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Karan Rajan

Karan Rajan

Doctor

Sep 28, 2026

14:42
Or did you study it? Like, talk to me about how you got started with content.
14:44
Yeah, it's interesting.
14:45
Like when I first got into content, it was just, you know, so if you rewind a little bit, I started content before, you know, content was really a thing.
14:56
Back when it was a weird thing to make videos and put them online, I was doing it.
15:00
And now it's weird if you don't make videos, right? So 2010 is when I started my YouTube journey and just being on screen and, you know, my content style has completely changed since then, you know, the, like those 10 years, but essentially it always starts at the same thing.
15:14
Any new platform or whatever you do is just.
15:17
Throwing things out the wall, seeing what sticks, what works for me for that platform.
19:30
Mm-hmm.
14:07
I'm going to tell you something amazing about
14:09
Throne that a lot of people need to understand more about.
14:12
It has got amazing infrared system that can detect still images of the poop, tell you about the Bristol stool scale of your poop, your size, shape, color, consistency, your toilet time, if you're straining, the evacuation time.
14:27
It can also listen... to the tinkle of your pee and estimate the rate of your pee, your hydration levels based on the Euroflow, the sonography of that as well.
14:41
And it tells you about your prostate health, your hydration levels and your poop.
14:47
Because ultimately what people don't know is that your day-to-day poops, sure, that's important.
14:52
But what is important is perturbations from your baseline.

10 MINS LATER

25:12
This is
12:15
So were Did that inspiration come from to create that?
12:22
Yeah, it came actually from my own medical problems that I had in 2018.
12:26
I did a random blood test and I found out I had high LDL cholesterol, which is the bad cholesterol.
12:32
And several months later, I also had an ultrasound scan, which suggested that because of my high cholesterol, likely I had mild fatty liver disease.
12:39
So as a young man in his late 20s, I was very concerned.
12:44
And I worked with a dietician to kind of get to the cause of some of this stuff.
12:48
And it turned out that I was eating a lot of protein from red meat.

9 MINS LATER

21:27
What's the conversation people on this journey should be having that they're not?
IsabellaHOST
22:33
How much do you know about women's hormones, and do you have any advice to women about hormone replacement therapy?
22:42
Yeah, I mean, I, I would caveat this by saying I'm not obviously like, um, you know, a women's health expert or a hormone expert, but you know, hormones is a pretty wide-reaching category, and we know that they have significant impacts in so many organ systems, you know.
22:56
And you mentioned a couple of life stages there, specifically looking at, you know, menopause, perimenopause, pregnancy, breastfeeding.
23:03
When hormones shift, they have significant impacts on your metabolic health.
23:09
And when I say metabolic health, I mean your changing hormones don't just impact how you feel, for example, things like brain fog or low energy, but it can actually impact body systems which you may not suspect, like your cardiovascular system.
23:24
For example, in perimenopause, rates of cardiovascular disease risk go up because the fluctuating and then eventual drop-off in estrogen, which is cardioprotective and protects the heart, can actually make someone more susceptible to high cholesterol, insulin resistance, cardiovascular disease.
23:41
Changing hormones can actually affect the guts.

10 MINS LATER

IsabellaHOST
33:42
So what, what's the best way of taking, of supplementing ourselves? Is it through powders, liquids, gel, pills? Like, you know, I've heard people say, "Oh, if you're taking a number of different supplements and they're all a different kind of gel-coated liquid, that's not actually very good for your gut." Is it better to take it in a sort of pipette liquid that goes into your water? What's your advice?
15:58
but they don't actually know.
15:59
Yeah.
16:00
So, uh, if we go on the spectrum of the biotics, you've got prebiotics, which is the basic fertilizer for life in your colon, so it nourishes your soil.
16:10
If you think of your garden as your gut, your gut is a garden, there's two ways via which you could have a nice-looking garden.
16:18
You could either just keep buying more plants and flowers and plant them there.
16:22
That would be the probiotics, like adding probiotic supplements, and that's not really sustainable, and it's quite expensive to keep doing that.
16:28
Or you could do a more sustainable and cheaper way, and that's more eco-friendly, which is nourish the soil that's already there and fertilize that soil with the prebiotics.

