Muscle for Life with Mike Matthews - Can Conjugated Linoleic Acid (CLA) Help You Get Bigger, Leaner, and Stronger?
Episode Date: February 27, 2023Looking for a dietary supplement that can help you lose fat, build muscle, and improve your overall health? Many people claim CLA (conjugated linoleic acid) is the answer. CLA is a widely popular supp...lement in fitness circles and advocates believe it provides numerous health benefits. From promoting muscle growth to aiding fat loss, and even reducing the risk of metabolic and cardiovascular disorders, CLA seems like a wonder supplement. Is it too good to be true? In this episode, we'll explore the evidence surrounding the benefits and risks of CLA. Is it really free of side effects? Is there enough reliable evidence to back the proponents’ claims? Listen to this podcast to find out! Timestamps: (0:00) - Please leave a review of the show wherever you listen to podcasts and make sure to subscribe! (1:54) - What is conjugated linoleic acid? (11:13) - Try Whey+ risk-free today! Go to buylegion.com/whey and use coupon code MUSCLE to save 20% or get double reward points! (13:49) - Does CLA benefit muscle building? (16:29) - What are the effects of CLA on insulin sensitivity? (18:45) - Can CLA boost performance? (20:09) - What are the effects of CLA on cardiovascular health? Mentioned on the Show: Try Whey+ risk-free today! Go to buylegion.com/whey and use coupon code MUSCLE to save 20% or get double reward points!
Transcript
Discussion (0)
Hello, hello, and welcome to another episode of Muscle for Life. I am your host, Mike Matthews.
Thank you for joining me today. And I know I sound a little bit funny because I am still a
little bit congested from a cold that I had for a few days. So I hope it is not too annoying. I
was putting off recording this episode for a couple of days waiting for my normal voice to return and figured this is probably
good enough. So here we are to learn about a popular body composition supplement that has
been popular for some time. When I got into working out when I was like 17 years old, So this is like 20, 21 years ago, CLA was popular. So for 21 years now,
it has remained a best selling body composition supplement. It is supposed to improve body
composition in a couple of ways. It is supposed to aid fat loss, it is supposed to aid muscle
building, it is also supposed to decrease your risk of poor metabolic and cardiovascular health.
It is supposed to increase testosterone production and workout performance and all of that without any adverse side effects.
And hence its popularity.
However, many people are leery of claims like those.
And many of those people reach out to me and ask my opinion on CLA.
And they also often notice that my sports nutrition company Legion does not sell CLA. Is that because
we don't endorse it? Or we just haven't gotten around to selling it? And so in this episode, I'm going to give you a balanced,
evidence-based take on CLA, what it likely can and can't do, and why I don't currently sell it.
Okay, as usual, let's start this discussion with a quick description of CLA. What is this stuff?
Well, the acronym stands for conjugated linoleic acid, and that is just a group of naturally
occurring fatty acids.
CLA is found primarily in the meat and dairy of different animals like cows, goats, sheep,
and buffalo, though the amount can vary depending on the animal's diet, altitude, breed, and
lactation age. For example, some evidence shows that dairy produced by cows that are free pasture roaming cows out eating grass like cows were meant to do
can contain up to 500% more CLA than cows that are fed a typical dairy cow diet of corn and corn silage, grass silage, and other byproducts of human food production,
stuff that isn't otherwise useful, like almond husks, for example. Now, CLA can also be created
in a lab. Scientists can synthesize it using vegetable oils like sunflower oil and safflower
oil. And there are many different forms of CLA as well. There are actually 28
possible forms. And all of these forms share the same chemical formula, but the atoms are arranged
differently in each different form. And that means that they have slightly different properties.
