Quick answer: Function Health results appear in your member portal within 5 to 7 days of your blood draw and cover up to 100+ biomarkers organized by body system. Each marker shows your measured value alongside two reference lines: the conventional “normal” range used by clinical labs and a tighter “optimal” range based on longevity research. A green result means you are in the optimal zone; yellow means borderline or outside conventional normal but not critical; red means clinically out of range. The portal also generates a written summary for each category and flags which physicians reviewed your panel. Talk to a clinician before changing any medication or supplement based on what you see.
What the Function Health Results Portal Actually Shows You
The results portal is the core product that separates Function from a standard Quest or Labcorp draw. When you log in, you land on a dashboard view that maps your biomarkers across eight to twelve body system categories: metabolic health, hormones, thyroid, cardiovascular, nutrients and minerals, complete blood count, kidney and liver function, and immune markers, among others depending on the panel version you ordered.
Each category card shows a pass/caution/flag summary at a glance. Clicking into any category opens the full marker list with a horizontal bar chart for each result. The bar spans the reference range, your value is plotted as a dot, and the optimal zone is shaded separately. This visual format is useful because it shows not just whether you passed but how far inside or outside a range you sit.
The portal also stores your historical results if you are a returning member, overlaying prior draws so you can see trends. A thyroid-stimulating hormone (TSH) value of 2.8 mIU/L might be in-range today, but if it was 1.4 six months ago, the upward trend is visible at a glance. That longitudinal view is where routine membership labs outperform a one-off urgent care panel every time.
For a detailed look at the interface design and navigation, see our function health app review.
Optimal Range vs Normal Range: The Most Misunderstood Part of Function Health Test Results
The single thing that confuses members most is the two-tier reference system. Conventional labs like Quest and Labcorp use population-derived reference ranges, meaning the band within which roughly 95 percent of people in a large (often sick) cohort fall. These ranges are designed to flag acute pathology, not to optimize health. A fasting glucose of 99 mg/dL is technically “normal” by clinical standards. Function flags it as borderline because consistent values above 90 mg/dL track with early insulin resistance in the research literature.
Function’s optimal ranges draw from peer-reviewed longevity and preventive medicine data, including work from institutions like the Cleveland Clinic and UCSF-trained researchers who helped build the platform. The result is that you will almost certainly see more yellow flags on a Function panel than on the same exact blood values run through a standard lab report. This is intentional and, for a well person trying to optimize, genuinely informative. But it also means you should not panic if half your markers show yellow: yellow is not red, and many optimal-range misses are addressed by basic lifestyle changes.
| Color | What it means | Typical action |
|---|---|---|
| Green | Within Function’s optimal range | Maintain current habits; recheck annually |
| Yellow | Outside optimal but within conventional normal, or borderline either way | Review lifestyle factors; consider follow-up with a clinician |
| Red | Outside conventional clinical reference range | Discuss with a physician promptly; Function flags these for review |
How to Read Function Health Results Category by Category
Knowing what each category section covers saves you from treating every flagged marker as equal urgency. Here is what the major sections include and what to look for first.
Metabolic Health
This section is where most American adults find their most actionable data. Key markers include fasting glucose, fasting insulin, hemoglobin A1c, and triglycerides. If glucose is in range but fasting insulin is elevated (anything above 8 to 10 uIU/mL is worth noting by optimal standards), you may have early insulin resistance that no annual physical would have caught. The HOMA-IR calculation, which Function derives from glucose and insulin together, is a sharper early signal than either value alone.
Cardiovascular Panel
Standard cholesterol reports give you total cholesterol, LDL, HDL, and triglycerides. Function goes further with apolipoprotein B (apoB), lipoprotein(a) (Lp(a)), and sometimes high-sensitivity C-reactive protein (hsCRP). ApoB counts the actual number of atherogenic particles in your blood, which predicts cardiovascular risk more accurately than LDL cholesterol alone in many patients. Lp(a) is genetically fixed and not modifiable by diet, which means a high result is useful information precisely because it tells you your baseline risk is elevated regardless of lifestyle and warrants more aggressive monitoring.
Thyroid Function
Function typically runs TSH, free T3, free T4, and thyroid antibodies (anti-TPO and anti-thyroglobulin). Most annual physicals run only TSH. Antibodies matter because Hashimoto’s thyroiditis can cause symptoms for years with a normal TSH while antibody levels are rising. A TSH of 2.5 mIU/L with anti-TPO antibodies above 35 IU/mL tells a different story than a TSH of 2.5 alone.
Nutrients and Vitamins
This section commonly flags vitamin D, magnesium, ferritin, B12, zinc, and omega-3 index. Vitamin D insufficiency (below 40 ng/mL by Function’s optimal threshold vs. the conventional cutoff of 20 ng/mL) is nearly universal in indoor-working Americans. Low ferritin, even within the broad clinical normal range (which bottoms out at 12 ng/mL for women), can explain fatigue at values below 30 to 40 ng/mL. These are the markers most primary care physicians never test on a well-visit because insurance rarely reimburses them without symptoms.
