Function Health vs Traditional Blood Work: What Standard Labs Miss

Quick answer: When weighing function health vs traditional blood work, the gap comes down to scope: traditional blood work ordered at a routine physical typically covers 20 to 30 biomarkers across a CBC, comprehensive metabolic panel, and a basic lipid panel, while Function Health and comparable membership services run 100 or more biomarkers, adding thyroid depth (free T3, reverse T3), sex hormones, advanced lipid fractions, nutrient levels, inflammatory markers, and metabolic health signals that standard labs skip entirely. The practical difference is not just quantity: the missing markers are often the ones that flag problems 5 to 10 years before symptoms, which is exactly the window where lifestyle changes work.

What does standard blood work actually cover?

A routine annual physical in the US typically triggers three orders: a complete blood count (CBC), a comprehensive metabolic panel (CMP), and a basic lipid panel. Together those cover roughly 20 to 28 individual values. The CBC tells you whether red cells, white cells, and platelets are in normal range. The CMP checks kidney function (creatinine, BUN), liver enzymes (ALT, AST, ALP), electrolytes, blood glucose, and total protein. The lipid panel returns total cholesterol, LDL, HDL, and triglycerides.

Some internists also add TSH if you mention fatigue, hemoglobin A1c if you are over 45 or have risk factors, and occasionally a PSA for men over 50. That is roughly it. The entire draw takes one tube. Results come back flagged only if they fall outside the population reference range, which is calibrated to the average sick American, not an optimal healthy adult.

What you will not see on a standard order: free T3, free T4, reverse T3, cortisol, DHEA-S, testosterone (free or total for most women, and total only for many men), estradiol, LDL particle number, ApoB, Lp(a), homocysteine, ferritin beyond a flag for severe anemia, vitamin D, vitamin B12 serum levels, magnesium, omega-3 index, insulin (fasting), HOMA-IR, uric acid, or any marker of oxidative stress. These are not exotic. Most of them have been in clinical use for decades. They just are not bundled into a routine order.

Which biomarkers are not in a normal blood test?

The gap between a standard panel and a comprehensive one falls into five categories, each representing a domain where the standard order gives you one signal when you need five.

Thyroid: one number versus the full picture

Standard labs check TSH, period. TSH is a pituitary signal, not a thyroid output. You can have normal TSH and low free T3 (the active hormone your cells actually use), elevated reverse T3 (a blocking metabolite), or thyroid antibodies (TPO and anti-thyroglobulin) indicating autoimmune Hashimoto’s. A complete thyroid panel adds free T3, free T4, reverse T3, TPO antibodies, and anti-thyroglobulin antibodies. Missing those is how someone spends two years feeling exhausted with a normal TSH and never gets an answer.

Hormones: a single total where you need context

For men, primary care labs typically return total testosterone if ordered at all, and often only if you ask. For women, hormones are rarely tested outside of fertility workups. A comprehensive panel adds free testosterone (the bioavailable fraction), sex hormone binding globulin (SHBG, which controls how much free testosterone you actually have), LH, FSH, estradiol, progesterone, DHEA-S, and cortisol. Each one tells a different part of the story. SHBG alone explains why two men with identical total testosterone can have wildly different energy and libido.

Cardiovascular risk: total cholesterol versus particle physics

A standard lipid panel gives you total cholesterol, LDL-C (calculated, not measured), HDL, and triglycerides. LDL-C is the least useful cardiovascular risk predictor in that list. What matters more: ApoB (the protein that coats every atherogenic particle, including small dense LDL and VLDL), Lp(a) (a genetically determined particle elevated in roughly 20 percent of Americans that dramatically increases heart attack risk and is invisible on a standard panel), and LDL particle number (LDL-P), which can be high even when calculated LDL-C looks fine. Homocysteine adds another layer: elevated levels damage vessel walls and are correctable with B vitamins, but standard labs never check it.