Now, the forms that you will find in supplements are usually C9, T11, and that's also the form that is most prevalent
in the human diet. Research shows that 75 to 80% of CLA in the human diet is this C9, T11 form,
as well as another form called trans-10, cis-12 CLA, or T10, C12. And in fitness circles,
these CLA supplements are popular specifically for weight loss, for fat burning,
also for muscle building, but a lot of the marketing claims revolve specifically around
weight loss. So let's talk a little bit about that. While scientists don't fully understand
how CLA affects fat burning, some believe that it's connected to how CLA interacts with what are
called paroxysome proliferator activated receptors. That's a mouthful, usually referred to just as
PPAR. That's the acronym commonly used. And what those receptors are, are transcription factors,
which are proteins that bind to specific DNA sequences and then
regulate the expression of genes. And in the case of these paroxysome proliferator activated
receptors, the genes that are affected include ones related to metabolism. So CLA can influence
metabolism at a cellular level. And research conducted in rats shows that CLA can influence metabolism at a cellular level.
And research conducted in rats shows that CLA,
and particularly the C9, T11, and T10, C12 forms
that you'll find in supplements,
binds to the PPAR-A receptor,
which according to some researchers can increase fat burning.
Now, there's also evidence from a human study
that T10C12
inhibits PPARY, which is a receptor found in fat cells that increases fat gain. That said,
other research on human cells shows that C9T11 activates PPARY, so having the opposite effect.
And if we look at some other research on human cells,
we see that there's evidence that CLA can suppress
or inhibit enzymes that can contribute to fat gain.
We also can see in some other animal studies
that it appears to increase levels of enzymes
that boost energy expenditure.
And so you see why there has been a lot of interest
in CLA over the years.
There is a fair amount of preliminary research that shows that it may be an effective fat loss supplement. It may be worth adding to your regimen. It is a natural supplement, so it is not going to produce anything like the results you would see from a proper calorie deficit, of course.
course, you know, if you know what you're doing and you have a fair amount of fat to lose, you could lose one, two, maybe even three pounds of fat per week if you have a lot of fat to lose.
Would a natural supplement ever be able to match that? No, of course not. But if you could add a
natural supplement and let's say you could lose an extra pound of fat per month, that's not bad,
right? And if you could maybe take two supplements like that or three,
and maybe their efficacy when used together doesn't exactly add up, so you can't lose an
additional three pounds of fat per month, but maybe it's an additional two pounds of fat per month.
And if those supplements are relatively inexpensive and are proven to be safe,
that is worth considering, right? There are many people
who would go in for that because they do the math and they see that that could shave a month off of
their cut, for example, if they have a fair amount of fat to lose. And so such is the promise of CLA,
that it can make enough of a difference to be worth the money and worth the hassle of swallowing
pills every day. Now, if you are scientifically savvy,
you know that the preliminary research that I've shared with you, the research on human cells,
not in living human beings, and the research in rats can be promising. It can suggest that
further research should be done in living humans, but the results that are seen in rats and in
in vitro research cannot be directly extrapolated to in vivo in living people. You have to do that
research separately because many times things don't exactly pan out. For example, although we share a lot of DNA with rats, our metabolisms work in very
different ways. And so you can find quite a few examples of supplements and drugs that have
promising effects in rats, promising metabolic effects specifically related to weight loss and
energy expenditure that then don't work in humans because our
metabolisms are different in very meaningful ways. One of them being that rats have a much
faster metabolism than us humans. So when we look at these weight loss studies and we see
time and time again that in mice, CLA works. It significantly boosts fat burning. It decreases
appetite. It prevents fat storage. It's great.
What about human studies, though? Well, unfortunately, most of the studies done in
living people with CLA have shown no effects on fat loss whatsoever. And if we look at the few
studies that have shown positive effects, the results are underwhelming. For example,
in one study published in the journal
Nutrients, people who supplemented with CLA twice per day for 12 weeks, so 12 weeks, lost about
one and a half pounds of fat. In another study by scientists at the University of Barcelona,
overweight people who took CLA for 12 weeks lost about 1.3 pounds of fat. And perhaps the most dramatic weight loss seen in a CLA study
comes from research conducted by scientists at the Max Rubner Institute. And in this study,
researchers found that 85 obese men and about 75% of them had metabolic syndrome who took CLA for
four weeks lost about two and a half pounds of fat. Now, again, those are a few
studies that have shown positive results. Most of the studies have shown no such results. And further
muddying the matter is research that shows that CLA's weight loss effects can be very unpredictable.
