Waist circumference alone cannot indicate that you have a medical condition or that youll develop one in the future but it can help you and your healthcare provider to determine where fat is located on your body and if that fat may cause health. For example a man whose height is over 5 5 and wrist is 6 would fall into the small boned category.

Official Navy Abdominal Circumference Measurement Demonstration
How do you measure body circumference. Steps in measuring your body circumference measuring your chest circumference. Wrap the tape measure around the widest part of your upper arm from front to back and around to the start point. To determine the body frame size measure the wrist with a tape measure and use the following chart to determine whether the person is small medium or large boned. Body frame size is determined by a persons wrist circumference in relation to his height. To measure the circumference of your head choose a flexible plastic tape measure that wont stretch to get an accurate measurement. Less than 35 inches for women.
Waist circumference is considered a good estimate of your body fat especially your internal fat deposits and your likelihood of developing weight related disease. Measuring the circumference of certain body parts is a simple method of body fat estimation. Less than 40 inches for men. A basic way to measure body fat percentage is by using a soft tape measure like the kind youd use for sewing to record measurements of different parts of the body. Make sure that the ends meet and measure. Two methods that are commonly used to estimate whether you are a healthy weight or not are body mass index bmi and waist circumference.
To help reduce your risk of medical complications your waist circumference should be. Measure the circumference of your arm. Place one end of the tape measure at level of your bust on the fullest level. For example the us army uses a body fat calculation that simply requires an individuals age height. When youre ready to measure place the tape so it rests 1 inch above the tops of your ears 3 inches above the tops of your eyebrows and directly across the back of your head where you can feel a small bump or bone. Once these measurements are obtained use the following formulas to calculate an estimate of body fat.
Measure the circumference of the subjects hips at the largest horizontal measure. You may be tempted to cheat by lowering the tape measure a few inches but then you wont get an accurate measurement. Wrap the tape measure around the body under the armpit and over the scapula or shoulder blades at the back and back to the front of the bust line. Measuring the size of your waist can help you to understand your risk for certain health conditions that are related to your weight. On the other hand if youre muscular and have a high bmi but suspect you have a lower body fat percentage waist circumference is a great way to determine your risk.