Why I'm betting on fermented protein?
We need more protein than ever to stay strong into our 90s. But whey, soy, and pea weren't built for longevity. Fermented fungal protein is. Here's why it changes everything.
👋🏼 Hi, I’m Shan. I run Xandro Lab, a longevity brand in Singapore. On Sundays I write about what I’m building, what I’m learning, and the messy process of trying to make longevity real.
Last Sunday morning I was at the National Stadium, doing my usual run on the track, and I saw something that stuck with me. A group of seniors, in their 60s or maybe early 70s, were training. Resistance bands, dumbbells, and kettle bells. And it hit me: this is what the future looks like. Not people winding down at 65, but people training at 70 so they can stay independent at 85.
My dad isn’t one of them, and I wish he was. He broke his knee with a single fall last year, and the recovery has been brutal. Not because the injury was catastrophic, but because he didn’t have the muscle mass, the bone density, or the resilience to bounce back quickly. One fall, and suddenly everything changed.
That’s the thing about aging that nobody tells you when you’re young: it’s not the big diseases that take away your independence. It’s the small falls, the loss of strength, the inability to recover. And the only way to fight that is to build your body up now: muscles, bones, metabolic resilience. So that when life throws something at you at 75 or 80, you don’t break.
If you’re in your 40s or beyond, your nutritional needs have fundamentally changed. You’re not optimizing for beach muscles in 12 weeks. You’re optimizing to be autonomous at 85. And that requires a different approach entirely.
Protein is at the center of all of this. We know now that we need significantly more protein than we thought. Close to 1.6 grams per kilogram of body weight if you’re serious about longevity. That’s not a bodybuilder target anymore. That’s a baseline for anyone who wants to stay active and autonomous into their 80s and 90s. And the reality is: food alone won’t get you there. Not consistently. Not for decades. Which is where supplementation and fortified foods come in.
But here’s the problem. Most protein options we have today (whey isolate, pea protein, soy protein) weren’t designed for people in their 40s, 50s, 60s who are planning to live actively into their 90s. They were designed for gym performance in your 20s, or plant-based diets, or cost efficiency. None of them were built with the assumption that you’d be using them to maintain muscle, support autophagy, feed your gut microbiome, and stay metabolically healthy for the next 40-50 years.
And here’s something most people don’t realize: modern diets are catastrophically low in fiber. The average person gets maybe 10-15 grams of fiber a day when they need 25-35 grams. Fiber isn’t just about digestion. It’s about feeding the gut bacteria that regulate inflammation, produce neurotransmitters, support immunity, and even influence how well you age. Protein powders strip fiber out completely to hit high protein percentages. With protein powders, you’re solving one problem (protein intake) while ignoring another (fiber deficiency).
That’s why I’m betting on fermented fungal protein. It’s the first protein source actually designed for longevity. It delivers complete protein, yes, but it also delivers fiber, naturally occurring spermidine, and prebiotic effects that support gut health. It’s not trying to replace whey for a 25-year-old powerlifter. It’s built for someone in their 40s, 50s, or 60s who wants to be training with resistance bands at 70 and still traveling independently at 85.
This isn’t a product pitch. It’s an explainer on why fermented protein is different, what the alternatives look like, and why I believe this is the future of protein supplementation for people optimizing for healthspan, not just muscle mass.
Today’s Reading:
The landscape: what we’ve been working with (soy, pea, whey, clear whey)
Why none of them were built for longevity
Fermented fungal protein: what makes it different
The comparison: how different proteins stack up
Why fortification makes more sense with fermented protein as the base
1. The Landscape: What We’ve Been Working With
If you scroll through protein options online, you’ll see the usual suspects: soy protein, pea protein, whey isolate, whey concentrate, and more recently, clear whey protein. Each of these has its place, and each came about for specific reasons. But none of them were designed with longevity in mind.
Soy protein was one of the first plant-based complete proteins to hit the market. Complete, meaning it has all nine essential amino acids your body can’t make on its own. For a long time, soy was the go-to for vegetarians and people avoiding dairy. But then the phytoestrogen debate happened. Concerns about soy’s estrogen-like compounds and whether they’d mess with hormones, particularly in men. The science has mostly settled (it’s fine for most people in reasonable amounts), but the reputation never fully recovered.
