Obesity is increasing at an alarming rate, this is really a potential threat in the future that reduces human life expectancy and quality of life, leading to a series of consequences for other diseases such as: High blood pressure, heart failure, diabetes, cancer…

1. How is obesity defined?

Overweight and obesity are defined by the WHO-World Health Organization as an abnormal or excessive accumulation of fat that may impair health.

Body mass index (BMI) is a simple index of weight for height that is commonly used to classify overweight and obesity in adults.

1.1 For adults

Overweight is a BMI greater than or equal to 25 and obesity is a BMI greater than or equal to 30.

1.2 For children

• For children under 5 years of age: Overweight is a weight-for-height greater than 2 standard deviations above the mean. WHO Child Growth Standards; and obesity is a weight-for-height greater than 3 standard deviations above the mean. WHO Child Growth Standards.
• Children aged 5 – 18 years: Overweight is a BMI-for-age greater than 1 standard deviation above the WHO growth reference mean; and obesity greater than 2 standard deviations above the mean above the WHO growth reference.

Childhood obesity

2. Causes of obesity

Body weight changes show that if the energy intake is greater than the energy consumed, weight gain will occur.

2.1 Obesity is familial

Recent studies show that obesity has a genetic component (polygenic inheritance). If the father and mother are obese, the risk of their children being obese is up to 80%. Only about 7% of people are obese while their parents are normal.

In addition, lack of exercise plays a very important role in the process of obesity, scientific development, advances in information technology and transportation make people less active. Children gain weight quickly partly due to the role of audio-visual media: television, games and even schools pay little attention to physical activity subjects.

2.2 Due to neuroendocrine

• Hypothalamus: Causes obesity when damaged, rare disease.
• Polycystic ovary: Polycystic ovary causes menstrual disorders, hypertension, increased androgen, insulin resistance and obesity in 50% of patients
• Hyperadrenocorticism (Cushing’s syndrome).
• Hypothyroidism: Hypothyroidism causes electrolyte and water metabolism disorders, reduces sodium and retains water causing weight gain, which is completely different from weight gain due to obesity.

Thyroid disease causes obesity

• Endocrine pancreatic tumor (insulinoma): Due to increased insulin causing hypoglycemia and the patient has to eat a lot leading to weight gain.
• Hypergonadism syndrome (Babinski – Froehlich).

Patients with endocrine and metabolic disorders such as: Adrenal cortex tumor, menopause, sugar metabolism disorders, lipid disorders…etc will stimulate fat tissue formation. The formation of fat tissue in the body causes an increase in the need for sugar, leading to an increase in the need for insulin, the increase in these two substances stimulates fat tissue formation and forms a pathological spiral that is very difficult to treat.

2.3 Genetic obesity

Leptin production gene mutation or Leptin Receptor mutation.

Other gene mutations:

• POMC synthesis gene.
• Prohormone convertase – 1 (PC – 1) production gene
• Me – 4 Receptor.
• PPAR – 2 (Peroxisome Proliferator Activator – receptor 2 ).

Obesity caused by genetic factors

3. What are the consequences of being overweight and obese?

Increased BMI is a major risk factor for non-communicable diseases such as:

• Cardiovascular disease (mainly heart disease and stroke), which was the leading cause of death in 2012;
• Diabetes
• Musculoskeletal disorders (especially osteoarthritis – a highly prevalent degenerative joint disease)
• Certain cancers  (including endometrial, breast, ovarian, prostate, liver, gallstone, kidney, and colon).

Overweight in children is associated with a higher risk of obesity, premature death and disability in adulthood. But in addition to increased risk in the future, obese children also have difficulty breathing, an increased risk of fractures, high blood pressure, early signs of cardiovascular disease, insulin resistance and psychological effects.

4. How can obesity be reduced?

Overweight and obesity, as well as related diseases, are largely preventable by making healthy food choices and regular physical activity the easiest (most accessible, available and affordable) option, thus preventing overweight and obesity.

At the individual level, people can:

• Limit their energy intake from total fat and sugar;
• Increase their intake of fruits and vegetables, as well as legumes, whole grains and nuts;
• Participate in regular physical activity (60 minutes a day for children and 150 minutes spread out over the week for adults).