Bryan Johnson is a Silicon Valley tech entrepreneur who sold his company Braintree to PayPal for $800 million before embarking on the most daring journey of all: immortality. His “Don’t Die” movement—explored through a recent Netflix documentary—aims to achieve immortality, in whatever form that means: a digital cyborg, a cloud consciousness “upload,” or perhaps an elf-like body able to defy the effects of sin. In short, Bryan Johnson is wrong about nearly everything that matters: what a body is for, what death is, and where our final hope lies.
But he and his co-founder and girlfriend Kate Tolo are documenting their own bodies at a level of biomedical detail almost no one has attempted, and what comes out of it may end up mattering most for women, whose health conditions have gone underfunded and understudied for decades. In short, the Don’t Die project is anti-human. Its downstream effects may be a gift, especially to women.
(n-1): The Kate Tolo Protocol
At 6:30 in the morning, Kate Tolo has three minutes to spit into a tube and swab the inside of her cheek. Before seven, she removes what Bryan has been calling a “techno tampon,” takes her temperature, gives urine samples for cortisol and hormones, and measures her pelvic floor strength. Then comes sun therapy, blood pressure, a vaginal microbiome swab, and thirteen ounces of water, all before eight. The day continues like this until 9:55 at night, when she goes to bed wearing a sleep ring.
There are more than a hundred tasks on the schedule using more than fifty devices with a twelve-person medical team. The whole thing costs $2.6 million a year, funded by the company she co-founded, and she will follow this protocol for 100 days—or three months essentially—to understand her baseline health and biomarkers. For men, it only takes about 3 weeks; for women, it takes 3 months since our cycles are so complex, variable, and data heavy.
On the whole, they’re measuring 1,900 biomarkers across blood, urine, stool, vaginal microbiome, and more. Johnson says this will amount to fourteen million data points on a single menstrual cycle where they are gathering data at all four points in her cycle (menstruation, follicular, ovulation, and luteal), a full-body MRI, blood draws, retinal imaging, hormone tracking, skin analysis, a brain age assessment, grip strength, red light therapy, and the list goes on and on…
She is doing this, in her own words, to become the most measured woman in history.
The “Downstream Effect” May be the Best Thing for Women’s Health
Bryan Johnson’s health and longevity project has garnered an infamous reputation from the beginning—and has been well-marketed to stay in the news—but when he announced that he would be investing the same level of research into Kate, and specifically into assessing, diagnosing, and treating her reproductive health conditions, I think the heart of every woman in America grew more favorable toward Bryan and Kate about 10x that day.
An Endometriosis Diagnosis in 42 Days
Why? Because Kate had been in severe pain during her periods for about seven years.
They began to suspect endometriosis, which is a condition in which tissue resembling the lining of the uterus grows outside of it, causing severe pain and damaging a woman’s fertility and overall health. Researchers still do not know why it occurs, and as of 2022, for each woman who suffers from the condition the NIH devoted roughly only about $2 annually to researching it.
This is even worse when one realizes that it takes a woman, on average, up to ten years or more to receive a diagnosis, that one in ten women of reproductive age in the United States are estimated to have this condition, and that it is present in up to 50% of all cases of otherwise unexplained infertility diagnoses, making it a driving cause of infertility. So, you can imagine my excitement and that of many other women that someone would finally be devoting millions of dollars and innovative research to uncovering the underlying causes, improved treatment options, and better diagnostic tools to address it.
Kate initially underwent an MRI and a transvaginal ultrasound. Both are standard for endometriosis diagnosis, and both came back negative. Kate’s imaging, like many women's, came back “clear,” despite having the disease, which is why most women require a minimally invasive surgery to confirm it.
After this, they ran four specific tests that could (should?) become part of the standard women’s health protocol, especially when women experience such painful cycle-related symptoms.
These four tests were an endometriosis-specific ultrasound, an endometriosis blood test, an AI-read MRI, and a saliva test. (No surgery.) Notably, an “endo-specific ultrasound” is not a standard pelvic ultrasound. It’s a targeted protocol requiring an experienced sonographer who is trained to look for the disease, so general ultrasound care likely won’t cut it. These tests simultaneously confirmed that Kate does, indeed, have endometriosis. The wild part? It took about 42 days to diagnose it without surgery, against the 7-10 year timeline most women experience. In each case, the technology itself wasn’t new per se, but they were applying it with more detail and expertise than women are typically offered.
These tests also revealed adenomyosis and polyendocrine metabolic ovarian syndrome (PMOS, formerly PCOS), which is common for women who are struggling with complicated and painful cycles. In fact, 30-40% of women have at least one of these conditions, and they directly impact her quality of life and potential fertility.
