Anti-Aging Powers of Spermidine: Nature’s Fountain of Youth | Leslie Kenny

The Longevity & Lifestyle podcast

The Longevity & Lifestyle podcast

The Longevity & Lifestyle podcast

Episode 118

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Performance coach, detail-loving educator, big-thinking entrepreneur, podcaster, mama, passionate adventurer, and health optimization activist here to help people transform their lives, and reach their highest potential! All rolled into one.

“Spermidine is a fasting mimetic. So people who either don't want to go through fasting or who shouldn't do fasting can unlock the benefits of autophagy by using spermidine to activate it without the negative side effects.” - Leslie Kenny

There is a natural compound that is present in sperm, human breast milk, and in the endosperm of seeds.

In all these cases, it is there to help the next generation survive and thrive. 

This compound is called spermidine, and it works wonders for longevity and health. 

Today’s return guest Leslie Kenny is here to tell us all about it! 

Leslie is a graduate of both Berkeley and Harvard and the founder of Oxford Healthspan. 

She was diagnosed with lupus and rheumatoid arthritis in her 30s, and her prognosis was terrible. However, instead of listening to the doctors and giving up, she went on a journey of healing and discovery. 

Today, at 57, she is living proof that we have much more control over our health than we think. And she attributes much of her success to spermidine. 

So without further ado, let’s dive right into the healing powers of this amazing natural compound. 

Tune in! 


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Show Notes - Keywords

How Spermidine helps increase longevity, Using Spermidine for grey hair and improving hair health, The effects of Spermidine on female hormone health, how Spermidine helps sleep, recent research on spermidine and its effects. 


Intro (00:00)
What is spermidine, and how does it increase longevity? (02:04)
The effects of spermidine on grey hair and hair health (06:12)
Female hormone health and spermidine (16:49)
Spermidine supplementation for sleep problems (22:12)
Best practices for spermidine supplementation and different types of spermidine supplements (26:13) 
Research around spermidine (36:44)
When does our natural spermidine production decrease (41:01)
The Oxford Longevity Project (43:44)
Leslie on longevity (47:56)
Outro (53:22)


Intro (00:00)
What is spermidine, and how does it increase longevity? (01:23)
The effects of spermidine on grey hair and hair health (05:31)
Female hormone health and spermidine (16:08)
Spermidine supplementation for sleep problems (21:32)
Best practices for spermidine supplementation and different types of spermidine supplements (25:33) 
Research around spermidine (36:10)
When does our natural spermidine production decrease (40:23)
The Oxford Longevity Project (43:05)
Leslie on longevity (47:17)
Outro (53:41)


“Think of a cell as a hoarder, a hoarder of old things that no longer work well. Think of autophagy as your own Marie Kondo that goes in and sparks joy by getting rid of the clutter. Salvaging things that might be reused in a new organel or mitochondria or stem cell. But then burning the rest. When you burn that rubbish, you create energy. This is what happens when we fast.” - Leslie Kenny

“Spermidine is a fasting mimetic. So people who either don't want to go through fasting or who shouldn't do fasting can unlock the benefits of autophagy by using spermidine to activate it without the negative side effects.” - Leslie Kenny

“If you’re in middle age and don’t get enough deep sleep, the chances of getting alzhiemers and dementia later in life are much higher.” - Leslie Kenny

“People who take spermidine notice that their hair, skin and nails all grow faster. They have to cut their nails more frequently, they have to cut their hair more frequently, and their skin seems to repair faster. If you get a cut, the wounds tend to heal quicker.” - Leslie Kenny

“Spermidine inhibits 9 of the 12 hallmarks of ageing. These are the pathways down which we age” - Leslie Kenny

Legal Disclaimer: Please note, to avoid any unnecessary headaches, Longevity & Lifestyle LLC owns the copyright in and to all content in and transcripts of The Longevity & Lifestyle Podcast, with all rights reserved, as well as the right of publicity. You are welcome to share parts of the transcript (up to 500 words) in other media (such as press articles, blogs, social media accounts, etc.) for non-commercial use which must also include attribution to “The Longevity & Lifestyle Podcast” with a link back to the URL. It is prohibited to use any portion of the podcast content, names or images for any commercial purposes in digital or non-digital outlets to promote you or another’s products or services.


Claudia von Boeselager: Welcome to another episode of the Longevity and Lifestyle Podcast. I'm your host, Claudia von Boeselager. I'm here to uncover the groundbreaking strategies, tools, and practices from the world's pioneering experts to help you live your best and reach your fullest potential. Don't forget to subscribe to the podcast to always catch the latest episodes.

Legal Disclaimer: Please note, to avoid any unnecessary headaches, Longevity & Lifestyle LLC owns the copyright in and to all content in and transcripts of The Longevity & Lifestyle Podcast, with all rights reserved, as well as the right of publicity. You are welcome to share parts of the transcript (up to 500 words) in other media (such as press articles, blogs, social media accounts, etc.) for non-commercial use which must also include attribution to “The Longevity & Lifestyle Podcast” with a link back to the URL. It is prohibited to use any portion of the podcast content, names or images for any commercial purposes in digital or non-digital outlets to promote you or another’s products or services.


