Tom Zinnen: Welcome, everyone, to Wednesday Nite at the Lab. I'm Tom Zinnen.
I work here at the UW-Madison Biotechnology Center. I also work for UW Extension Cooperative Extension, and on
behalf of those folks and the other partners at Wednesday Nite at the Lab, Wisconsin Public Television, Wisconsin Alumni
Association, and PLATO and the UW-Madison Science Alliance, thanks again for coming to Wednesday Nite at the Lab.
We do this every Wednesday night, 50 times a year. Tonight, it's my pleasure to introduce to you
Dr. Dale Schoeller. He's a professor of nutritional sciences here the UW Madison, and he's an internationally
recognized expert in energy metabolism and body composition. He's best known as the first person to use the doubly labeled
water method for the measurement of energy expenditure in humans. He has performed extensive research in human obesity.
I don't know why he hasn't contacted me. [LAUGHTER] This includes studies of the
role of physical activity and energy intake in the ideology or cause of obesity, the comparison of obesity
treatments to improve efficacy and development of improved methods for measuring body composition.
He's also been instrumental in identifying systematic reporting errors in question error based assessments of energy intake and
physical activity. Which is a big interest of me because my wife does survey design.
That's pretty cool. He's also currently investigating novel stable isotope biomarkers of dietary
intake. I don't speak German and I'm not used to 12 nouns stacked in a row, so I hope you'll explain
what that was to me. Please join me in welcoming Dr. Schoeller to Wednesday Nite at the Lab.
[APPLAUSE] >> Dale Schoeller: Thank you, Tom. How are we on volume?
Is this good? >> Yes. >> All right. Well, let's get started.
Except it's not listening, oh, there we are. Okay, just a little slow. So I'm sure you're all aware
from reading the newspaper that there has been a dramatic increase in the number of obese individuals in the United
States. We can start in 1965 or pretty much skip to '88. There wasn't a huge change from
there, but in about '65, not shown here, about 10% to 12% of adults were classified as obese. By 1980 it was up to where some
states, especially in and around Wisconsin, were between, put on my glasses, 10% and 14% of the adults obese.
1996, most states in the Union were over 10%, and many of them running up in the 15% to 20% range.
And then last year when the statistics were taken, 2010, 34% of adults were classified as obese.
And you'll see there's a hot zone, if we can get this listening to me, hot zone down here along the Mississippi River
Delta. And just to put a picture on this, so here we have four generations of a family.
This gentleman was probably in his 20s or 30s in '65 and guessing from his weight now, I would have guessed he'd been a
healthy weight. Probably about 150 pounds. Next generation, he's now overweight.
Current generation adult, in 2008 or so when this picture was taken, just on the obese side, judging from his height and
weight. And, of course, the generation I worry about as an investigator is the next generation after
that. If it continues to get worse, so will our health problems. Just the movement to here, why
is obesity a concern? Well, we're all concerned a little bit how we look but the real concern from a nutritional
point of view is that obesity is a risk factor for a lot of diseases. It increases the risk threefold,
300%, for diabetes, gall stones, high blood pressure, high plasma cholesterol and high plasma triglycerides and sleep apnea or
sleep interruption. It increases the risks two- to threefold for heart disease, osteoarthritis and gout.
Yeah, that one hurts. Fortunately, there's not a lot of it anymore. And it has a slight increase for
risk for some cancers, reproductive hormone abnormalities, polycystic ovary syndrome and back pain and knee
pain, which I know I'm having more and more trouble with. So let's walk through this and you can see the link here for
diabetes. As we go from the 1990s through 2008, increase in diabetes. You'll see below that the
increase in the diagnosed diabetes in the US. And it pretty much follows. Darkened areas fall in the same
area. Obesity increases, diabetes increases. As it increases more, diabetes
even more so. So that now we're up to about 6% to 7%, nationally, of adults have type two diabetes.
And there are probably another 50% more out there who haven't been diagnosed. How is Wisconsin doing?
Not so bad now. When I first moved here, Wisconsin was up here at the high end.
Not so much in terms of percentage but it was one of the more obese states in the Union. And now we're kind of central.
About 26.3% of Wisconsin adults are classified as obese. Leanest state in the nation, Colorado, at 21%.
