How Does Rythm Use So Little Blood

2 min read

8/13/26

Key Takeaways

Modern clinical analyzers typically need only about 50–200 microliters per test yet traditional draws collect 20–30 milliliters and discard most of it.
Tasso+ collects roughly up to 1mL, and Rythm validates every assay for exactly that volume.
Because Rythm owns its lab, small-volume testing is a design choice, not a compromise.

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How Does Rythm Use So Little Blood

2 min read

8/13/26

Key Takeaways

Modern clinical analyzers typically need only about 50–200 microliters per test yet traditional draws collect 20–30 milliliters and discard most of it.
Tasso+ collects roughly up to 1mL, and Rythm validates every assay for exactly that volume.
Because Rythm owns its lab, small-volume testing is a design choice, not a compromise.

The Volume Myth

Large draws are a consequence of how traditional workflows evolved, not a requirement for accuracy. Standard vacuum tubes hold 5–7 milliliters because that suits venipuncture mechanics and handling. Labs over-collect for repeats and contingencies. Multiple tubes with different additives multiply the total a routine panel can pull 20–30 milliliters when each test actually needs a couple hundred microliters at most. The rest is discarded.

How Rythm Does It

Rythm validates its assays, instruments, and workflows specifically for the volume the Tasso+ collects. A single high-yield collection into a lithium heparin tube can provide enough plasma for more than a 30 measurements lipids, hormones, vitamin D, inflammation, and thyroid function among them. When a run needs repeating, there's typically sufficient volume remaining; in rare cases, we'll simply reach out for a fresh sample.

Does More Blood Mean More Accuracy?

No, not once the lab has enough validated volume for the instrument, quality checks, and any reruns. Accuracy depends on the analytical method and the integrity of the sample, not the size of the tube. Rythm just stopped taking blood it was never going to use.

FAQ

Does Rythm dilute samples?

No.

Is this a dried blood spot?

No, liquid whole capillary blood in a lithium heparin microtube, processed like any clinical specimen.

Frequently Asked Questions

How is Rythm different?

Most blood testing companies charge $500 or more for a single test per biomarker, providing only a one-time snapshot that doesn’t capture your long-term health trends or reflect your true baseline. This approach can lead to missed patterns or even misdiagnoses due to limited data. Rythm takes a different approach, using monthly tracking to build a detailed picture of your health over time. This allows for more accurate insights, better optimization, and a clearer understanding of how your body is evolving.

Does Rythm help me improve?

Rythm provides actionable suggestions and tips to help you optimize each biomarker

Is Rythm HIPAA compliant?

Yes, Rythm is HIPAA compliant. Your data is securely stored and handled in accordance with strict privacy and security standards.

Can I cancel anytime without fees?

Yes, you can cancel anytime without any fees.

Does Rythm accept HSA/FSA payments?

Yes, Rythm is HSA/FSA eligible. You can use your HSA or FSA card at checkout or submit your Rythm receipt to your provider for reimbursement.

How long does it take to get my results?

You will receive your results within 3 business days – as long as it's returned within 7 days of receiving your kit. Delays can occur if you do not send your sample back in time.