Body mass index, or BMI, is a tool for estimating a person’s body composition. High percentages of body fat can indicate higher risks for type 2 diabetes, heart disease, sleep apnea and other weight-related conditions. But BMI is just one of several numbers to consider when looking at a person's health. Consider: a person is relatively thin, their BMI is normal, and yet they have high blood pressure. Or this: a person is heavy-boned and also muscular. The odds are, their BMI will read as high when they may be perfectly healthy for their body type. So BMI is far from the whole picture and it can be completely wrong in many cases. So here are a few other numbers to take into account.
Waist-hip ratio blows BMI out of the water. One study showed waist-hip ratio was a far better predictor of cardiovascular events than BMI. In fact, that same study found BMI alone to be useless in predicting heart attacks.
You can calculate your waist-hip ratio by dividing the length of your waist circumference by the length of your hip circumference. Measure the widest spot for each. Waist-hip ratios that fall below .85 for women and .90 for men are considered healthy. Anything over 1.0 puts you at risk for complications from heart disease.
Blood pressure is measured by taking two readings. The first number is the systolic blood pressure, which measures how forcefully blood pumps through arteries during heartbeats. The second number is the diastolic blood pressure, which measures that same force but between heartbeats. Readings that fall below 120/80 mm Hg (millimeters of mercury on the blood pressure gauge) are generally healthy.
Diastolic blood pressure readings between 120 mm Hg and 129 mm Hg are considered elevated and may lead to hypertension, which comes in three stages:
Hypertension can harm more than the cardiovascular system. Left untreated, hypertension can lead to damage in the kidneys, eyes and even the brain.
Resting heart rate is the number of beats the heart makes per minute when the body is at rest. A healthy resting heart rate is usually between 60 and 100 beats per minute. Athletes and people taking beta-blockers may have lower numbers, but in most people, readings below 60 beats per minute can be a sign of a medical emergency.
Tachycardia, or a resting heart rate above 100 beats per minute, can also be dangerous. This can have numerous causes, so a fast resting heart rate should always be addressed by a doctor. People experiencing tachycardia may feel dizzy, nauseated or short of breath. In some cases, tachycardia can lead to a heart attack.
An unhealthy BMI might be an important red flag, but waist-hip ratio, blood pressure readings and resting heart rate are far more reliable health indicators. Stay on top of these readings to stay on track with your health. Early intervention now could save you from serious complications later.