Most obese in the nation, Mississippi, at 34%. Wisconsin has its hot spots. Milwaukee area, out here a
little bit east of us, go north, go up to the Indian reservations have the highest percentage of obesity in Wisconsin.
And the lowest, I think that's Sheboygan County, and Dane County. Here running about 25% of
adults. But you'll see, again, the same pattern increases in diabetes showing up, again, largely in
Menominee up here and being lowest in Dane County where there's the least obesity. What you are seeing a little bit
in this disparity from state to state is some of the racial disparities. The white non-Hispanics in the
US, about one out of four are obese with most concentration in these states. When you go to Hispanic culture,
people of Hispanic culture, 31% are classified as obese as adults. And among African Americans,
37%. And you see this same pattern where the races concentrate, you see the highest percentages of
obesity. And what I worry about, of course, is not only adults are showing up as obese but this is
the data for children. Be them two- to five-year-olds, increasing from 71 to 74. By definition we classified 5%
of children as obese. Those in the upper weight for their height range. In young children that has
increased about twofold. In 6- to 11-year-olds, it's increased threefold over the last 30-35 years.
And in teenagers also about threefold. And that's a concern because if you are obese as a teenager,
you've got about a 90% probability of being obese as an adult. As a six-year-old, you've got
about a 50% chance. Problems not only here in the US but it's a global problem. This is a colored map of the
world. I don't have the scale on here but orange in the US is that 30% to 35% range for both females
and males. You'll see the US is not the most obese nation in the world in terms of females.
That's here on the Sinai Peninsula. But you'll see increases in obesity globally, Canada,
Russia, through Europe, South America it's increasing, Australia, and it's even starting to show up at about the
7% to 10% range in China in both females and in males. So, energy balance here seems simple.
It's simply the comparison between the number of calories that you eat every day should equal the number that you
expend, and if you're in positive energy balance, if you're eating more than you're expending, you're going to start
gaining some weight, laying down body energy stores. If you're expending more than you're eating, you'll lose some
weight. It seems a very simple concept. What is it, though, that tips this scale?
What's causes actually globally an increase in body energy stores, or call it obesity? I don't have the full answer but
we'll go through some of the ideas that are current. The long debate that's been around actually for hundreds of
years but here I pull a paper from 1995 looking at the obesity epidemic in Britain which also, as in the US from the last 10
years in Britain increased from about 7% to about 14%. It about doubled during that period.
They're actually falling just a few percentage points behind the US. And Prentice and Jebb here
question, is it gluttony, overeating, or sloth? Sedentary lifestyle. And they looked at two sets of
survey questionnaires. One, what do people say they're eating? And plot it against, here is the
increase in the number of obesity adults. And what they see is pretty much a flat line in terms of
self-reported caloric intake. But where they see what's called a secular trend or secular similarity is as obesity is
increasing you're seeing more cars per household, more miles driven, fewer walked and increase in television viewing.
Very sedentary behavior. So they came to the conclusion that the problem for obesity was our sedentary lifestyle, not our
food intake. Well, I didn't bring the data but something that's not right with their dietary reports, and
we'll come back to that, but it's now well-known from our measurements with the doubly labeled water measure of energy
expenditure that energy, and thus energy requirement to stay at a stable weight, increases as you gain weight.
So from that picture that you saw in the United Kingdom with increasing weight over that 10-year interval, we would
predict that intake would increase. So maybe intake has something to do with it.
And, in fact, if you look not at what people tell you they eat in the US, but rather how much food is sold in the US, the number of
calories that pass through the grocery store, you see a very different picture from 1970 to 2009.
You see an increase in the number of calories sold of about 500 calories per day per person. That's a lot of calories.
You'll also notice, and we'll come back to this again a little bit later, where the increase is it's in flour and cereal
products, added fats and oils and caloric sweeteners. Where do you find these foods? Mostly processed foods rather
than fresh foods which are your fruit, dairy, meats, eggs, which haven't changed much in terms of calories sold over the past 40
years. Okay, let's look at some of the evidence now, not on caloric intake which has increased and
could account for that obesity epidemic, but physical activity, which is what you hear a lot about in the press.
Be more active, burn more calories, lose weight. Well, this is one of the best physical activity weight loss
studies that's been done in the US. This was done in about a hundred individuals.
It's what's called a randomized controlled trial. People were randomized either to an exercise regime or a control
regime in which they were not asked to exercise. The exercise was actually supervised.
