Beyond Estrogen: Testosterone, longevity, and the science of what comes next — with NYT journalist Susan Dominus

Stacy London

Susan, I'm so happy you're back. We were just on the precipice of getting into testosterone in our first recording and ran out of time. We naturally produce testosterone, and if we lose it the same way we lose estrogen and progesterone, it makes sense that we'd want to replenish it. If I understand correctly, it's about a tenth of what men make. But the real issue isn't whether testosterone has use value for women — it's that we don't have a regulated delivery mechanism. When did you first start hearing about it?

Susan Dominus

I ran an article about it a few months ago in the New York Times Magazine. It did come up when I was first reporting on menopause, maybe two or three years ago. At that point, the menopause society wasn't really ready to encourage or support it. But in the UK, testosterone was very much a part of the menopause conversation — they were already advocating for it three years ago.

I got interested in it mostly because I started to see it bubbling up on social media. I had a suspicion about it — maybe it's that puritanical part of us that says do the bare minimum you need, nothing more. But when I started looking into it, people I really respect told me they thought it was maybe one more piece of the puzzle.

It's not exactly mainstream for OBGYNs to prescribe it. It's kind of gotten taken over by wellness centers, longevity centers, compound pharmacists. Some women are taking it in very high doses — and that's a totally separate and fascinating cultural phenomenon.

Stacy London

So the delivering mechanism is a real issue. We have pellets, compounding in gels or lotions. We don't have a truly regulated way to deliver testosterone to women. Pellets have had some concerning side effects, and I don't think they're FDA approved as a delivery mechanism. What have you found in terms of how to get women testosterone — and why should women consider it?

Susan Dominus

I wouldn't go on the record saying women should or shouldn't take it — I think it's a very personal choice. You're right that it's not FDA approved for women in the US. In other countries, like Australia, the counterpart to the FDA has approved it. And that's one of the reasons it's been extremely well studied there, by a researcher named Susan Davis.

What she found is that when women replenish their testosterone to levels around what they had in their late thirties — not peak, but respectable — there is one and only one benefit that the research bears out: in some women, there's a small increase in libido. That's what it's best for.

Stacy London

That's so interesting. I'd heard testosterone could also help with muscle and energy levels. I may have only heard anecdotal evidence, but I'm curious — testosterone is responsible for more than libido in the body. And I wonder why the US is so far behind when Australia has well-documented research on this.

Susan Dominus

I think it speaks to this American puritanical impulse. It makes us uncomfortable specifically because testosterone is a hormone we associate with masculinity. In a country that's probably more religious on average than Australia, there are cultural filters that make people more averse to anything that feels gender-bending.

In Australia, what they found at those standard doses is that it doesn't tend to have much of an impact on muscle, bone strength, or recovery from injury. You can find isolated studies suggesting otherwise, but the single most respected authority on the subject will tell you honestly: it's really just libido. That's the only difference from placebo at those levels. Which is no small thing.

You will hear women who say anecdotally — and I've interviewed many who take it at low doses — that they do feel more energy, more of a general pep in their step, as well as feeling more alive to sex. It's just not what the research bore out, for whatever reason.

High-Dose Testosterone: A Different Conversation

Susan Dominus

When you take it at high doses — doses that put testosterone levels higher than a woman even had in her youth — you can start to see significant effects. Pellets sometimes give you levels much higher than what you'd expect in a premenopausal woman. At those levels, women do feel more energetic. Some say they talk faster. I kept talking to women on high doses who told me, 'I never would have gone back and gotten my PhD if I weren't on testosterone. It made me feel invincible.'

There are side effects that come with it that some of us might not be willing to risk. And some women told me that at those high levels, they felt really angry, or even uncomfortably aroused — distracted by it in a way that didn't feel right to them.

Stacy London

I've also heard that your level of empathy and compassion can go down at high doses.

Susan Dominus

I've heard reports of that, yes. Nothing comes without a trade-off — and hormones show that so clearly. A lot of anger, road rage, women behaving in ways that surprised them. It's disconcerting because it makes you think: are we our hormones? Yes, a little bit, I think.

One couple I interviewed — their whole sex life had changed because the wife had gone on pretty high levels. And it wasn't just that their sex life got better. When you're having a lot of sex with your partner, sometimes it makes you feel closer and more alive. They said they started socializing more, had more fun together even outside of sex. I heard that from many couples.

That said, none of the NAMS-certified doctors I interviewed would ever prescribe hormones at a level higher than what's been studied long-term. Not just because of side effects like increased hair growth or voice deepening — but because a lot of testosterone converts to estrogen. So if you have an estrogen-sensitive breast cancer, what are high levels of testosterone going to do? We just don't know.

We don't have a large population-based study over 20 years for women on high-dose testosterone. Some women stay on those levels for five to seven years. You're rolling the dice a little bit. And some would say: that's fine. I'd rather have 10 more years of great sex. Not everyone would make that calculation.