Leslie Kenny 0:00  
spermidine helps with female germline stem cells. These are the cells that you need for egg production for older women looking to get pregnant. It looks like these poly aims are supportive of fertility.

Claudia von Boeselager 0:17  
Are you ready to boost your longevity and unlock peak performance welcome to the Longevity and Lifestyle Podcast I'm your host Claudia von Boeselager, longevity and peak performance coach. Each week we'll explore groundbreaking science, unravel longevity secrets share strategies to grow younger and stay up to date with world-class health and peak performance pioneers. Everything you need to live longer, live better, and reach your fullest potential ready to defy aging, optimize health, and promote peak performance; visit For more, my returning guest today is Leslie Kenny, founder of Oxford Healthspan and co-founder of the nonprofit Oxford Longevity Project. And bulletproof coach Leslie is a Southern California entrepreneur and graduate of both Berkeley and Harvard whose life was turned upside down when she was diagnosed with lupus and rheumatoid arthritis in her 30s. This led her down the path to healing, and she discovered and learned about a natural compound called spermidine, abundant in Natto, which I'm probably pronouncing wrong because it's a traditional Japanese dish that she grew up with spermidine shows great promise in supporting health as we age today at 57. Leslie is living proof that we can get better with age so long as we take responsibility for our health and meet our doctors halfway. Welcome back to the Longevity and Lifestyle Podcast. Leslie, it’s such a pleasure to see you here again. 

Leslie Kenny 1:51  
Thank you so much for inviting me again, Claudia, and you did pronounce natto perfectly

Claudia von Boeselager 1:56  
 or did I Okay? Japanese is not very profound, Mandarin Chinese, but that's about it. Let's see, I'd love to start with for those who may have missed our previous episode, and because you're such an expert in this and it's so important for longevity, what exactly is protein, and how does spermidine help increase longevity? 

Leslie Kenny 2:18  
Well, spermidine is one of a class of poly Amiens, Polyamiens are just molecules made from amino acids, in this case from arginine and ornithine with a little Sammy threw in, and it is joined in nature by some other poly AIMIM, spermine, and putrescine. And the three together seem to be present in high quantities in things like sperm, or semen, human breast milk, and in the endosperm of seeds. In all these cases, they are there to help the next generation survive and thrive. It's so important for us as humans that we actually manufacture it in our tissues. But our gut biome, those healthy beneficial bacteria that make things like B-vitamin and serotonin, can also make spermidine as well. And we can also get it from plants. Now when we're young, if we eat a lot of junk and we don't eat a lot of plants where it is found in abundance, we can manage because the body has this ability to manufacture it in those two places, tissues and the gut biome. But as we get older, variability to produce this declines, and we do need to increase our intake from plants. Now you asked why it helps with longevity. And it is because it inhibits nine of the 12 hallmarks of aging. These are the pathways down which we age, and they include many things that your followers will already know about. So let's say dysfunctional stem cells or impaired mitochondrial function, gut dysbiosis inflammation these are four of the hallmarks of aging that spermidine inhibits or slows down. But it also helps with something called impaired autophagy. autophagy is a fancy word for cell renewal it means in Greek self-eating, so think of it as self-cleaning of the cells, constantly rejuvenating the cells so that they are like new again. And as we get older, that process becomes less and less good, which means the cells accumulate more and more rubbish. If you think of this cell as a hoarder, and a hoarder of, you know, old things that no longer work well. Think of a toffee G as your cell's own Marie Kondo that goes in and sparks joy by getting rid of the clutter. Looking for things salvaging things that might be reused in a new organelle, or mitochondria, or stem cell, but then burning the rest. And when you burn that rubbish, you create energy. And this is what happens when we fast. So we fast, the body has no food and says, right, I need energy. How am I going to do this? It looks around in the cells and says, Oh, I see rubbish in the cells; let's burn that. And it does. And it's that's how the body unlocks energy in a fasted state. So you can fast to activate autophagy. But spermidine is a fasting mimetic. So for those people who either don't want to have to go through fasting, or who shouldn't do fasting, let's say women in their reproductive years, or, you know, older people who have sarcopenia, or muscle wasting, who don't have a lot of body fat to burn, or people who are hypothyroid, these individuals should not be fasting. And for them to unlock the benefits of autophagy, they can use something like spermidine to activate it without the negative side effects.

Claudia von Boeselager 6:12  
That is beautifully said, so thank you for summarising that. Let's talk about some specific benefits also around the hair. So a lot of people worry about grey hair; I know that this is a very big thing. So can you talk about the benefits of spermidine for hair specifically and helping with grey hair? 