The Saliva Test
If you follow the women’s health world, you may have seen a lot of recent buzz about a saliva test that can catch endometriosis. While Kate didn’t specify what saliva test she used or if it was central to her diagnosis, here’s what we do know:
A saliva test can identify endometriosis with 96.6% accuracy. It was validated in NEJM Evidence across 971 women. France reimburses it in a hundred hospitals. A woman in Dublin can order it, and yet an American woman with a decade of pelvic pain and a clean MRI cannot, at any price, with no FDA timeline in sight.
Essentially, a single cheek swab could help a woman determine the cause of her infertility or reproductive pain, even if her initial imaging comes back “clear.”
The validation study, published in NEJM Evidence, enrolled 971 symptomatic women aged 18 to 43 across 17 French hospitals, with diagnostic interpretations performed blind. It returned 96.6% overall accuracy, 97.3% sensitivity, and 94.1% specificity. Performance held across subgroups regardless of hormonal treatment, painkiller use, or site. (Yes, endometriosis tissue has been found in a woman’s… eye.) The test performed particularly well in exactly the population that has been failed hardest: women with symptoms suggestive of endometriosis whose imaging comes back negative or equivocal. Women, in other words, like Kate seven months ago and like many of you reading this.
Cycle-Timed Insights: Cholesterol Study
If you’ve been following Rethinking Fertility for any amount of time, you’ve likely heard me talk about the importance of assessing a woman’s health, data, and conditions throughout each phase of her cycle. Something that almost no researchers or doctors do when testing or treating women.
It turns out that the failure to do this leaves many women with an incomplete picture about their overall health.
Case in point: Kate recently shared findings from the NIH’s BioCycle Study. Researchers followed 259 healthy premenopausal women aged 18 to 44, with 94 percent giving 14 or more measurements across two cycles, charting phases with at-home fertility monitors. On average, total cholesterol varied 19 percent over the course of a single cycle.
HDL, the protective one, rose along with estrogen and peaked at ovulation. Total cholesterol, LDL, and triglycerides declined as estrogen rose, reaching their lowest point just before menstruation began. Between the midfollicular and midluteal phases, LDL fell by 4.9 percent and total cholesterol by 3 percent on average.
Here’s what that means in practice. Only 5 percent of these women consistently had total cholesterol above 200 mg/dL, the borderline high-risk threshold for heart disease. But nearly 20 percent crossed that line at least once.
In other words, one in five healthy women could be told she is borderline high-risk for heart disease based on nothing but which day she happened to book her blood draw. And the reverse is just as possible: a woman whose cholesterol genuinely runs high could be tested at her cycle’s low point, told her numbers look fine, and sent home.
A 2011 clinical review concluded that cycle phase should be taken into account when evaluating cholesterol in reproductive-aged women. As far as I can tell, essentially no one does this—and when a woman is on hormonal birth control, which flattens the variation altogether, we lose the signal entirely.
The Research Gap
As I noted in “What No One Taught You About Your Cycle” episode of Rethinking Fertility (and wrote about here), there was a good reason for this gap in women’s health assessments, and it wasn’t just misogyny or laziness on the part of doctors.
In 1977, the FDA issued guidance excluding women of childbearing potential from Phase I and early Phase II clinical research except in life-threatening conditions. This came in the wake of the thalidomide catastrophe, a drug that caused severe birth defects and deaths among the children of women who took it for morning sickness. It was a wake-up call to protect a woman’s fertility and her unborn child, and ensure women of reproductive age aren’t exposed to unnecessary risks. Well, the downside of this is that for 16 years essentially all women were excluded from research trials for drugs and treatments, which is also a huge problem given that men and women respond very differently to treatments, show different symptoms, and have different baseline levels of health and tolerance.
By 1993, Congress enacted the NIH Revitalization Act, which required the NIH and later the FDA to include women in early trial phases. Sadly, at this point, researchers still relied on the false assumption that the male body could be treated as a universal norm and that a woman’s fluctuating cycle was mere “noise” or distraction in study findings, rather than a key insight into a woman’s health. Thus, many studies today continue to require women to be on hormonal birth control—stifling and flattening her natural hormonal variation—or fail to analyze or report results by sex altogether.
But think about it: the individual who is currently spending the most money and social capital to reverse this and make real gains in women’s health (albeit with a study sample of n=1 to begin with) is Bryan Johnson.
As others have pointed out, many of the great advances in women’s health have come from men, often spouses, deeply grieved by the pain or suffering of a woman in their life. Driven by a desire to see her flourish, they went above and beyond even what “the science” was doing to seek answers. We can thank a husband for the development of the tampon. We can thank Dr. Thomas Hilgers for pioneering Natural Procreative Technology to give women and men real solutions to their infertility so that IVF wasn’t the default option. Or take George Papanicolaou, who developed the “pap smear” and countless data points that later enabled him to identify the early stages of cervical cancer in a woman.
