BMI stands for body mass index, an estimate of your body fat based on your weight and height. It’s a more reliable indicator of body fat than weight alone, because it takes into account your body structure. Knowing your BMI can help you and your doctor determine if you're at a healthy weight.

Generally a body mass index (BMI) between 18.5 and 24.9 is considered healthy. However, if you’re older than 65, it may be better to have a BMI between 25 and 27, rather than under 25. That slightly higher BMI may protect your bones from osteoporosis.

Maintaining a healthy weight, or normal weight, can benefit joints already affected by arthritis. Did you know that 1 pound of weight puts an additional 4 pounds of pressure on knees? You can reduce joint pain by shedding pounds, even as little as 10 percent of your total body weight. Doing so can also decrease your risk of developing arthritis in joints not already affected and lower the chances that you'll need a joint replacement.

Though there are many diets and exercise programs out there, the simplest way to lose weight is to eat less and move more. If you need help getting moving, try the 12-Week Walking Plan or contact your local Arthritis Foundation office and explore our Programs for Better Living, which include land and water exercise classes, tai chi and our proven effective Walk With Ease program.

BMI is frequently used as a indicator for how body weight affects health. A normal-weight BMI reduces risk for a number of health problems, including:

  • High blood pressure 
  • Low good cholesterol or high bad cholesterol
  • Type 2 diabetes
  • Heart disease
  • Stroke

While BMI is useful, it’s just one of many factors that influence your overall health, some experts believe a high percentage of body fat (compared to lean muscle) is a better indicator of health risk. Whether you smoke, your cholesterol, blood sugar and blood pressure levels, your diet and your current level of physical activity all play a role.