Leslie Kenny 6:33  
Well, so the benefits that I just mentioned, the hallmarks of aging, those benefits are slowing, those are things that are inside the body, and we don't, we can't actually see the cells looking cleaner or functioning better. But areas of the body that have high cell turnover include Hair, Skin, and Nails. Now, inside the body, our gut lining, which is only one cell thick, also has very high cell turnover and replaces every 72 hours. But we can say that the hair, skin, and nails that are constantly sloughing off and being replaced are, in a way, I'll say this as a nonscientist, a bit of a proxy for what's going on in the gut. And if you take spermidine, Most people notice that their hair, skin, and nails all grow faster. In particular, their nails have to be cut them more frequently, they noticed that their hair needs to be cut more frequently. And their skin seems to repair faster. If you get a cut, the wounds tend to heal. Now, all of these things have been supported in the lab in mouse studies, in some cases, in human studies. So let's talk about hair, which is specifically pointed out. There have been studies done in vitro. So in a petri dish, they have taken scalp tissue from people who were undergoing plastic surgery facelift and where some of the hair at the hairline was actually cut away. And they put that into a petri dish, and then they exposed it to spermidine. And they could see that within six days. Something like between 25 and 30% of the hair that was in what is called the telogen, or the shedding phase, had moved back into the antigen or growth phase. So why is that? Why does that matter? Well, the growth phase is the only time when the pigment is produced. That's called melanogenesis. So when melanin is made, and it also we want those of us who are older, so I'll be 58. And just a few more weeks, I can't believe it. But as you get older, one of the things you notice is that it's a little bit harder to grow your hair longer. And that's because it just doesn't stay in that antigen or growth phase very long. And this is why women, as they get older, will do things like I need to get hair extensions, or, you know, they do other things to kind of match the fact that it is harder to grow your hair longer. But if we can keep the follicle the hair follicle in that growth phase, then we do have the opportunity for those individual strands of hair to eat elongate as well as pigment. So we have had, you know, people who have experienced pigmentation, and it doesn't really matter what your age is. It what it really depends on is your status, your spermidine status, and I think I've shown you this photo before I don't know how many people are going to be watching this on YouTube or someplace else. This photo shows a 79-year-old woman who had been on the product for about five months when she began to get this stripe at the root of her hairline, And it began to get dark again. And that was so unusual during COVID. To see women with their roots dark and the ends white. It was usually the other way around. 

Claudia von Boeselager 10:11  
Yeah. So if I can just interrupt you for a second for people listening who haven't seen it. So it was just an image of this lady's forehead with short hair, the tips of which are grey, but the roots are actually dark. So it's like a reverse greying, if you will, because the hair is regrowing with the Pete, the original pigmentation, the original color of the hair. So really exciting. 

Leslie Kenny 10:35  
Yeah, so so that was exciting. We've also had, we have a 9192, maybe now, your old client who had always been white-haired but had lost all the hair on the top of his head. So how to kind of fryers, you know, one of those fryers Papes. And he began to regrow hair on top, which actually he didn't like because it was very stuck straight up. But of course, it has to do that before it gets long enough to sort of live flat again. But he also began to get dark hairs. Now it wasn't all the way across the head that he was getting darker. And what surprised him and his wife was that he was getting sort of clumps of dark hair, which was so strange, because he says that he hasn't had this color of hair for over 50 years. Wow. So that's why I say it's not impossible to have results even if you're older. And it really does. It depends not just on spermidine status size. I know I said that earlier. It's not just that it's multifactorial grey hair is a multifactorial problem; there are many root causes of it. Low spermidine Low sperm main content, they're just, you know that there's low poly, Amiens is just one factor could also be low iron, low copper, low B vitamins. Poor thyroid function, I think thyroid function is it is a major culprit of hair loss, and premature grain could simply be stress. You can have a chronic infection as well, which causes the body to do whatever it can to swarm that virus or that pathogen. One of those things that it produces is hydrogen peroxide. So to kill off a pathogen, it will create hydrogen peroxide in the body. And then what does the body do with that? Well, normally, it uses glutathione, catalase, or superoxide dismutase. These are all three detoxifiers that the liver makes, they'll use one of those three to neutralize the hydrogen peroxide, and then it converts them to harmless water. But if your liver function isn't great, if you are, let's say, under a lot of stress, you might be smoking, you might be drinking to relax, you might be eating a high-sugar diet, and you might not be getting enough sleep. All of these things are reasons that there are things that we can production of those detoxifiers or that deplete the liver of those detoxifiers. And then you don't have enough to neutralize the hydrogen peroxide. So your hair turns white literally from the inside out with that internal bleaching. And that's, you know, just to give you an idea of all the different ways that people go grey, you know, that's, that's a variety of the reasons I'm not, you know, I'm not going to say that you take more spermidine and spermine to help, but it's certainly not going to hurt and in some cases, if all the other things are in balance and you're just missing this one puzzle piece, then you do have the opportunity to re pigment and grow the hair longer. 

Claudia von Boeselager 14:04  
What is the recommended dose for that? So for somebody listening who may be for men that might be going bold and be like okay, let me get on top of or but even for women are saying, you know, I was noticing the grey hairs, or I have a lot of grey hair. What is the recommended dose? 

Leslie Kenny 14:19  
Well, so that's a really tricky one what we do so everybody's dose is going to depend on their individual need. We have human trials from memory and cognition where we know that one milligram of spermidine Daily Dose improves cognition. So we know that that's on the memory side for her nobody's actually done that study saying what the standardized dose that is going to improve or re-pigment is. What we do know is that in the case of, let's say, Alopecia Areata, there's this study that came out of Korea called altered poly aiming profiling in the hair of patients with androgenic, alopecia, and alopecia. And they simply were looking at the amount of these poly aims in the body of different people with these two conditions. And they noticed that those who had, who had a lot of this alopecia, had very low poly AIMIM status. So all I can say when it comes to both pigmentation and improving hair growth, increase the amount of spermidine and spermine that you take in from food sources and supplementation. And then see, you know, see how you do you can because these are food derived, you can simply increase the amounts, you can get it from short hockey mushrooms from peas, or you can get it from a, you know, a food derived supplement, such as the one that my company Oxford healthspan makes. And you can, you know, you can double up triple up to see, you know, is it making an impact. Most people will notice the growth of new baby hairs within about six to eight weeks. 

