A Brief Overview of Obesity
Obesity is defined as having too much body fat – beyond simply being overweight. Too much fat, particularly around the waist where many vital organs are, increases the risk of high blood pressure, high cholesterol, heart disease, diabetes and stroke.
Obesity is such a public health concern that it is officially recognized as a major risk factor for
coronary heart disease. If left untreated, obesity can result in heart attack and stroke. The decision to include obesity in the risk factors for heart disease is based on scientific evidence that shows a relationship between obesity and:
- Lower levels of the ‘good cholesterol’ HDL – or high density lipoprotein– which help
protect against heart disease
- Higher levels of ‘bad cholesterol’ LDL – or low density lipoprotein and triglycerides–
which increase the risk for clogged arteries
- High blood pressure
- Diabetes, which can, in some people, dramatically increase the risk of heart attack.
What causes obesity?
The main cause of obesity is consuming more calories than you use, on a regular basis. Certain foods also contribute – foods containing saturated fat, trans fats and cholesterol are not only fattening, but will also increase your blood cholesterol levels. Check out our article on foods that you should never eat for more information.
If you lead an inactive lifestyle — say your job requires you to sit for most of the day and you don’t exercise regularly — your body won’t have the opportunity to use all the calories taken in during the day.
There are also risk factors such as:
- Genetics: Your genes can affect the amount of fat your body stores and how that fat is
distributed. Family history may also play a role here — if either of your parents is obese,
you may be at a higher risk for obesity
- Smoking: In addition to being a well-known risk factor for heart disease, cigarette smoking also increases the risk for obesity. Smokers often lead less physically active lifestyles. For smokers who quit, there are additional risks because there is a tendency to eat more, which can cause weight gain. And your sense of smell and taste improve, so certain foods may hold more appeal, causing you to eat more.
- Alcohol consumption: Alcohol is full of calories in the form of sugar. And, drinking a lot can stimulate your appetite and make you less concerned about portion size
- Age: The rate at which we burn calories — also known as our metabolic rate decreases with age. Additionally, our muscle mass decreases as we get older, and we tend to be less physically active. All these things mean that our bodies need fewer calories. But if we don’t cut back on our calorie intake accordingly, we can gain weight
- Pregnancy: Weight gain is expected during pregnancy and is necessary. But some women have difficulty losing the extra pounds after giving birth. This can lead to obesity
- Medical problems: Although a less common cause of obesity, hormonal imbalances such as polycystic ovary syndrome, thyroid function and Cushing’s syndrome can lead to obesity. Another obesity contributor is chronic arthritis, which impacts a person’s ability to be physically active
- Medications: Tricyclic antidepressants, antipsychotics, corticosteroids and some blood pressure medications are known to cause weight gain
What health conditions can obesity lead to?
Other diseases and conditions that can stem from obesity include:
- Metabolic syndrome
- Diabetes – typically type 2 diabetes
- Heart disease
- Kidney disease
- Liver problems
- Degenerative joint disease
- Breathing difficulties
- Menstrual problems
- Sleep apnea
Also check out our recent post with a more comprehensive list of health risks associated with obesity.
What is metabolic syndrome?
- Also called Syndrome X, metabolic syndrome refers to a group of risk factors known to cause heart disease. To be diagnosed with metabolic syndrome, you must have three of the following:
- High blood pressure (resting systolic/diastolic rates of 130/85 mm Hg or more)
- High blood sugar (fasting blood sugar of 110 mg/dL or more)
- High triglyceride levels (150 mg/dL or more)
- Below-normal levels of high density lipoprotein (HDL cholesterol) levels. In women, this translates to levels of less than 50 mg/dL, and in men, levels of less than 40 mg/dL
- A waist circumference of 40 inches (102 centimeters) or more for men, and 35 inches (88 centimetres) or more for women, which indicates being overweight or obese It is important to note that your risk for heart disease and stroke increases with the number of risk factors you have.
How is obesity diagnosed in adults?
A diagnosis of obesity will include a number of factors. Your healthcare professional will do a physical exam and possibly check for psychological problems that could be contributing factors.
Your medical history will also be taken into consideration, including any history of dieting and whether anyone in your family is obese or has diabetes or heart disease.
Your doctor will likely also want to know about your lifestyle: Do you exercise? How much? Do you smoke? What does your job entail? What kind of a social life do you lead: — do you drink much alcohol, for example.
The following will also be key factors in a diagnosis:
- Blood pressure
- Body Mass Index (BMI)
- Waist circumference: Measurements of 40 inches (102 centimeters) or more in men and
35 inches (88 centimeters) in women or more are associated with health risks
- Bioelectrical impedance analysis: This enables your doctor to more accurately determine the amounts of lean tissue and body fat
How is body fat measured?
Body fat is determined using waist circumference measurements and BMI. The formula for calculating BMI uses your body weight relative to your height. To find out your BMI, check out our online BMI calculator.
This may change over the next few years, so that body mass calculations take into account muscle mass; some people are heavier because they have a greater muscle mass.
There are two formulas for calculating your BMI:
1. Your weight (in kilograms – 2.2 pounds per kilogram) divided by the square of your height in meters (39.37 inches per meter).
2. Multiply weight in pounds by 703. Then divide that total by height in inches. Then divide that last total by height in inches.
According to studies done by the National Center for Health Statistics in the United States:
- A BMI of 18.5 or less is considered underweight
- A BMI in the range of 18.5 to 24.9 is considered normal
- BMI values between 25.0 and 29.0 indicate being overweight – with a BMI of 25 kg/m2
generally indicating being overweight by approximately 10%
- A BMI of 30.0 or more indicates obesity
- A BMI of 40.0 or more indicates morbid obesity
There are a couple of drawbacks to BMI values:
- They tend to underestimate body fat in people who have lost muscle mass – such as
- They tend to overestimate body fat in people with muscular builds.
Another measurement used to determine obesity is waist-to-hip. In 2005, a large, multi-center, case controlled study was published in a leading medical journal, The Lancet.
This showed that measuring the waist-to-hip is more accurate than BMI as an indicator of risk for heart disease in people who are obese and of certain ethnicities. The study involved more than 29,000 participants from 52 countries.
While waist-to-hip measurement is currently not as commonly used as BMI, but that could change in the coming years.
How is obesity treated in adults?
There are several ways to treat or manage obesity. They include:
- A healthy diet
- Exercise over a sustained period of between 30 and 40 minutes five times a week.
- In certain cases drug therapy may be recommended
- Bariatric surgery, which involves reducing the capacity of the stomach. This is usually
considered only in patients who are extremely obese with serious associated health problems
- Laparascopic adjustable gastric banding, which is a simpler, less invasive procedure than Bariatric surgery. But again, it is typically considered only in extremely obese people.
How is obesity diagnosed and managed in children and youth?
Unfortunately, in the developed world there is a steadily increasing population of obese children and teenagers. Because this is a relatively new problem, studies have not yet been done to provide treatment guidelines.
Nevertheless, the causes of obesity don’t change in children. Inactivity, bad diet and bad eating habits, high calorie intake, an overweight parent or parents and genetics are all factors, just as they are in adults.
Introducing regular exercise and a healthy diet will go a long a way toward reducing your child’s weight. Benefits can be seen in losing between five and 10 percent of the total weight.
It is also important to remember that even if your child is overweight, he or she is more likely than a child of healthy weight to become obese as an adult.
For children, youth and adults, losing extra weight not only brings about many health benefits, it can also increase your energy and stamina and dramatically improve your quality of life.