plays a key role in immune function and mood. Deficiencies in vitamin D can also be a factor in autoimmune disease and certain cancers.

When it comes to vitamin D levels, keep in mind that a "normal" test result, which is anywhere from 30 to 80 ng/mL, does not necessarily indicate "optimal"—ideally, you want it above 50 ng/mL, says Gandhi. If you're below that, supplementation will likely be necessary.

Who should get it? Most adults, particularly women and those experiencing fatigue and poor mood.

So far, this piece has referenced fatigue and low energy a lot—because, unfortunately, these are pretty common symptoms among U.S. adults, especially women. In addition to thyroid issues and low vitamin D, another potential cause of waning energy levels is low levels of a few key nutrients: iron, ferritin (the stored form of iron), folate, and vitamin B12. Your doctor can test for these separately or all at once on an anemia panel, says Godwin-Gorga.

Low vitamin B12 is common among vegetarians and vegans but can also exist among omnivores due to nutrient malabsorption issues caused by antibiotic overuse, or celiac or Crohn's disease. Folate plays a crucial role in healthy pregnancy and preventing birth defects but often is not screened. And pretty much any menstruating woman has the potential to be low in iron. So, this combo of tests can be pretty revealing—and low levels can be easily remedied. 

"Iron is an interesting one," says Godwin-Gorga. "It affects your thyroid, and if your iron is low, it can present as hypothyroidism. It's so common for women to feel normal once we replenish their iron." And interestingly, even if you're not anemic (which can be tested for with a CBC), you can still be iron deficient—which is why testing for iron and ferritin separately is important. 

Who should get it? People experiencing fatigue, particularly if you're a menstruating woman, or if you follow a plant-based diet. 

One of the biggest issues with medical testing—even if you do manage to get some good tests ordered by your primary care physician—is that you may not know what to do with the results. "I think one of the big lapses in primary care right now is that no doctor is really giving you good feedback on what the numbers mean," says Godwin-Gorga. "It takes them getting abnormal before anyone even says something to you. But there's a lot of room to say, 'Hey, this is not optimal; let’s talk about that.'"

In most cases, you don't need to run a bazillion tests to get a good picture of your health and what you can do to optimize it. Start by doing your homework. Write down any ongoing or new symptoms and a complete family history—then, ask your doctor what tests they think you should get based on this, and have a discussion about some of the specific tests mentioned above if you feel they may be warranted. Also remember, how your labs are interpreted is just as important as getting them done in the first place—and if you want more guidance on what you should do based on your results (in terms of lifestyle changes or further testing), probe your doctor for more details or get a second opinion. And remember, always call your insurance company to ask about coverage!