Claudia von Boeselager 16:16  
Yeah, when I was using them as well. I noticed the baby hairs sticking up. I thought because I have long hair, I can imagine your 92-year-old client was kind of wondering about the hair sticking up, but with longer hair, I can kind of 

Leslie Kenny 16:31  
Yeah, yeah, for those who have gone completely bald, it is it's uh, you know, I'm not sure that they love it because it's fuzzy. Right? Yeah, but that is kind of how it starts. So yeah, 

Claudia von Boeselager 16:45  
exactly. The baseball cap at the beginning, and then yeah, yeah, let's talk about female hormone health, such an important area, and the effects spermidine has on female hormone health. 

Leslie Kenny 16:57  
So there was a great study that was done in Canada several years ago, which used a higher dose, so in this case, we do know the dose was five milligrams, and they took five milligrams of spermidine, and they used, they also had spermine in there as well. And that's the same as our Primatene original product. And the reduction in salivary cortisol levels in both men and women decreased by 58% in 30 days; that's a reality that's a lot. So why do we care about cortisol? Cortisol is a hormone that is manufactured in the body in response to daylight. So when we wake up, are the photoreceptors in their eyes that have nothing to do with sight but simply light entrainment, they say, Oh, I noticed there's light. Now make cortisol, cortisol allows us to stand up so we don't fall over and hurt ourselves. It gives us, you know, it will raise the blood pressure; it just allows us to also deal with any predators that might be out there during the daylight. Now, as the day progresses, let's say by four o'clock as we're getting towards dusk, your cortisol production should drop, and the body begins to produce melatonin, right so that we can run that glide path to sleep. If, however, we are exposed to blue spectrum light and light bulbs or digital devices or mobile phones, then those photoreceptors say, Oh, I made a mistake. It's actually daylight that keeps producing cortisol. Now, cortisol is made from progesterone. And progesterone is something that both men and women need to help keep it keeps us calm. In women, it helps with the lining of the endometrium to make it ready for implantation of the egg. But it's an anti-anxiolytic. It also helps with sleep. Now, as we women go towards menopause, we often have dual responsibilities, teenagers at homework, and we've got our aging parents. And we tend to give give give give just exactly the time that our progesterone is beginning to decline anyway. But we stay up, we push ourselves, we continue to have that chronic production of cortisol, and we even rub our progesterone stories even more, which is terrible. So having spermidine and spermine together decrease. The cortisol is fantastic because we are able then to preserve our progesterone. But that same study also showed that it normalized hormones that were precursors to progesterone, such as DHEA A and pregnenolone. And it also normalized testosterone and estradiol as well as progesterone itself. So that I thought was really interesting in men who were under the age of 50. That same study showed that testosterone increased by an average of 49% in just 30 days. So obviously, a larger trial is needed to confirm those supportive hormone supportive effects. But it's really quite, quite interesting. And there are some other interesting studies specifically for women and the reproductive tract, which obviously is intimately linked with our hormones. There was a study that just recently came out showing that spermidine protects the ovaries from reactive oxygen species, and spermidine and spermine. Together, protect it from protects the ovaries from hydrogen peroxide. Which is interesting. And there's an earlier study out of China that one study was from Korea, there's an earlier study out of China, which talks about how spermidine helps with female germline stem cells. What does that mean? Well, these are the cells that you need for egg production for something called gua Genesis. And as we get older, you know, I delayed having children until I was in my late 30s. And then I found it couldn't have them, and ended up giving birth at age 43. For older women looking to get pregnant, it looks like these Polly aims are supportive of fertility. So both in protecting the ovaries and the female germline stem cells and also in normalizing those hormones. Because as mentioned earlier, we need progesterone to really plump up the lining of the uterus in readiness for an egg to implant. And yeah, so those are, those are some examples of how it would help with hormone health. 

Claudia von Boeselager 22:12  
Perfect, and I'd love to have a look at the Canadian study as well. And actually, the Chinese one, and we can link this in the show notes for people looking to dive into it deeper. Also, a repeat guest on the podcast, Dr. Jennifer Garrison, oh, I'm Trina from the Buck Institute looking at ovarian aging and extending or delaying menopause, I should say, because of the detrimental impact on women's health because of it. So you touched on sleep as well. I know sleep is such a big trigger. Are there other benefits with spermidine and sleep for people who might be struggling for sleep that this might be a really impactful supplement to try? Can you talk about that?

