Frequently Asked Questions about Obesity

According to a recent study, around a fifth of adults worldwide will be obese by 2025. Thus, these frequently asked questions about obesity will probably be asked with increasing frequency in the years to come.


Frequently Asked Questions about Obesity

1.       What is obesity?

This is a condition characterized by excessive body fat and weight. Body mass index and waist circumference are often used to determine weight status.

2.       What is body mass index?

A person’s body mass index (BMI) is calculated by dividing his or her weight in kilograms by the square of his or her height in meters. Though not a direct measurement of body fat, BMI has been shown to be moderately correlated with – as well as cheaper than – more direct approaches. BMI is a screening, not a diagnostic, tool.

BMI (adults)

Weight status

Below 18.5







Obese (class I).


Obese (class II).

40.0 and higher

Extreme obesity (class III).


3.       Are there exceptions to the above BMI-determined weight statuses?

Athletes may have a high BMI due to increased muscularity as opposed to increased body fatness.

4.       How is BMI interpreted for children?

The same formula to calculated BMI for adults is used for children, but while the adult interpretation of BMI does not depend on sex or age, children and teen's BMI has to be age and gender-specific because the amount of body fat changes with age and the amount of body fat differs between girls and boys. Obesity among 2- to 19-year-olds is defined as a BMI at or above the 95th percentile of children of the same age and sex in this 1963 to 1994 reference population.

5.       At which waist circumference is someone at a higher risk for obesity-related conditions?

·         More than 40 inches for men.

·         More than 35 inches for non-pregnant women.

6.       How is waist circumference measured?

  • Stand and place a tape measure around the middle, just above the hipbones.
  • Make sure the tape is horizontal around the waist.
  • Keep the tape snug around the waist, but not compressing the skin
  • Measure waist just after breathing out.

7.       What other ways are there to measure body fat?

·         Skinfold thickness measurements with calipers.

·         Underwater weighing.

·         Bioelectrical impedance.

·         Dual energy x-ray absorptiometry.

·         Isotope dilution.

8.       What causes obesity?

·         Lack of physical activity.

·         Poor diet and unhealthy eating habits.

·         Prader-Willi syndrome, Cushing's syndrome, and other disorders (rarely).

9.       What are the symptoms of obesity?

·         Clothes feel tight.

·         The scale shows weight gain.

·         Extra fat around the waist.

10.   What are the risk factors for obesity?             

·         Genetics.

·         Family history.

·         Physical inactivity.

·         Unhealthy diet.

·         Certain conditions and medications.

·         Socio-economic factors.

·         Age.

·         Pregnancy.

·         Smoking cessation.

·         Poor sleep.

11.   What are the potential complications of obesity?

  • High triglycerides and low high-density lipoprotein (HDL) cholesterol.
  • Obesity Hypoventilation Syndrome.
  • Type 2 diabetes.
  • High blood pressure.
  • Metabolic syndrome.
  • Heart disease.
  • Stroke.
  • Cancer, including of the uterus, cervix, endometrium, ovaries, breast, colon, rectum, esophagus, liver, gallbladder, pancreas, kidney and prostate.
  • Breathing disorders such as sleep apnea.
  • Chronic inflammation and increased oxidative stress.
  • Poor quality of life.
  • Body pain.
  • Problems with physical functioning.
  • Gallbladder disease.
  • Gynecological problems, like infertility and irregular periods.
  • Erectile dysfunction and sexual health issues.
  • Non-alcoholic fatty liver disease.
  • Osteoarthritis.
  • Depression.
  • Disability.
  • Shame.
  • Guilt.
  • Social withdrawal.
  • Loss of work productivity.
  • Death.

12.   What are the potential complications of obesity in children?

·         High blood pressure and high cholesterol.

·         Cardiovascular disease (CVD).

·         Increased risk of impaired glucose tolerance, insulin resistance and type 2 diabetes.

·         Breathing problems, such as sleep apnea, and asthma.

·         Joint problems and musculoskeletal discomfort.

·         Fatty liver disease, gallstones, and gastro-esophageal reflux.

·         Psychological stress such as depression, behavioral problems, and issues in school.

·         Low self-esteem and low self-reported quality of life.

·         Impaired social, physical, and emotional functioning.

·         Children who are obese are more likely to become obese adults.

13.   How is obesity diagnosed?

·         Health history.

·         Physical exam.

·         BMI calculator.

·         Child and teen BMI calculator.

·         Measuring waist circumference.

·         Blood tests.

