Understanding Obesity: Causes, Effects, and Solutions



Obesity means having too much body fat. It is not the same as being overweight, which means weighing too much. A person may be overweight from extra muscle or water, as well as from having too much fat. Both terms mean that a person’s weight is higher than what is thought to be healthy for his or her height. Obesity is considered to be a major nutritional disorder in many parts of the industrialized world. It is a heterogeneous disorder, considered a disorder of energy balance. Obesity is defined as an abnormal or excessive fat accumulation that presents a risk to health. A measurement of obesity is the body mass index (BMI), a person’s weight (in kilograms) divided by the square of his or her height (in meters).

For adults, WHO defines overweight and obesity as follows:

  • Overweight is a BMI greater than or equal to 25;
  • Obesity is a BMI greater than or equal to 30.

For children under 5 years of age:

  • Overweight is weight-for-height greater than 2 standard deviations above WHO Child Growth Standards median;
  • Obesity is weight-for-height greater than 3 standard deviations above the WHO Child Growth Standards median.

For children aged between 5–19 years:

  • Overweight is BMI-for-age greater than 1 standard deviation above the WHO Growth Reference median;
  • Obesity is greater than 2 standard deviations above the WHO Growth Reference median.

Body mass index (BMI) is a tool that doctors use to assess if a person is at an appropriate weight for their age, sex, and height.


Overweight and obesity are major risk factors for a number of chronic diseases, including diabetes, cardiovascular diseases, and cancer. The worldwide prevalence of obesity nearly doubled between 1980 and 2008. According to country estimates for 2008, over 50% of both men and women in the WHO European Region were overweight, and roughly 23% of women and 20% of men were obese. Based on the latest estimates in European Union countries, overweight affects 30-70% and obesity affects 10-30% of adults. Estimates of the number of overweight infants and children in the WHO European Region rose steadily from 1990 to 2008. Over 60% of children who are overweight before puberty will be overweight in early adulthood. Childhood obesity is strongly associated with risk factors for cardiovascular disease, type 2 diabetes, orthopedic problems, mental disorders, underachievement in school, and lower self-esteem.

Psychological “Risk Factors” of Obesity

The etiological basis of eating disorders and obesity is usually a combination of psychosocial, environmental, and genetic or biological attributes. Individuals who suffer from psychological disorders (e.g. depression, anxiety, and eating disorders) may have more difficulty controlling their consumption of food, exercising an adequate amount, and maintaining a healthy weight. Food is often used as a coping mechanism by those with weight problems, particularly when they are sad, anxious, stressed, lonely, and frustrated. In many obese individuals, there appears to be a perpetual cycle of mood disturbance, overeating, and weight gain. When they feel distressed, they turn to food to help cope, and though such comfort eating may result in temporary attenuation of their distressed mood, the weight gain that results may cause a dysphoric mood due to their inability to control their stress. In addition to depression and anxiety, other risk factors include problematic eating behaviors such as “mindless eating,” frequent snacking on high-calorie foods, overeating, and night eating. Binge eating disorder (BED) is currently included in an appendix of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) and is characterized by recurrent episodes of eating during a discrete period of time (at least 2 days a week over a 6-month period), eating quantities of food that are larger than most people would eat during a similar amount of time, a sense of lack of control during the episodes, and guilt or distress following the episodes. BED is estimated to occur in approximately 2% of the general population and between 10% and 25% of the bariatric population. An important differentiation between BED and bulimia/anorexia is that BED is not associated with any regular compensatory behaviors, such as purging, fasting, or excessive exercise, so the majority of individuals with BED are overweight. Night eating is another disorder that can lead to significant weight gain, though night eating syndrome (NES) is not currently recognized as a distinct diagnosis in the DSM-IV-TR. First identified in 1955, NES is characterized by excessive nighttime consumption (> 35% of daily calories after the evening meal), unhealthy eating patterns, “morning anorexia,” insomnia, and distress. NES occurs in approximately 1% of the general population and an estimated 5-20% of the bariatric population. More recently, NES has been viewed as a disorder of circadian rhythm that includes a delay of appetite in the mornings and the continuation of appetite and overeating into the night.