Leslie Kenny 22:54  
Sure. So, in addition to the fact that it helps with progesterone helps support hormonal balance, these two precursors, pregnenolone and DHEA, will help with the production of progesterone. We also know that it helps with the clock chain, so spermidine will influence these genes that modulate circadian rhythm. So inside the brain, there's something called the Super cues Matic nuclei or nucleus. And that is what influences circadian rhythm, our sleep-wake cycle, and these clock genes, of which eight of them have been identified; we know that at least two of them are directly impacted by spermidine. We need more studies to see how this affects the other six clock chains. I know that certainly anecdotally, this is probably one this and the hair and nails thing, or these are the three biggest comments we get from our 1000s of customers who say, Oh, I can see on my wearable tracking device my aura bio strap whoop, Fitbit, I can see that my sleep has improved. From the time that I took this product, it was very obvious. Most people will see an increase in deep sleep. Some people will see an increase in both few people will see an increase in rapid eye movement or REM sleep. Deep sleep is very important, especially to women. And the reason why is that it is when the glymphatic system is active. That's when the different compartments of the brain shrink and allow cerebrospinal fluid to flow between those different compartments and take away waste from the brain. And this was discovered by a Danish sign interest at Cornell, you know, it's something that we didn't know she believes that nutrients are also taken into the brain at the same time that we haven't been able to prove that yet. And it's why people like Dr. Dale Bredesen, just like the woman you mentioned at the Buck Institute, have12 said that delaying menopause is beneficial to women. Because of the sleep aspect. If you in middle age do not get enough deep sleep, then the chances of getting Alzheimer's and dementia later in life are much higher. And women, as a matter of fact, have twice the likelihood of getting Alzheimer's or dementia than men. And if you ask Dale Bredesen about this, he'll say, well, look back at what happens in the middle-aged 15 to 20 years prior these women tend to not be getting good sleep, and he is a big advocate of HRT for women, not just for heart health and bone health, but for brain health and specifically with that link back to sleep and deep sleep. So, that is those are some of the ways that it helps with sleep. 

Claudia von Boeselager 26:13  
Yeah, which is so important for the intake of spermidine, right so there are certain foods, and maybe you can discuss that and foods versus supplementation, and then what are some best practices around supplementation that you would recommend? 

Leslie Kenny 26:31  
So I mentioned earlier that you could get the poly Amiens in high quantities and things like mushrooms, but also in Legos, beans, and seeds have them in high quantities peas would be a good example as well. And they are, however, in all plants. They are living plants that you see some, like the legumes, have more, now fermentation will enhance that amount. And that's why Notto in Japan has the highest quantity of these poly Amiens have any other food source bar none. After that, you could then, if you're going down the fermentation route, of course, all these traditional societies that are renowned for longevity, whether it's in the cost in the Caucasus or in Okinawa, they have a fermented food practice. And so in Okinawa, they actually ferment their notto longer than the other Japanese; they ferment it for a year. And yeah, it's quite a different taste to the natto that you get in the rest of Japan. And kefir, kombucha, sauerkraut, kimchi, all of these are opportunities to get more of these poly Amiens into our diet along with the beneficial probiotics and colony forming units that will be there and the prebiotic fibers in the, you know, in the cabbage for the sauerkraut, for instance. Some people, unfortunately, react to high histamine load. So all fermented food, whether it's cheese or sauerkraut, is going to have a lot of histamine. So if you are very highly allergic, then you're going to have to look for other food sources that don't have been fermented. So we're back to our mushrooms and nuts and seeds in terms of supplementation; try to go for a food-derived source of these, not just spermidine but the poly Amiens. And the reason why is that spermidine spermine and putrescine are part of a salvage pathway, a recycling loop. And you don't want to miss the opportunity for your body to use that pathway. I've seen a lot of synthetic spermidine products on the market. And the two problems with that are that you don't then get to access this salvage pathway. But you also won't get this cofactor, poly Amiens brain, which is very good for DNA methylation, you know, turning on and off the genes that are epigenome. But you don't have them; the precursor molecule Putri seems to help you make more of both. But in addition, synthetic spermidine is what we call a two-dimensional molecular mimic. So if I take my hands, and you know I put them facing palms facing each other, we would say, oh yeah, they look exactly the same. Those are identical. But we don't give two left hands to a human. Right. And I would not feel like taking a leather fitted leather glove for my left hand, I would not be able to put it on my right hand. And that is the problem with two-dimensional molecular mimics. And I actually wonder if that is why you have to use such high quantities of this synthetic to actually get the same impact of a perfect three-dimensional mimic that nature has created in food, you get the same impact. We have so many people who've tried synthetics, and then they try, and they say, Wow, I never had this effect with a synthetic. Now I see what people are talking about, you know, with the benefits to sleep and the eyelashes and the hair. So that is the other question is this two-dimensional mimicry? We also don't have any safety or efficacy trials in humans on those two-dimensional molecular mimics, whereas obviously, we humans have co-evolved with plants for millions of years. And so you know, this has been in the food supply, we don't have to worry about the safety issue of that. Yeah. 

