Back when I was a Ph.D. student, I had this roommate who was a
great athlete; he even went on to play professional sports. He was
also a great student, graduating with honors. And on top of that he
was a great looking guy, a big hit with the ladies.
But despite all the great things he had going for him, he had
one fatal shortcoming: his skin. Whenever he was stressed out about
sport, school, or women, he’d suffer severe breakouts.
Quickly, almost overnight, his face would swell and get overtaken
by bumps, lumps, whiteheads, and blackheads.
And it was then that he’d disappear from existence. He
wouldn’t leave the house. Heck, he’d barely leave his
room. He’d suffer severe depression. In essence, he was a
different guy entirely.
It always pained me to see him go through these phases of his
life. It sucks watching your best friend on such a roller coaster
with no way to help out. I’m sure acne sufferers and their
loved ones know exactly what I’m talking about.
So when Dr. Alan Logan shared his latest research with me, I
knew I wanted to help spread the word.
Alan is a naturopath and lecturer in Harvard’s mind-body
medicine courses. He studies how nutrition and lifestyle can impact
everything from body composition to brain health to skin health. In
his latest book, The Clear Skin Diet, Alan provides an in-depth discussion
of how nutrition and lifestyle can either worsen acne or eliminate
Dr. John Berardi: To start off, Alan, your name should already
be familiar to the T-Nation audience. The interview you did for us,
Nutrition, Your Brain, and Your Body, got tons of
great feedback. For those who missed the interview, let’s give
everyone a quick glimpse of who you are and what you do.
Dr. Alan Logan: I’m a naturopathic physician, trained in
Toronto, with a focus on nutritional medicine. As we discussed last
time, I’m not into healing crystals, putting pyramids over
people’s heads and all that other wacky stuff. Instead, my
primary business is research of the nutritional sciences and
translating it into clinical considerations.
Dr. Berardi: Although some naturopaths are pretty out there,
you’re as well-referenced as they come. And I’m always
impressed with your ability to see the connections between
different fields of study.
Dr. Logan: It pretty much comes with the territory since I walk
the line between research and clinical practice. As an invited
faculty member in Harvard’s Continuing Medical Education
courses, I lecture on dietary supplements, the placebo response, as
well as the relationship between food, learning, and behavior. And
I’m big on both the research and on clinical applications of
Dr. Berardi: Okay, let’s talk nutrition then. Around here
at Testosterone, most folks think of nutrition mostly as a means to
improve body composition and improve performance. However, I know
you’re always looking at nutrition in new ways. For example,
in your book, The Brain Diet, you discussed how nutrients can impact
brain health, mood, and behavior. What other novel nutrition
related endpoints are you currently looking at?
Dr. Logan: My more recent investigation, spanning the last two
years, has been focused on the relationship between dietary
choices, specific nutrients, and skin health. More specifically, it
was an investigation of the relationship between diet and acne.
As a result of this research, I collaborated with Boston
dermatologist Dr. Valori Treloar and we turned over every
nutritional and lifestyle stone imaginable in our exploration of
acne. The end result is our new book, The Clear Skin
Dr. Berardi: I read an advance copy of The Clear Skin Diet and noted that you’ve pretty much
called out mainstream dermatology with your controversial theories,
especially with respect to nutrition.
Why is there so much in-fighting in the field. I mean, doesn’t
everyone who’s nutritionally aware already know that certain
foods trigger acne symptoms?
Dr. Logan: You’re right, John. International studies show
that the majority of those with acne believe that diet is a
significant factor. Doesn’t matter where you conduct the
research — Asian nations, Europe, the Middle East, United
Kingdom, North and South America — participants always cite
diet as a factor.
The controversy surrounds the fact that these people have been
told by dermatologists for the last thirty years that they’re
wrong! And I can’t blame the dermatologists because that has
been their only training. It’s been etched into the textbooks since
the early 1970s through today, and they clearly state that there’s
no relationship between diet and acne.
The justification for dermatology relegating diet and acne to
“myth” status is a complete house of cards, held up by the shakiest
of foundations — two horribly designed studies from 1969 and
1970. These studies wouldn’t even see the light of day if we
tried to publish them today. I’d get laryngitis if we had a
detailed conversation on the design flaws. In short, they were far
too small, far too short, and one didn’t even have a control
Dr. Berardi: These were chocolate studies, right?