Taking in more calories than your body burns can lead to obesity. This is because the body stores unused calories as fat. Obesity can be caused by:

  • Eating more food than your body can use
  • Drinking too much alcohol
  • Not getting enough exercise

Many obese people who lose large amounts of weight and gain it back think it is their fault. They blame themselves for not having the willpower to keep the weight off. Today, we know that biology is a big reason why some people cannot keep the weight off. Some people who live in the same place and eat the same foods become obese, while others do not. Our bodies have a complex system to keep our weight at a healthy level. In some people, this system does not work normally. We may feel that we are surrounded by things that make it easy to overeat and hard to stay active. Many people feel they do not have time to plan and make healthy meals. More people today work desk jobs compared to more active jobs in the past. People with little free time may have less time to exercise. Sometimes, medical problems or treatments cause weight gain, including: Underactive thyroid (hypothyroidism) or Medicines such as birth control pills, antidepressants, and antipsychotics. Etiology and pathogenesis of obesity. Obesity is the result of greater energy consumption than what the body uses. As this energy is stored, fat cells become enlarged, producing the pathology characteristic of obesity. The pathological increase in fat cells, in turn, produces altered levels of many peptide and nutrient signals that are responsible for the disease we call ‘obesity.’ The genetic makeup of humans also influences. For most patients, it is not possible to relate obesity to a specific cause. Leptin deficiency and defects in the leptin receptor produce human obesity. Defects in the pro-opiomelanocortin receptor system, the peroxisome proliferator-activated gamma receptor, the agouti-related peptide and some other rare genetic syndromes are also associated with human obesity. Of the genetic causes, the Prader-Willi syndrome is the most common. The hypothalamic lesion after a craniopharyngioma is the most common neuroendocrine cause. Endocrine disorders such as Cushing’s disease, polycystic ovary disease, and growth hormone deficiency can lead to an increase in body fat. In the modern world, exposure to a high-fat diet predisposes many people to obesity, and this problem is compounded by the low levels of activity that are now required for daily life.


Obesity can cause day-to-day health problems such as: Breathlessness, Increased sweating, Snoring, Inability to cope with sudden physical activity – Feeling very tired every day, Back and joint pain, Low confidence and self-esteem, Feeling isolated. Encourage the patients to exercise regularly. The patients need to have approximately 150 to 300 minutes of moderate-intensity activity per week in order to prevent weight gain. Encourage the patients to follow a healthy eating plan and focus on low-calorie, nutrient-dense foods. Analyze the food traps that cause food consumption of patients and try to raise the awareness of the patients. Monitor and record the weight of patients. Ensure that the patients follow the paths consistently and strictly. To prevent and treat obesity in the clinical setting. Essential element: 1. Assessment and technical assistance for clinical practices; 2. A registry of overweight and obese patients; 3. Clinical guidelines that are relatively simple and easy to follow; 4. Data metrics and reports from providers and health care systems, including adherence to guidelines; 5. Expanded health teams that include dietitians, health coaches, social workers, medical assistants, and community health workers; and 6. Physician training and engagement in advocacy around evidence-based community intervention. Changes to diet and exercising are the main treatments. Diet quality can be improved by reducing the consumption of energy-dense foods, such as those high in fat or sugars, and by increasing the intake of dietary fiber. Medications can be used, along with a suitable diet, to reduce appetite or decrease fat absorption. If diet, exercise, and medication are not effective, a gastric balloon or surgery may be performed to reduce stomach volume or length of the intestines, leading to feeling full earlier or a reduced ability to absorb nutrients from food.



Individual Behavior

Physical Activities, Eating Habits, Educational Level, Coping with Stress


– Health Behavior: The behaviors that play a significant role in achieving and maintaining a healthy weight are Nutrition and Eating Behaviors: Proper nutrition can provide children with energy and strong, healthy bodies, prevent higher cholesterol and blood pressure levels, and decrease the risk of chronic disease. Physical Activity Behaviors: Regular physical activity helps to build healthy bones and muscles and leads to an active lifestyle is likely to reduce many health problems. Sedentary Behaviors: Any activity that requires very low energy expenditure and that occurs while sitting or reclining. – Individual Demographic Characteristics: Differences have been seen in the prevalence of overweight and obesity by sex, age, race, and ethnicity.


– Family Characteristics and Health Behaviors: Parents are the key to developing a home environment that fosters healthful eating and physical activity among children and adolescents. – Home Environment: The home environment is undoubtedly the most important setting in relation to shaping children’s eating and physical activity behaviors. – Extracurricular Activities: Extracurricular activities allow children additional opportunities for physical activities and socialization with their peers.

Community or Neighborhood Level

– Physical or Built Environment: The neighborhood built environment is comprised of buildings, roads, open spaces, and sidewalks and can provide opportunities or barriers to health. The physical environment can be helpful or harmful to a child’s health by facilitating or hindering physical activity and healthy eating behaviors. – Social Environment: The social environment of the community can have either a positive or negative influence on health behavior. Communities can provide an excellent level of support and motivation to be healthy and active.



Tier 1 (primary care)

consists of primary care provision of obesity prevention, with basic interventions provided by GPs, health visitors, school nurses, and leisure services.

Tier 2 (secondary care)

consists of community-based obesity services led by dietitians and exercise therapists.

Tier 3 (tertiary care)

weight management services consist of multidisciplinary groups, including a medical clinician who could be a specialist GP or a hospital physician.

Tier 4 (special programs)

consists of hospital-based specialist care, which is largely obesity surgery but in many institutions includes specialist medical services.