In one study that was published in the American Journal of Clinical Nutrition, some people who took CLA for six months lost about seven pounds of fat, while others gained
over four pounds of fat on average. Research also shows that CLA is not effective, in humans at
least, at preventing weight regain after dieting, and it also does not appear to help people eat less. Whereas again, in mice,
it does reliably decrease appetite. In humans, not so much. So if we look at the data on the whole,
if we look at the weight of the evidence, it's that CLA is a dud. When you look at most of the
studies, you have no meaningful effects on fat loss. And if you look at the studies that have shown positive effects, they also have shown unreliability,
inconsistency, and irrelevance, just inconsequential amounts of additional fat loss.
If we look at them in terms of your average gym goer who is looking to lose anywhere from 5 to 15 pounds and then who is
looking to diet for anywhere from probably 4 to maybe 16 weeks. If you add CLA to that and if you
are generous in your expectations, it is just not going to make that much of a difference in a best case
scenario. So I think there's little reason to add CLA to your fat loss supplement stack, so to speak.
One of the easiest ways to increase muscle and strength gain is to eat enough protein and to
eat enough high quality protein. Now you can do that with food. Of course, you can get all of the protein you need from food, but many people supplement with whey protein because it is convenient and
it's tasty and that makes it easier to just eat enough protein. And it's also rich in essential
amino acids, which are crucial for muscle building and it's digested well, it's absorbed well. And that's why I created Whey Plus, which is a 100%
natural grass-fed whey isolate protein powder made with milk from small sustainable dairy farms in
Ireland. Now, why whey isolate? Well, that is the highest quality whey protein you can buy,
and that's why every serving of Whey Plus contains 22 grams of protein with little or no
carbs and fat. Whey Plus is also lactose-free, so that means no indigestion, no stomach aches,
no gassiness. And it's also 100% naturally sweetened and flavored, and it contains no
artificial food dyes or other chemical junk. And why Irish dairies? Well, research shows that they produce
some of the healthiest, cleanest milk in the world. And we work with farms that are certified
by Ireland's Sustainable Dairy Assurance Scheme, SDSAS, which ensures that the farmers adhere to
best practices in animal welfare, sustainability, product quality, traceability, and soil and grass management.
And all that is why I have sold over 500,000 bottles of Whey Plus and why it has over 6,000
four and five star reviews on Amazon and on my website. So if you want a mouthwatering,
high protein, low calorie whey protein powder that helps you reach your
fitness goals faster, you want to try Whey Plus today. Go to buylegion.com slash whey. Use the
coupon code muscle at checkout and you will save 20% on your first order. And if it is not your
first order, you will get double reward points. And that is 6% cash back. And if you don't absolutely love
WayPlus, just let us know and we will give you a full refund on the spot. No form, no return is
even necessary. You really can't lose. So go to buylegion.com slash way now, use the coupon code
muscle at checkout to save 20% or get double reward points. And then try WayPlus risk-free and
see what you think. Now, what about muscle building? That is also often used to sell CLA.
It's often sold as a body recomposition supplement. But most research shows that is simply not the
case. And the few studies that indicate it may be able to help,
and these are the outliers, these are the exceptions, not the rule, they also show
inconsistency. So for example, scientists at Rawat Research Institute found that young obese men who
took CLA and fish oil for 12 weeks increased their muscle mass by about 2.4%, though young lean men and older obese and lean men saw
no benefit. That's odd. Another study was conducted by researchers at the University of North Carolina,
and it found that obese people who took 6.4 grams of CLA, which is a lot, every day for 12 weeks,
gained about 1.3 pounds of muscle in that time frame. But then you have people who took
3.2 grams of CLA, which is still a decent amount. Well, they took it every day. They saw no benefit.