Metabolic health: A1c alone misses early dysfunction

A1c reflects average blood glucose over three months and will not go abnormal until you are well into prediabetes territory. Fasting insulin tells you about insulin resistance years before glucose rises. HOMA-IR (calculated from fasting glucose and fasting insulin together) quantifies that resistance. Uric acid tracks purine metabolism and correlates with metabolic syndrome risk. These four together paint a picture of where your glucose regulation is heading, not just where it is today.

Nutrients and inflammation: the things standard labs almost never check

Vitamin D (25-OH) is clinically relevant for immune function, bone density, and mood, and deficiency affects an estimated 42 percent of US adults. Standard labs do not include it unless specifically ordered. Same story for ferritin (a precision iron storage marker, not just the flag-level anemia screen), vitamin B12 serum levels, magnesium (RBC magnesium is more accurate than serum), and omega-3 index. High-sensitivity CRP (hs-CRP) gives you a systemic inflammation signal that total CRP misses at low levels. These are not premium biomarkers. They are foundational, cheap to run, and routinely absent from a standard annual draw.

How does Function Health compare to a standard panel, head to head?

Function Health runs over 100 biomarkers across more than 60 tests per draw and includes two full draws per year in its annual membership. The panels it covers that a standard workup skips entirely include: complete thyroid panel (all five markers), full hormone panel for both sexes, ApoB, Lp(a), LDL-P, homocysteine, fasting insulin, HOMA-IR, uric acid, hs-CRP, ferritin (precise, not just flag-level), vitamin D, B12, B9 (folate), magnesium, zinc, omega-3 index, DHEA-S, IGF-1 (a growth hormone surrogate), and more depending on the version. You can read the specifics in a detailed function health review that covers exactly what comes in each draw.

The standard workup catches flagrant disease. The comprehensive panel is built to catch drift. Drift is the slow, years-long movement of a biomarker from optimal toward abnormal before it crosses the clinical threshold. By the time TSH flags, thyroid function may have been compromised for years. By the time A1c hits 5.7, fasting insulin may have been elevated for a decade. The gap between the two approaches is essentially the gap between disease management and prevention.

Category	Standard Annual Labs	Function Health / Comprehensive Panel
Thyroid	TSH only	TSH, free T3, free T4, reverse T3, TPO Ab, anti-TG Ab
Cardiovascular	Total cholesterol, LDL-C (calc), HDL, triglycerides	Above + ApoB, Lp(a), LDL-P, homocysteine, hs-CRP
Metabolic	Fasting glucose, A1c (sometimes)	Above + fasting insulin, HOMA-IR, uric acid
Hormones (men)	Total testosterone (if ordered)	Total + free testosterone, SHBG, LH, FSH, estradiol, DHEA-S, cortisol
Hormones (women)	Rarely tested outside fertility	Estradiol, progesterone, free + total testosterone, SHBG, LH, FSH, DHEA-S, cortisol
Nutrients	Not included	Vitamin D, B12, folate, magnesium, zinc, ferritin, omega-3 index
Inflammation	Not included	hs-CRP, fibrinogen (varies by draw)
Total biomarkers	~20 to 28	100+

What does this cost, and is it worth the difference?

If you tried to replicate the Function Health panel by ordering individual tests through Quest or Labcorp out of pocket, you would spend between $400 and $900 for a single draw, depending on which panels you chose and which lab you used. The thyroid antibody panel alone runs $80 to $120 at cash prices. ApoB plus Lp(a) adds another $60 to $100. A full hormone panel for a man or woman adds $150 to $250. Vitamin D, B12, and folate together run $30 to $60. That is before the lipid subfraction panel (NMR LDL-P is typically $130 to $200 out of pocket).

Function Health charges about $499 per year, which includes two draws. You can see the full pricing breakdown in a function health cost guide that also covers what is included, what costs extra, and when the membership makes financial sense. The per-draw cost works out to roughly $250, which is below what most people would spend assembling the same panel piecemeal, and each result comes with physician review.