Dr. Logan: You’ve got it. They were designed to determine
whether chocolate ingestion was related to acne. And like I said,
they’re not worth the paper they’re printed
The first study failed to include a control group, among other
design flaws. And the second study that did use a “placebo” control
group had a major, fatal flaw. You see, the “chocolate group”
received a standard chocolate bar with its high saturated fat and
sugar content. But the placebo group got a look-a-like bar where
the saturated fat was substituted with — wait for
it — hydrogenated vegetable oil, the latest food invention that
was all the rage in 1969.
Why’s that such a problem? Well, today we know that
hydrogenated vegetable oils are beyond unhealthy and well capable
of promoting inflammation in the body. And inflammation is a major
cause of acne.
Beyond the fat usage, the most colossal blunder of the two
studies was that neither one took into account the background
diets. In other words, in addition to the chocolate, we have no
idea what anyone was eating or drinking during the “study.” Who was
consuming milk, soft drinks, fried foods, processed foods? We have
no clue about consumption! It’s absurd!
Yet, here they were, these studies, inked into the annals of
dermatological “sciences” and teaching. And unfortunately, for
whatever reason, the door of investigation was slammed shut on diet
and acne, leaving patients completely invalidated.
As one dermatologist actually wrote in the American Family
Physician journal in 1971, “Too many patients harbor the
delusion that their health can somehow be mysteriously harmed by
something in their diet.”
Dr. Berardi: Wow, what unbelievable arrogance we see in that
quote right there! So as a tribute to that dermatologist,
let’s discuss chapter two of your book. In this chapter
you’ve included one of the greatest expository pieces
I’ve read to date on how limited the average medical
student’s nutrition training can be. What’s up with this
and why does it piss you off so much?
Dr. Logan: The average person would be shocked at the sad state
of affairs that is nutritional training in our medical schools. It
does upset me because people with chronic illnesses look to
physicians for guidance on nutritional matters, assuming that they
are well versed.
In truth, only 30% of medical schools require an actual
nutrition course, and even this is almost exclusively related to
intravenous nutrition and biochemistry of the cells. It’s not
the clinical stuff.
According to a study last year in the American Journal of
Clinical Nutrition, 78% of graduating medical students didn’t
feel that they were extensively educated enough to provide
appropriate nutritional counseling. In their patient contact hours,
only 17% had frequently counseled patients in nutrition.
The real problem is lack of accountability. For my license to
practice I had to take separate board exams in biochemical and
clinical nutrition. For MDs, it’s a different story. Only 3%
of medical board exam questions are even remotely connected to
nutrition. Why study it, why learn it, why make the effort if
you’re not going to be tested on it?
And so it goes. For students in the world of pharmaceutical
drugs and surgical techniques, nutrition becomes the stuff of home
Dr. Berardi: You know, I was particularly surprised by the
studies published in Nutrition Journal showing the
1. Nearly 25% of medical students didn’t know that fat
contains, gram-for-gram, more calories than an equivalent serving
of protein or carbohydrates.
2. Nearly 50% of the students were unaware that olive oil is
rich in monounsaturated fat.
3. Nearly 50% of the students thought that folic acid (B9)
supplementation can make up for a B12 deficiency.
Dr. Logan: It’s a bit shocking, but once again, it’s
reflective of a broken system. It’s pretty easy to fix this. A
little less influence by Big Pharma on setting the curriculum and
even just a little more on nutrition and lifestyle, even just the
basics, would be a good start.
Dr. Berardi: Plus it’d be nice if the medical students
themselves actually knew something about good nutrition personally.
Dr. Logan: Absolutely! At present, medical students are hardly
the poster children for healthy eating. Only 11% of them meet even
the minimum five servings of fruits and vegetables!
Dr. Berardi: Okay, let’s quit picking on the field of
medicine. After all, despite these flaws, there are some great
things happening in medicine every hour of every day. Getting back
to the subject of skin health, in your book you present the case
that our current diets may be to blame for the increase in both
adolescent and adult acne over the last 50 years. What do you think
the biggest nutritional culprits are?
Dr. Logan: It’s the same old chestnuts: processed foods,
too much inflammation-promoting vegetable oil, saturated and trans
fats, too much sugar, soft drinks and, in particular, too much milk
[Editor’s note: We asked John Berardi to clarify the
note about the adverse effects of milk. Here’s how he
“Some think it’s the hormones in the milk (either growth
hormones,reproductive hormones, or other growth factors).
