Risk level

From the BMI, waist and hips, the risk level for chronic non-communicable diseases (cardiovascular diseases, type II diabetes, breast cancer, colon cancer) can be concluded.

Assessment of the risk level according to BMI and the waist to hip ratio

BMI risk level 
≥ 0,70 / ≥ 0,80 > 0,86 / > 0,95
BMI < 18,5    
18,5 <=BMI < 25 risk increased risk
25 <= BMI < 30 increased risk high risk
30 <= BMI < 35 high risk very high risk
35 <= BMI < 40 very high risk very high risk
BMI >= 40 extremely high risk extremely high risk

Klasifikacija telesne mase glede na ITM po merilih Svetovne zdravstvene organizacije

Classification BMI(kg/m2)
Limit Additional limits
Insufficient body weight
<18,50 <18,50
Extremely low body weight <16,00 <16,00
Slightly low body weight 16,00 - 16,99 16,00 - 16,99
Low body weight 17,00 - 18,49 17,00 - 18,49
Suitable body weight
18,50 - 24,99 18,50 - 22,99
23,00 - 24,99
Exessive body weight
≥25,00 ≥25,00
Increased body weight 25,00 - 29,99 25,00 - 27,49
27,50 - 29,99
Obesity ≥30,00 ≥30,00
Obesity I 30,00 - 34-99 30,00 - 32,49
32,50 - 34,99
Obesity II 35,00 - 39,99 35,00 - 37,49
37,50 - 39,99
Obesity III ≥40,00 ≥40,00

Insufficient body weight

A healthy individual with BMI under 18.5 kg/m2 should gain weight gradually. To achieve a normal BMI or normal nourishment, energy intake should be increased. Body weight should be increased by approximately 0.5 kg per week, which means increasing daily energy intake by approximately 350 to 500 kcal. The person should be moderately physically active because exercise increases the appetite. Equally important is the proper diet regime (regular daily meals, i.e. 3 to 5 daily meals).
Underweight people with disease should gain weight under medical supervision or in consultation with their doctor.

The consequences of malnutrition due to the loss of body weight could be fatal, particularly for chronic patients:

Share of losses of lean body weight Complications Associated mortality
10 % impaired immunity, increased risk of infection 10 %
20 % slower wound healing, weakness, infection 30 %
30 % too weak to sit, bedsores, poorly healing wounds 50 %
40 % death, pneumonia 100 %

Suitable body weight
For a healthy individual with BMI between 18.5 and 25 kg/m2, the amount of food and physical activity is appropriate. Person should ensure a balanced diet.

Exessive body weight

If it is found that a healthy person with a BMI between 25 and 40 kg/m2 is overweight, obese and/or has an increased waist circumference, a healthy weight loss is recommended with appropriately reduced energy intake and increased physical activity.

Obesity is associated with increased risk of developing type 2 diabetes, breast cancer, colon, rectum, prostate and other cancers, hypertension and cardiovascular diseases. Obesity is also a risk factor for development of liver diseases, gallstones, orthopedic complications, dermatological changes, neurological and hormonal disorders and psychosocial consequences.

It should be mentioned that the loss of excess body weight:

  • improves prevention and management of chronic non-communicable diseases by 10 %;
  • by 10 kg in diabetes increases glucose utilization by 37 %.
Weight loss should be gradual, in accordance with the guidelines of optimal weight loss, encouraging a weight loss from 500 to 700 g per week or not more than 2 to 2.5 kg per month. Reduction diet is based on a reduced daily energy intake. Weight loss of 1 kg requires energy intake reduced by 7000 kcal (29,400 kJ). In case that the purpose of the reduction diet in a person is a loss of two kilograms in one month, it means that the individual needs to reduce monthly energy intake by 14,000 kcal (58,800 kJ) or on average 467 kcal/day (1960 kJ/day). 
Studies shows that a daily diet with less than 1200 kcal is not successful long-term in maintaining the new weight.

Regular daily physical akctivity (30-60 minutes) is essential for reducing body weight. It must be adjusted individually, according to each person's abilities.

Informative calculation of the heart beat:
a person's highest heart beat = 220 - age * (60 - 75 % of the highest heart beat) which equals the interval from (220 - age) * 0.6 to (220 - age) * 0.75

Warning: If you have a medical problem, expert evaluation of the health status and physical performance should be done before regular physical activity. Weight gain may also be a consequence of the increased muscle mass (due to physical activity) or water retention.

A healthy person with BMI above 40 kg/m2 must necessarily lose weight. Please, consult your doctor.