If your insurance covers a standard annual panel, you are not saving money by switching entirely to a membership service. The smarter play is to let insurance cover the standard draw and use a membership to fill the gaps. Most of the advanced biomarkers (ApoB, Lp(a), thyroid antibodies, hormone panels, nutrients) are not covered by insurance for asymptomatic patients, so you would be paying cash either way.

HSA and FSA accounts can cover both Function Health and Superpower membership costs as qualified medical expenses, which effectively gives you a 22 to 37 percent discount depending on your tax bracket. Read the details in the section on HSA and FSA eligibility for these services.

Who should prioritize a comprehensive panel over standard blood work?

Standard labs are fine for catching acute disease. They are not fine for someone actively trying to optimize health, manage a slow-moving condition, or understand why they feel off despite normal results. The people who get the most from a comprehensive panel fall into predictable groups.

Anyone over 35 with unexplained fatigue, brain fog, weight gain, or poor recovery from exercise is a strong candidate. Those symptoms map onto the exact biomarkers a standard panel misses: free T3, reverse T3, fasting insulin, DHEA-S, and vitamin D. A normal TSH and normal CBC does not rule any of those out.

People with a family history of early heart disease need Lp(a) and ApoB, full stop. Lp(a) is genetic, unaffected by diet or exercise, and the only way to know yours is to test it. One in five Americans walks around with an elevated Lp(a) that does not show up on a standard lipid panel, and their cardiologist may have never checked it.

Anyone who has gone through a major hormonal transition, including perimenopause, post-menopause, or andropause, needs the full hormone panel, not a single estradiol or total testosterone number. The ratio between hormones, SHBG binding, and adrenal output (DHEA-S) matters as much as any individual value.

Athletes and people training hard are often surprised that their “excellent” standard labs mask low ferritin, low vitamin D, low magnesium, or a suppressed free T3 from caloric restriction. These are common and correctable, and a standard panel will never find them.

What people get wrong about comprehensive panels

The most common misconception is that more biomarkers means more anxiety. The opposite tends to be true. Ambiguous symptoms with normal standard labs generate far more anxiety than having 100 clear numbers, most of which are in range, and three that need attention. Precision replaces guessing.

The second misconception is that out-of-range means diseased. A comprehensive panel uses optimal ranges in addition to standard clinical ranges. A vitamin D of 22 ng/mL is technically in the broad normal reference range at most labs (which is 20 to 100 ng/mL) but meaningfully suboptimal for immune function and bone density. Knowing that gives you something to fix before it becomes a clinical problem.

The third misconception is that a primary care doctor will act on these results. Most will not, because they are trained to treat disease, not to optimize. That is not a criticism; it is a scope of practice issue. If you are using a comprehensive panel for optimization purposes, you need a clinician who reads those values the same way: in context, over time, with an eye toward trends rather than single-point flags. This is why the physician review built into services like Function Health or Superpower is not a marketing feature. It is the interface that makes the data useful.

For a side-by-side look at how different membership services compare on depth and price, the function health vs 10x health and function health vs empirical health comparisons cover two very different ends of the market.

Can you build a comprehensive panel from standard labs yourself?

Yes, and it is worth knowing how. Direct-to-consumer lab services let you order your own blood work in most US states without a physician order. Quest Diagnostics has a consumer portal (QuestDirect), Labcorp has LabCorp OnDemand, and third-party services like Ulta Lab Tests, Walk-In Lab, and Any Lab Test Now act as brokers that let you pick individual panels at cash prices.

The practical limitation is assembly. Picking the right combination of panels, interpreting results without clinical context, and tracking trends over years is time-consuming. You will also pay retail cash prices, which adds up fast. The ApoB panel alone through most cash portals runs $40 to $80. Add Lp(a), a full hormone panel, complete thyroid, all six nutrients, and you are at $350 to $600 per draw before you have even looked at the results.