They had to come into a gym and sign in and be seen five or six days a week and during that visit, perform 400 calories of
exercise. That would be the equivalent of about two hours of a jog at about five or six miles per
hour. And they were allowed to eat an ad lib diet. They were not told this was a
weight loss study. And what you see in the men, this is the control group in the light gray, they held about the
same weight over a period of 16 months. The men in the exercise group lost a little bit of weight,
about two kilograms, peaked at about nine months and then they held that value, about a two kilo weight loss.
That's a lot less than you'd expect for 400 calories per day of exercise. And then the women, which is
always a discouraging thing to see, the control group gained weight, the exercise group at least maintained their same
weight but showed no weight loss. So as an exercise alone intervention, it's not very
effective for weight loss. You did see a little bit of increase in muscle mass, an extra pound in the women and a
loss of fat mass a pound, but weight didn't change much at all. In men, very small weight
change. And what you would have expected for that 400 calories in about 16 months, you would have
expected a loss of about 12 kilograms or about 25 pounds based upon just that simple energy balance equation.
Intake equals expenditure, plus change in body stores. Increase expenditure, you'd have predicted a 25-pound weight
loss, and in men what you saw was maybe five. In women, no weight loss. Let's take a look at another
study. This is one I was involved in with Amy Luke, Loyola University in Maywood, Illinois.
She did a cross-sectional and longitudinal study in two locations. One, Ghana in Africa where the
obesity rates are still less than 10%. >> That's Nigeria, actually. >> Ah.
It's Nigeria Cameroon. >> It is Nigeria. Thank you. The study we're doing right now
is in Ghana which is over here. That is Nigeria, thank you. And I even have that up here. And compared that with Maywood,
Illinois, where the obesity rates among the women who were studied were about 35%. There were very different
weights, I didn't bring that data. There were very different percent fats, but let's look at
the relationship between the amount of calories that they burned in exercise. So they're activity energy
expenditure which includes everything from getting up, walking across the room to planned exercise.
Although in Nigeria they don't do much planned exercise. It's largely labor involved in their regular work day.
But if you look at body mass index here versus activity energy expenditure which was adjusted for their body size, no
relationship. The more activity energy expenditure they were no more or less obese in terms of their
BMI. See the same picture in Maywood. It's boosted up a little bit because this starts at a BMI
of 20, a healthy weight. This one at 15, which is underweight. It's boosted up a little bit
above this. Overlays here but no cross-sectional relationship between the two.
And more importantly, she brought each of these subjects back about two to three years later, depending when they could
schedule them back in the clinic, and saw no relationship between their activity energy expenditure, this time not in
calories but in megajoules, and their weight gain over that period. In fact, the weight gains
between the two populations were very similar, .6 kilograms per year in Nigeria, .5 in Maywood.
Again, no protective effect of being on this upper end of physical activity against weight gain.
Children. Here we collaborated with Mickey Stunkard in Philadelphia in what he called the infant growth
study. This was a study in 45 infants who had their energy expenditure measured by our doubly labeled
water technique at three months of age, two years, four years and six years. And then we calculated their
BMI, their weight over height squared, at age eight and used what's called a Z score, measured how far away it was
from the average in that age group. What you see in terms of energy expenditure, here each point
represents one measured energy expenditure, and it is adjusted for body size because these kids are growing.
Each time they come back, they're getting a little bit bigger. So we have to plot their body
size against their energy expenditure and figure out if they're above the line or below the line.
And you will notice that there is indeed a tendency for those who measured at one time to be above the line, their average is
usually above the line over here. For those who have low energy expenditures, they tend to stay
below the line throughout. So there is reproducibility across this dramatic change in age and body size, but when we
look at their energy expenditure, these are the ones who are below the average line. These are the ones that are
above that average line. If we look at that against their BMI percentile, or their BMI Z score, where they fall at age
eight, we see absolutely no relationship. So the children with a high energy expenditure are no more
likely to be at a high BMI than those with a low energy expenditure and the other way around.
No relationship. So, the basic thought with activity energy expenditure and exercise, and this is actually
from Donnelly again who did that nice intervention study where he added 400 calories per day in physical activity in the women,
it was actually 600 in the men, is that they increased energy expenditure but body weight didn't change much so it must
have been countered by an increase in energy intake. They did measure energy expenditure in a subgroup and
did show that it went up. Reason for that, of course, is that the energy balance equation isn't just that simple.
