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Thirty years ago, when Nathan Pritikin opened the Pritikin Longevity
Center® to help people improve cholesterol levels and prevent
heart attacks, he noticed that many people at the Center were struggling
not just with high cholesterol but also with hypertension and high
blood sugar. Several had full-blown diabetes. Most
were also overweight.
The good news, Nathan observed, was that his diet-and-exercise
program seemed to help all these problems. But Nathan, ever
curious about the workings of the human body, was perplexed. Why,
he wondered, did all these things seem to go hand-in-hand? Could
they be linked in some way?
Today, scientists have answers to Nathan’s observations. There
is a link, and it’s called the Metabolic Syndrome.
What is the Metabolic Syndrome?
The Metabolic Syndrome, also known as Syndrome X, is not a disease,
per se. Rather, it is a cluster of factors (see below) that
are an important warning sign because the syndrome can lead to
diabetes as well as heart disease. In the next decade, predicts
Dr. David Heber, Director of UCLA’s Center for Human Nutrition,
roughly 80% of all heart disease will be due to the Metabolic Syndrome
and type 2 diabetes. Even if blood sugar levels never go
high enough to be classified as diabetes, the Metabolic Syndrome
still promotes heart disease.
According to guidelines established by the National Cholesterol
Education Program, you probably have the Metabolic Syndrome if
you have three or more of the following five risk factors:
- Abdominal obesity: a waist of 40 inches or more for men,
35 inches or more for women
- High triglycerides: 150 mg/dL or more
- Low HDL (“good”) cholesterol: below 40 mg/dL
for men, below 50 for women. Most people with the syndrome
also have more small, dense LDL (“very bad”) cholesterol
particles*
- High blood pressure: 130/85 or higher (or if you are
taking hypertension medication)
- Elevated fasting blood sugar (glucose): 110 mg/dL** or
more
* These small, dense LDLs are usually not measured with standard
blood lipid profiles. To monitor them, the physicians at
the Pritikin Center order specialized blood tests.
** A few months ago, the American Diabetes Association lowered
the cut point for elevated fasting glucose to 100 mg/dL, so the
Pritikin Center uses 100 – not 110 – to denote elevated
glucose.
If you have the Metabolic Syndrome, you’re far from alone. According
to new government figures, more than 64 million Americans have
it, roughly one in four adults and 40% of adults age 40 and older,
an increase of 60% over the last decade.
Alarmingly, growing numbers of kids are now being diagnosed with
the syndrome. Newly published research from Yale University
found that the fatter the child, the more likely he or she is to
have the syndrome, and those who are severely obese have a 50%
chance of having it.(1)
What causes the Metabolic Syndrome?
The Metabolic Syndrome usually begins with insulin resistance. Insulin
resistance happens when our cells “resist” insulin. Normally,
our body changes the sugars and starches we eat into a form of
sugar called glucose. The bloodstream carries the glucose
to the body’s cells. Insulin, a hormone produced by
the pancreas, “ushers” glucose into our cells, where
it’s converted to energy. You are insulin resistant
if your cells don’t want to “accept” the insulin. Figuratively-speaking,
your cells have signs on their doors that say, “Sorry, closed
for business. We already have all the glucose we need.” So
the pancreas has to pump out more insulin in an effort to “push” those
doors open and keep blood sugar levels from going too high.
In about half of all cases, insulin resistance leads to ever-rising
blood sugar levels and type 2 diabetes (defined as fasting glucose
of 126 mg/dL or more). That’s why insulin resistance
is often called a “pre-diabetic” condition. Ultimately,
the pancreas may give out. For years, it’s been on
overdrive, pumping out more and more insulin, trying to break through
the cells’ doors. Eventually, it cannot produce enough
extra insulin to overcome the insulin resistance. That’s
why people who’ve had type 2 diabetes for many years must
often resort to insulin shots.
What causes insulin resistance?
Here’s what we know. Environment plays a key role: the
great majority of people with insulin resistance are overweight. But
scientists know genetic susceptibility plays a role as well because
some normal-weight people are insulin resistant – and some
very obese people are not.
Four other factors contribute to insulin resistance: poor
diet, inactivity, smoking, and aging. Even in normal-weight
people, a diet high in fats and refined sugars is associated with
greater risk of developing insulin resistance and all other aspects
of the Metabolic Syndrome.
How do you prevent or control the Metabolic Syndrome?
There is no one magic pill that erases the syndrome. Pharmaceutically,
it is treated in piecemeal fashion. People take one type
of drug, usually statins, to control cholesterol, another to lower
blood pressure, another to lower triglycerides, and still others
to treat high blood sugar. To date, no drugs have been approved
for insulin resistance.