Pea protein became the darling of the plant-based movement over the last decade. It’s hypoallergenic, it’s sustainable, and it doesn’t carry the baggage that soy does. But here’s the problem: pea protein is low in methionine, one of the essential amino acids. To get around this, most brands blend pea with rice protein or other sources to balance out the amino acid profile. It works, but you’re already starting from a position of incompleteness. And beyond that, pea protein tends to be lower in leucine, the specific amino acid that triggers muscle protein synthesis.
Then you’ve got whey protein, the gold standard for decades. Whey isolate, in particular, became the default for anyone serious about building muscle. It’s a complete protein, it’s high in leucine, it absorbs quickly, and it’s been studied extensively. Bodybuilders loved it. Athletes loved it. And for good reason: if your goal is anabolic response (muscle building), whey delivers.
But here’s what whey doesn’t deliver: anything beyond protein. No fiber. No longevity compounds. No support for your gut microbiome. Whey was built for one thing: getting amino acids into your bloodstream fast so your muscles can recover and grow. If you’re 25 and training hard, that’s perfect. But if you’re 55 and trying to build a body that stays resilient for the next 40 years, whey is just one piece of a much bigger puzzle. And it’s a piece that doesn’t address metabolic health, autophagy, or the gut-brain axis. All of which matter more as you age.
Whey concentrate is similar to isolate but less filtered, so it has more lactose, fat, and sometimes a bit more bioactive compounds. Some people prefer it because it’s less processed, but for anyone lactose-intolerant, it’s a non-starter. Clear whey protein is just whey isolate that’s been hydrolyzed (pre-digested) so it doesn’t turn thick and milky when you mix it with water. It’s basically whey isolate repackaged for people who hate the texture of traditional protein shakes. Still whey. Still limited to muscle. Still missing everything else.
So here’s where we are: the plant-based options (soy, pea) have incomplete or suboptimal amino acid profiles and need blending or fortification to compete. The dairy-based options (whey) are great for muscle protein synthesis but terrible for everything else that longevity demands. None of these were designed with the assumption that the person drinking them wants to be independent and active at 90. They were designed for short-term goals: muscle gain, plant-based diets, quick recovery.
And that’s the gap fermented protein fills.
2. Fermented Fungal Protein: What Makes It Different
Fermented fungal protein (also called mycoprotein) comes from fermenting specific strains of fungi. Products like Quorn use Fusarium venenatum. Newer proprietary strains are being developed for protein powders. The fermentation process is what makes this different from every other protein source on the market.
Here’s why it matters.
It’s a complete protein with high bioavailability. Fermented fungal protein delivers all nine essential amino acids. In terms of digestibility and amino acid quality, it scores 98-102% on the DIAAR% scale. That puts it well above pea protein (77%) and soy protein (87%), though still below whey isolate (115%). The fermentation process partially breaks down the protein structures during production, which makes it easier to digest and absorb. For older adults (whose digestive efficiency naturally declines) this is a real advantage. And this isn’t just marketing talk. There’s actual research backing this up, with ongoing clinical trials measuring digestibility, metabolic response, and even how it affects satiety hormones and blood glucose.
It’s naturally high in spermidine. This is the killer differentiator, and the main reason I’m so bullish on fermented protein. Spermidine is one of the few key compounds with longevity research behind it. It induces autophagy, the process where your cells clean out damaged components and recycle them. It supports cardiovascular health, cognitive function, and has been associated with populations that live exceptionally long lives.
Here’s the thing: whey has zero spermidine. Pea protein has zero spermidine. Soy has trace amounts at best. The only foods naturally high in spermidine are fermented foods: natto, aged cheese, mushrooms, wheat germ. Because fermentation is what creates it. Fermented fungal protein concentrates this naturally. The minimum spermidine content in Fermotein (produced from Rhizomucor pusillus fungus) is 160mg per 100 grams of powder. For perspective, our standalone spermidine product is 10mg per serving.
To put that in perspective: wheat germ has about 15mg per 100g. Natto has 10-50mg per 100g. Fermented protein has 160mg per 100g minimum. That’s 3-16 times higher than the next best natural food sources. When you’re taking a serving to get 30 grams of protein (about 82 grams of powder), you’re getting roughly 131mg of spermidine. Studies on spermidine supplementation typically use 5-15mg per day and show measurable benefits. You’re getting 10-25 times that dose just from your protein shake. (Yes, this could be a concern and this dosage has been tested for safety.)
You’re not adding spermidine as a supplement afterward. It’s intrinsic to the protein source itself. That’s a fundamentally different product.
