I spent years (and hundreds of dollars) on different blood tests, trying to find a durable solution to my problems. Why was I so tired all the time? Did I need to drink caffeine at a different hour? Was my sleep routine wrong? Was this just a normal part of aging?
I started with blood panels, but after that I was left on my own, still without solutions. So, I upgraded to panels with regular monitoring. In the end, it turned out that I needed some doctor involvement and ongoing treatment support.
You might be hoping to receive a lot of data like I did, but you might also want some insights that you can apply to proactively improving your health and wellness. Or, you might need meds and need them now to help with hormone or thyroid issues.
To help you find the provider that best fits your needs, we’ll compare four leading hormone optimization and longevity blood test providers:
- Lifeforce
- Function Health
- InsideTracker
- Marek Health
Topic Contents
TL;DR
- If you want data (a lot of data), Function Health can help.
- InsideTracker is there to give exercise and nutrition advice based on data. No meds though.
- Marek Health is robust, an a la carte option for those who want greater control over which biomarkers are tested, and the frequency of their panels.
- Lifeforce offers a closed loop solution, from start to finish with regular blood draws, important biomarkers, and robust treatment options.
Monitoring
Ongoing monitoring is one of the biggest differences between longevity testing providers. Some offer a once-a-year snapshot while others are designed for continuous tracking and adjustment.
Lifeforce
Lifeforce provides quarterly monitoring with quarterly blood work the data from which is regularly updated in the client portal for comparison.
Function Health
Function Health offers annual snapshots, with a single longevity blood test each year to give you just a quick look at how well you’re doing year over year.
InsideTracker
InsideTracker is pretty flexible. They let you choose the frequency of your testing so you can get anywhere between one quick test for that snapshot up to four tests per year, basically a good option for monitoring for people who want something between Function Health and LifeForce.
Marek Health
Marek health has regular follow-ups based on the treatment you are provided. They don’t have a set number of blood draws, but rather base this on individual cases.
Doctor Involvement
You may or may not want doctor involvement with your longevity blood tests. This involvement will look different based on the provider.
Lifeforce
Lifeforce has some of the highest doctor involvement out of the comparable longevity blood test providers. You receive dedicated one-on-one consultations from a clinician for 45 minutes every time you have that blood draw with consultations on an ongoing basis from health coaches who work with that data and your personal findings to encourage things like lifestyle changes in general wellness support.
Function Health
Function Health has comparably low doctor involvement. Instead, they generate a PDF report for your viewing pleasure, one which has been purportedly reviewed by a doctor but what that actually means is unclear.
InsideTracker
InsideTracker has very minimal doctor involvement as well. The results you get are actually AI driven so instead of being reviewed by a doctor it comes from the aggregate data that the algorithm can find associated with published medical research.
Marek Health
Marek Health has very high doctor involvement. The organization prides itself on intense Concierge support which comes from different medical providers and is offered to all clients based on individual results.
Number of Biomarkers
Each organization has a different level of biomarker depth and this relates as well to what it is they test.
Biomarkers are used by your doctor to diagnose diseases, with things like CT scans, blood pressure readings, or temperature readings but with longevity blood tests, those biomarkers are more predictive and designed to monitor how well you have responded to things like medications, exercise routines, supplements, or other lifestyle changes. These include measurements for things like LDL cholesterol which relates to heart risk, blood glucose levels, hormone levels, and other physiological markers.
Lifeforce
Lifeforce tests over 50 key biomarkers and is designed not just for data, but for action. Other competitors give you a sort of snapshot, a one-off look at how you are doing but this company provides a closed loop system where they capture critical biomarkers relating to things like organ function, metabolic health, and hormones, and then they connect those results to the clinicians who can prescribe things like supplements, peptides, or hormones.
Function Health
Function Health has the widest diagnostic breadth with over 100 biomarkers. This really makes them the best longevity blood test provider in 2026 for discovery. They give you the most data for the lowest cost but that data doesn’t come with the tools you need to make any changes or improvements.
It’s entirely up to you to take the results they generate for you based on that blood test, however, and go to a doctor and that doctor might be your primary care physician who may not necessarily be versed in longevity or preemptive health solutions.
InsideTracker
InsideTracker looks at 40 key biomarkers that are optimized for nutrition and performance. The hormone biomarkers you get here are excellent for lifestyle improvements. The company excels at integrating things like wearable data and your DNA to better improve your exercise and your diet.
However, they don’t have the clinical infrastructure to give you things like medical grade HRT so your focus is more on basic health, rather than hormonal health.
Marek Health
Marek Health is highly customizable, so you can choose the panel you want for the price you can afford.
Biomarker Relevance
All four of these providers differ in terms of how many hormones and biomarkers they look at, but it’s also important to review the clinical relevance of that biomarker data.
