Transcriber: Tanya Cushman Reviewer: Rhonda Jacobs
All right - raise your hand if you're on a diet,
you've ever been on a diet
or you avoid eating specific foods for a reason.
Oh. That's a lot.
Well, you're not alone.
Since Hippocrates' dietary advice of, among other things,
eating fatty foods to feel fuller faster
and vomiting once a week,
which apparently was fashionable at the time,
to Cleopatra's famous beauty regimes
of eating pulse and water for 10 days straight
and bathing in fermented milk
to Lord Byron's obsession with his image and body weight,
which eventually turned him anorexic
when his diet of flattened potatoes drenched in vinegar
was no longer bearable.
Since recorded history,
man has always been on some kind of a diet.
And today, more than half of Americans
try to take some control over the healthfulness of their diet.
In this modern world,
there's no end to the variety of diets out there,
all offering some kind of nutritional benefit
if not at least weight loss.
I like this one that says,
"Follow the DASH diet
to 'potentially' lower your blood pressure."
(Laughter)
But whether you call it a diet or a lifestyle change,
how do you know if it's effective in what you're trying to accomplish?
Dieting is already notoriously difficult for most people.
In fact, most people think it's easier to do their taxes
than to figure out how to eat healthfully.
Last century, we were able to send a man to the moon.
We were able to figure out how to send instant messages over cyberspace.
We were even able to figure out how to splice genes from one species
and place them in an entirely different species.
But in this 21st century,
why cannot we not figure out how to eat?
Why can we not get this nutrition thing right?
Maybe it's because
we don't have one reputable source of nutrition to turn to.
We turn to doctors for questions about our health,
but most doctors admit to not being adequately trained in nutrition.
So where do we turn to next?
Tips from glossy magazines,
sensational headlines in the news,
maybe even the health claims on products in the grocery store.
This leaves the door open for anybody to be able to claim anything about diet.
And indeed, there's an entire industry around dieting, nutritional advice,
health and obesity and free-from foods.
Now, I'm not saying that every person out there with nutritional advice
is some kind of charlatan.
But more often than not,
those nutritional claims that are the loudest,
most marketed, best funded
are the ones that we usually hear.
And sometimes there just isn't sufficient scientific data
to support one claim over another.
But there are cases where the data is numerous -
sometimes even overwhelming.
And our nutritional and medical organizations
are completely disregarding it.
Take the example of obesity.
Since this Time magazine cover
30 years ago,
advice to cut out fat and cholesterol has been ubiquitous.
And has it helped?
Unfortunately, no.
Rates of obesity have actually skyrocketed since then.
And today, two out of three people are overweight or obese.
Is this because Americans are getting more and more gluttonous
and less and less disciplined?
I would like to give us more credit than that.
For hundreds of years,
it's been assumed that if we eat too much, and especially too much fat,
that's how we get fat.
But instead, when people started to look at the mechanisms,
the biological mechanisms behind fat accumulation,
back in the 1930s,
they started to see a completely different picture.
It turns out that it's carbs that make us fat,
and specifically the insulin that's released when we eat carbs
that make us fat.
So when you eat sugar from a carbohydate-loaded meal,
your body produces insulin
in order to regulate that sugar in the bloodstream.
It does this by telling the body to store fat from the meal right away,
use any glucose from the meal right now for fuel,
and if there's extra glucose, you can store that as well.
Once the meal has been digested
and you've used up all that free-roaming glucose,
then you can start burning fat.
But when fat is stored in this system, it's stored as a triglyceride,
made up of three fatty acids.
That triglyceride is too large to pass through the cell membrane.
So in order to burn fat,
you have to break down this triglyceride into its three fatty acids.
This is important
because not only does insulin signal the body to store fat and glucose,
it also inhibits the breakdown of these triglycerides.
So as long as insulin is flowing, it is extremely difficult to burn fat.
Now, this was nature's design -
to be able to store fat to be used at a later time:
for instance, when we're sleeping
or in the case of a run-in with a saber-toothed tiger
and we need an extra adrenaline boost.
(Laughter)
Fat flows in and out of our body as needed
unless this delicate regulatory system
gets imbalanced.
If we continue to secrete insulin
before we burn the fat from previous meals,
then we will only continue to store more fat,
and those triglycerides will never get broken down.