If you change energy expenditure, what happens? You get hungry because we have a marvelous control system to
regulate our body weight. You start to burn off fat, you increase the hormones circulating through your body
which feed back to your brain and say I'm hungry. If you become more sedentary, you start laying down fat, you
signal the brain to eat less. It works pretty well. Not perfect. So this energy balance equation,
while simple and correct according to every law of physics, energy can't be created, it can't be destroyed,
so the energy balance equation has to work. But it's not so simple that you can just increase or decrease
energy expenditure a little bit and expect to change or increase or decrease energy intake a little bit and expect to change.
Because we have all these feedback systems. Our hunger and satiety on this side.
We have an effect of body weight. If you're overeating and gained a little bit of weight, well,
you're a bigger body so you burn more calories. Both of these things try to keep the body at about the same
weight. Now, what I don't want to say, well what I do want to say is that don't expect a huge effect
on body weight if you start an exercise program. But what I don't want to say is don't do that exercise.
It's important. One, adding exercise, and this is Donnelly's experiment showing individual weight changes with
that added exercise. I want you to notice there's a lot of variability. For some people adding exercise
works. Here's a loss of about 10 pounds in one woman. And in one man down here he lost
30 pounds during that period. Now, we don't know why there's this much variability. We don't know if it's genetic
and the differences in the feedback system or if it's behavioral. My personal hypothesis is that
people that lost weight probably entered that exercise saying, boy, if I'm doing all this exercise I'm going to lose some
weight and they watched their diet. Where the people up at this end said, boy, I'm doing that
exercise, I don't have to watch my diet anymore. But that's a theory. Only a theory.
So another study which shows the benefit of exercise, this is a study in individuals over 65 years of age, a one-year study,
in which the subjects were randomized into four different groups. A caloric restriction of about
500 to 700 calories per day, exercise with not a caloric restriction but just a maintenance diet but they were
exercising about three times a week for a 90 minutes, combination of aerobic exercise on the treadmill or exercise
cycle or weight training, a group that combines both the diet with the exercise, and then a control group which we're told
don't do anything to change your weight. And what I want to show you here is not the weight change.
The weight changes between the diet exercise and diet groups were about the same, but what I want to show you is their
fitness level as measured by VO2 max, the maximum amount of oxygen that they can pull into their lungs and utilize.
And what you see compared to the control group, the control group went down a little bit. They were less fit.
Exercise group, well, let's actually look at the diet group first. The diet group, their fitness
went up. That's a weight effect because the VO2 max here is presented as the amount of oxygen that you
consume per pound of weight. That diet group lost some weight so it was largely an artifact that this number went up.
The exercise group didn't lose much weight but their fitness went up, and this is a true fitness.
And then you'll notice the diet and exercise showed both an increase in fitness due to the exercise as well as the weight
loss effect. Why is fitness important? This is a study by Steve Blair in which he looked at mortality.
How many people out of a hundred survived. If they were unfit at the beginning and remained unfit,
about 12-14, I take that back, about 25% of the population did not survive through 16 years. Whereas, those who changed their
habits, started doing exercise and became fit had half the mortality over this 16-year follow up.
So exercise is important even if it doesn't change your weight. Let's change this a little bit, though.
We've talked about some big weight changes. 20 pounds. Well, let's talk a little bit
about how we gain weight. Do we gain that suddenly or not? As a population we really don't. This is a redrawing of the
weight data for the US population from 1962 through 2004. And on average, there's been an
increase among the women and among the men of about 23 pounds over this 45-year period. That's all of three-fourths of a
pound per year on average. Not much. In fact, that's been my problem through my life.
Each year a pound heavier, right? If you calculate how many calories lead to that
three-quarter pound gain, it's only about 2,450 calories. It's about three Big Macs. Or about an average of seven
calories per day. A Life Saver contains six calories. So, despite this weight gain,
the body has done pretty well at controlling energy balance, but it has a little error on the positive side.