36 MINS LATER

52:24
Yeah.
8:56
Mm-hmm
8:57
... and then it's dissolved into bile, which is then released into the colon, and then that is excreted.
9:03
Some of the estrogen, it is reabsorbed by the colon and goes back into systemic circulation via the portal vein, and it's recirculated.
9:13
We don't sometimes want all of that estrogen to be reabsorbed back into systemic circulation, because then you can have a s- higher amount of estrogen in the bloodstream.
9:21
The role of fiber, especially soluble fiber, that can increase GI speed, so the sort of, it reduces GI transit time, so more of that can be shoved away.
9:32
So if you've got a shorter GI transit time, there's less time for that estrogen to be reabsorbed in the colon lining.

44 MINS LATER

53:53
Mm.
53:54
Or they were just formulated by some random hack who'd either done a ChatGPT formulation or some manufacturer's just-... churn something together, copycat things, right? And I started buying different fibers that I was using that had high quality, and it was like almost doing, like, a kitchen experiment, like dosing and weighing out in a scale different fibers, and then mixing it in a powder, blending it, and I had the thing.
38:36
Yeah.
38:36
People talk about soluble versus insoluble fiber.
38:39
That is a very old, outdated concept.
38:42
It's not just soluble, insoluble.
38:44
It's about the fermentation propyle- uh, the fermentation profile, the viscosity, um, where it actually ferments in the colon, the actual geographical anatomical location.
38:55
I like to think about fibers as, uh, you know, still simple, but it's a better way of thinking about it, as fast-fermenting, medium-fermenting, and slow-fermenting fibers.
39:05
An example would be, like, apples contain fibers which ferment in the first part of the colon, so here, the ascending colon.

15 MINS LATER

54:19
Is there anything else about the gut microbiome that I'm missing that is really important to you?
5:14
And if somebody is struggling to lose weight or feel satiated when they're just focusing on these plant-based proteins and not protein maxing, what would you say to them?
5:24
We have recent evidence to suggest that plant proteins are not inferior to animal proteins for muscle synthesis.
5:32
Most people who are trying to live a healthy life will diversify their plant protein sources so they'll get plenty of all the amino acids and they get plenty of stimulus for muscle protein synthesis, and that's not a problem at all.
5:46
And protein is satiating, it's one of the most satiating macronutrients you can get, and fiber is as well.
5:51
The problem is in animal proteins, you don't get fiber, but with plant proteins, you get fiber and protein and other antioxidants.
5:56
So that in a package, you know, is arguably as good, if not better.
6:02
I am not a vegan.

5 MINS LATER

11:08
Or is just diversity the name of the game?
25:29
Was any of the science she was sharing that, was it partially true? Was it completely untrue?
25:34
I'm a pretty open-minded person.
25:35
And until I see consistent randomized controlled trial evidence for colostrum having mechanistic effects and also... real world clinical outcomes in a large data set, as we do see with fiber over decades.
25:49
You know, this is the sort of like path that I will take based on the science that we have right now.
25:53
It's not a personal opinion.
25:54
It's just objectively based on the data set we have.
25:58
The problem is there are some very small data sets on colostrum.

11 MINS LATER

36:33
Talk to me a little bit about that.
12:34
But it seems like our generation, I think we're a similar age, and a little bit younger especially, are, like, experiencing these at really high levels.
12:41
Yeah, I think there are, you can say, microbiome disruptors, and I think the number one thing would be now more than ever, there is a pretty wide...Deficiency in fiber that we consume in our diets compared to our ancestors.
12:55
You know, if you look at some populations around the world that are consuming over 100 grams of fiber a day, certain tribal populations in Africa like the Hadza tribe.
13:03
But we're consuming on average, you know, in the US and the UK and Europe, 15 grams of fiber or less is the average, right? And that is very detrimental to the microbiome because it's causing a slow but steady extinction of the microbiome.
13:17
We are seeing a loss of biodiversity, and that is to our detriment.
13:21
The other thing would be there's rising pollution levels.
13:23
Now we know that via the gut-lung axis, the lung exposure and environmental exposure to various toxins and pollutants can have an impact on the lung, which can have an impact on the microbiome.