The Risk Calculation

Stacy London

Right — it comes down to how risk-averse you are and what that risk-benefit analysis looks like for you. The conversation around testosterone has mostly been about sex, not energy or muscle. And we do have a lot of anecdotal evidence. I remember interviewing Dr. Kelly Casperson, who's a urologist and very pro-testosterone. She told me she started recommending it to women after seeing how easily we give hormones to men who need them — and that testosterone is the missing piece, something we don't talk about as a naturally produced female hormone. The number one thing her patients told her: 'I feel like myself again.' Which mirrors what I've heard across the board from women going through menopause.

Susan Dominus

Kelly and I spoke many times. She's wonderful. I will say she overstates the case a little — she knows she's on the pro side. But there is a spectrum. The dose that's been studied is one that brings you back to testosterone levels of your late thirties. Who's to say it would be terrible to go slightly higher? People like Kelly think: what if we brought it back to where you were at 25?

It's not just a binary of either the low standard dose or the high 'jumping your husband three times a day' dose. There are doctors who will go a bit more than what's been studied, in the name of a little more zest. Who am I to say that's terrible? A lot of doctors would push back on that — they'd say it's not studied, we don't know. But I do think women are entitled to make their own choices.

Stacy London

We're backed up by the fact that so much hasn't been studied. And here we are with a very high-need population who's saying: I can't wait 20 years for you to do the research. We need help now.

Susan Dominus

The sad thing is that a 20-year study is incredibly expensive. As far as I know, nothing like that is even underway.

I haven't started testosterone myself. My feelings about it are partly irrational. Even though the research at the standard dose doesn't show risk for hair loss, I'm afraid — what if I'm the one person? And yet on the other hand, the research shows there isn't going to be hair loss at that dose. So I know my fear isn't entirely rational.

Stacy London

Hair is a huge identifier — for men and women both. That feels like a very real part of the risk-benefit calculus.

Susan Dominus

It is. And there's actually something potentially coming down the pike: a treatment for hair growth with no currently known side effects. So sometimes I think, once that's on the market and has been around a while, maybe I'll be less afraid to try testosterone.

Delivery, Telehealth, and FDA Approval

Stacy London

My OB-GYN gave me testosterone gel — the kind prescribed for men — and said to use a tiny amount behind my knee every day. My problem was I didn't know how much 'a tiny amount' was. I was afraid I'd take too much or too little, so I wound up not taking it. Not exactly user-friendly.

Susan Dominus

That's exactly the problem with it not being FDA approved for women. Testosterone is approved for men, so if you want a regulated, carefully prescribed dose, you have to get it in portions made for men — essentially a packet or tube for a man — and make it last ten days. Not convenient. Not user-friendly.

There is talk of a testosterone pill for women being put before the FDA, which could get approval down the road. That would be a significant step.

I also want to flag something about telehealth. I think it's been largely good for women's access to menopause care. MIDI Health, for example, does prescribe testosterone and to my understanding requires a baseline blood test and monitors levels over time. But one general caution about telehealth: I always like to separate my doctor from my pharmacy. A lot of telehealth operations have both the prescribing doctor and the drug sales in one place — there's a potential for motivated reasoning there. That doesn't mean it's bad, but it's worth knowing as a patient.

Stacy London

That's an incredibly important distinction. The whole point of this conversation is to give people more agency, not less. Knowing whether your provider also profits from what they're prescribing is part of being an informed patient.

Also — I have a friend who has her estrogen, progesterone, DHEA, and testosterone all compounded into a single cream. I'd love that kind of convenience. My concern is that with compounding, you don't always know exactly what's in it and at what levels.

Susan Dominus

That's exactly right. And if you're going to try testosterone, taking a man's tube and making it last ten days is probably more precise than trying to measure out a dollop. It'll even out over the course of the tube. A pill would be better still — I think that would change a lot for women.

One thing worth noting: it does take a while to kick in. What I've heard from a lot of women is that the first three months they felt nothing. Then reliably, after three months at the standard dose, a little light goes on. It's not overwhelming — they just feel sexually a little like they used to. For a couple whose sex life has basically stopped, even that shift — moving from 'I must do this to save our marriage' to 'oh, that actually sounds like it could be fun' — is a significant quality-of-life change.

The Research Gap

Stacy London

I want to close the loop on something from Part 1. I think a lot of women assume that after the study that sent everyone into a panic and essentially killed off hormone therapy for 20 years, someone somewhere would have said: why don't we run a follow-up? You told me you weren't aware of any long-term randomized controlled trials on MHT currently running. Is there anything new there?

Susan Dominus

I'd love to be corrected, but I don't believe there is one. Not on the scale of that original study. That was one of the most expensive, well-funded studies in history — the NIH was incorporating computers into their systems for the first time just to coordinate the research centers involved. It practically changed healthcare.

Stacy London

Do you think it was almost too big a study to fail? So many departments coordinating, so much money invested — I wonder if that contributed to how it was received.