So to be clear, the more carbs we eat,
the more sugar enters our bloodstream.
The more sugar enters our bloodstream, the more insulin is produced.
The more insulin is produced, the less chance we have of burning fat.
Understanding the biological mechanism behind how fat accumulation works
means that we can actually
take the guesswork out of what kind of diet will be most effective
when trying to achieve weight loss.
We almost don't need studies that show the efficacy of a low-carb diet,
but we have them.
We have lots of them,
and this is just a sampling of some recent studies that have come out
that have showed that low-carb diets
are significantly more effective for weight loss than low-fat diets,
sometimes two or three more times effective,
and in fact, some of them actually help to reduce the bad cholesterol.
But still, our national nutritional organizations,
including the USDA,
whose dietary guidelines are far reaching,
are still telling us to cut fat from the diet.
And the only milk that's allowed to be sold in school cafeterias
is low-fat milk with added sugar.
(Sigh)
Time magazine finally caught up with the science
30 years after their original admonition,
and we can only hope with this latest study in the Lancet,
published last month,
that our national nutritional organizations will finally start to see
that their assumptions on what make us fat are antiquated.
Unless, of course, the food industry has any sway in these dietary guidelines.
I like that:
"No wonder Pop Tarts count as a whole grain."
(Laughter)
So another case where the science behind the diet is shocking
is with the gluten-free diet.
But what's not shocking about the gluten-free diet
is that more and more people are eating gluten-free these days,
because, in fact, celiac disease
is four times more prevalent than it was 50 years ago in the US
and four times more prevalent in the UK than it was 20 years ago.
And despite what mainstream media says,
non-celiac gluten sensitivity is actually a legitimate medical disorder,
and it's associated with gut inflammation, autoimmunity,
a very serious brain disorder called gluten ataxia - among other things.
And it's thought that about 12%, at least, of the population has gluten sensitivity,
or about 38 million Americans,
which is 10 times more than those that have celiac disease.
So it's not shocking
that more and more people are going gluten-free,
but what is shocking
is that the gluten-free diet actually has a very poor track record
when it comes to healing the guts of celiac disease patients.
In a study published in the journal Alimentary Pharmacology & Therapeutics
in 2009,
researchers found that only 8% of patients ever completely heal their guts.
Now, I thought this statistic was staggering,
and I don't understand why more people in the gluten-free community
aren't talking about it.
Instead, what you hear
from prominent authorities on celiac disease
is that the majority of the time
patients do respond positively to the diet.
They say about 85 to 90% of their patients respond positively.
That's completely opposite of what this study found,
so I wanted to know how can this be.
Well, it turns out it depends on how you measure response to the diet.
So those that are saying an 85 to 90% response rate
are measuring the response clinically:
their patients' symptoms improve.
They feel better, so they're having a positive response.
But, of course, feeling better is a pretty subjective way
to measure a response,
and indeed numerous studies have shown that a positive clinical response
does not indicate that the patient has actually healed their gut.
When researchers looked at the histological response to the diet -
that is, they took biopsies to see if the gut had healed -
that's when they saw a completely different picture.
Now, I thought that - I was hoping that maybe this 8% recovery rate
was a one-time anomaly,
but I went back to the medical literature and I found similar studies:
in this study, only 17% ever healed;
21% recovery rate; only 30%;
only 37% ever healed their guts.
Maybe not quite as dire as that first statistic that I threw out,
but still, no matter how you look at it,
the vast majority of celiacs are not healing on the gluten-free diet.
And this is important
because if celiacs don't heal their guts,
they are susceptible to a whole host of life-long chronic conditions
called "comorbidities" in the medical literature.
Some of these are life threatening.
This is also important for those that have gluten sensitivity
because it's been found that people that have gluten sensitivity
actually have a higher mortality rate than those that have celiac disease,
presumably because most people
are not taking gluten sensitivity seriously enough.
So, of course, the big question is why isn't the gluten-free diet working?
And I can tell you from my research
there are many different pieces to that puzzle,
but unfortunately,
doctors and patients don't even know to ask this question,
because authorities are still saying
that this is the best treatment for celiac disease and gluten sensitivity.