Claudia von Boeselager 31:08  
Can you talk about the different types of spermidine supplements that you have, 

Leslie Kenny 31:12  
as a company, we make two we have a gluten-free version, which comes from a and very unusual strain of chlorella from Okinawa. I've been to the year to the pools where they're grown outdoors and the sunshine, a very, very clean area. All the other chlorella in the world is grown in industrial areas, which is not great just because of nearby pollutants. Ours is grown on a sort of remote island. And then, we add to that other anti-inflammatories that also contain autophagy activators. So we have an Okinawan lime peel, which has high amounts of something called no Billiton, that's an autophagy activator. And then we have Okinawan turmeric, and that turmeric contains curcumin, which itself is also an autophagy activator but anti-inflammatory, so that particular product has three anti-inflammatories and three autophagy activators. And then we have Primatene original, which is a wheat germ highly concentrated defatted wheat germ version that has a prebiotic added to it, that's going to feed the bacteria in your gut that can manufacture spermidine with the fiber they like to eat. So that when they're happy, they'll make things for you. Right. They're like a little pharmacy; I think most people forget about this, whenever we put something in our mouth to nourish ourselves, we've got to remember to nourish the mitochondria in our gut, you know, the bacteria that actually make all these wonderful compounds like B vitamins and serotonin for us. So those are the two things that we make. There are obviously a lot of other products on the market. I've touched briefly on synthetic. But I'd also like to just mention that there are liposomal versions of spermidine. And there's also an IV version of spermidine. And you get this question a lot; oh, I've seen liposomal il get into the cell better wanted. And that's only if you believe that these poly Amiens can't actually get into the cell. So Polly aims again, are made from amino acids. If we believed that the only way amino acids could cross into the cell was with a lipid layer around it, then we would all be taking liposomal collagen, but we're not. And that's because the college can get in easily there's no need for that lipid layer. The other problem is when you put a lipid around it, it goes through the digestive system and is not processed in the gut. Now why is it important for it to go through the gut because of the fact that it actually makes the gut makes metabolites that are helpful to the body? And we know that in infants when you know when they get pulling aims in the gut from breast milk. What happens is the immune cells in the gut are activated and that leads to lower allergies in these breastfed children. So that is an example of why you want to have the gut be exposed to the pulling Amiens, but the other reason is that the junctions the tight junctions of the gut; if you have a leaky gut, you want to close them up and spermidine does that it actually tightens up those junctions. And so, I think bypassing the gut is not a great idea because you want those benefits, right? The immune activation, and you want the tightening of the cells of the gut. And IV, of course, also completely ignores the gut. And its role in all of this, which I think is I don't think bypassing the gut is actually a good thing. I think that this is where the magic happens in the gut itself. So that's just a way of explaining, you know, there are so many options out there. But why is food derived? These are the reasons why. 

Claudia von Boeselager 35:37  
Yeah, no, that's pretty clear. Are there any contraindications for taking spermidine supplements? Is there any category of people that it's definitely not for? 

Leslie Kenny 35:46  
Well, if you have advanced cancer, you have to be very careful because poly Amiens, just like glucose, even ketones, some cancers can use poly Amiens in the same way they can ketones and glucose to grow. So you would want to know to speak with your doctor; that said, there was a really fascinating paper by the Nobel Prize winner from 2018. So he was a co-Nobel laureate from Japan, Professor Huncho; coauthored a paper in October of last year on spermidine. And its role in balancing the immune system such that the immune system could better target molecules like cancer cells going rogue like that. And you must always talk to your physician; that would be an interesting paper to reference.

Claudia von Boeselager 36:44  
And we'll link these in the show notes as well. To get them from you separately, Lizzie, of course, let's talk about research. There was a research paper that came out that questioned the impact of spermidine. What is your view on that one? I know some people might have come across them. 

Leslie Kenny 37:01  
Was that one out of the University of Lubeck? Or was it? 

Claudia von Boeselager 37:07  
I have the link here. 

Leslie Kenny 37:08  
There was? Oh, yeah. So so that one, yes. I talked to Dr. Gutta Oscillate, who's one of our scientific advisors here at the University of Oxford, about that very paper. So that paper actually only used university students from Lubbock; I believe the age range was 25 to 35. So they may have had some older grad students. And the problem is that with relatively young people under the age of 40 when you supplement, you're not going to see a spike because their levels are already high. The body does not say, oh, right, I've got plenty of this. And I'm just going to keep stockpiling more and more and more; it will use it for other things, or it will excrete right; this happens with B vitamins. This happens with all the water-soluble vitamins, right? The body will excrete these things. And so this is what we believe is happening; there was a study by Dr. Richard Miller at the University of Michigan, it was an NIH National Institute of aging studies, well in mice, and they had a similar conclusion. But in both cases, whether it was mice or humans, they were using very young, very young people. Now, we know from the research done at Oxford, if you're looking at older people, you can actually see these levels increase. And it's not just even the work at Oxford, it's another at other institutions. In Japan, for instance, if you have an older cohort of people, you can see the levels the blood serum levels of spermidine going up. Now, the Lubeck paper actually talked about how they thought spermidine was being converted into spermidine. spermine, I've mentioned, is important because of the DNA methylation power. So we use that to turn genes on better beneficial to us, and the negative ones off. So screaming definitely has a role to play. But I think again, in these young people, because their spermidine levels were already high, maybe then they thought, right, okay, we will convert some into spermidine. And that's that poly AIMIM salvage pathway that I mentioned, where they can turn into each other. And with so much permitting, maybe they just increased sperm mean and then tried to optimize the epigenetic expression. That's the only thing that that gotten I could think of, you know, what was going on with that paper. You know, what, what did what was actually happening with that cohort of very young people And it's also why I say unless somebody is exhibiting inflammation, active inflammation, like huge amounts of acne or joint pain when they're very young, I don't actually say, or supplement with this product, because you should be capable of manufacturing in your tissues and gut biome. And yes, okay, of course, if you've had exposure to lots of broad-spectrum antibiotics, and you've wiped out those colonies of spermidine and spermine, manufacturing, got bugs, okay, well, then, yes, maybe you should supplement, but the vast majority of young people should not be in those categories. And their level should be fine. And that study also got rid of anybody who was unhealthy. Right? So they would really want to; they would be the ones who would have the faulty product and be in greater need of these polyamines. 

