Summary at a glance
Rythm Health advertises $79 a month, but buyer-reported totals land near $101 once the kit and shipping are added, roughly $1,210 a year.
Function Health costs $365 a year for 160+ lab tests, run twice a year, with a clinician reading every result.
Rythm lists 27 biomarkers, 24 measured plus 3 computed ratios, and gives you AI insights rather than a clinician review.
Users who ran Rythm beside a Quest draw report hormone numbers that do not match, so Rythm works best as a trend against its own earlier panels.
Function Health members complain most about what happens after results arrive: generic clinician notes, no Quest portal sync, PDF-only export and chat-only support. Function has since added inbound wearable sync via Connected Apps, but lab results still do not flow out.
This comparison reports published prices and what buyers wrote in public about two direct-to-consumer blood testing services. Neither was tested first-hand. Blood markers covering liver and kidney function, hormones, heart health and energy need a qualified clinician to interpret them against your own history. Nothing here is a diagnosis, a treatment plan or a reason to start, stop or change any medication. Take unexpected results to your doctor and confirm them with a standard lab draw before acting.
Rythm Health vs Function Health: Which One Should You Buy?
Pick Rythm Health if you want a small blood panel repeated every month with no needle. Pick Function Health if you want one wide baseline of 160+ lab tests with a clinician reading them. Rythm watches a few markers often. Function maps most of your body twice a year.
The money is closer than the headlines suggest.
Rythm advertises $79/mo + shipping and tax. Buyers report paying about $101 once the kit and shipping land, and one four-star Trustpilot reviewer puts it plainly: "it is $101.00 all in every month" trustpilot.com. Function Health charges $365/yr.
The two weak points sit in different places. Rythm's is trust in the numbers. One reader collected their Rythm sample the same day as a scheduled Quest draw and got results "consistently at least 20 points higher than Quest" reddit.com. Function's problem arrives after the results do: members say their data is stuck in the platform, with no Quest portal sync and PDF-only export. Function has since added inbound wearable sync via Connected Apps (steps, sleep, resting heart rate from Apple Health, Oura, Fitbit and Garmin), but lab results still do not flow out reddit.com.
Rythm's Trustpilot score is 4.7 out of 5 across 2,232 reviews. The company asked for 238 of the 258 reviews read for this article, through its own invitation links.
How Do Rythm Health and Function Health Compare?
The two products answer different questions.
Rythm answers what changed since last month. Function answers what is going on across your whole body right now,.
Panel size is the clearest split. Rythm lists 27 biomarkers, 24 measured plus 3 computed ratios, against Function's 160+ lab tests.
Cadence is the other split, and it changes what your year looks like. Rythm posts you a kit every 30 days, you collect at home, and you build twelve small data points over a year. Function books you into a Quest location twice a year, with on-demand testing in between. One gives you a short list you can watch move, the other a long list you see twice.
Function Health app features: private AI chat, protocols, 160+ lab tests and health recordsRythm Health
$79/mo + shipping and tax
Function Health
$365/yr
Rythm Health
27 listed biomarkers (24 measured + 3 computed ratios)
Function Health
160+ lab tests
Rythm Health
One panel every 30 days
Function Health
2x/year + on-demand testing
Rythm Health
At-home Tasso+ capillary collection kit, free FedEx pick-up from your home
Function Health
Blood draw required, at 2000+ lab locations
Rythm Health
No clinician review of results; insights are AI-generated
Function Health
Clinician review of every result
Rythm Health
Available in all 50 US States; HSA/FSA eligible
Function Health
No insurance needed; HSA/FSA eligible
Is Rythm Health Worth $79 a Month?
Rythm fits one buyer well. You cannot face a needle, and you want to watch a few markers move month by month.
The painless collection is the one thing nobody argues with. Trustpilot reviewers who faint at ordinary draws describe finishing a test alone at home. One wrote: "It was actually painless!! Physically and emotionally." trustpilot.com
Accuracy is the harder question. A Reddit user collected their Rythm sample the same day as a scheduled Quest draw, found their markers "consistently at least 20 points higher than Quest", and was refunded. Their doctor, who set the tighter condition that the two draws fell within an hour of each other, said Rythm is "fine for tracking trends against other Rythm results" and not a replacement for the Quest draws reddit.com.
Clinical laboratory staff go further. In a September 2025 thread on r/medlabprofessionals, the top comment is "Feels like Theranos" with 1,145 upvotes reddit.com. Other lab professionals in the same thread push back, noting the collector is FDA-cleared and that not every marker needs spinning within two hours of collection.
The small panel trips people up too. One reviewer signed up to watch hemoglobin and haematocrit, then got two panels in a row with both fields left blank trustpilot.com. There is no A1c, no fasting insulin and no CBC with differential. Rythm added GGT and ALP to the liver group, so the liver enzymes are covered.
Total testosterone runs into an assay ceiling: one forum member reports that levels above 1500 come back only as a number between 1400 and 1500 anabolicsteroidforums.com.
Rythm collector held against the upper armRythm Health
Needle-free at-home capillary collection via the Tasso+ device, which gets blood-phobic people tested at all
One panel every 30 days, so month-to-month change is visible
Results within 3 business days
Skip up to 90 days at a time or cancel anytime with no fees
Free FedEx pick-up from your home
Only 27 listed biomarkers (24 measured + 3 computed ratios), far narrower than Function Health
Shipping and tax are added on top of $79/mo, and buyers report about $101 in total
Hormone results diverge from reference-lab draws for several users who ran both
No clinician review of results; insights are AI-generated
Some markers are sex-gated: Progesterone female only, Hematocrit and Hemoglobin male only
Is Function Health Worth $365 a Year?