31 MINS LATER

45:04
... and, you know, hopefully you would feel better," what would that be?
6:58
Let's talk about the gut and then let's talk about why fiber is so important.
7:01
Yeah, so I like to think of your gut as a garden, right? And if you want to maintain that garden and make it look pretty, there's multiple routes you can go down.
7:12
You can just keep buying more plants, i.e. probiotics, and just throwing them in there.
7:17
But a more sustainable and better option is to nourish the soil of that garden, the lining of the colon, and the seeds of life which are already in your garden, your natural microbes.
7:28
And you nourish them with fiber.
7:30
You nourish the soil and you kind of fertilize the soil.
7:34
And that is the role of prebiotic fiber.

28 MINS LATER

35:39
What else is another component that we're doing every day to mess up our gut?
12:35
Is it a, is it a dragon fruit? Is it a pomegranate? What is that?
12:39
All of those- I mean, they don't get those kind of foods in that region.
12:42
They're eating, like, the sort of roots and tubers, like cassava, beans, wheat, corn, things like that.
12:49
And the reason those kind of fibers are really important, and it's come out of a lot of our modern diets, is because they ferment really slowly.
12:58
If you think of your colon, right, you have your colon, which goes up here, that's the first part of the colon, and then the second part goes across, the transverse colon, third part goes down, the descending colon.
13:08
The foods we eat, which are fiber-rich in the modern diet, right, like apples, that's a fast-fermenting type of fiber, and that ferments here, but it doesn't make it all the way here.
13:20
The bacteria which live here are the most beneficial bacteria, and the m- the greatest number of bacteria live here.

35 MINS LATER

48:33
Get it while it's hot at shopskinnyconfidential.com. That's shopskinnyconfidential.com. [upbeat music] Out of all the content that you have done, with eleven million followers across, has been the most viral, and why?
13:25
I'm curious if you're seeing similar prevalence and incidence in the UK and what do you attribute this to? What are some of your kind of prevailing thoughts on why we're seeing an increase in colorectal cancer?
13:38
Yeah, I think it's increasing prevalence worldwide, particularly in Western countries.
13:43
And I think there's probably a twofold reason or there's a myriad of reasons why this is happening.
13:50
Some are grounded in truth, some more hypothesis driven.
13:54
I would say we are more health conscious as a society, more people are getting checked up.
14:00
So with more checkups and improved diagnoses.
14:04
So, you know, the sensitivity and specificity of stool tests and colonoscopies are improving.

18 MINS LATER

32:39
Do you feel that our kind of modern day lifestyle is priming us for dealing with more gut related symptomatology, not just in middle life, but throughout our lifetime vis-a-vis our modern day lifestyles?
13:39
I asked him what the macronutrient does for our bodies.
13:42
I believe that either directly or indirectly, fibre has a role in almost every physiological function in humans.
13:50
But in broad strokes, you could say that there's a dual function.
13:54
One function is...
13:56
it has this laxative type effect where it sweeps through the intestines and it can basically scrape the lining of the intestines and act as a broom to just keep things moving.
14:08
That's the sort of physical mechanical property that fiber fibers usually have.
14:13
And then the other role is more of a chemical role where the fiber and specific types of fibers are digested in different ways by our gut bacteria to then produce different anti-inflammatory compounds, which are then used to nourish the body in many ways, whether it's brain health or gut health or metabolic health.
14:34
If someone isn't getting enough fibre, what does that do to them?
2:20
When you're thinking about advising people about what they can do to make their guts happy, what do you say? And maybe we should start with food, but then I'd love to discuss some of the other things that you talk about as well.
2:31
Yeah.
2:31
Uh, I think it, it does start with food.
2:33
A lot of the at least easy options that someone can make a change from right now, listening to this podcast, from tomorrow, from today even, making that change.
2:41
And we know the gut microbiome is quite adaptable, it bounces back, you know, relatively well, and it's very responsive to change.
2:48
So even within 24 hours of eating a certain food, you can begin to see some changes in the microbiome.
2:54
So, you know, if you look at most of the, you know, literature that's out there, the meta-analyses and the systematic reviews, when it comes to eating for better gut health, it's nothing very complicated if you break it down into, you know, we talk about fiber and prebiotics.
6:38
And I wanna come back to that, you know, the question right at the very beginning, what are your thoughts on probiotic supplements?

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