Claudia von Boeselager 41:01  
Thank you for clarifying that as well. What would you say? I mean, the ideal age, if somebody's listening, that's maybe 30. Is it? 35? Were you mentioning inflammation in the body? But where do you see that sort of tipping point of the script, natural spermidine production in the body start to decrease? Are there studies around that?

Leslie Kenny 41:20  
It really depends on your biological age, right? We have a chronological age, which corresponds to the birthday on our driver's license. And then we have a biological age. So if you are aging faster, right, and some people get premature grey hair, these people are possibly internally aging faster. If you have a higher biological age, then maybe you should start taking it. Generally, I would say that it happens mid-40s. Right. I've heard other people say, Oh, it happens earlier. I've not seen definitive studies showing, oh, 25 This definitely happened; you've hit a kind of wall. Whereas by 45, a lot of women have had children. And we women give up lots of our poly Amiens to our babies in our breast milk, and we don't top up that's why women, after they breastfeed, oh, I'm losing all my hair, what's going on? I've delivered a baby, you know, I don't have as much hair as I did before. Well, that's because you've given it all to the baby. When we are babies, we have the highest concentration of these poly aims in our body that we will ever have. And we do take it from our mothers. So around that time would be good mess ups, let's say after pregnancy, and breastfeeding, before menopause, and that perimenopause time, I would say would be good. Men, kind of depends again on how much stress they expose themselves to I have met men who, you know, are under great stress at work. They're Ultra marathoners or they're, you know, they're really pushing their bodies to the limit with Iron Man after Ironman after Ironman. And they say I don't know why my hair and beard have turned white. I'm so fit. Like, well, there is such a thing as too much of a good thing. Right? Yeah, chronic inflammation. Well, maybe you need some anti-inflammatories. And as part of that group of anti-inflammatories, whether it's omega threes or curcumin, you might want to try some spermidine show.

Claudia von Boeselager 43:44  
Let's change gears and talk about the work you're doing with the nonprofit Oxford Longevity Project. Can you share more about your work there and what you're planning? 

Leslie Kenny 43:54  
well, in what we've done in the past, and this was a product of COVID, really. My co-founders are Sir Christopher Ball, Professor of cardiovascular physiology at Oxford, Dennis Noble, and Dr. Paul Chen, who is a doctor at two of the Oxford colleges. We really wanted to bring the science to the lab bench, we wanted those discoveries to be brought to the public sooner. And it generally takes around 18 years to get these discoveries made in the scientific lab to the public. So our format is really having a breakthrough scientist explain what they're learning and put them together with a clinician who's basically translating that science into a protocol for patients. And in the past, we have really focused on this idea of autophagy. It is a big concept in regenerative medicine. If I look back at some of the biggest concepts, I would say the Yamanaka factors that were in 2010 the Nobel Prize As was awarded then you had 2016 for autophagy and 2018 for cancer with Professor Honda. So these big ideas, we want to shine more light on them. And we've looked at we've had Dr. Dale Bredesen speak on Alzheimer's. We've had a Professor Jin Satish Shima from Rutgers University Medical Centre, who's in autophagy. And cardiovascular experts speak together with Professor Robin Chattery, who's one of our highest-ranked principal investigators, but also clinicians at the John Radcliffe Hospital, the teaching hospital of Oxford. So they were paired together we had one specifically on a toffee G fasting and women. That was Professor OB enough divan from Washington University in St. Louis, and Dr. Stephanie Aseema was the translational doctor. She's a Canadian clinician and author of a program called the Betty Body, where she looks at how women can optimize hormones with diet. And now we are about to launch our very first in-person event at the University of Oxford on Saturday, the eighth of July. It's an all-day event with lunch inside the Victorian Gothic Hall of Keeble College. So very Harry Potter; it's going to be Harry Potter meets longevity. And we have some great speakers who are going to present on everything from optimizing hormones for longevity to optimizing hormones for exercise and longevity. And looking at the weight loss drugs, there are GLP one inhibitors like Ozempic we go V. Are they safe? Are they not? Looking at AI, the use of AI, and longevity, looking at what the A-listers in Hollywood are using to stay young as they get older. And then talked to two of our fantastic co-founders, actually three of our co-founders, two are in their 80s, Sir Christopher and Dennis Noble. And then, Dr. Paul Chen will be presenting on using a holistic approach to look at cancer. And how do we look at that if we have already had it and we're recovering, or if it runs in our family, we want to prevent it? So those are, you know, some of the presentations. I'll be the master of ceremonies. Nothing like free cheap labor to help with it. All of your moving everything along. But I think it's going to be a really fun day and an opportunity to meet like-minded people with an interest in aging vibrantly.