Some think it’s because milk may stimulate androgen production
(with milk containing 4 precursors to DHEA – which is considered
“the acne hormone”). And some think it’s due to the insulin
release associated with milk (high insulin is linked with acne).So
it’d be safe to clarify Dr Logan’s caution about dairy and direct
it at milk specifically, and not milk-based protein
The flipside of a diet top heavy in these foods and beverages is
the absence of acne-protective factors: fiber to stabilize blood
sugar, antioxidants from colorful fruits and vegetables, not enough
omega-3 fatty acids, and low intake of specific anti-acne nutrients
like zinc, selenium, and chromium.
Dr. Berardi: So, dietary displacement — making
room for more junk foods by removing healthy foods — is
really to blame.
Dr. Logan: In no small part, yes. And the background to our
position in The Clear Skin Diet is the documented increase in acne in
peoples who’ve adopted a Western diet.
The Inuit of Alberta, Canada, and the Japanese are examples of
where changes in acne rates coincide with processed foods,
unhealthy fats and the like. A study in the Archives of
Dermatology in 2002 blew the doors wide open on the acne-diet
It was Dr. Loren Cordain of Colorado State that deserves full
credit as it was he who led this study. T-Nation readers may know
him by his best-selling book, The Paleo Diet.
What they found was that in isolated hunter-gatherer type
communities in the Pacific Rim and in Paraguay, there were
virtually zero signs of acne, hardly a blackhead to be found. These
populations were separated by some 10,000 miles, yet the common
threads were diets with almost no processed foods, no dairy, lots
of vegetables, fiber-rich roots, high omega-3 intake, and very
importantly, an overall diet that had a low glycemic load. In other
words, the totalities of the diets were such that they would not
spike blood sugar and insulin levels.
Following this there were two separate Harvard studies that
showed clear associations between milk consumption and the
development of acne. Other forms of dairy were also implicated,
including ice cream, sherbet, and cheeses.
Interestingly, yogurt wasn’t a culprit, perhaps because the
bacteria alter the structure. These bacteria may also play a direct
role. We found two international studies and had them translated,
one from Russia and the other from Italy. Both showed that oral
administration of the so-called friendly bacteria, or probiotics,
Moving forward you have to conduct clinical trials, intervention
studies in a controlled fashion. It’s tough to do in acne, but
researchers from Australia pulled it off.
In August 2007, two separate studies were published, one in the Journal of the American Academy of Dermatology, and the
other in the American Journal of Clinical Nutrition. The end
results in both was that a diet high in lean meat, fiber, healthy
fats, and lower in saturated fats, simple sugars, and processed
foods significantly improved acne over three months vs. controls.
In fact, there were about 22 less acne lesions in the healthy diet
group. That ain’t bad at all.
Overall the diet was similar to the hunter-gatherer approach,
one with the same anti-acne low glycemic load that Dr. Cordain had
discovered in 2002. By the way, the participants were completely
unaware that this was an acne study per se; they thought the
investigation was to see if changes to protein/carbohydrate ratios
might influence some blood markers.
Dr. Berardi: Beyond Dr. Cordain’s studies, you present an
interesting comparison between the Japanese and North Americans
with respect to diet and acne prevalence. What’s the
Dr. Logan: Well, in 1964 there was a large comparative study in
acne rates between Japanese teens living in Tokyo and Yokohama vs.
American teens in urban centers. The rates of acne were 50% less in
Japan. At the time it was written off to genetics.
Problem with that is today the rates of acne in Japan and North
America are the same! We’re fortunate that international record
keeping from the World Health Organization allows us to go back in
time and compare the diet in Japan in 1964 vs. today. As you might
imagine — massive increases in saturated fat, milk intake,
vegetable oils, sugar, and processed foods. This combined with a
more sedentary lifestyle.
Dr. Berardi: But what about genetics? Obviously nutrition
isn’t the only factor involved in acne. What other lifestyle
factors, genetic factors, etc. can promote a worsening of acne
symptoms and breakouts?
Dr. Logan: You’re right; diet isn’t everything in acne.
Really, we may have wanted to call the book The Clear Skin Lifestyle.
Research has shown that stress can lead to flare-ups of acne.
For example, exam stress and relationship breakups have been
associated with a worsening of acne. I’d speculate that work stress
in our modern world is also a contributor. Cortisol, the stress
hormone, promotes sebum production which can increase the risk of
blocking up the pore.