The table below offers a quick hormone biomarker comparison:
| Category | Lifeforce | Function Health | InsideTracker | MarekHealth |
| Total T | Yes | Yes | Yes | Yes |
| Free T | Yes | Yes | Yes | Yes |
| DHEA-S | Yes | Yes | Yes | Yes |
| Estradiol (E2) | Yes | Yes | No | Yes |
| Progesterone | Yes | Yes | No | Yes |
| IGF-1 | Yes | Yes | No | Yes |
| SHBG | Yes | Yes | Yes | Yes |
| Thyroid | Comprehensive | Comprehensive | TSH only | Customizable |
| LH and FSH | Yes | Yes | No | Yes |
| Cortisol | Yes | Yes | Yes | Yes |
So, how does this factor into choosing the best longevity blood test provider in 2026?
Lifeforce
Lifeforce’s focus is on biomarkers that have a direct correlation to prescriptions, things like performance medicine that can help with progesterone, thyroid issues, or testosterone issues. The panels provided here are designed to determine whether or not you might benefit from specific medical treatments.
Function Health
Function Health includes just about every hormone marker that you get but they’re non-prescriptive so you might get information about your LH levels but there’s no treatment plan that comes with it.
InsideTracker
InsideTracker focuses more on lifestyle and nutrition markers so they don’t have any sex hormones because the recommendations provided (by AI) center on supplements and food changes you can make rather than clinical or medical changes you can make. So, if you suspect you have a hormone deficiency, there’s really no diagnostic depth here to help you manage that.
Marek Health
Marek Health is pretty granular, so you get to choose the specific biomarkers you want to add if they aren’t part of the standard panel. I will say that this can be very overwhelming because you have to know which hormones or biomarkers might overlap to produce the symptoms you are experiencing and then it’s on you to choose the labs you want whereas companies like Lifeforce just streamline that process for all clients.
Treatment Follow-Through
What comes after your blood tests differs by provider too, and in some cases people want the best longevity blood test provider simply for the test itself while others want treatment follow through.
The table below offers a quick comparison for treatment follow-through options from each:
| Feature | Lifeforce | Function Health | InsideTracker | MarekHealth |
| Primary output | Medical treatment plan | Comprehensive data lab | Lifestyle action plan | Custom health plans |
| Prescription access | HRT, peptides, and clinical medications included | None | None | Wide range of bespoke prescriptions |
| Clinical access | 1:1 telehealth consults with clinicians | Limited, only written notes | None | Direct access to a medical team |
| Coaching support | Monthly health coaching | None | None | Varies by service level |
| Monitoring loop | Quarterly | Fixed schedule | User-driven, based on what you want | Varies by treatment needs |
Lifeforce
Lifeforce is very robust. They give direct access to not only the health coach consultations and the ongoing data from the quarterly blood draws, but direct access to things like peptides, HRT, and clinical grade supplements.
Lifeforce functions as an integrated medical partner and this means that the clinical membership gives you everything you need from start to finish with the blood draw, the one-on-one Telehealth consultation with the clinician, and prescriptions were necessary. You also get to meet with a health coach every month to make sure that the recommended lifestyle changes or medications really help you improve areas where you had suboptimal results from your blood draws.
Function Health
Function Health is self-directed, so you’re not going to find any direct treatment here. You’re going to get the widest diagnostic markers from your blood draw, but after that you have to find your own prescriptions or other treatments.
If you love data, this is what you’re going to get. They have an incredible volume of data that comes at the lowest fee out of all these options but that’s basically where it ends. You get the notes from your PDF but nothing connects you to a doctor, you can’t get a prescription, nor can you get lifestyle advice or supplements.
InsideTracker
Inside Tracker focuses on food, lifestyle changes, and supplements so the treatment follow through is not nearly as robust, it’s more just holistic.
Instead of one-on-one support from doctors and from health coaches, InsideTracker uses AI to generate lifestyle advice that includes things like what foods to eat, what supplements you might consider, and what workouts you should use to help you improve your overall well-being. But they don’t have anything relating to clinical interventions, so you won’t receive support if you need HRT or other hormone help.
Marek Health
With Marek Health, you’re going to get an extensive focus on performance medications and HRT in particular. The company has the most aggressive and customizable follow-through, which is why they have earned the nickname of offering the concierge service. This makes it ideal for high performance athletes. Just like Lifeforce, Marek Health gives direct access to a medical team as well as options for supplements and medications that are highly personalized for each client.
Summing Up
Overall, there are some great longevity blood test providers available in 2026, but the best one is really going to come down to your personal needs. Marek Health and Lifeforce provide a closed loop function where you get a blood test and then that leads directly to your ability to not only make lifestyle changes but access prescriptions. Function Health and InsideTracker meanwhile are strictly diagnostic tools designed to give you advice.
If you are worried about hormone issues or you want a lot of follow-through and doctor involvement, the closed loop options are probably going to be better for you. But, if you just want some quick data and you want the freedom to use that data how and when you see fit, the diagnostic options might be a better fit.
