Longevity science is no longer confined to academic labs. It's moved into exclusive clinics, Silicon Valley biohacker circles, and the private medical protocols of people with enough money to experiment on themselves.
Bryan Johnson, the tech entrepreneur who spends over $2 million annually on his longevity protocol, has made headlines for practices that include plasma exchange, stem cell treatments, and a regiment of over 100 supplements daily. Dave Asprey, founder of Bulletproof Coffee and prominent biohacker, has openly discussed using peptides, stem cells, and experimental therapies in his pursuit of living to 180.
Here are five controversial longevity practices people are actually trying - and what you should know before considering any of them. Plus, a look at the safer, evidence-backed alternative like Ageless NMN that doesn't require a six-figure budget or a trip to an offshore clinic.
1. Young Blood Transfusions & Plasmapheresis
Let's start with the most visceral one: injecting young blood into older bodies to reverse ageing.
What it is:
Parabiosis - the practice of connecting the circulatory systems of young and old animals - has been studied since the 1950s. The results were striking: older mice showed improved muscle repair, cognitive function, and tissue regeneration when exposed to young blood.
Fast forward to today, and longevity clinics are offering variations of this concept to humans. Bryan Johnson has publicly documented his use of plasmapheresis (therapeutic plasma exchange) as part of his "Blueprint" protocol, where old blood plasma is removed and replaced with albumin. Some clinics go further, offering direct young blood transfusions from donors in their teens or twenties.
The promise:
Proponents of this wellness practice claim young blood contains growth factors, proteins, and signalling molecules that "reprogram" ageing cells, reduce inflammation, and improve vitality. The idea is that ageing isn't just about what your cells accumulate, it's also about what they lose. Young blood, theoretically, restores that loss. The cost? Upwards of $8,000 per session, often requiring multiple treatments.
2. Senolytics: Clearing "Zombie Cells"
This one actually has solid science behind it, though the methods people are using remain controversial.
What it is:
As you age, some of your cells stop dividing but don't die. They enter a state called senescence, where they linger in your tissues, secreting inflammatory molecules that damage neighbouring cells. These are often called "zombie cells" because they're neither alive nor dead, just hanging around causing problems.
Senolytics are compounds that selectively kill these senescent cells, theoretically reducing inflammation, improving tissue function, and slowing ageing.
The promise:
Early research in mice showed that clearing senescent cells extended lifespan, improved physical function, and delayed age-related decline. The logic is simple: remove the zombie cells, reduce chronic inflammation, and slow ageing.
Naturally occurring senolytics include fisetin (found in strawberries) and quercetin (found in onions and apples). Synthetic options are also being developed.
Some biohackers are self-experimenting with high-dose fisetin or quercetin protocols, often combined with fasting to amplify the effect. Others are sourcing experimental compounds through gray-market suppliers.
3. Stem Cell Injections
Stem cells are the body's master repair system. They can differentiate into almost any cell type, regenerating damaged tissue and supporting recovery. Naturally, people want to inject more of them.
What it is:
Stem cell therapy involves harvesting stem cells (either from your own body, typically bone marrow or fat tissue, or from donors) and injecting them into joints, tissues, or directly into the bloodstream. The goal is tissue regeneration, reduced inflammation, and improved recovery from injury or ageing.
Dave Asprey has documented his experiences with stem cell treatments, and Bryan Johnson's protocol includes regular stem cell assessments, though the specifics of their treatments vary.
Many "stem cell clinics" operate in regulatory gray zones, particularly outside the US. The treatments are expensive (often $5,000–$50,000), largely unregulated, and the results are inconsistent at best. Worse, there have been cases of severe complications, including infections, immune reactions, and uncontrolled cell growth.
4. Peptides: The Gray-Market Longevity Hack
Peptides are short chains of amino acids that act as signalling molecules in the body. Some of them have regenerative, anti-inflammatory, and performance-enhancing properties. And some biohackers are injecting them to slow ageing.
What it is:
Two peptides in particular have gained traction in longevity circles: BPC-157 (derived from a protein in stomach acid) and TB-500 (a synthetic version of a naturally occurring peptide called thymosin beta-4). Both are believed to accelerate tissue repair, reduce inflammation, and support recovery.
BPC-157 is particularly popular among athletes and biohackers for its purported ability to heal tendons, ligaments, and gut tissue. TB-500 is used for similar purposes, with claims of enhanced muscle recovery and reduced inflammation.
Here's the problem: these peptides are not approved for human use by any major regulatory body. Most of the research is in animals. The peptides are sold through online suppliers, often with questionable quality control, no standardisation, and zero oversight.
People are self-injecting compounds with limited human data, unknown long-term effects, and no way to verify purity or dosage accuracy.
5. Fecal Microbiota Transplants (FMT)
Yes, we're talking about poop transplants. And yes, people are doing this for longevity.
What it is:
Your gut microbiome - the trillions of bacteria living in your intestines - plays a massive role in digestion, immunity, mood, and even ageing. As you get older, your microbiome diversity declines, which is associated with inflammation, weakened immunity, and age-related decline.
Fecal microbiota transplants involve transferring stool from a young, healthy donor into an older person's gut, with the goal of "reseeding" the microbiome with beneficial bacteria.
The reality:
FMT is a legitimate medical treatment for certain gut conditions, but for longevity? The data in humans is virtually non-existent. The procedure carries risks, including infections and immune reactions. And unlike young blood or stem cells, you can't just buy this at a clinic - most FMT for anti-ageing purposes is happening through DIY biohacker communities or unregulated practitioners.
The Safer Alternative: Supporting Cellular Health from Within
Here's the pattern: most of these practices are expensive, risky, unregulated, and based on limited human data. But there's a simpler approach: supporting your body's natural cellular repair mechanisms.
One of the most well-researched pathways involves NAD+ (nicotinamide adenine dinucleotide), a molecule essential for energy production, DNA repair, and cellular function. NAD+ levels decline with age by up to 50% by the time you're 40. This decline is linked to mitochondrial dysfunction, reduced cellular energy, and accelerated ageing.
Ageless NMN is a direct precursor to NAD+, meaning it helps replenish the molecule your cells need to function optimally. Unlike experimental therapies, Ageless NMN has been studied in humans, is widely available, and doesn't require a six-figure budget or a trip to an offshore clinic.
Paired with the fundamentals, like sleep, nutrition, movement, stress management, it's one of the most evidence-backed, accessible ways to support healthy ageing without the risks of experimental interventions.
