The term metabolic syndrome may be new to many, but it has almost
certainly been around for thousands of years. It was only in 1988,
when it was named “Syndrome X” by Dr. Gerald Reaven, a professor of
medicine at Stanford University School of Medicine, that we really
began to hear about it and how lifestyle can work for or against
individual risk of developing this syndrome.
Metabolic syndrome
(also sometimes referred to as “insulin resistance syndrome”) is
diagnosed when a person has three or more of the following conditions:
abdominal obesity, high triglyceride levels, low high-density
lipoprote in (HDL) levels, high blood pressure, and high fasting blood
glucose levels. Together, the symptoms
of metabolic syndrome place a person at high risk of developing Type 2
diabetes and cardiovascular disease (1).
Who is
at risk?
Genetics:
According to Dr. Gerald Reaven, about 50% of a person’s degree of
insulin resistance can be attributed to genetics and 50% can be
attributed to lifestyle factors (1). A study conducted at the National
Taiwan University Hospital in Taipei, found that metabolic syndrome is
heritable in Chinese and Japanese hypertensive families (2).
Interestingly, there appears to be some differences in the way men and
women respond to heritable risk factors: a study conducted in 11
provinces in China found that the
most significant risk factors of metabolic syndrome in men were waist
circumference
and a family history of diabetes mellitus; in women, primary risk
factors were waist circumference and a family history of high blood
pressure (3).
Obesity:
Obesity, especially abdominal obesity, is fundamental to metabolic
syndrome. It is believed that free fatty acids and their metabolites
from abdominal fat, play a role in triggering insulin resistance (2).
Scientists still aren’tีt sure what gene gives
rise to metabolic syndrome, but believe there is a link with those genes
which predispose to obesity and overweight.
Physical inactivity:
Physical inactivity goes hand in hand with obesity, and is an
important risk factor for the development of metabolic syndrome.
Physical in-activity not only increases the risk of developing metabolic
syndrome, but further increases health risks associated with metabolic
syndrome because of its negative effect on cardiovascular fitness.
Age: A study in
the US has revealed that cases of metabolic syndrome increase
significantly with age, from 6.7% in 20 to 29 year olds, to about 43.5%
and 42.0% for those aged 60 to 69 years, respectively. The age adjusted
prevalence was similar for men (24.0%) and women (23.4%) (4).
Prevention and
Treatment
As weight gain and
sedentary lifestyles are both common factors in the development of
metabolic syndrome, the American Heart Association recommends that
treatment and prevention of metabolic syndrome should include achieving
ideal body weight and increasing physical activity. Both are also
time-tested methods of improving insulin sensitivity, blood pressure and
lipoprotein levels.
Weight
Reduction
Overweight and obesity
are always a direct result of calorie intake exceeding calorie output.
It follows therefore, that weight loss can only be achieved by creating
a calorie deficit. To achieve a calorie deficit, calorie intake from
food must be reduced and/or calorie output in the form of physical
activity must be increased. An obvious statement perhaps, but worth
repeating given the clear difficulty many have in controlling body
weight.
Diet
A moderately high
carbohydrate (45-55% of the daily calories), low fat diet (10-15% of
total daily calories) is the best option for weight loss and prevention
of weight gain. Choosing complex, starchy carbohydrate foods such as
wholegrain cereals and plenty of fruit and vegetables will help to keep
hunger pangs at bay and brings other health benefits such as reduced
bowel cancer risk. Similarly, limiting fat intake is a sensible option
to reduce daily calorie consumption (fat is the most energy dense food
type, but is less satiating than protein and carbohydrates), and
replacing saturated fats with unsaturated fats will help to reduced the
risk of cardiovascular disease, associated with metabolic
syndrome.
Gradual weight loss, and small sustainable changes to diet are keys to
long-term success in weight loss or prevention of weight gain. Finding
ways to make healthy eating enjoyable and as easy as possible are
essential ingredients in developing lifelong healthy lifestyle habits.
For example, learning to balance occasional energy-dense foods with
lower calorie, nutrient-dense foods, adjusting portion sizes and
enjoying occasional treats without feeling guilty can help to sustain
motivation to adopt a balanced diet for life.
Physical Activity
A study in Finland
found that men who exercised more than 3 hours per week decreased their
risk of developing metabolic syndrome by about 50%, compared with the
men who exercised no more than 60 minutes per week (5). Regular physical
activity has also been seen to reduce VLDL and LDL cholesterol, while
raising HDL cholesterol, lowering blood pressure, and reducing insulin
resistance (4).
Current guidelines
vary, but a reasonable goal, would seem to be at least 30 minutes per
day of exercise which uses some or all major muscle groups, and
increases heart and respiration rate significantly, but comfortably.
Some individuals may prefer to complete 30 minutes of activity in one
session, but two or three individual chunks lasting between 10 and 15
minutes each is also OK and may be more manageable for some people.
Taking the stairs instead of the elevator, taking 10-minute activity
breaks at work are examples of the varied ways in which activity can be
incorporated into a daily regime.
A Final Word...
Metabolic syndrome is
predicted to become a major public health problem in many developed, as
well as developing countries. Individual and community-wide efforts to
change health behaviours are vital. Given the importance of establishing
lifelong healthy lifestyle habits, and the emerging evidence that
metabolic syndrome is at least partly hereditary, it is never too early
for not only adults, but children too, to adopt healthy lifestyles
habits.
The Diagnosis
Metabolic syndrome can
be diagnosed if an individual has any three of the following
conditions:
·
Central fat distribution: A waist
circumference greater than 40 inches (102 cm) in men and 35 inches (88
cm) in women. (Abdominal obesity appears to more highly correlated with
the metabolic risk factors than measures of total body weight such as
Body Mass Index (BMI)
·
Raised blood pressure: Pressure at or
above 135 / 85 mm Hg.
·
Serum triglyceride levels at or above 150
mg/dl (1.7 mmol/L).
·
“Good” cholesterol (HDL) levels at or
below 40 mg/dl (1.04 mmol/L) in men and at or below 50 mg/dl (1.29 mmol/L)
in women.
·
Fasting blood glucose levels at or above
110 mg/dl (6.1 mmol/L).