The far better approach – one that treats the overall problem – is
the more natural way: a healthy diet and regular exercise. It
is also the most effective way, argue experts like UCLA’s
Dr. Heber and Dr. Paul Ridker of the Center for Cardiovascular
Disease Prevention at Brigham and Women’s Hospital in Boston,
because it targets what are often the roots of the problem: poor
diet and excess body fat, especially in the belly.
Oh, what that spare tire can do
Excess abdominal fat is so problematic, scientists are now finding,
because it is not just a dormant roll of flab. Those fat
cells, wrapped around organs like the liver and pancreas, are very
active. They pump out chemicals, like cytokines, that raise
blood pressure, worsen cholesterol levels, and foul up the delicate
system by which insulin works, causing insulin resistance. They
also trigger inflammation throughout the body. That’s
bad news because high levels of inflammation mean high levels of
C-reactive protein (CPR), which are increasingly linked with higher
risk of heart attacks, strokes, osteoarthritis, and even Alzheimer’s
disease.
Cleaning up
But when you start to lose body fat with lifestyle-change programs
like Pritikin, all these problems fade – quickly
and simultaneously. Since 1980, studies published in peer-reviewed
journals like Diabetes Care and the New England Journal
of Medicine have shown that the Pritikin Program lowers blood
pressure, dramatically improves cholesterol and triglyceride profiles,
sheds body fat, and normalizes blood sugar levels.
The good news, too, is that just a small amount of weight loss – about
5% of body weight – can help restore insulin sensitivity. In
fact, just getting started on the Pritikin Program nets
huge benefits. In only three weeks, UCLA researchers found,
the Pritikin Program controlled the Metabolic Syndrome in a majority
of 72 people studied. Insulin levels dropped an average of
32%, and triglycerides fell 26%. Average weight
loss was 8.5 pounds; total cholesterol dropped 22%; and blood pressure
returned to normal levels.(2)
Newly published research also found that in just two weeks C-reactive
protein levels plummeted on average 45% in women at the Pritikin
Longevity Center.(3) No
other diet-and-exercise program or drug therapy, including statins,
has proven to lower C-reactive protein so dramatically or rapidly.
And just last month, doctors and dietitians at Pritikin analyzed
the data of 37 men and women, all with the Metabolic Syndrome,
who came to Pritikin for two weeks. They found that 50% graduated
from Pritikin free of the Metabolic Syndrome. They had improved
their profiles – cholesterol, blood pressure, triglycerides,
and blood sugars – so much that they no longer met the three-risk-factor
criteria for the syndrome.
“The results of this study suggest that dramatic changes
in diet and activity levels can quickly and favorably alter most
of the metabolic abnormalities seen in people with the Metabolic
Syndrome,” notes Dr. James Kenney, Nutrition Research Specialist
at the Pritikin Longevity Center.
Children benefit, too. In a just completed analysis of kids
attending the Pritikin Family Program last summer, UCLA scientists
found that all eight of the children who came to Pritikin with
the Metabolic Syndrome left Pritikin just two weeks later free
of the syndrome.
Low-carb diets
Some low-carb diet books claim that a high-carbohydrate diet causes
insulin resistance, and that in turn is what’s making us
fat. Such claims are bogus. “There’s no
evidence that carbohydrate-rich foods cause insulin resistance,” summarized
the Berkeley Wellness Letter in June 2003. “Moreover,
insulin resistance doesn’t make people fat. Most experts
believe that insulin resistance is largely a result of obesity,
lack of exercise, smoking, and aging.”
Key cause of obesity
People get fat because they take in more calories than they burn. Plain
and simple. A diet that is dense with calories and a lifestyle
with little or no calorie-burning physical activity promote excess
calorie intake, excess weight, insulin resistance, and associated
metabolic problems.
The optimal dietary approach
The vast majority of nutrition scientists agree that the best
way to control weight is to control calories, and the best way
to control calories – without going hungry – is to
eat foods that provide a lot of stomach-filling volume, but not
a lot of calories. This is a diet, in effect, that is full
of fiber- and water-rich foods like fruits, vegetables, beans,
and whole grains. The second requirement: daily exercise.
The evidence in support of fiber-rich, water-rich foods to control
weight is so strong that in its Report of the U.S. Dietary
Guidelines Advisory Committee on the Dietary Guidelines for Americans,
2005, the 13-member panel of experts from academia recommended
that overweight Americans choose foods that allow them to eat larger
portions for fewer calories – foods, in short, that have
a low calorie density, such as “raw vegetables or low-fat
soups.” The experts advised that Americans choose whole
grains over refined grains, and increase their intake of fruits
and vegetables to 5 to 13 servings daily.
