The term "overweight" refers to increased body weight in relation to
height, when compared to some standard
of acceptable or desirable
weight.
NOTE: Overweight may or may not be due to increases in body fat.
It may also be due to an increase in lean muscle.
For example, professional athletes may be very lean and muscular, with
very little body fat, yet they may weigh more
than others of the same
height.
While they may qualify as "overweight" due to their large muscle mass,
they are not necessarily "over fat,"
regardless of BMI (body mass index)
Obesity (definition):
Obesity is defined as an excessively high amount of body fat or adipose
tissue in relation to lean body mass.
The amount of body fat (or adiposity) includes concern for both the
distribution of fat throughout the body
and the size of the adipose
tissue deposits.
Body fat distribution can be estimated by skinfold measures,
waist-to-hip circumference ratios, or techniques
such as ultrasound,
computed tomography, or magnetic resonance imaging.
Causes:
Energy imbalance (when the number of calories
consumed is not equal to the number of calories used).
Overweight and obesity result from an energy imbalance maintained over
a long period of time.
This involves eating too many calories and not getting enough physical
activity.
Body weight is the result of genes, metabolism, behavior, environment,
culture, and socioeconomic status.
The cause of energy imbalance for each individual may be due to a
combination of these factors.
Genetics
Science shows that genetics plays a role in obesity.
Genes can directly cause obesity in disorders such as Bardet-Biedl
syndrome and Prader-Willi syndrome.
However genes do not always predict future health.
Genes and behavior may both be needed for a person to be overweight.
In some cases multiple genes may increase one’s susceptibility for
obesity and require outside factors;
such as abundant food supply or
little physical activity.
Genetics and the environment may increase the risk of personal weight
gain.
However, the choices a person makes in eating and physical activity
also contributes to overweight and obesity.
Behavior can increase a
person’s risk for gaining weight.
Looking back at the energy balance scale, weight gain is a result of
extra calorie consumption,
decreasing calories used (physical activity)
or both.
Personal choices concerning calorie consumption and physical activity
can lead to energy imbalance.
Diseases and Drugs
Some illnesses may lead to obesity or weight gain.
These may include Cushing's disease, and polycystic ovary syndrome.
Drugs such as steroids and some antidepressants may also cause weight
gain.
Body Mass Index (BMI)
Individuals with a BMI of 25 to 29.9 are considered overweight, while
individuals with a BMI of 30 or more
are considered obese.
Body Mass Index or BMI is a tool for indicating weight status in
adults. It is a measure of weight for height.
For adults over 20 years old, BMI falls into one of these categories:
| BMI |
Weight
Status |
Below 18.5
|
Underweight |
| 18.5 – 24.9 |
Normal |
25.0 – 29.9
|
Overweight |
| 30.0 and Above |
Obese |
BMI correlates with body fat.
The relation between fatness and BMI differs with age and gender.
For example, women are more likely to have a higher percent of body fat
than men for the same BMI.
On average, older people may have more body fat than younger adults
with the same BMI.
Calculating BMI
Using pounds and inches:
| BMI = ( |
Weight in
Pounds
|
) x 703 |
| (Height
in inches) x (Height in inches) |
For example, a person who weighs 220 pounds and is 6 feet 3 inches tall
has a BMI of 27.5.
| BMI = ( |
220 lbs.
|
) x 703 = 27.5 |
| (75
inches) x (75 inches) |
Using kilograms and meters:
| BMI = ( |
Weight in Kilograms
|
)
|
| (Height
in Meters) x (Height in Meters) |
For example, a person who weighs 99.79 Kilograms and is 1.905 Meters
(190.50 centimeters) tall has a BMI of 27.5.
| BMI = ( |
99.79 Kg
|
) = 27.5 |
| (1.905 m)
x (1.905 m) |
How does BMI relate to health?
The BMI ranges are based on the effect body weight has on disease and
death.
As BMI increases, the risk for some disease increases.
Some common conditions related to overweight and obesity include
· Premature death
· Cardiovascular disease
· High blood pressure
· Osteoarthritis
· Some cancers
· Diabetes
BMI is just one of many factors related to developing a chronic disease
(such as heart disease, cancer, or diabetes).
Other factors that may be important to look at when assessing your risk
for chronic disease include:
· Diet
· Physical Activity
· Waist Circumference
· Blood Pressure
· Blood Sugar Level
· Cholesterol Level
· Family History of disease
Recomendations:
All persons who are obese or overweight should try not to gain
additional weight.
In addition, those who are obese or who are overweight with other risk
factors should consider losing weight.
A complete health assessment by a physician is the best way to decide
the right steps for you.
Even a small weight loss (just 10% of your current weight) may help to
lower the risk of disease.
Physical activity and good nutrition are key factors in leading a
healthy lifestyle and reducing risk for disease.
A variety of healthy foods in the correct portion
sizes is helpful for achieving and maintaining a healthy weight.
Decrease calorie consumption: pre-packaged foods,
fast food restaurants, and soft drinks are fast and convenient
they
also tend to be high in fat, sugar, and calories.
Choosing many foods from these areas may contribute to an excessive
calorie intake.
Some foods are marketed as healthy, low fat, or fat-free, but may
contain more calories than the fat containing food,
they are designed to
replace.
It is important to read food labels for nutritional information and to
eat in moderation.
Larger portion size during a meal or snack can results in increased
calorie consumption.
If the body does not burn off the extra calories consumed from larger
portions, fast food, or soft drinks,
weight gain can occur.
Our bodies need calories for daily functions such as breathing,
digestion, and daily activities.
Weight gain occurs when calories consumed exceed this need.
Physical activity plays a key role in energy balance because it
uses up calories consumed.
Increase physical activity (any bodily movement produced by
skeletal muscles that results in an expenditure of energy)
and leisure
time activities:
Walking, skating, biking, swimming, playing Frisbee, dancing Structured
sports or exercise Softball,
tennis, football, aerobics
Regular physical activity is good for overall health.
Physical activity decreases the risk for colon cancer, diabetes, and
high blood pressure.
It also helps to control weight, contributes to healthy bones, muscles,
and joints; reduces falls among the elderly;
and helps to relieve the
pain of arthritis.
Physical activity does not have to be strenuous to be beneficial.
Moderate physical activity, such as 30 minutes of brisk walking five or
more times a week, also has health benefits.
According to the Behavioral Risk Factor Surveillance System, in 2000
more than 26% of adults reported no leisure time
physical activity.
Moderate-intensity activities such as household chores, gardening, and
walking can also provide health benefits.
Confidence in one’s ability to be active will help people make choices
to adopt a physically active lifestyle.
· Reduce time spent watching television
and in other sedentary behaviors
· Build physical activity into regular
routines
· Increases daily and leisure time
physical activity
· Increases calories used
· Decreases excessive calorie consumption
· Increases daily physical activity
· including at least 5 servings of
fruits and vegetables a day, and reasonable portion sizes
· Increases leisure time physical activity
A health professional is the best source to tell you whether illnesses,
medications, or psychological factors
are contributing to weight gain
or making weight loss hard.