Susan Dominus

I don't think the size was the core problem. It was more how it was presented. The media presented it as: menopausal hormone therapy is very dangerous. But even at the original press conference, the doctor speaking said, 'For an individual woman, the risk is quite low. It's only that across a population, we will see an uptick in cases of breast cancer.'

There's also the context: they expected MHT to show massive cardiovascular benefits. They thought it was going to be so healthy for women that it should practically be in the water. When the results came back differently than expected, I think doctors felt guilt and just overcorrected. We're now in a period of over-correcting in the other direction — trying to restore what was lost.

Longevity, Cellular Rejuvenation, and the Future of Aging

Stacy London

I went for a physical recently and my biological age came back as 39. I'm about to be 57. I haven't been doing anything radical — strength training, organic food, more sleep, vitamins. Things that create a better chance for a longer life. But what does that mean? What have I actually done to be 20 years younger biologically?

Susan Dominus

Those aren't small things at all. I went to a lab called Altos Labs for a New York Times Magazine piece that just ran. It started with $3 billion in startup funding — probably the biggest biotech launch in history, funded by Bezos and Yuri Milner. They've recruited the most brilliant academics researching cellular rejuvenation.

At the end of my time there, the CEO — Hal Barron, who came from GlaxoSmithKline and is kind of a legend — said: 'We know we're going to be able to figure this out, because we know it can be done.' And I asked, 'Well, what is it?' And he said: exercise, sleep, social connection, and eating right. Those are not small things. Those are the things.

Stacy London

What exactly is cellular rejuvenation?

Susan Dominus

The technical term is partial epigenetic reprogramming. They've found a way to treat cells that takes them back to an earlier stage of development — not all the way to embryonic state, which would be terrible because they wouldn't be specialized anymore, but far enough to reverse some of the effects of aging. You can't reverse the chronology, but the biological effects kind of snap back.

They're currently testing it in the eyes of people with certain conditions, including glaucoma. Very soon there will likely be trials for skin. And some researchers at top institutions think we're going to be able to genuinely slow aging down.

One of the most exciting applications they talk about is the ovary. If you could extend the health of an ovary for an additional three years, that's huge — both for women planning families and for staving off menopause. There are also people doing interesting work with cryotherapy on ovarian tissue. We're understanding now that the ovary ages faster than the rest of the body — our organs don't age in sync — and that matters a great deal for how we experience midlife.

GLP-1s: Beyond Weight Loss

Stacy London

I've heard a lot about GLP-1s and inflammation — that people are taking microdoses specifically for inflammation. That fascinates me.

Susan Dominus

Yes. A lot of the doctors at a longevity conference I attended were microdosing themselves because they're convinced it has life-extending properties even for people who aren't obese. I wouldn't recommend it, but that's the conversation happening among researchers.

I think GLP-1s could extend average lifespan by five to seven years across the population — not per individual, but as a total effect. When you think about all the drunk driving accidents that won't happen because fewer people are drinking, all the fatty liver disease, all the heart attacks — there are so many ways people harm themselves with food, alcohol, and drugs that GLP-1s seem to genuinely temper.

And there's more. They're finding mental health benefits. ADHD effects. One longevity researcher I sat next to at the conference was not overweight, had lost maybe five or ten pounds on it, and said it had transformed his mind and body. He felt it had tamed his ADHD and had a sedative quality that reduced impulsivity across the board.

Stacy London

That fascinates me especially in the context of perimenopause and postmenopause — a high-need state where a lot of women start drinking too much because they don't know how else to cope. I was initially worried that GLP-1s were just about weight loss, and that linking them to menopause was conflating two things. But it sounds like we're really adding pieces to a bigger picture puzzle.

Susan Dominus

We are. And I think it's easy to wag your finger at people who take it. But it's very early days, and we don't have lots of long-term studies. Like hormones, many people go off of GLP-1s after a year or two — they lose the weight, they feel better, and they just don't want to be on medication indefinitely. Once it becomes a pill rather than a shot, that may change. But the pattern we see is that people struggle to stay on any medication long-term if it doesn't feel natural to them.

Closing: The Post-Menopausal Opportunity

Stacy London

All of these strides we're making — in the menopause space, in longevity research, in cellular rejuvenation — they speak to how aging is going to look completely different. The things we've always assumed about the body breaking down, we're actually starting to break through.

I've been reading lately about the grandmother theory — the idea that one of the reasons we're one of only six species that experiences menopause is because post-menopausal women are supposed to rule the world. That one really got me. We're the wise elders. Not just grandmothers — that's part of it, but not all of it.

Susan Dominus

I love that idea. I'm all in.

And you're right about the timing of it all. I've written about menopause, testosterone, hair loss in men — and now this cellular rejuvenation story, which makes you think about how radically different our experience of aging could be. The technology is moving so fast that it's genuinely hard to predict what 60 or 70 will look like for the generation coming up behind us.

‍