One more example is a study that found that overweight people who took CLA for a year
increased their muscle mass by an average of about 2%. But when you look at the data and you
look at the individual results, you see
inconsistency. You see that some people lost as much as two and a half percent of their muscle
mass over the course of that year. And so the evidence is clear. CLA is not going to help you
gain muscle faster. It is also not going to boost your testosterone levels. Some people make that claim as well because there's research
on human cells that found that CLA may be able to increase your testosterone or increase testosterone
production, but the results were not replicated when the scientists repeated the research in
living humans. There's also a study that is often used to sell CLA as a testosterone booster,
where scientists injected mice with a mushroom extract containing high amounts of C9T11,
and that showed that it could prevent the enzyme aromatase from converting testosterone to
estrogen. Okay, interesting. But again, this is a study in mice, not humans, and we can't just
directly extrapolate rodent research to humans. And also the mushroom extract used contained
other compounds that could have been responsible for the result. So it's impossible to say whether
the CLA, whether the C9, T11 form of CLA contributed or not. It's also, of course, impossible to know
whether we would see similar effects in humans without doing that research. Improving insulin
sensitivity is another common claim used to sell CLA, and insulin sensitivity refers to that, just
how sensitive your body is to the effects of insulin. And generally speaking, higher sensitivity
is better. That means your body doesn't need to produce as much insulin.
You will be able to deal with carbohydrates better.
And of course, your risk of type 2 diabetes then is much lower.
And generally speaking, your metabolic health is higher, is better when you have a body
that is more sensitive to the effects of insulin rather than less sensitive. And there are
animal studies that show that the C9-T11 form can increase insulin sensitivity. Okay, interesting.
But then there's research that shows the T10-C12 form causes inflammation that prevents glucose
and fatty acids from entering cells. And so that is increasing insulin resistance. Not good. But of course, now we have to look at human studies and we see inconsistency. That is a theme in the CLA research. For example, in one study, there were 10 men who took 3.2 grams of CLA every day.
experienced an increase in insulin sensitivity. Two of them experienced a decrease, so an increase in insulin resistance. That's bad. And then the remaining two experienced no change. And then
there was another study that was published in Applied Physiology, Nutrition, and Metabolism.
And in this experiment, researchers found that out of nine people who took CLA every day,
out of nine people who took CLA every day, three experienced an increase in insulin sensitivity by about 9 to 13 percent, but six decreased insulin sensitivity by 9 to 79 percent. And then we have
more human studies that have shown that CLA has little effect or no effect on insulin sensitivity.
So the problem here is when you take CLA to increase your insulin
sensitivity, it may work slightly. It may do nothing, meaning you're just wasting your money.
And then it may have the opposite effect and it may have a strong opposite effect, which would be
bad. And so I don't recommend taking CLA for improving insulin sensitivity.
Now, what about athletic performance?
Can CLA boost your endurance?
Can it boost your power?
Can it boost your strength?
Maybe, maybe not.
It's more of the same because some studies show that it has no effect whatsoever on these
parameters.
There are a couple of studies that show that it may slightly increase athletic performance.
And as expected, there are
some anomalous results in the literature. For example, one study showed that CLA increased
the bench press strength, but not the leg press strength in men and didn't have any such effects
in women. So the evidence here is inconsistent. There's not much to go off of. We can't really draw any
firm conclusions about whether CLA can improve athletic performance. At least there's no research
showing that it can decrease athletic performance. So I wouldn't personally spend my money on it.
If I were looking to improve my workouts, for example, I would go to ingredients like beta alanine and citrulline and caffeine and
theanine and nitrates. I would go to things that have a large body of evidence showing efficacy
in healthy humans. I wouldn't waste my money on CLA because it may or may not do anything.
And it looks like currently the best case scenario is
it has a slightly positive effect. Now, the last topic I want to comment on is CLA and cardiovascular
health, because many older people in particular are marketed to with claims regarding cardiovascular
health. Many older people are told that they can take CLA
to have a healthier heart. And of course, if they have a healthier heart, chances are they are going
to live a longer and healthier life. So what does science have to say? Well, you probably can guess.
The results are all over the place. There are some animal studies that show that CLA may protect
against cardiovascular disease by boosting arterial
health, improving cholesterol levels, and reducing oxidative stress. But on the other hand,
if we look at human studies and cholesterol levels, for example, we have conflicting results.