Hormones
For men, Function tests total testosterone, free testosterone, SHBG, estradiol, DHEA-S, PSA, and LH/FSH. For women, testing is cycle-dependent but typically includes estradiol, progesterone, testosterone, DHEA-S, and FSH. The free testosterone calculation matters more than total testosterone: a man with total testosterone of 550 ng/dL but high SHBG may have less active hormone than one with a total of 420 and low SHBG.
Red Flags Worth Immediate Action (Not Every Flagged Marker Is Equal)
Function’s portal flags dozens of markers, but some carry urgency and others are background noise for a healthy person. Prioritize follow-up when you see any of the following in red:
- Hemoglobin A1c above 6.4 percent (diagnostic threshold for diabetes)
- eGFR (estimated glomerular filtration rate) below 60 mL/min/1.73m2, which signals reduced kidney function
- ALT or AST liver enzymes above 2x the upper limit of normal
- TSH below 0.4 or above 4.5 mIU/mL
- Complete blood count showing hemoglobin below 12 g/dL (women) or 13.5 g/dL (men)
- Calcium above 10.5 mg/dL on a repeat draw (hypercalcemia warrants workup)
- PSA above 4 ng/mL in men under 60, or above 3 ng/mL in men under 50 by some guidelines
A yellow flag on vitamin D or magnesium? That can wait for your next grocery run. A red flag on eGFR or liver enzymes warrants a call to your primary care physician, not a supplement stack from a podcast ad.
What to Do With Your Function Health Biomarker Report: A Practical Sequence
Most members read their results, feel vaguely motivated for 48 hours, and then do nothing specific. That is the gap Function as a platform cannot fully close. Here is a more effective sequence:
- Screenshot the summary page first. The portal gives you an overall category score view. Screenshot it to track changes after your next draw.
- List your red and yellow markers in a single document. Group them by category. You will likely find patterns: metabolic markers cluster together, nutritional markers cluster together. That clustering points to root causes rather than a dozen unrelated problems.
- Prioritize by modifiability and urgency. Lp(a) is not modifiable. Fasting insulin is highly modifiable. Vitamin D is the easiest fix in the building. Address the easiest high-impact items first.
- Bring the report PDF to your doctor. Function generates a downloadable PDF of your full results. Your PCP may not have ordered these tests, but they can interpret them and order follow-up if needed. The function health customer service contact page has instructions for exporting and sharing your data.
- Retest the specific flagged markers in 90 to 120 days. You do not need another full Function panel. Quest or Labcorp can run a targeted follow-up (fasting glucose, insulin, and A1c, for example) for under $50 cash at most locations.
Function Health Optimal Ranges: Where They Come From and When to Trust Them
Function does not publish a single referenced source document for all its optimal thresholds, which is a fair criticism. The ranges appear to draw from a synthesis of functional medicine literature, including work published by groups like the Institute for Functional Medicine, landmark cardiovascular trials like JUPITER and the INTERHEART study, and peer-reviewed longevity research from labs studying centenarian populations.
Where the optimal ranges are most defensible: apoB, Lp(a), fasting insulin, hsCRP, and vitamin D all have robust evidence bases for tighter thresholds than conventional labs use. Where they are more debatable: some hormonal optimal ranges (especially DHEA-S and certain testosterone interpretations for older adults) reflect integrative medicine consensus rather than RCT data.
The practical rule: if a marker is flagged yellow by optimal standards but green by conventional standards and you have no symptoms, monitor it. If it is flagged red by conventional standards, act.
For a broader look at what the membership includes and whether the panel is worth the price, read our function health review.
The simplest way to actually get this done
Superpower is a full-body lab membership that runs 100+ biomarkers, has each result reviewed by a doctor, and tracks your numbers year over year (about $199/year). It is what we point readers to when they would rather get one clean, complete draw than chase single tests one at a time. Here is superpower reviewed in full.
Getting a Second Opinion on Your Function Health Results
Function includes physician review of flagged markers, but that review is asynchronous and generalized, not a consultation. For any red flag, or for a pattern of yellow flags that concerns you, a follow-up with a licensed clinician is the right move.
Options in order of accessibility:
- Your existing PCP. Most will engage with a comprehensive third-party lab report, especially a clean PDF. Bring specific questions, not just the full document.
- Telehealth platforms. Services like Hims, Ro, and Levels Health offer physician consults by video, often within 24 hours, and several are familiar with direct-to-consumer lab panels.
- Functional medicine physicians. If your results show a complex hormonal or metabolic picture, a board-certified functional medicine physician (look for IFMCP or ABIHM credentials) is trained to interpret these panels in the way Function intends them to be used. Expect to pay $200 to $500 out of pocket for an initial consult.
See our article on getting a second opinion on Function Health results for a step-by-step on preparing for that conversation.
