Syndrome X: Prescribing the Right Carbohydrates
by Connie Guttersen, RD PhD,
author of the Sonoma Diet
Syndrome X,
a condition referenced by Gerald Reaven, establishes a link
between obesity, insulin resistance, and heart disease. The
link is based on a metabolic collection of symptoms, which
are interdependent upon the development of these diseases.
Syndrome X:
Characteristic Metabolic Symptoms
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- Insulin
Resistance
- Abdominal
Obesity
- Decreased
High Density Lipoprotein
- Increased
Blood Triglycerides
- Smaller,
Denser Low Density Lipoproteins
- Increased
Apo B proteins
- Hypertension
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The five-year Quebec
Cardiovascular study concluded that men with Syndrome X symptoms
had a much higher incidence of heart disease than men who
had other classic heart disease risk factors. Insulin resistance
and hyperinsulinemia are major health problems. Twenty-five
percent of adults are insulin resistant to some degree, despite
normal blood glucose levels. The blood glucose levels are
maintained in normal range as a result of the pancreas working
overtime to secrete larger amounts of insulin. This can compensate
for some time, however, elevated insulin levels over time
can damage the arteries as well as promote adverse lipid profiles,
both of these are known risk factors for developing heart
disease. Once the pancreas begins to exhaust, blood glucose
begins to climb. This condition, impaired fasting glucose,
also contributes to developing diabetes and heart disease.
 Syndrome
X and insulin resistance are most common in adults who carry
their excess body fat as a spare tire or around the waist
and upper body. This type of body fat distribution, also referred
to as the apple, in contrast to the pear or lower body fat
deposits, is a know risk factor for coronary heart disease
and diabetes. The abdominal fat deposits which carry the most
risk are those which are situated deep inside and around the
organs (visceral) as compared to the fat deposits just under
the skin (subcutaneous). Visceral fat cells have different
characteristics than subcutaneous fat cells. They are more
metabolically active and promote elevated blood glucose and
triglyceride levels, as well as insulin resistance.
The promising news – visceral abdominal fat is most responsive
to vigorous exercise and a healthy diet. With this decrease
in abdominal fat comes a disappearance of insulin resistance
and Syndrome X. Exercise is the drug of choice for bringing
down elevated insulin levels.
Syndrome X’s nationwide attention is going beyond the
scientific community, especially since it affects one in 4
Americans and may play a role in half of all heart attacks.
This growing interest among consumers has also given popular
rise to a group of diets, which blame carbohydrates and insulin
for American’s obesity epidemic and high rate of heart
disease. The best sellers include Sugar Busters, The
Zone, Protein Power and Dr.
Atkins New Diet Revolution. The enticing pitches include,
"lose the sugar, keep the steak, eggs, and cheese",
"fat does not make you fat, carbohydrates do", and
"basta with the Pasta". According
to these books, we should stop counting calories and fat
grams, reduce all types of carbohydrates, in some cases to
exaggerated minimal levels, and increase dietary intake of
animal proteins. As a result, many Americans are carbophobic
and will try their best to avoid pasta, bread, fruits and
vegetables. This has also created many misconceptions of ketosis.
Unfortunately, the general idea is that ketosis is a good
condition which promotes weight loss, energetic feeling or
euphoric feeling, while greatly minimizing the risks. From
a nutritional perspective, these plans do little to emphasize
the different types of carbohydrates, especially within the
complex carbohydrate section: fibrous, non-refined vs. starchy,
non-fibrous carbohydrates. Plus, there is minimal discussion
on the difference between the different types of dietary fat
and proteins (animal vs. plant) and of the potential deficiency
of protective nutrients such as antioxidants, phytochemicals,
and fiber.
 These
plans often result in a decreased intake of fruits, vegetables,
beans, legumes, and whole grains. Another risk is the potential
increase for saturated fat consumption, a well-known risk
factor for heart disease. These diets are quite popular; especially
since short-term weight loss does occur. However, much of
this is due to water loss, resulting from the lower carbohydrate
and calorie intakes.
Testing
the Hypothesis: Are Low Carbohydrate Diets Healthy?
Why
are the low carbohydrate-high protein diets so popular? Partly
because Americans have been on a low fat-high carbohydrate
frenzy for 30 years – and with no success. This notion
of "healthy fat free" has contributed to heavier
Americans, higher caloric intakes, and greater amounts of
sugar intake (150 pounds per year per individual). Many food
manufacturers have used sweetened refined grains as an important
source of fat free products. Their popularity among Americans
has made this way of eating very accessible.