Potatoes vs. croissants
In general, fat-rich foods and more processed and refined foods
are more calorie-dense than foods in their natural whole state. Calorie
for calorie, they also provide far less satisfaction, or satiety. Research
analyzing how full people felt after eating 100 calories of various
foods found that some of the least filling foods were
cakes, doughnuts, and cookies (all high in fat, sugar, and refined
carbs).(4) Per calorie,
it would take over six times the amount of calories from
croissants to achieve the same level of satiety as baked potatoes.
The more croissants and other calorie-dense foods you eat, the
more calories you are likely to ingest, and the greater your risk
of becoming insulin resistant. In animals genetically susceptible
to insulin resistance, research has shown that simply offering
them a diet high in fat and refined carbohydrate leads to overeating
and induction of insulin resistance within just a few days.(5)
And in large-scale population studies of men and women in the
U.S., Harvard researchers found that diets with more hydrogenated
and saturated fat were linked with the development of insulin resistance
and the Metabolic Syndrome. Conversely, diets higher in unrefined
carbohydrates appeared protective.(6, 7)
Diabetes prevention
Diets focusing on fiber-filled, unrefined carbohydrates have also
been proven to prevent diabetes. Results from two long-term
trials studying nearly 4,000 people with a pre-diabetic condition
called impaired glucose tolerance – the U.S. Diabetes Prevention
Program (8) and the Finnish Diabetes
Prevention Group (9) – found
that diets high in fruits, vegetables, beans, and whole grains
combined with exercise led to weight loss and about a 60% reduced
risk of developing diabetes.
And new research from Oregon Health & Science University found
that a low-fat, high-fiber diet caused significant weight loss
in type 2 diabetics, whereas a diet high in monounsaturated fats
did not.
For both diets, the subjects were encouraged to eat ad libitum,
that is, as much or as little as they wanted. This “real
world” approach, the scientists suspected, would create more
accurate results than previous studies, which had forced subjects
to eat as many calories on low-fat diets as they had on high-fat
diets. Unlike these earlier studies, the low-fat, ad libitum
diet in the Oregon study did not raise triglyceride levels
or worsen glycemic control. In fact, it improved both. The
authors concluded that “ad libitum low-fat, high-fiber diets
may be very useful in the dietary management of type 2 diabetes.” (10)
And recently, the U.S. Agriculture Research Service found that
eating more whole-grain foods eased the Metabolic Syndrome. The
scientists, from Tufts University in Boston, analyzed food consumption
data and medical tests from 2,834 men and women and concluded that
eating three or more servings of whole-grain foods like fiber-rich
cereals and brown rice each day improved insulin sensitivity and
lowered the risk of Metabolic Syndrome. Refined grains did
not protect against the syndrome.(11)
Bottom Line
The optimal approach for preventing the Metabolic Syndrome is
to lose excess weight with regular exercise and a diet, like the
Pritikin Eating Plan, that focuses on foods that are low in calorie
density and naturally high in fiber and nutrients, including whole-grain
foods like hot cereals, corn, whole-wheat pasta, and brown rice;
generous amounts of fruits, vegetables, and starchy foods like
potatoes, yams, beans, lentils, and peas; and modest amounts of
nonfat dairy products, seafood, and lean poultry and meat.
As more than 100 studies in top medical journals have proven,
and as Nathan Pritikin observed nearly 30 years ago, this simple
but powerful diet-and-exercise approach acts like a one-two punch
on the Metabolic Syndrome, and, in doing so, helps prevent and
control the leading causes of death and disability in the United
States, including cardiovascular disease, type 2 diabetes, hypertension,
and stroke.
“If ever there were a magic bullet for losing weight and building
long-term health, the Pritikin Program® is it,” sums up
Dr. Kenney.
(1) New England Journal of Medicine,
2004; 350: 2362.
(2) American Journal of Cardiology,
1992; 69: 440.
(3) Metabolism, 2004; 53: 377.
(4) European Journal of Clinical Nutrition,
1995; 49: 675.
(5) Diabetes, 2001; 50: 2786.
(6) American Journal of Clinical Nutrition,
2001; 73: 1019.
(7) Diabetes Care, 2002; 25: 417.
(8) New England Journal of Medicine,
2002; 346: 393.
(9) New England Journal of Medicine,
2001; 344: 1343.
(10) American Journal of Clinical
Nutrition, 2004; 80: 668.
(11) Diabetes Care, 2004; 27: 538.
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