Function Health buys breadth. The $365/yr membership covers 160+ lab tests, twice a year plus on-demand testing, at 2000+ lab locations, with clinician review of every result.
Members rarely argue about the breadth. The arguments start once the results land.
The clinician write-up is the first one. "I put my results into ChatGPT and got more helpful feedback than Function’s clinician notes," one member wrote in March 2026 reddit.com.
Getting your own numbers out is the complaint with the most weight behind it. A top comment in an August 2025 thread reads: "And the data is stuck into their platform. They no longer allow Quest to keep the data and there is no Apple Health integration." reddit.com A PDF download does work, and members who tried it report sending results to their own doctor without trouble. What you lose is the Quest portal sync and any machine-readable file.
Support is the other one. "They lost my blood work. You can only chat with an extremely inefficient AI bot," a member wrote in October 2025 reddit.com. There is no phone line.
The Function Health app showing 147 biomarkers, in-range counts and a 37.2 biological age on a phoneFunction Health
160+ biomarkers, including tests members say their own doctor could not order
Clinician review of every result
2000+ lab locations
No insurance needed
HSA/FSA eligible
Still expensive at $365/yr
Blood draw required, so there is no at-home option
Clinician notes read as generic AI text to many members
Lab results stay inside the platform: no Quest portal sync, PDF-only export. Function now accepts inbound wearable data via Connected Apps, but results do not flow back out
Support is chat and email only, with no phone line
Which One Should You Pick?
Function Health is the better first purchase for most people. One $365/yr membership covers 160+ lab tests twice a year, and a clinician reads every result. That is what you want when you have no recent baseline. Rythm Health earns second place, as a cheap monthly check on a handful of markers between those draws.
Buy Rythm first only if the needle is the reason you have never tested. That barrier is real, and Rythm removes it.
Then read its numbers as their own line on a chart. The doctor quoted above and the product's longest-running public user land in the same place: trend Rythm against Rythm, and keep a venous draw for decisions that matter youtube.com. That user carries a Rythm referral code, so read the verdict with that in mind.
Price cuts the same way. At about $101 a month, twelve months of Rythm costs more than three years of Function Health, for a fraction of the markers.
If you buy both, collect one Rythm sample close to a scheduled lab draw. Comparing the same day tells you how far apart the two run for your own blood.
Choose Rythm Health instead if a needle is the reason you have never tested, or if you want a few markers checked every 30 days between venous draws.
Function HealthOne $365/yr membership covers 160+ lab tests twice a year with clinician review of every result, which is what a first baseline needs. Rythm Health lists 27 biomarkers and has no clinician review.
Blood work, scans, test results, medical reports — finally in one place and connected to how you actually feel. aelívra tracks biomarkers and health records over time, so you can see what's trending in the right direction and walk into your next appointment knowing exactly what to discuss.
How We Researched This Comparison
Neither product was tested first-hand for this comparison. Prices and panel details come from each company. Everything a buyer says here was published in public and quoted as written.
For Rythm Health, that is 258 Trustpilot reviews read in full, nine Reddit threads plus the whole r/rythmhealth community, both pages of a 53-post testing forum thread, two YouTube reviews and two written reviews, one of them self-funded. About 120 distinct opinions.
One caveat outranks the rest. The company asked for 238 of those 258 Trustpilot reviews through its own invitation links, and it pays users $20 for each referral. So the five-star mass measures Rythm's invitation pipeline rather than spontaneous satisfaction, and the unprompted signal sits in the critical minority.
Two of the Rythm threads are clinical laboratory professionals critiquing the collection method, not customers. Several others are testosterone-therapy users, whose priorities are not a general buyer's.
For Function Health, the record is 1,322 Trustpilot reviews with the most recent page read in full, ten App Store reviews, ten complete Reddit threads holding about 300 comments, and two published testers who paid their own way. Roughly 340 opinions.
Founders and staff from rival testing companies reply inside several of the Function Health threads read for this article, recruiting unhappy members. Switching stories there carry a commercial interest.
Frequently asked questions
Does Rythm Health really cost $79 a month?
The panel is $79/mo + shipping and tax. Buyers report paying about $101 once those are added, which comes to roughly $1,210 a year.
Can Rythm Health replace a lab blood draw?
Users who ran both, and one of their doctors, say no. Treat Rythm as a trend line against its own earlier panels, and keep a venous draw for decisions.
Can you export your Function Health results?
You can download a PDF and send it to your doctor. You cannot pull a spreadsheet or have Quest post results to your MyQuest portal. Function now accepts inbound wearable data from Apple Health, Oura, Fitbit and Garmin via Connected Apps, but lab results do not flow back out to those apps.
Which one is better for tracking hormones?
Neither is ideal. Rythm caps total testosterone and ran high on hormones for several users who checked against a lab. Function tests twice a year, so month-to-month change stays invisible.
Sources
Cameron founded aelívra after years of living an unknown no one could answer — navigating chronic health complexity through a medical system that wasn't built for it. That experience became a conviction: everyone deserves to feel truly alive, and no one should have to accept not knowing as a way of life. His work sits at the intersection of data science and functional health and wellbeing, turning the latest trusted medical research across news, health, wearables, biomarkers, and more into advice everyday people can use on their journeys toward feeling better. Every article is grounded in peer-reviewed evidence and linked to its primary source. This content is for informational purposes only and does not replace medical advice.