And do remember, of course, that all this time that these adults are gaining that 23 pounds, their energy expenditure is
going up because they're larger, they have to keep a bigger body functioning, and they have to move a bigger body when they
walk and move across the room or to the car or to shopping. So there are actually two energy gaps that we can talk about when
we talk about weight gain. One is this little bit of positive energy gap averaged across 365 days a year for a
seven-tenths of a pound weight gain, or seven-tenths of a kilo, little over a pound weight gain. That little gap is being
maintained on average in our population so that we're constantly gaining weight for year to year to year.
But as we're getting larger as a population, do remember maintenance energy has increased.
So there are two gaps, actually. There's about a 240K cal per day gap in the amount of energy that you have to consume to not fall
back to this weight but to maintain this higher weight, and then that little tiny gap to gain a little bit of weight each
year. If we're talking about moving not from a healthy weight, average healthy weight between
men and women of 140 pounds but to an obese weight of almost 200 pounds, we need a little bit bigger gap each day, on average
now twice as big, 14 calories, and the maintenance energy gap is almost 500 calories. But, again, for this slow weight
creep, we're only talking about a little bit of an error averaged out per day. Now, fortunately, we don't gain
weight a little bit each day. We fluctuate. Anyone who's gotten on the scale knows that it fluctuates a
couple to three pounds from day to day depending on what you eat and how much you're fully hydrated or not.
But this was a fascinating study in which they measured actually employees at the National Institute of Health every three
months through the year. During the period from mid-September to November, they gained .2 kilos on average.
Again, there's a range out there. Some of them gained 5 pounds, 10 pounds, some of them
lost 5 pounds. But then from this period from mid-November to January, they gained .4-kilos.
What happens between November and January? We've got the holidays. We've got Thanksgiving.
We've got Christmas, Hanukkah. We've got Super Bowl. This was back before Super Bowl was in February.
All of these things where we're eating more frequently and where we're surrounded by even more food.
And then afterward, unfortunately what didn't happen is they didn't lose this. They hung on to it.
They didn't fall back. So that this holiday weight gain accounted for about two-thirds of that annual little creep of
about a pound a year. This means, though, that here they're overeating an average about 13 calories per day not 7.
It's a little bigger number. Well, what if we break it down even further? This is a study in which
Susan Racette measured or had people weigh themselves at home every day, week in, week out, week in, week out,
for about three months. And then she averaged that data across. So Friday morning, we'll call
that zero. Saturday morning, after Friday night, they've gained not a lot. 50 grams?
Two ounces? Across Saturday, another 50 grams, another two ounces. Across Sunday, another 50 grams,
another two ounces. Now we're up to six ounces, a third of a pound. And then the control system
starts to regulate, starts to kick in. Monday they lose a little bit, Tuesday they lose a little bit
more, Wednesday a little bit more, but the problem here, and I think what the problem is with holidays, is that before you
fall back you start overeating again because you've got another Christmas party, you've got another holiday party, you've
got another Super Bowl party coming up. And that's my theory of what the problem is.
So, yeah, it's simply a matter of energy balance. You have to balance your resting metabolic rate, thermic effect
of meals, activity energy expenditure, your total energy expenditure against the calories that you eat as carbohydrates,
fat and protein. So we say eat less and exercise more. Simple.
How's that working for you? [LAUGHTER] Anybody find it so simple? Yes?
One question. [INAUDIBLE]
The question is some people find that after exercise. they actually lose their appetite. They don't eat more.
And in fact, the data does say that when you exercise and warm up your core body temperature, you do get a temporary reduction
in appetite but that goes away. And then most people, maybe that first meal they'll eat a little bit less but by 24 hours later,
they'll have eaten a little bit more. Okay, yes it's a simple equation, but if I ask you to
keep track of how many calories you eat and how many calories you expend, this is typical data that you'll see.
These were about a thousand individuals in Germany who were asked to report how many calories they eat and what
exercise they do, what activities they do during the day. And they calculated energy
expenditure, energy intake, and here the difference, energy intake minus energy expenditure. And you'll notice, on average,
the people down here at healthy weight are reporting that they eat 2,000 calories more than they expend every day.
Well, of course, they should be gaining weight. A lot of weight. And the obese individuals are
reporting that they eat 500 to 1500 calories less than they expend per day. So, of course, their obesity
should be going away. Well, it doesn't. This is the problem of survey techniques.
People underestimate what they eat, almost everyone, and overestimate their activity. The best way to measure your
energy balance is keep track of your weight. Every week, week in, week out, across the year.
