Calculating Your BMI

What is BMI? You may have heard the term. BMI is an acronym for Body Mass Index, a mathematically derived measurement that calculates an individual's weight to height ratio. Here's how to do it.

Typically, doctors use your BMI as an indicator to estimate your health risk from obesity related diseases and conditions, including cardiovascular disease, hypertension and high cholesterol. Although it's not an absolute indicator (your body fat percentage should be considered as well) BMI is usually the first analysis done to estimate your weight-related health risks.

Calculating your BMI

First, grab your calculator. It's important to be accurate - and honest - in your answers to get a useful result or you can go to DietingPlan.com's BMI calculator and let it do the work for you!

1. Write down your weight, in pounds.
   
2. Multiply this number times 703.
   
3. This is Answer A.
   
   
4. Write down your height, in inches.
   
5. Square that number (Multiply it times itself).
   
6. This is Answer B.
   
   
7. Divide Answer A by Answer B. This is your BMI.

Let's look at a specific example. We'll calculate the BMI of a woman who is 5'5" and 145 pounds.

Weight in pounds = 150 x 703 = 105,450

Height in inches = 64 Squared x 64 = 4,096

Answer A = 105,450 ¸ Answer B = 4,096 = BMI = 25.7

So in this case, our hypothetical woman's BMI is 25.7. Let's take a look at what that value means.

Understanding Your Results

So just what does your BMI mean to you? The National Institute of Health (NIH) recently revised the BMI guidelines. These guidelines state that anyone with a BMI of 25 or greater is at risk for weight-related health problems, and should assess their overall health and begin a proactive program to address their diet. According to the NIH, an astounding 97 million American adults fall into this category (a BMI of 25 or greater).

The following is an excerpt defining these values, and their correlating treatment recommendations, from Lifespan.org.

BMI = 30 or greater

Health Risk: High
You may be at significantly increased risk of obesity-related disease. A weight loss strategy including calorie reduction, increased physical activity and behavior therapy can help reduce these health risks.

BMI = 27-30

Health Risk: Moderate/High
You may be at increased risk for cardiovascular disease, hypertension and high blood cholesterol. It may also be appropriate to modify diet and exercise habits to reduce health risks.

BMI = 25-26

Health Risk: Low/Moderate
You may be at slightly increased risk for cardiovascular and other diseases. While there is no evidence to suggest a weight loss program is needed, prevention of any further weight gain is recommended.

BMI = 19-24

Health Risk: Minimal/Low
Your BMI number indicates you are within a healthy weight range, and do not need to consider a weight reduction plan for health-related reasons.

BMI = 18 or below

Health Risk: High
Your low BMI number indicates your weight, in relation to your height, may be below the safety minimum for your body type."

If your BMI indicates you are potentially at risk, you should talk to your doctor about your results and discuss a program that is appropriate for you. Bear in mind that BMI is only a first-glance indicator, and that body composition (percentage of lean muscle mass to fat) may be a factor as well - even for persons in the low risk category!

By tuning into your body, and calculating your BMI you have taken a positive step toward understanding your body and your health. Talk to your doctor about your personal habits, and work together to devise a plan for healthy eating and exercise that fits with your lifestyle. Today can be the first day in your journey to a healthier body!