We have some studies showing that CLA can indeed improve cholesterol. And then we have others
showing that it has no effects. It doesn't alter cholesterol levels at cholesterol. And then we have others showing that it has no effects. It
doesn't alter cholesterol levels at all. And then there are others suggesting that it may have a
detrimental effect on cholesterol. Furthermore, research shows that CLA may actually increase
oxidative stress in the body and levels of blood markers such as C-reactive protein. And both of those things, higher levels
of oxidative stress and higher levels of C-reactive protein are associated with a higher
risk of cardiovascular disease, not a lower risk. But then, despite that, there's research that
shows that taking CLA doesn't actually appear to increase your chance of developing cardiovascular disease.
So as you can see, CLA is just a strange molecule, and I would not recommend taking it for the
purposes of improving heart health because it may be able to reduce the risk of cardiovascular
disease. It may not. It may actually increase the risk of cardiovascular disease, despite one study showing that it
appears to not.
But I did mention that there are a couple of mechanisms that have been observed that
are associated with an increase in the risk of cardiovascular disease.
And so instead, if somebody were asking me, hey, are there a couple of supplements I can
take for a healthier heart?
were asking me, hey, are there a couple of supplements I can take for a healthier heart?
I would say, yeah, take a well-formulated multivitamin, for example, that is going to ensure you don't have any major nutritional holes in your diet with essential vitamins and minerals.
And I would recommend looking into CoQ10, which is often in a well-formulated multivitamin like my own, which is called
Triumph. You can find it over at buylegion.com, B-U-Y legion.com slash Triumph. I would also
recommend eating enough fiber. So eat your fruit, eat your vegetables. I would not necessarily
recommend supplementing with fiber. Get it from food. There's a difference. Omega-3 fatty acids,
take a fish oil. That is probably going to decrease your risk of heart food. There's a difference. Omega-3 fatty acids, take a fish oil. That is probably
going to decrease your risk of heart disease. There's good research that indicates that.
And so that is the score with CLA. That's why I don't take it. And that's why Legion does not
sell it, even though many people come to us asking for it. Why don't you have CLA? I want to buy CLA.
I like you. I want to support you, not whoever else.
Well, I've explained now why I don't sell it. It's like BCAAs. Legion gets asked all the time
to make BCAAs. And our customer experience team has a nice little canned response that explains
why we don't sell BCAAs, which basically comes down to the weight of the
scientific evidence is that they don't do anything for anybody who eats enough protein.
And funny enough, many people appreciate the honesty, but then just say, hey, well,
you know, it makes my water tasty. So if you do happen to make BCAAs, even if it's only just to
make tasty water, I'll buy them from you.
And I appreciate that. But unfortunately, that's not a great sales pitch, right?
You can imagine the sales page, which is explaining the research that shows that you don't need to
take amino acid supplements if you eat enough protein. And if you don't eat enough protein,
you should just eat enough protein. Don't take amino acid supplements.
They are a waste of money.
And if you eat enough protein and take a bunch of amino acid supplements, there are some potential negative side effects.
But if you really want to give us your money, if you really want some tasty water and you're
not willing to just like put some fruit in your water or some flavored drops, okay, fine, here are BCAAs.
I'm no marketing master, but I'm good enough to know that that is not a great strategy. And so
anyway, I wish it were otherwise with CLA and BCAAs and EAAs and quote unquote testosterone
boosters and many other supplements that many people buy, but which just don't have good scientific evidence
for efficacy. If I could sell such things ethically, I would, because then Legion would
make more money and I would make more money and that's good for Legion and that's good for me.
But I'm not willing to lie to take people's money. So I don't sell them.
Well, I hope you liked this episode. So I don't sell them. it a little bit more easily found by other people who may like it just as much as you.
And if you didn't like something about this episode or about the show in general, or if you have ideas or suggestions or just feedback to share, shoot me an email, mike at muscleforlife.com,
muscleforlife.com, and let me know what I could do better or just what your thoughts are about
maybe what you'd like to see me do in the future.
I read everything myself.
I'm always looking for new ideas and constructive feedback.
So thanks again for listening to this episode.
And I hope to hear from you soon.