It's a far more sensitive tool than trying to measure energy intake or expenditure. So that's lesson one from my
talk. But we still have the obesity problem. We still have this going on.
What evidence do we have of what might be the problem? Well, we don't know exactly what it is but there is something
that's coming back. This is fascinating study out of Harvard in which over a number of four-year periods they ask
people what they ate, okay the calories were off but they could look at what foods were being reported, and they looked at a
four-year weight change. And then they averaged this across a lot of different foods. And the foods that they found to
be problems, those associated with a weight gain of about one and a half to two pounds per year, or that's four years, so
about a half a pound per year. Things like potato chips. They're high in fat, high in calories.
They're also snack foods. Potatoes or fries, and it's actually fries, it wasn't so much other forms of potatoes.
Processed meats, red meats and then things that didn't have much of an affect either way, butter, sweets or desserts,
refined grains. The things that were a little protective, vegetables, nuts, whole grains containing fiber,
fruits, and another dairy food, yogurt. These, surprisingly, are all the things that we, as
nutritionists, call a healthy diet. Low in processed foods, low in snack foods, high in fruits and
vegetables and whole grains. High in fiber. Among the beverages, sugar sweetened beverages are
associated with a small weight gain. Sugared fruit juices, even 100% fruit juices are the same.
Dairy, fairly neutral. Zero calorie diet sodas, pretty much neutral. What's this?
[LAUGHTER] These are the points of lights. This is a point of light for every McDonald's
in the United States. That's another thing that's changed dramatically in the last 45 years.
The further distance between any two McDonald's in the US is only 145 miles. If you're in a city, you're
within 10 minutes. Now, if you add to this Wendy's, just add them up, Popeye's, Kentucky Fried Chicken, all of
these fast food places means you're minutes away from fast food, food that you can get at any time.
It tastes good so it encourages us to eat. And, in fact, to make it worse, look what's happened to portion
sizes here in the last 35 years. Two slices of pizza at an average restaurant used to be about 500 calories.
They're not 850 calories. Cheeseburger, 330, in fact even the old McDonald's that I used to get for 15 cents in 1966 when
I was in high school would have been even a little bit smaller than this. Now, your cheeseburger,
double burger, Quarter Pounder, almost 600 calories. And you can get hamburgers that are 1500 calories if you want.
Cup of coffee, coffee with a little milk and sugar used to be 45 calories. Now you go get your double
latte, 330 calories. Bagels, bagel used to be pretty small little piece of bread, 140 calories.
Now it's a handful. 350 calories. So not only is food easily available from almost any store
or any fast food restaurant, but what you're served is larger. Now, we can't totally blame fast food because you have a choice.
You can order a meal, Quarter Pounder with cheese, large fries, medium shake, 1600 calories with 55 grams of
saturated fat. Or you can order the McChicken with a side salad, southwest salad, little dressing,
two apple slices, 655 calories. This is about your caloric requirement. This is over half your caloric
requirement. So you do have a choice, but unfortunately many people order this one.
And in fact, a little aside, in New York City when they passed the law that you had to label menus, what happened is that
people at McDonald's, largely young males, 20 to 35 years of age, tended to order more and more calories because they
wanted more for their dollar. The only place that the menu labeling showed a change in behavior were in the beverage
shops, the coffee shops. There people started ordering fewer calories. So, here's the problem, or a
picture of it. It's not a terrible problem. This is a picture of a week's worth of food, average food, in
a US family. What do you see? Okay, high calorie pizza. Okay, my eyes are getting bad.
Snack foods. Little bit of a red meat. Little bit of fruit. Processed food.
Low in fiber. Other sugar drinks up here. We do see milk. Not the ideal diet.
Not the ideal healthy diet. Compare that to China. First of all, you'll notice there's about half the food
there. Also a family of four. They are shorter so their energy requirement is smaller because
they're smaller people. You see more fruit and vegetables. You do see meats, but you don't
see much in the way of pre-prepared foods. You don't see much in the way of snacks.
These are snacks but there are not a lot of them. Fresh bread. Some drinks.
Eggs. Meat. Again, a lot more prepared food. Now I'll also point out it's not
the perfect answer. The wife here, she is overweight, possibly obese. And actually if we go back,
no one in this picture would be classified as obese. So it's not a yes or no simple answer, but it is a big part of
the problem. So thank you. [APPLAUSE]