What is BMI?Body Mass Index(BMI) is value derived from persons weight and height. The result of BMI measurement can give an idea about weather a person has correct weight for their height.How to Calculate BMI?BMI calculation is based on simple formula using persons weight and height. The formula for BMI = kg/m2 where kg is persons weight in kilograms and m2 is their height in meters squared. In simplified format it would beBMI = (Weight in Kilograms)/(Height in meters * Height in meters)For example if persons weight is 68kg and height is 172cm then BMI = 68/(1.72*2) = 23 BMI calculator indicate whether person falls under healthy weight, underweight or overweight. If persons BMI is out of healthy range, their health risk may significantly increases.BMI Range for adultsBMI : weight statusBelow 18.5 : Underweight18.5 – 24.9 : Normal or Healthy Weight25.0 - 29.9 : Overweight30.0 & above: ObeseDoctors uses BMI too for- evalution for diet and physical acitivty- cadiovascular disease and other health related problems- measure fat in bodyHealth risks for extra weightraises blood pressure and cholesterol and triglyceride levelsit can make diabetes and other health problemshypertension or high blood pressuretype 2 diabetescoronary heart diseasegallbladder diseaseosteoarthritissleep apnea and respiratory problemsHealth risks for under weightmalnutrition, anemia or vitamin deficienciesosteoporosis from too little vitamin D and calciumDecreased Immune Systemfertility issues caused by irregular menstrual cyclesgrowth and development issues in children and teenagersWho shouldnt use a BMI calculatorBMI should not be used for muscle builders, athletes, pregnant women, the elderly or young children.This is because BMI does not take into account whether the weight is carried as muscle or fat its just the number. Those with a higher muscle mass, such as athletes, may have a high BMI but not be at greater health risk. Those with a lower muscle mass, such as children who have not completed their growth or the elderly who may be losing some muscle mass may have a lower BMI.