Genetics are, of course, a major factor. But they too aren’t
everything. And we now know that diet and lifestyle can influence
genetic expression. That is, whether or not you get an illness, or
the degree to which one experiences an illness can be mediated by
environmental factors despite shared genetics.
As with most chronic illnesses, in acne you have this bell curve
thing. At one end are those who could eat fast food daily, have
poor sleep and tons of stress, yet have superb skin. At the other
end there are those with severe acne who might do everything right,
eat a stellar diet, keep stress in check, and yet see only marginal
differences with these efforts. The bulk of those who experience
acne are in the middle.
John, our genetics haven’t changed in the last 40 years, so they
can’t be used as an excuse for the documented, significant
increases in acne rates among university students, professional
women, and other adults. Can’t write it off with the genetics
card, and it’s not because the diagnostic criteria have
changed either. We simply have to look to the environment — diet
and stressors top the list.
Dr. Berardi: Well, all of these lifestyle and nutritional
considerations certainly help explain the story I shared with you
earlier. My roommate suffered from severe acne breakouts whenever
he was having any substantial stress — whether it was sport,
school, or relationship stress.
Dr. Logan: Hormones — cortisol!
Dr. Berardi: Right, and due to this stress, he’d eat lots of
sugar and inflammatory junk foods.
Dr. Logan: And there’s the dietary link.
Dr. Berardi: In the end, what could he have done to prevent
Dr. Logan: Well, he could have managed them by keeping stress in
check and exercising. Also, practicing meditation, mindfulness, and
other stress management techniques are important.
Finally, quality sleep is critical. Most acne patients report a
worsening of acne when they don’t sleep well on a regular
basis. Of course poor sleep elevates the stress hormone cortisol
and changes our dietary habits to one of unhealthy comfort
Dr. Berardi: Speaking of food, what about on that front?
Dr. Logan: It’s pretty simple. To manage acne the diet
should be rich in lean protein sources, fish, poultry, eggs, game
meats, or very lean beef.
Also, saturated fats should be controlled while trans fats
avoided, and so should processed carbs and sugars. To this end,
make sure to check labels. For example on cereal, choose the one
with the lowest grams of sugar and highest grams of fiber.
Tomato may also be a specific anti-acne food since the lycopene
in there can lower an acne-promoting hormone. Green tea is the
beverage of choice since it limits the formation of
dihydrotestosterone (DHT) via Testosterone, and DHT is a much more
potent acne promoter than Testosterone.
Also, to manage acne, you should maximize your omega-3 fatty
acid intake, choose canola or olive as the cooking oils of choice,
and don’t forget to color the diet as much as possible with
fruits and vegetables, berries in particular. And very importantly,
Dr. Berardi: Basically what many Testosterone readers already
Dr. Logan: For sure. I know the T-Nation nutritional IQ is very
high. After my last interview and the banter we had back and forth
on that thread, I have no doubt that T-Nation readers would ace the
3% of nutrition questions on medical board exams.
Of course, T-Nation knows that Dr. Treloar and myself haven’t
discovered plutonium by accident here. It’s not like we were
the first to split the atom. Overall, this is the same healthy diet
that’s been recommended for cardiovascular disease and diabetes.
However, there are subtleties with this anti-acne diet that are a
Dr. Berardi: For example?
Dr. Logan: The nutritional demand for zinc is high in acne; zinc
levels have been shown to be low and oral supplements are helpful.
Chromium is also important. An older study showed benefit with
oral supplementation, probably because it helps regulate blood
sugar and insulin levels.
Selenium is another one. There may be an additional burden in
acne because a particular antioxidant enzyme, glutathione
peroxidase, is hard at work in the skin of acne patients and it
won’t work without selenium. The selenium levels have been
shown to be low and oral supplementation has been shown to be
This antioxidant story in acne is surprisingly significant and
underappreciated. Those with acne have lower levels of antioxidant
nutrients in the blood, and the more severe the acne, the lower the
The omega-3 connection to acne is such an emerging story because
we now know that these fats, and the EPA from fish oil in
particular, can put the brakes on the formation of an inflammatory
chemical that’s otherwise a major sebum producer.
So supplementation with EPA, zinc, selenium, and chromium may be
helpful. In fact, Genuine Health Inc. of Toronto, Canada, has put
these ingredients together in capsule form, along with green tea in
a commercially available supplement called Perfect Skin.