It has fiber. Most protein powders strip out fiber to hit high protein percentages. The goal is usually to get 80-90% protein by weight, which means removing everything else. But fermented fungal protein keeps fiber intact because fungi have cell walls made of chitin and beta-glucans. These are complex fibers that your gut bacteria thrive on. Fermented protein contains 30% fiber by weight. That’s 30 grams of fiber per 100 grams of powder.
Of that 30 grams, roughly half (about 15 grams) is chitin and chitosan, which have been shown to support cholesterol management and have prebiotic properties. The rest includes beta-glucans (about 0.3 grams) and other beneficial fibers (about 14.7 grams). This combination feeds beneficial gut bacteria, helps regulate blood sugar, and contributes significantly to your daily fiber intake.
The average person gets 10-15 grams of fiber a day when they need 25-35 grams. A single serving of fermented protein (around 82 grams to get 30 grams of protein) delivers about 24.6 grams of fiber. That’s almost your entire daily requirement in one scoop. Whey and other proteins don’t do that. This is complete protein plus fiber for longevity.
It’s sustainable and scalable. This isn’t the main argument, but it’s worth mentioning. Fermentation is far more resource-efficient than dairy farming or large-scale pea agriculture. You don’t need massive tracts of land, you don’t need livestock, and the production cycle is measured in days, not months. As the world ages and protein demand increases (and it will, because everyone’s going to realize they need 1.6g/kg to stay functional), fermented protein is one of the few sources that can actually scale without destroying the environment.
It’s built for longevity, not just muscle. This is where everything comes together. Whey was optimized for anabolic response, getting amino acids into muscles fast. Pea protein was optimized for plant-based diets. Fermented fungal protein is the first one optimized for healthspan. Muscle, yes. But also autophagy, gut health, metabolic function, and cellular resilience. If your goal is to be independent and active at 85, you need spermidine to keep your cells cleaning themselves out. You need fiber to keep your gut microbiome healthy, because gut health affects everything from immunity to brain function. You need a protein source that works with your biology as it ages, not just against muscle breakdown.
That’s what fermented protein does. It’s not a replacement for whey or pea protein in the traditional sense. It’s a different category entirely.
3. The Technical Case: Why Fermented Protein Wins
Let me break down the technical advantages more specifically. This isn’t just marketing talk. There are real biochemical reasons why fermented fungal protein outperforms the alternatives when your goal is longevity.
Amino acid profile and leucine content: Fermented fungal protein has a complete amino acid profile, but let’s be honest about where it stands. Whey isolate still has the edge on leucine content and overall DIAAR% score (115% vs fermented protein’s 98-102%). Leucine is the amino acid that activates mTOR, the pathway responsible for muscle protein synthesis. It’s especially important for older adults because they experience something called anabolic resistance. Their muscles don’t respond to protein as efficiently as they used to. You need higher leucine intake to get the same muscle-building effect.
So if your only goal is maximum muscle protein synthesis per gram of powder, whey still wins. But here’s what the DIAAR% scores tell us: fermented protein is significantly better than pea protein (77%) and soy protein (87%) at delivering usable amino acids. And more importantly, it delivers that protein alongside everything else: the spermidine, the fiber, the prebiotic effects. Whey gives you protein and nothing else. Fermented protein gives you slightly less efficient protein delivery but compensates with compounds that whey can’t provide at all.
Spermidine concentration: The spermidine levels in fermented fungal protein are significantly higher than in any other protein source. The minimum guaranteed content is 160mg per 100g of powder (1600mg/kg). When you take a serving to get 30 grams of protein (about 82 grams of powder), you’re getting approximately 131mg of spermidine.
Fiber and gut health: The fiber content in fermented fungal protein is 30% by weight. That’s 30 grams per 100 grams of powder. Of this, approximately 15 grams is chitin and chitosan (powerful prebiotics that support cholesterol management), about 0.3 grams is beta-glucans (known for immune support), and the remaining 14.7 grams consists of other beneficial fibers. All of these are prebiotic, meaning they feed beneficial gut bacteria.
There’s growing evidence that gut health influences everything from immune function to mental health to metabolic regulation. Most protein powders ignore this completely. They strip fiber out to maximize protein percentage. Fermented protein integrates it by default. When you take a serving to get 30 grams of protein (82 grams of powder), you’re also getting about 24.6 grams of fiber. For context, that’s more fiber than the average person consumes in an entire day, and it’s approaching the full daily recommended intake of 25-35 grams.
