If you have followed me for a while, you have probably noticed something. I almost never talk about supplements.
That is deliberate. For a long time, I did not think I would ever create a supplement. I spent my career in medical research, and I did not want to become one more expert borrowing a title to move product.
But I also wanted to build something that actually helped. And as I kept reading the research, one realisation became impossible to ignore. Boosting NAD⁺ alone was not enough. This formula has been on my mind ever since, in notes and in conversations with my manufacturer, for years, because if I was ever going to put my name on something, it had to survive the way I read other people's data.
But one question kept arriving, in my comments and my inbox, until I could not keep ignoring it. "Okay Marion, after everything you have learned, what do you actually take?"
This page is my answer. The short version is a formula I built myself, called Precision Longevity. The long version is everything below, including the three ingredients I refused to put in it.
It does not start in the mirror.
We picture aging as the things we can see. Lines. Grey. The face in an old photograph. But those arrive late.
It starts as something you feel, years earlier. The recovery that takes an extra day. The workout that costs more than it gives back. The afternoon wall that was not there at thirty.
That is aging too, and it begins in your thirties, inside your cells, in two jobs they never stop doing. Turning food into energy, and repairing damaged DNA. Both of them run on a single molecule called NAD⁺.
You make less of it every decade. By your forties it has dropped well below where it was at twenty, and it keeps falling. This is not a fringe idea. The decline of NAD⁺ with age is one of the most consistent findings in the entire biology of aging.
It is not only running low. It is being drained.
NAD⁺ runs on a balance. What your cells make, against what they burn through. After 40, that balance breaks.
An enzyme called CD38 climbs steeply with age and consumes NAD⁺ faster every year. And it does something worse: it also breaks down NMN, the exact raw material your body uses to rebuild NAD⁺ in the first place.
This is why taking a precursor on its own stalls. You keep pouring raw material into a tank that is draining faster than you can fill it. Almost every NAD⁺ product on the shelf is doing precisely that, and calling it enough.
Add the fuel. Then stop the drain.
That is the whole idea, and it is the reason this formula exists at all. Work both sides of the balance in a single dose.
Drives NAD⁺ synthesis back up.
Inhibits CD38, the enzyme that rises with age and destroys both NAD⁺ and NMN.
No other longevity capsule pairs an NAD⁺ precursor with a CD38 inhibitor in one dose.
Aging is not one problem. So I did not build one fix.
The mechanisms of aging are linked. Act on the right upstream levers, energy, defense and repair, and the rest follow.
So every active in here has a named job. Not one of them is present to make the label longer.
Replenishes the NAD⁺ every cell runs on, and shields it from the enzyme that drains it.
Fuels the mitochondria that turn NAD⁺ into the energy you actually use.
Calms the low-grade inflammation that quietly ages tissue over decades.
Neutralises the free radicals that wear cells down.
Drives autophagy, the cell's own self-clearing system.
Clears the aged cells that burden healthy ones, the cells that stop working but refuse to die.
Supports the repair crews that fix the damage your DNA takes every single day.
Seven levers. Eight actives. Several of them doing more than one job, which is why the list is short and the doses are not.
Two capsules. Eight actives. Nothing else.
Most blends bury small, useless amounts inside a long list. Here is every milligram, at the dose the research actually used.
One example of what that means in practice. Most formulas include spermidine at 1mg, which is fairy dusting, present on the label and absent in effect. Current clinical trials use 6mg. That is where I put it, and it is the rule for all eight.
Two clear plant-based capsules, the vegetable shell, and 942mg of actives. The pale gold is not a dye. It is the colour of the fisetin and apigenin themselves.
No magnesium stearate, nothing to pad the label. Third-party tested for heavy metals, microbial safety and label accuracy, in a GMP-certified facility. Contains: wheat (the spermidine is derived from wheat germ).
If you already take NMN on its own, this is not a correction. Single actives do exactly what they say. This is the complete system I wanted, built around one.
The hardest part was not deciding what to include.
It was deciding what to leave out.
Anyone can add ingredients. A long list looks like effort and costs nothing to print. The real discipline is in what you refuse, especially when refusing it makes the label look less impressive.
So this is the part I would actually judge a formulator on. Mine included.
Common in longevity and nootropic formulas. But a Korean study of twelve million people found a 43% higher stroke risk among users, and the mechanism behind it was confirmed in animals. At the dose most formulas use, it sits below the clinical threshold anyway. It would have made the label look smarter. It came out.
The supplement world adds this by convention, to offset a depletion people assume NMN causes. The human evidence does not show that depletion at normal doses. I do not include ingredients on convention.
The amount that would have fit sat below its effective dose. An ingredient below its clinical dose is decoration, not medicine.
Three ingredients I could have used to make the label look more impressive, and did not. That is the whole standard, and it is the one I want to be held to.
"I didn't want another NAD⁺ booster. I wanted the one I'd actually take at 40, knowing the biology: rebuild NAD⁺ with NMN, shield it from CD38, no fillers, nothing I couldn't defend in a lab. Precision Longevity is that formula, and it's on my own shelf."
Dr. Marion Gruffaz, PhDMolecular Biology, former USC researcher. Co-Founder of Solensis, which makes this, so read all of the above knowing that. It is exactly why I publish the rejections.
If you have read this far, you already understand more about this formulation than most people understand about anything they take every day.
You may decide it is not for you. That is a perfectly good outcome, and it is why I wrote all of this down instead of a headline.
But if the way I think about this makes sense to you, this is the formula I built for myself, and the one I take every morning.
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Formulated for adults 35+. If you have active cancer or are in treatment, please check with your doctor first.
90-day money-back guarantee.
Take it for a full 90 days. If you are not happy with it, we refund your purchase in full. You do not have to justify it to me.
And on what is actually in the bottle.
Every batch is third-party tested by an independent lab for heavy metals, microbial safety and label accuracy, then made in a GMP-certified facility. The certificate of analysis is published, not summarised. You can read the numbers yourself.
References
The research behind each claim on this page. Where the evidence is preclinical or preliminary, I have said so in the text above rather than here.
- NMN raises NAD⁺ in humans, dose-dependently, with a clean safety profileDose-ranging randomised trial in middle-aged adults at 300, 600 and 900mg. Huang et al., 2022.
- Long-term NMN mitigated age-associated decline in miceTwelve-month administration study. Mills KF et al., Cell Metabolism, 2016. Healthspan measures, not lifespan.
- Newer work points to longer life in female miceLong-term NMN and lifespan, sex-dependent, median lifespan +8.5% in females. 2024 preprint, not yet peer reviewed.
- NMN improved muscle insulin sensitivityYoshino M et al., Science, 2021. Prediabetic postmenopausal women only. A published comment noted uneven baseline randomisation between groups.
- NMN improved vascular function and endurance in aged miceDas A et al., Cell, 2018.
- Reduced drowsiness and improved lower-limb function in adults over 65Randomised controlled trial, 250mg daily for 12 weeks. 2022. The authors noted a placebo effect on several measures.
- Arterial stiffness in middle-aged adultsRandomised controlled trial, 250mg for 12 weeks, 2023. No significant difference overall; the signal appeared only in higher-BMI and higher-glucose subgroups.
- Alpha-GPC and stroke riskKorean national cohort, approximately 12 million people, 43% higher stroke risk among users. JAMA Network Open, 2021. TMAO mechanism confirmed in animal models.
- Apigenin inhibits CD38Preclinical only. Cell and animal work; no human randomised trial at 50mg oral. Included as mechanism, not as a promised outcome.
- Spermidine at 6mgDose selected to match current clinical trial protocols rather than conventional 1mg inclusions.