Where is the line in the sand and when is it time to take action? It is fairly widely accepted that the difference between healthy weight, overweight and obesity can be determined using Body Mass Index. BMI is a height to weight ratio. For most people this ratio correlates to their amount of body fat.
For example, for an adult male who is 6' tall, a weight of less than 136 pounds would be considered underweight; 137-184 would be in normal weight range; 185-220 would be in overweight range; and over 221 pounds would be considered obese. Using the BMI as a measurement of obesity means that many people who do not think of themselves as obese will fall into the obese range.
To calculate your BMI divide your weight in kilograms by your height in meters. A BMI of less than 20 is considered underweight; 20-25 is considered normal weight; 25- 30 is considered overweight; and over 30 is considered obese.
Using BMI to determine if a child or teen is overweight is more complicated. For children and teens the amount of body fat changes with age and differs between boys and girls. For children and teens there are not set weights according to height that indicate overweight or obese ranges. The differences according to age and sex are taken into account in the BMI-for-age growth charts, which show a BMI number as a percentile for a child or teen's sex and age.
If a child or teen is in the 5th percentile or less they are considered underweight, from the 5th to 85th percentile they are considered normal weight, 85th to 95th percentile they are considered overweight and above the 95th percentile they are considered obese.
The BMI can be misleading if you are very active and you have a muscular build. Muscle weighs more than double what fat weighs. If you suspect that your BMI is unfairly placing you in an overweight or obese range, then try calculating your waist to hip ratio as a check.
To determine your waist to hip ratio: measure your hips at the widest part and measure your waist at the smallest part (close to your bellybutton). Divide your waist measurement by your hip measurement. A ratio of less than 0.8 for women and less than1.0 for men is considered healthier. It is also important to remember that a waist measurement of over 35 inches for women and 40 inches for men is a danger signal.
Generally if you weigh more than 30 pounds over your normal weight you would be considered obese. Being overweight or obese puts you at greater risk for health problems such as diabetes, high blood pressure and high cholesterol. Losing even a small amount of weight can help reduce the risk of disease.
The easiest time to take action for weight control is before entering the obese range, but it is never too late to modify habits and improve your heath.