Membership services exist because most people, even educated health-focused ones, do not want to manage a 30-line test order. They want a single draw, a comprehensive result, and someone with clinical training who can contextualize what it means. If you are comfortable doing the research and assembly yourself, the DIY route works. If you are not, a membership is usually cheaper per biomarker and considerably less friction.

FAQ

What is the difference between a CBC and a comprehensive metabolic panel?

A CBC (complete blood count) measures the cellular components of blood: red blood cells, white blood cells, platelets, hemoglobin, and hematocrit. A CMP (comprehensive metabolic panel) focuses on organ function and chemistry: kidney markers, liver enzymes, electrolytes, glucose, and total protein. Most annual physicals include both, giving you roughly 20 to 28 combined values. They are complementary, not overlapping.

Does standard blood work check hormones?

For most patients, no. A routine annual panel does not include testosterone, estradiol, progesterone, DHEA-S, cortisol, LH, FSH, or SHBG. Thyroid is limited to TSH. Hormones are typically only ordered if you report symptoms, are being treated for a hormone-related condition, or specifically request them. Comprehensive panels include the full hormone suite as standard.

What is ApoB and why does it matter more than LDL?

ApoB is a protein that sits on the surface of every atherogenic particle in your blood, including LDL, VLDL, and IDL. One ApoB equals one particle. LDL-C, by contrast, measures the cholesterol content inside LDL particles, which varies considerably by particle size. You can have normal LDL-C with a high ApoB if your particles are small and dense, which is the more dangerous pattern. Most cardiologists focused on primary prevention now consider ApoB the superior risk metric, but standard labs do not include it by default.

Is Lp(a) worth testing if I have no symptoms?

Yes, especially once. Lp(a) is almost entirely genetically determined and does not change meaningfully with lifestyle. It is an independent risk factor for heart attack and stroke that is invisible on a standard lipid panel. The American College of Cardiology recommends testing Lp(a) at least once in adulthood for cardiovascular risk stratification. If yours is elevated, you and your cardiologist can apply more aggressive management of other modifiable risk factors. There is currently one FDA-approved Lp(a)-lowering therapy in development (Pelacarsen), making baseline data even more useful.

Why is fasting insulin not part of standard blood work?

Fasting insulin is not included in a CMP or any standard preventive panel despite being one of the earliest signals of insulin resistance. The clinical system is largely organized around treating diabetes once diagnosed, not catching the 10 to 15 years of insulin resistance that precede a diagnosis. Fasting insulin requires a separate order, and most primary care physicians do not add it unless the patient has known prediabetes or diabetes. A fasting insulin above 10 uIU/mL in a fasting adult is worth a conversation with a clinician even when fasting glucose is normal.

Do comprehensive panels catch thyroid problems standard labs miss?

Regularly, yes. Subclinical hypothyroidism with normal TSH but low free T3 or elevated reverse T3 is a recognized clinical entity that a single TSH will not find. Hashimoto’s thyroiditis, the most common autoimmune condition in the US, is diagnosed by elevated TPO antibodies, which are not on any standard draw. Catching Hashimoto’s early allows for monitoring and intervention before significant thyroid tissue is destroyed.

Can I use my HSA or FSA to pay for Function Health or Superpower?

Yes. Both Function Health and Superpower memberships qualify as HSA and FSA-eligible medical expenses because they are diagnostic medical tests. Paying with a pre-tax health account effectively reduces the cost by your marginal tax rate, typically 22 to 37 percent for most US households. Confirm with your plan administrator if you have a limited-purpose FSA, as those have narrower eligibility rules.

How often should I run a comprehensive panel?

Twice a year is the standard cadence for most comprehensive lab memberships, and it is a defensible interval for most healthy adults. It gives you a before-and-after window for any lifestyle change and catches seasonal variation in vitamin D and other nutrients. If you are actively managing a condition or optimizing around a specific intervention (new training load, hormone therapy, dietary change), quarterly draws make sense. Talk to a clinician about what cadence fits your specific situation.