You’re not just building muscle. You’re supporting the microbiome that regulates inflammation, nutrient absorption, and even neurotransmitter production. For someone in their 50s, 60s, or 70s, that’s critical. Gut dysbiosis (imbalanced gut bacteria) is linked to frailty, cognitive decline, and metabolic dysfunction. Fermented protein works against that. Research has shown that the chitin and chitosan in fermented protein can increase short-chain fatty acid production and promote the growth of beneficial Bacteroides species. These species play important roles in fiber fermentation and even produce polyamines like spermidine.
Digestibility for aging populations: As you age, your digestive enzymes become less efficient. Protein that’s harder to break down just passes through without being absorbed. Fermentation pre-digests some of the protein structures, which makes fermented fungal protein easier on the digestive system. Older adults often struggle with whey or plant proteins because they cause bloating, gas, or just don’t digest well. Fermented protein bypasses a lot of that because the fermentation process has already done part of the work your gut would normally have to do.
This isn’t just theoretical. In vitro studies have shown that fermented protein has good digestibility. Better than soy and pea, scoring 98-102% on the DIAAR% scale compared to whey’s 115%. Human clinical trials are currently underway examining post-prandial glucose and insulin response, GLP-1 response (the satiety hormone that’s become famous because of drugs like Ozempic), and spermidine levels in blood after consumption. Early indications suggest that fermented protein doesn’t just deliver protein. It has favorable metabolic effects that go beyond what whey or plant proteins can offer.
There’s also emerging research on fermented protein’s prebiotic effects, specifically looking at how it influences short-chain fatty acid production and microbiome composition through ex-vivo intestinal tissue models, which simulate how the protein interacts with your gut lining and microbiome.
No allergens or intolerances: Fermented fungal protein is naturally free of lactose, soy, and common allergens. Whey isolate is low in lactose but not zero. Soy has the phytoestrogen issue (real or perceived). Pea protein is generally fine, but some people find it hard to digest. Fermented protein sidesteps all of that. It’s hypoallergenic by nature, which makes it accessible to a wider population.
The protein content trade-off: Here’s something I need to be honest about. Whey isolate contains 82.9% true protein (measured by amino acids). Soy and pea protein isolates are around 64-67% true protein. Fermented fungal protein sits at 36.6% true protein by weight. That’s significantly lower. Why? Because fermented protein retains the fiber (30%), beta-glucans, chitosan, vitamins, minerals, and other compounds that come from the fungal biomass. You’re getting less concentrated protein, but you’re getting significantly more of everything else.
What this means practically: if you’re trying to hit 30 grams of protein in a serving, you’ll need about 82 grams of fermented protein powder versus 36 grams of whey isolate. The serving size is 2.3 times larger. The cost per gram of protein is higher. This is a real limitation. It’s why fermented protein won’t replace whey for someone in their 20s whose only goal is cheap, efficient protein delivery for muscle building.
But if you’re in your 40s, 50s, or 60s, and your goal is longevity, the calculation changes. Muscle maintenance plus autophagy plus gut health plus fiber intake plus metabolic support. That 36.6% protein content isn’t a bug, it’s a feature. You’re choosing to take in less concentrated protein in exchange for a more complete nutritional intervention. That 82-gram serving gives you 30g protein, 24.6g fiber (almost your entire daily requirement), and 131mg spermidine (10-25 times the studied dose). It’s a different calculation entirely when you’re optimizing for independence at 85, not aesthetics at 25.
4. The Comparison: How Different Proteins Stack Up
Here’s how the major protein sources compare across the metrics that actually matter for longevity:
When you look at it this way, the difference becomes clear. If you're in your 20s or 30s and optimizing purely for protein delivery efficiency and muscle building, whey isolate still wins: higher protein percentage, better DIAAR% score, smaller serving size, lower cost per gram. But if you're 40 and beyond, fermented fungal protein is the only option designed from the ground up to support the biological systems that determine whether you're independent and functional at 85.
5. Why Fortification Makes More Sense with Fermented Protein
One of the things I’ve been thinking about a lot is fortification. The idea that daily foods and supplements should be fortified with specific compounds to meet the health goals of this generation. We’re not dying at 50 anymore. We’re living into our 80s and 90s, and we want to be active and independent during those years. That requires a different nutritional baseline than what traditional food provides.