Comparing Function Health Results to Your Annual Lab Work
Most annual physical blood draws run a basic metabolic panel (BMP) or comprehensive metabolic panel (CMP), a CBC with differential, a lipid panel, and maybe TSH. That is roughly 15 to 25 individual data points. Function’s standard draw covers 100 or more. The delta matters most in these categories where your annual labs are almost certainly leaving you blind:
| Marker | In standard annual labs? | In Function Health panel? | Why it matters |
|---|---|---|---|
| Fasting insulin | Almost never | Yes | Early insulin resistance invisible on glucose alone |
| ApoB | Rarely | Yes | Better cardiovascular risk predictor than LDL |
| Lp(a) | No | Yes | Genetic cardiovascular risk; need to know your number once |
| Free T3/T4 | Usually only TSH | Yes | TSH alone misses conversion problems |
| Thyroid antibodies | Only if TSH is abnormal | Yes | Hashimoto’s detectable before TSH changes |
| Vitamin D (25-OH) | Sometimes, not always | Yes | Deficiency near-universal; directly supplementable |
| Omega-3 index | No | Yes | DHA/EPA status; guides fish oil dosing |
| Ferritin | Only if anemia suspected | Yes | Low-end normal ferritin causes fatigue before anemia |
To see a full breakdown of the membership price relative to ordering these same tests separately, read our piece on function health cost.
FAQ
How long does it take to get Function Health results?
Most members receive their results within 5 to 7 business days of their blood draw. Complex panels or high lab volume periods can push this to 10 days. Function sends an email notification when results are ready. The portal does not release partial results by category as they come in; the full report posts at once.
Can I download my Function Health biomarker report as a PDF?
Yes. The portal offers a PDF export of your complete results, including reference ranges, your values, and the written category summaries. The PDF format is accepted by most physicians and telehealth platforms. The file includes the lab accreditation information and the physician names who reviewed your panel, which adds credibility when sharing with your own doctor.
What does it mean if a Function Health result is flagged but my doctor says it is normal?
Your doctor is likely using conventional clinical reference ranges, while Function used its tighter optimal thresholds. Both can be correct in different contexts. Conventional ranges are designed to detect disease; Function’s optimal ranges are designed to detect suboptimal function before disease develops. For most yellow-flagged markers, this discrepancy is expected. For red-flagged markers, you and your physician should be on the same page regardless of which system generated the flag.
How do Function Health optimal ranges differ from normal ranges?
Conventional normal ranges are statistically derived from population studies and are often wide enough to include people with subclinical dysfunction. Function’s optimal ranges are drawn from preventive medicine and longevity research and are intentionally tighter. For example, the conventional TSH normal range runs from roughly 0.4 to 4.5 mIU/mL; many functional medicine practitioners and the optimal range Function uses prefer values between 1.0 and 2.5 mIU/mL for optimal thyroid function. The difference is not arbitrary, but the evidence base for tighter thresholds varies by marker.
What should I do if I get a red result on my Function Health test results?
Contact a licensed clinician, ideally your primary care physician, and share the PDF of your results. A red result means the value is outside the conventional clinical reference range, which is a threshold designed to catch pathology, not just optimization gaps. Do not self-treat a red result with supplements or dose changes before speaking with a physician. Function’s platform also flags red results for physician review internally, but that is not a substitute for a one-on-one clinical conversation.
Does Function Health show results for every biomarker at once?
Yes, the full panel posts together once all results are validated and reviewed. Function does not release individual marker results as they process. If you are anxious about a specific result, the 5 to 7 day wait is the standard timeline and there is no expedited release option as of 2026.
How does the Function Health results portal compare to the app?
The portal and the app (iOS and Android) show the same underlying data. The app adds push notifications for new results and is optimized for mobile browsing of individual markers. The desktop portal is better for the full trend graph view and for exporting your PDF report. Members who want to dig into longitudinal data tend to prefer the desktop experience. Our function health app review covers the interface differences in detail.
Can Function Health results be used for insurance purposes?
Function results come from a CLIA-certified lab (Quest Diagnostics processes most draws), so they are clinically valid documents. Whether your insurer will accept them for underwriting or coverage purposes depends on the insurer. For life insurance underwriting, a Function panel PDF with lab accreditation details is generally treated the same as any third-party lab result. For health insurance claims, Function charges are not typically reimbursable, though some HSA/FSA accounts cover the membership fee. For details on reimbursement, see our piece on Function Health HSA FSA eligibility.
What is the difference between a Function Health result and a Superpower result?
Both platforms run 100+ biomarkers through CLIA-certified labs and provide results via a member portal with optimal-vs-clinical range comparisons. The core biomarker overlap is significant. Superpower differentiates with a doctor review model that includes a direct-to-member physician note on your specific results rather than a generalized category summary, and at about $199 per year its pricing is competitive. If you are comparing the two platforms before choosing, read our superpower blood test review for a side-by-side breakdown.
