Many people want to know how much they ideally should weigh and whether their weight jeopardizes their health. It may seem like a simple question, but experts can't always agree on the answer. Dietitians and physicians try to identify the weight associated with good health and longevity, according to Eleanor Whitney and Sharon Rolfes in the text, "Understanding Nutrition." Experts may consider not only weight within a suggested range, but also fat distribution associated with low risk of illness or early death and chronic disease risk factors.
Identification
The ideal weight for a person is that weight believed to be optimal for health. It is based primarily on height, but other considerations include gender, age, body frame size and lean body mass.
Determination Methods
Determine ideal weight for height by comparison with reference standards such as the Metropolitan Life Insurance Tables or the National Health and Nutrition Examination Survey, NHANES, I and II percentiles. Dieticians often use a third option, the Hamwi method, as a quick and easily calculated rule of thumb.
Hamwi Calculation
Estimate the ideal weight for women as 100 lbs. for the first 5 feet of height plus 5 lbs. for every inch over 5 feet, according to Kathleen Mahan and Sylvia Escott-Stump, in "Krause's Food, Nutrition, & Diet Therapy." Estimate the ideal weight for men as 106 lbs. for the first 5 feet of height and 6 lbs. for every inch over 5 feet. Adjust this estimate of ideal weight according to the person's body frame size for both men and women by adding 10 percent for a large frame or subtracting 10 percent for a small frame.
For example, the ideal body weight for a small-frame woman who is 63 inches tall would be 100 lbs. for the first 5 feet, or 60 inches, plus 5 lbs. times 3 additional inches, for a total of 115 lbs. Since she has a small frame, subtract 10 percent of 115, or 11.5 pounds. Her ideal weight, according to the Hamwi method, is 115 minus 11.5, or 103.5 pounds.
Frame Size
Body frame size, designated small, medium or large, can be determined by three methods. For a person of either sex, estimate frame size quickly by having the person wrap the thumb and fingers of one hand around the smallest part of the other wrist. If the finger and thumb overlap, the person has a small frame. If the finger and thumb barely touch, the frame size is medium. If the finger and thumb do not touch, the person has a large frame.
More accurate measures of frame size based on wrist circumference or elbow breadth can be performed by a trained dietitian or physician with precise positioning of the arm, elbow and wrist, formula calculations and comparison with reference standards.
Cautions
Metropolitan Life Insurance Tables reflect the height and weight of adults 25 to 59 years old and wearing shoes with 1-inch heels. These two considerations are often overlooked and can invalidate the results for a person measured without shoes or a person outside of that age range.
According to Bhumika Shah, Kathryn Sucher and Clarie B. Hollenbeck, authors of an article in the June 2006 issue of "Nutrition in Clinical Practice," few studies have compared and validated the numerous height-weight tables and formula calculations.
The ideal weight should not be used alone but in concert with other measures of healthy body weight.
References
- "Understanding Nutrition, Ninth Edition"; Eleanor Noss Whitney and Sharon Rady Rolfes; 2002
- Metropolitan Life Insurance Tables
- CDC: NHANES II Height and Weight
- "Krause's Food, Nutrition, & Diet Therapy, 10th Edition"; Mahan and Escott-Stump; 2000
- Nutrition in Clinical Practice: Comparison of Ideal Body Weight Equations and Tables
Member Comments