For
many Americans, who have been losing the battle
of the bulge, these low-carbohydrate-high protein
diets offer a different approach and allow for
foods that aren’t typically found on the
low fat diet. These include bacon, sausage, cheese,
and other high fat proteins.
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The
hypothesis of these low carbohydrate diets contends that high
carbohydrate intakes result in increased fat storage through
transient insulin surges and also from insulin resistance.
They also conclude that insulin resistance is responsible
for obesity and heart disease. Current medical research indicates
a slightly different view. Higher insulin levels damage arteries
only when these levels are excessive when compared to the
blood glucose level requirements. For most carbohydrate foods,
even those with a higher glycemic index, the amount of insulin
produced actually matches the rise in blood glucose. This
is a normal situation that allows the transport of glucose
into the cells. And while insulin resistance is thought to
be a culprit in heart disease and obesity, it’s the expanding
waistlines and a lack of physical activity that makes insulin
resistance worse. However, once insulin resistance develops
it is more difficult to lose weight.
A
ten-year follow-up study of 75,521 women suggests that
a high dietary glycemic load from refined carbohydrates increases
the risk of coronary heart disease, independent of known coronary
disease risk factors. Women who consumed the largest amounts
of refined starchy carbohydrates: potatoes, white rice, white
bread, and sugar had an 85% greater risk of heart attack.
Glycemic index was a stronger predictor of coronary heart
disease than the usual classification of complex vs. simple
carbohydrates. High glycemic loads do not appear to affect
coronary heart disease risk among women with low BMI (<23).
This may explain why some populations, such as those in rural
China, have lower rates of coronary heart disease, despite
a high carbohydrate intake. Traditionally, these populations
have a lower prevalence of obesity, are more physically active,
and consume carbohydrates in a less refined form.
A large intake of high glycemic carbohydrates also increases
the risk of diabetes.
In the Harvard School of Public Health: Nurses Health Study,
frequent surges of insulin due to high glycemic carbohydrates--soft
drinks, refined rice, pasta, and potatoes--increased the risk
of diabetes 2.5 times more than when compared to the lower
glycemic index carbohydrates with higher fiber intakes. This
study found no relation between total carbohydrate intake
and diabetes; the important factor was the type of carbohydrate
consumed. Whole grains, which contain fiber, were found to
have a protective effect.
Choosing
the Right Carbohydrates
The
results from these clinical studies must be addressed to the
American consumer carefully, since there is much confusion
about what is healthy and the best ways to lose weight. Solving
the mystery behind carbohydrates lies in consuming the best
type of carbohydrates, rather than simply focusing on the
total amount. A healthy balance of fibrous non-refined with
non-fibrous carbohydrates should comprise the category of
complex carbohydrates. Identifying these foods to consumers
is critical. Our typical American cuisine does not offer many
venues. However traditional ethnic cuisines from the Mediterranean,
Asia, and Latin America contain a vast collection of delicious
preparations for beans, whole grains, and legumes.
 While
these studies indicate that total amounts of carbohydrate
don’t appear to be as important as the type, it must
still be addressed on an individual basis. Carbohydrate levels
above 45 to 50% may exacerbate unfavorable insulin, glucose,
triglycerides, and high density lipoprotein levels in individuals
who are already overweight,
sedentary, and insulin resistant. Thus, a diet for these individuals
should reflect slightly lower intakes of carbohydrate, 42-45%
of total calories, and emphasize the non refined, fibrous
types. A moderate fat intake of 35 to 40% is also recommended,
as long as the majority is monounsaturated. An emphasis on
monounsaturated is important since higher intakes of saturated
fat have been found to promote insulin resistance by altering
cell membrane characteristics. Exercise and weight loss are
also an important part of the equation. The body’s response
to insulin and glucose improves with consistent weight loss
and regular physical activity. Once regular exercise and weight
loss have been established, a higher carbohydrate intake,
up to 50% of total caloric intake, can be tolerated as long
as the carbohydrate comes largely from unrefined fibrous sources.
A realistic view of these many diets is to realize that any
diet, which restricts total caloric intake, will result in
weight loss. However, it is the quality of the foods consumed
that will impact long term health. It is our professional
responsibility to address this but to also provide the link
between science and food. See our ideas for healthy and easy
recipes for consumers
and foodservice.
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