Claudia von Boeselager 47:56  
Beautiful, yeah. So thank you for sharing that. Speaking of aging well, if you could live Lesley to 150 years old with excellent health, how would you spend those years? 

Leslie Kenny 48:11  
Oh, I would definitely. I would definitely do lab research in endocrinology, probably immunology. Yeah, those two would be fantastic. I would absolutely go back to school, but I would want to do original research, probably on the thymus for the immune system and thyroid and adrenals, because they're very close to my heart, being a Hashimoto survivor. Wow, there's so much I could do. Right. Should I learn to surf? I think I think I would really like to take up ice skating again. Yeah. 

Claudia von Boeselager 48:50  
I love it. I know; kite surfing is on my list. I've had two failed attempts that will not fit. Once, I broke my small toe randomly. So in a bit on Zanzibar, I decided not to go to the hospital to get that looked at. But that's beautiful. 

Leslie Kenny 49:08  
It's a good story. It's a wonderful cocktail party story. 

Claudia von Boeselager 49:11  
Exactly. I have a few of those over the years of traveling. Let's see what trends and developments in the longevity space, in general, you find most exciting. 

Leslie Kenny 49:22  
Wow, so much is happening. I do think AI is very exciting just to be able to draw all of these strands of data together. I think it's overwhelming for patients to the blood test, we get the gut biome test, you know, the cortisol test, all of these things, who is actually looking at all of this and saying, oh, right, now that I overlaid the gut biome test on your blood test results, I understand what's going on. I don't see doctors able to easily do that. We are Actually co-sponsoring this with a Swiss company called Biopolitical. And they have some software that does that. And it's meant for practitioners, and I can definitely see that being a trend. But the other trend I see is that patients after COVID, we all understand that we have a lot of responsibility with a big role to play here. And I think that that message of, well, I might not be able to solve the whole problem. But if I can make my body comparatively better, comparatively healthier, I have a statistically higher chance of fighting off these pathogens like COVID that might strike, and we might not have a solution for right. So I see patient responsibility increasing; I think that means that there are great opportunities, helping people on the lifestyle front, optimizing movements, and sleep diet; I also see more people, especially in Britain, beginning to get the message around, not just supplementing orally, but mentally now, what I mean by that is, the thoughts that we feed our brain are as important as the food we put in our mouth. Because if we are thinking toxically or we are exposed to a toxic environment, that's a terrible diet to live on; it's hard to thrive. Right? When you have that, that kind of, let's call it a mental diet. And so I see more people becoming aware of mental health as an issue, and we actually have the director of aging research at King's College; he's going to be in conversation with Dennis Noble around mental health, aging, and longevity because that's, that's a big missing component. And in all these, these zones of longevity, we see it's not just those physiological levers that people move, but it's social. Yeah. Right. 

Claudia von Boeselager 52:10  
So if you look at Harvard's longest-running or the world's longest-running study from 1938, right, on happiness and longevity, right, in older years, they show the connection. Relationships were the key components of happiness for longer. 

Leslie Kenny 52:26  
Yeah, yeah, it is. It's so so underestimated. So, so yes, you know, you could look at exosome treatments and PRP in your knees or your scalp or, you know, whatever. Yes, there are all sorts of interesting science things. But I do think that there's a lot of low-hanging fruit out there. And consumers patients are now really getting that they can access those 

Claudia von Boeselager 52:55  
exciting times. Lizzie, for my listeners interested in understanding spermidine and longevity better, what online resources or books would you recommend they start with? 

Leslie Kenny 53:06  
There's actually a pretty good website called And you'll find a lot of studies there on this, and they're sort of paraphrased. And in terms of the pulling Amiens, That's tricky. There really isn't a sort of one-stop-shop book on this. And maybe I should write. Yeah. Next project. Yeah, at what time? But yes, there isn't really a one-stop shop to find out more about that. But start with about And we have a few things on the Oxford website. For those followers who are on Instagram or LinkedIn, I often post information at Oxford Healthspan is the handle on Instagram. I'm Leslie Kenny on LinkedIn. And you can follow some of the I'll post studies not just on the polyamines; I'll do it on the gut biome on aging just generally. And so you'd be able to find some information there too. 

Claudia von Boeselager 54:19  
Excellent. And we'll link those in the show notes. Great. Do you have any final ask or recommendation or any parting thoughts or message for my audience today, Lesley, 

Leslie Kenny 54:29  
you're never too old to make a difference. Starting today, even the smallest action can have the biggest effects. And there's a great quote from the Dalai Lama who says if you think you're too small to make a difference, remember what it's like to sleep with a mosquito in the room. 

Claudia von Boeselager 54:50  
I love that quote.

Leslie, thank you so much for coming back on the podcast. It was so wonderful to have you on Oh

Leslie Kenny 55:00  
Likewise, thank you so much, Claudia.

I’m Claudia von Boeselager

Longevity Coach, detail-loving educator, big-thinking entrepreneur, podcaster, mama, passionate adventurer, and health optimization activist here to help people transform their lives, and reach their highest potential! All rolled into one.

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