14.   How is obesity treated?

  • Dietary changes.
  • Exercise and activity.
  • Behavior change.
  • Prescription weight-loss medications.
  • Weight management medical supplies online.
  • Weight-loss surgery.

15.   Which specialists may be involved in the treatment of obesity?

  • An endocrinologist.
  • A registered dietitian or nutritionist.
  • An exercise physiologist or.
  • A bariatric surgeon.
  • A psychiatrist, psychologist, or clinical social worker.

16.   How to cope with obesity?

  • Expressing one’s emotions by keeping a diary.
  • Connecting with others.
  • Joining a support group.
  • Establishing and focusing on realistic goals.
  • Managing stress.

17.   What qualifies as “realistic goals”?

·         Losing 5%-10% of current body weight.

·         A weight loss of 1-2 lbs a week.

18.   How many calories a day are safe?

·         1,000 to 1,200 calories a day will help most women lose weight safely.

·         1,200 to 1,600 calories a day will help most men lose weight safely. 

19.   How can obesity be prevented?

  • Regular exercise (60 minutes a day for children and 150 minutes per week for adults).
  • Eating healthily.
  • Identify eating triggers.
  • Monitor weight.

20.   What does a healthy diet include?

  • Fat-free and low-fat dairy products.
  • Protein foods.
  • Whole-grain foods.
  • Fresh, canned, frozen, or dried fruit and vegetables.

21.   What foods should limited or avoided?

  • Fatty cuts of meat.
  • Poultry with the skin.
  • High-fat dairy products.
  • Lard, coconut, and palm oils.
  • Trans fats.
  • Cholesterol.

22.   How common is obesity?

·         Over one-third (34.9% or 78.6 million) of U.S. adults are obese.

  • Approximately 17% (or 12.7 million) of children and adolescents aged 2—19 years are obese. 
  • Worldwide obesity has more than doubled since 1980.
  • In 2014, more than 1.9 billion adults, 18 years and older, were overweight, of which over 600 million were obese.
  • 39% of adults aged 18 years and over were overweight in 2014, and 13% were obese.
  • Most of the world's population live in countries where overweight and obesity kills more people than underweight.
  • 42 million children under the age of 5 were overweight or obese in 2013.

23.   How does the prevalence of obesity vary among ethnic and age groups?

  • Non-Hispanic blacks have the highest age-adjusted rates of obesity (47.8%) followed by Hispanics (42.5%), non-Hispanic whites (32.6%), and non-Hispanic Asians (10.8%)
  • Obesity is higher among middle age adults, 40 to 59 years old (39.5%) than among younger adults, age 20 to 39 (30.3%) or adults over 60 or above (35.4%) adults.

24.   What is the relationship between obesity and social and economic status and education level?

  • Among non-Hispanic black and Mexican-American men, those with higher incomes are more likely to have obesity than those with low income.
  • Higher income women are less likely to have obesity than low-income women.
  • There is no significant relationship between obesity and education among men.
  • Among women, however, there is a trend—those with college degrees are less likely to have obesity compared with less educated women.
  • Obesity prevalence among children whose adult head of household completed college was approximately half that of those whose adult head of household did not complete high school in 1999–2010.
  • Among non-Hispanic white children, the lowest prevalence of obesity was observed among those whose adult head of household completed college; however, this was not the case for non-Hispanic black children.
  • Over time, the prevalence of obesity among girls whose adult head of household had not finished high school increased from 17% (1999–2002) to 23% (2007–2010), but decreased for girls whose adult head of household completed college from 11% (1999–2002) to 7% (2007–2010). There was not a similar finding among boys.
  • Obesity prevalence was the highest among children in families with an income-to-poverty ratio of 100% or less (household income that is at or below the poverty threshold), followed by those in families with an income-to-poverty ratio of 101%-130%, and then found to be lower in children in families with an income-to-poverty ratio of 131% or larger.
  • Obesity prevalence on the basis of family income among children from low-income households was: 14.2% among children in families with an income-to-poverty ratio of less than or equal to 50%; 14.5% among children in families with an income-to-poverty ratio of 51–100%; 13.4% among children in families with an income-to-poverty ratio of 101–130%; 12.4% among children in families with an income-to-poverty ratio of 131–150%; 11.8% among children in families with an income-to-poverty ratio of 151-185%.

25.   How much does obesity cost?

·         The estimated annual medical cost of obesity in the United States was $147 billion in 2008.

·         The medical costs for obese people were $1,429 higher than those of people with normal weight.


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