Dr. Berardi: But what about commercial, topical products —
you know, the ones that seem to be making all the folks happy on
the infomercials? Why focus on nutrition when these are
Dr. Logan: There do seem to be an unusual amount of acne-curing
miracles on TV these days. Over-hyped commercial products as
promoted by celebrities are nothing more than well packaged and
marketed ingredients that have been available over-the-counter for
years: benzoyl peroxide and glycolic acid.
Clinical studies, which apparently didn’t include these
miracle-cure participants, show moderate results for benzoyl
peroxide. It’s far from a cure. As for glycolic acid, almost
nothing is known about its effectiveness at the low levels used in
products as hawked by celebrities. At doses used by dermatologists
— far, far higher than that in the hyped products —
preliminary research suggests it may provide some
However, why place a band-aid on the problem with these “cures.”
Why not fix the problem from the inside out while boosting
nutritional status and overall healthfulness of the diet at the
Dr. Berardi: And while we’re on the topic of other
remedies, what about the stuff that seems to make everyone really
sad — Accutane?
Dr. Logan: As for Accutane, it’s a very, very effective drug for
acne. However, there are significant risks of birth defects in the
offspring of female users should they become pregnant while on the
Also, the medication is mired in controversy and it does have a
virtual laundry list of adverse events that have been reported in
the medical literature. Most notable are the depressive symptoms
and association with suicide.
It’s interesting, because the very nutrients that may be
low in acne — omega-3 fatty acids, zinc, selenium, and
chromium — may be influencing the high rates of depression in
cases of acne. Of course, the appearance of the skin is the driving
force, but the nutrient connection with acne depression has been
Dr. Berardi: Wow, another link to my buddy’s story.
He’d suffer severe depression when he’d get his
breakouts. What’s up with that?
Dr. Logan: The omega-3 and depression story is becoming more
established by the month, to the point where in December 2006 an
American Psychiatric Association committee recommended the use of
fish oil supplements as an add-on to
standard care in depression.
At least five studies have shown that low selenium levels are
associated with lowered mood states. Zinc in low levels has been
associated with depression many times and new research with oral
zinc supplements shows improvement in depressive symptoms.
Two recent studies show that chromium supplements help with
various aspects of depressive symptoms. The point is that nutrients
may be playing a bigger role in the emotional fallout of acne than
Dr. Berardi: The same deficiencies may be causing acne and
depression! I wish I would’ve known this stuff a few years
Well, Alan, this interview has been really interesting and has
helped explain a lot of my own experiences with acne. I’d like
to wrap up the interview with the following
the typical T-Nation reader prioritizes muscle mass and
strength, prioritizes high Testosterone levels, trains with high
volume and intensity, sweats hard and often, and eats a high
protein diet. What’s the prognosis, doc?
Dr. Logan: The good news for T-Nation readers is that the new
acne studies were based on a high protein diet, lots of lean
protein. Lean beef, poultry, and fish were
Since this type of diet is usually the staple of those who are
all about building and maintaining lean mass, I think most T-Nation
readers are likely doing well from a baseline diet
I should also point out that the acne preventive test diets were
also significantly higher in fiber and lower in saturated fat. That
is a natural fall-out from a diet where the carbs are fiber rich
and fruits and vegetables are encouraged.
In the end, this typically leads to a small reduction in
insulin-like growth hormone (IGF-1) and Testosterone. Now,
it’s not nutritional castration, but it’s significant enough
to make a difference in hormonally driven diseases, like acne and
For example, a Harvard study that followed men over time
discovered that men who go on to develop prostate cancer have an 8%
higher IGF-1 level vs. men who don’t subsequently develop prostate
cancer. These are small but significant differences.
Dr. Berardi: Uh-oh!
Dr. Logan: For most, there will be little to no conflict with
these healthy changes and the maintenance of lots of lean body
mass. For those who wouldn’t dream of giving up even one half
of one percent of Testosterone levels through diet, at the very
least eliminate dairy as a first step toward improving acne. Then
maximize fish oil intake, maximize your antioxidant intake, drink
green tea, and consider supplementing with the nutrients discussed
— zinc, chromium, and selenium.
Dr. Berardi: Awesome, Alan. Great stuff! Thanks for the
interview and keep us up to date on your latest
Dr. Logan: Will do!