I'm overweight. BMI and Waist to hip ratio both indicate that fact.
At 5'7.5" and 12st 131bs or 181 pounds (was 13st 8lbs a few months ago!) my BMI is 27.9.
BMI is Body Mass Index defined by dividing weight in kilogrammes by my height in metres squared. BMI = kg/m2.
My current weight loss goal is to stabilise at 155 pounds (11st 1lb) giving a BMI of 23.9.
For a BMI of 24.9 my weight would be 161.5 pounds (11st 7.5lbs).
For a BMI of 20.9 my weight would be 135 pounds (9st 9Ibs).
I use a simple BMI calculator.
Back in February 1987 I was 11st 13lbs (BMI 25.8 - overweight) and by July 1987 in my first diet (strict calorie counting + exercise) I lost 2 stone to 9st 13lbs (BMI 21.4 - normal weight). Sharon said I looked emaciated at this weight!
By August 1990, 3 years on, I had put on all the weight I had lost in 1987 diet.
Sharon's weight today is 10st 2Ibs, 5'1" - BMI is 26.6. A 24.9 BMI for her is 9st 6Ibs. A 23.9 BMI would be 9st.
But how were these figures calculated in the first place? And is their any variation of these classifications? Wikipedia BMI page has answers.
the following are common definitions of BMI categories:
-
- Starvation: less than 15
- Underweight: less than 18.5
- Ideal: from 18.5 to 25
- Overweight: from 25 to 30
- Obese: from 30 to 40
- Morbidly Obese: greater than 40
During the past 20 years, says CDC obesity among adults has risen significantly in the United States. The latest data from the National Center for Health Statistics show that 30 percent of U.S. adults 20 years of age and older—over 60 million people—are obese. The U.S. National Health and Nutrition Examination Survey of 1994 indicates that 59% of American men and 49% of women have BMIs over 25.
Being overweight increases the risk of many diseases and health conditions, including the following:
- Hypertension
- Dyslipidemia (for example, high total cholesterol or high levels of triglycerides)
- Type 2 diabetes
- Coronary heart disease
- Stroke
- Gallbladder disease
- Osteoarthritis
- Sleep apnea and respiratory problems
- Some cancers (endometrial, breast, and colon)
The BMI has become controversial because many people, including physicians, have come to rely on it for medical diagnosis - but that has never been the BMI's purpose. It is meant to be used as a simple means of classifying sedentary (physically inactive) individuals with an average body composition.
I wouldn't say i was physically inactive (how is that defined?) - I walk Jazzie the dog most days for an hour or so and ride a bike occassionally on a CRABS ride.
Have i got an average body composition?
BMI accuracy in relation to actual levels of body fat is easily distorted by such factors as fitness level, muscle mass, bone structure, gender, and ethnicity. As a general rule, developed muscle contributes more to weight than fat and the BMI does not account for this. Therefore a person with more muscle mass, such as a body-builder, will seem to be overweight. People who are mesomorphic tend to have higher BMI numbers than people who are endomorphic, because they have greater bone mass and greater muscle mass, respectively, than do endomorphic individuals.
Similarly, an ectomorphic individual could conceivably receive an unhealthily low reading, when in fact their body type makes them naturally thin no matter what they eat.
International BMI variations
These recommended distinctions along the liner scale may vary from time to time and country to country. In 1998, the U.S. National Institutes of Health brought U.S. definitions into line with World Health Organization guidelines, lowering the normal/overweight cut-off from BMI 27.8 to BMI 25. This had the effect of redefining 30 million Americans, previously "technically healthy" to "technically overweight". It also recommends lowering the normal/overweight threshold for South East Asian body types to around BMI 23, and expects further revisions to emerge from clinical studies of different body types.
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