The history of women’s health research is mixed at best, but it does us no good to blame an entire category (men). Instead, we should rely on wisdom and discernment to assess the merits of new health breakthroughs: receive what is good with thanksgiving, and discard the rest. It is for this reason that while I wholeheartedly reject the transhumanism, embryo-destructive polygenic selection tools, and general hubris of a man who believes that we are building God in the form of AI, I am grateful that the downstream impact—Bryan Johnson lite, if you will—of his work will likely result in incredible advancements in women’s health, including in the realm of infertility and reproductive health conditions.
The RRM Connection
This brings me to restorative reproductive medicine, or RRM. I can’t help but notice, and perhaps you have too, that many of the diagnostic tests and treatment protocols that Kate is exploring right now are very similar to what restorative reproductive medicine doctors have been doing for decades. (Sure, her approach is on steroids, but the concepts are very similar.)
Restorative reproductive medicine is an umbrella term covering three distinct approaches to treating infertility: NaProTechnology, NeoFertility, and Fertility Education and Medical Management (FEMM). Some physicians and clinics use the general term, others identify with their particular specialty. What most people do not realize is that this field has existed since the 1980s and has developed continuously since, with a whole ecosystem of adjacent clinics offering care aimed at restoring the health of the body so that natural conception can occur.
RRM begins from the conviction that infertility is not a standalone disease but a symptom of underlying conditions that make natural conception difficult or impossible. Infertility is not a material condition like a tumor or a ruptured appendix. The diagnosis is a signal that something is wrong in the man’s body, the woman’s body, or both. Causes fall roughly equally between the sexes, and studies have found that there are typically four or more underlying conditions at play in a given case. For women, the leading candidates include endometriosis, polyendocrine metabolic ovarian syndrome, uterine fibroids, blocked fallopian tubes, and hormonal imbalances. For men, low sperm count, poor motility or quality, erectile dysfunction, and a range of lifestyle factors.
Working from that premise, RRM physicians act as sleuths. Since reproductive health reflects overall health, the treatments aim to restore the body generally while removing the specific barriers to conception. In practice this means detailed cycle charting, hormonal blood draws timed to biologically meaningful days after ovulation rather than arbitrary calendar days, ultrasound series, semen analysis with DNA fragmentation testing, targeted endocrine and immune and clotting workups, lifestyle intervention, hormonal therapy, and corrective surgery where indicated. Like Kate, RRM doctors aim to capture as many data points as possible to diagnose reproductive health problems.
And, as with Kate, it is not only for people pursuing pregnancy. It addresses the root causes of painful or irregular cycles, low testosterone, and a range of conditions that follow men and women across their whole lives.
Rather than suppress, circumvent, or destroy the body, RRM seeks answers. It is quite similar—in spirit and in practice—to the approach of Bryan and Kate.
I’ve made this point before, but it’s worth making again. While there are many different philosophical and religious beliefs undergirding each, Silicon Valley and Social Conservatives share one major point of agreement: IVF, and our general approach to women’s health, isn’t cutting it.
A Catholic physician in Nebraska and a transhumanist in Los Angeles have arrived at substantially the same method, from metaphysical premises that could not possibly be further apart.
Dr. Thomas Hilgers, founder of Natural Procreative Technology, has worked against a hostile medical establishment for over forty years. Bryan and Kate endure the ridicule of many but know how to leverage social media for 21 million views on a single post. Both are seeking a similar aim of improving women and men’s health with real root cause care.
Hack or Heal?
The dividing line in policy, science, medicine and technology is whether one believes we should use these tools to restore or circumvent the human body. Another way of putting it is, do we want to “hack or heal” the human body? I co-wrote about this for The New Atlantis, where I described it as a choice between treating the body as hardware to be improved upon and treating it as a creature to be restored. At the end of the day, Bryan Johnson certainly sits on the “hack” side when it comes to certain issues, but the approach he and Kate have taken to her health thus far seems squarely in the realm of “heal.” Let’s pray it continues to be the case, at least as great insights and positive, new protocols are being developed.
Hope For vs. Hope In
Which brings me to the final distinction I want to leave you with, because it is crucial for understanding the current moment we’re in.
There is a big difference between hoping for something and hoping in it.
It seems that at the end of the day, as Bryan Johnson expressed in Ross Douthat’s final Interesting Times podcast and in a 2025 interview with Bari Weiss, he is placing his hope in these health interventions to make longevity gains that can one day beat death. As Christians, we can (and should!) hope for advancements to heal heartbreaking conditions and restore fertility, but that is not where we place our hope, joy, or ultimate sense of meaning. Indeed, Bryan Johnson may be on a mission to “Don’t Die,” but in Christ Jesus we have abundant life and the promise of resurrected and glorious bodies that will live forever.