And one of the most shocking pieces of the puzzle to me
is, yet again,
another place where the science and the authorities aren't matching up.
In 2013, the FDA passed a law
that says if you want to label your food gluten-free,
you have to less than 20 parts per million of gluten in the food,
which means, of course,
you can have up to 19 parts per million of gluten in a gluten-free food.
They based this guideline on just one study,
where the authors of the paper said that measurable damage doesn't occur
until a celiac patient eats 50 milligrams of gluten a day.
And they equate that 50 milligrams to saying
if you ate several foods a day with less than 20 parts per million of gluten in it,
you would never reach that total of 50 milligrams in a day.
However, in 2011, the FDA itself did its own meta-analysis
that looked at all the medical literature out there
that examine the safety threshold of gluten,
and what they found was completely different.
They found that symptoms started
with as a little as 0.15 milligrams per day
and that intestinal damage began at less than half a miiligram per day,
not the 50 milligrams that that one paper said.
And so they equate this to less than 1 parts per million of gluten
being the safest for those most sensitive to it.
Or let's just call it zero.
So, why would they go with that one study rather than their own meta-analysis
when they decided to pass that law?
Well, I hate to say it, but because, once again,
the food industry has probably had a little bit more sway on this decision
than should be allowed.
You don't even have to read between the lines in this letter,
called "In Defense of 20 Parts Per Million,"
where he says that if US manufacturers
are forced to abide by an unnecessarily restrictive safety threshold,
they would not be able to compete successfully
in the gluten-free global marketplace.
For over 100 years, we've been told that the gluten free-diet
is the best treatment for people with celiac disease,
and we haven't thought twice about it.
And now, today, most celiacs and the gluten sensitive
are replacing their gluten-containing foods
with foods from the free-from aisle,
which may alleviate their symptoms temporarily,
but in the long run, it's not going to help them heal.
And yet, gluten-free business is making billions of dollars a year.
And in fact, a lot of people get their nutritional information
from the gluten-free expos instead of from their doctors.
So, why can't we get nutrition right?
Or can we?
I don't think it has to be this way.
We have the capacity to figure this out,
but we need to make a concerted effort.
We need to be able to fill in the gaps
in what we do and don't know about nutrition,
with more rigorous science.
We need control studies comparing one food to a control group,
and these studies need to completely isolate that one food
so there's no question
that that food is the one thing that's causing that effect.
This food needs to be evaluated
on specific physiological effects on the body,
not just the likelihood that it might have caused cancer
because subjects who ate it died of cancer many years later.
And yes, I'm talking about the recent disconcerting news, once again,
from the World Health Organization,
that eating meat causes cancer.
They actually based this statement
on epidemiological studies that are almost 10 years old
in which they had asked their subjects
to simply recall what they had eaten at an earlier time.
And they did not isolate the meat from anything else,
so was it the ham, the ham sandwich,
the [glucose] sugar, the additives in the ham?
We don't know.
Here's a case where there was no science
and yet the authorities were telling us something different.
So we need to conduct this research independent of the foods industry.
And we need our doctors to have better nutritional training
and a better understanding of the actual physiological effects
that food has on us when it enters our system.
There are some doctors that are trained in diet and nutrition;
they're in a branch of medicine called functional medicine,
and that's great.
The only problem is that, unfortunately, at this time,
their visits are not usually covered by insurance,
so sound, basic dietary advice is still inaccessible to most people,
and I hope that changes one day.
Of course, for somebody trying to figure out
their own personal nutrition,
you can't wait decades to find out what randomized control studies
are going to tell you about what to eat or not eat.
(Laughter)
That's when I say be your own scientist.
You can learn a lot just by observing your own body.
You probably already have some clues
as to whether or not your diet is working for you.
You can monitor symptoms, keep a food journal if it helps.
You can even conduct your own research if you're up for it.
PubMed is a free service, open to anybody,
and with a little bit of determination and patience,
you could probably break down some of the medical jargon,
depending on the paper.
And there are, actually, a few organizations out there right now
that are working on independent, unbiased research
in education in nutrition,
so you can follow their work as well.
I am certain, with a concerted effort,
that both on a personal and a national level,
that we can get diet and nutrition right.
Thank you.
(Applause)