Fortification isn’t a new concept. We’ve been fortifying milk with vitamin D, flour with folic acid, and salt with iodine for decades. But what’s changing now is that we’re starting to fortify for performance and longevity, not just to prevent deficiency diseases. We’re adding creatine for muscle and cognitive function. TMG (trimethylglycine) for methylation and heart health. Vitamin B12 for energy and neurological health. Vitamin D3 and K2 for bone density and calcium regulation.
The question is: what’s the best base to fortify? And I think fermented fungal protein is the answer, for a few reasons.
It already contains longevity compounds. Unlike whey or pea protein, which are nutritionally one-dimensional, fermented protein comes with spermidine and fiber built in. When you add creatine, TMG, B12, D3, and K2 on top of that, you’re not just cramming random ingredients into a powder. You’re stacking synergistic compounds that work together. Spermidine supports autophagy. Creatine supports cellular energy and muscle. TMG supports methylation pathways that decline with age. B12 supports mitochondrial function and nerve health. D3 and K2 work together to regulate calcium and bone density. These aren’t isolated ingredients. They’re part of a system. And fermented protein is the perfect scaffold for that system because it’s already aligned with longevity, not just muscle.
It turns supplementation into a protocol, not a product. I’ve written before about how longevity isn’t about individual ingredients. It’s about protocols. Blends that address multiple pathways at once. Fermented protein, fortified with the right compounds, becomes more than just a protein shake. It becomes a daily intervention that supports muscle, bones, cognition, cellular cleanup, and metabolic health all at once. That’s what people actually need. Not five different supplements they have to remember to take. One thing, every morning, that covers the bases.
It’s easier to justify the cost. Let’s be honest: fermented protein is going to be more expensive than whey or pea protein, at least in the short term, because the production is newer and less commoditized. But if you’re getting protein, spermidine, fiber, creatine, TMG, B12, D3, and K2 in one serving, the cost per nutrient is actually competitive.
This is where I think the market is headed. Not just protein powders, but fortified protein protocols that are designed around the assumption that people want to stay independent and active into their 90s. Fermented fungal protein is the only base that makes sense for that, because it’s the only one that’s already built around longevity from the ground up.
6. Closing: Why I’m All In
I started Xandro because I wanted to build something that actually helps people live longer, better lives. Not just extend lifespan, but extend healthspan. The years where you’re strong, sharp, independent, and able to do the things you love. And the more I learn, the more convinced I am that fermented fungal protein is going to be at the center of that.
Not because it’s trendy. Not because it’s novel. But because it’s the first protein source actually designed for people in their 40s, 50s, and 60s who are planning to stay active into their 80s and 90s. Whey was designed for 25-year-old bodybuilders chasing muscle gains. Pea protein was designed for plant-based eaters avoiding dairy. Fermented protein is designed for people who want to be at the track at 70, training with resistance bands, still independent, still strong, still metabolically healthy.
I think about my dad and his broken knee. I think about those seniors I saw last Sunday at the National Stadium. I think about what I want my own 80s and 90s to look like. And I don’t think whey isolate is going to get me there. Whey gives me protein, but it doesn’t give me the fiber my gut needs, the spermidine my cells need for autophagy, or the prebiotic support my microbiome needs. I don’t think pea protein is going to get me there either. It’s incomplete, lower quality, and still missing everything beyond basic amino acids.
Fermented protein might. Not on its own. Nothing works on its own. But as part of a larger protocol that includes strength training, sleep, recovery, stress management, and the right nutritional foundation, I believe fermented protein is the piece that ties it all together. Complete protein plus fiber for longevity. Not just muscle maintenance, but cellular health, gut health, metabolic health, all delivered in one daily intervention.
That’s why I’m betting on it. That’s why we’re building it. And that’s why I think, five or ten years from now, this is going to be the standard for the 40+ crowd. Not whey, not pea, but fermented fungal protein fortified with the compounds that actually support healthspan.
We’re just at the beginning of this. The production is still being refined (we’re using Rhizomucor pusillus fungus through a patented fermentation process). The research is still emerging. The market is still figuring out what this even is. But I’d rather be early on something that makes sense for the next 40-50 years of my life than late on something that was designed for someone half my age with completely different goals.
Fermented protein isn’t just better protein. It’s complete protein plus fiber, designed for longevity, built for people who understand that independence at 85 is built in your 40s, 50s, and 60s.
Author’s Note: This piece was written with the assistance of AI, using data from the manufacturer and publicly available research. The opinions and positioning expressed are entirely my own.
👋🏼 Until next Sunday
— Shan