Overweight adults can still be healthy, but as their weight increases so do the chances of bad health outcomes. Body mass index or BMI is a common weight screening measurement, and knowing more about BMI can help people make decisions about their well-being.
BMI is calculated from a person’s weight and height. In terms of health risk, a normal BMI falls between 18.5 and 24.9, while a BMI of 25 to 29.9 is overweight and a BMI of 30 or above is considered obese. Certain chronic health conditions, including heart disease, high blood pressure, diabetes, and gallstones, are more likely to be diagnosed or are more difficult to manage for people with obesity. Some cancers are also associated with obesity.
Over 40% of Americans are classified as obese, but obese body types are more likely in certain groups. More than 45% of Hispanic and nearly half of Black adults have a BMI in the obese range. Lower-income populations also have a higher prevalence of obesity.
Is BMI a Reliable Measure of Health?
Healthcare providers use BMI as a simple gauge of disease risk in patients. However, it may not be the best predictor of health outcomes. The BMI cutoffs do not account for gender, body composition (where or how much of your body is lean) or age-related physical changes such as loss of muscle mass. In some Asian countries, health risks rise at a lower BMI.
BMI is only one risk factor. High cholesterol or triglycerides, smoking, inactivity, and family history of a chronic illness also raise the odds of developing a medical condition. Multiple risk factors make a diagnosis more likely, but not certain.
Other measures, including waist circumference and waist-to-hip ratio, are more accurate at predicting disease risk. Body fat testing can determine how much of a person’s weight is fat, and not lean muscle mass or vital body tissues. Body fat around the heart and abdomen carries a higher risk of cardiovascular disease, diabetes, and certain cancers than fat on the hips and thighs.
Reducing the Risk of Obesity-Related Illness
A person does not need to lose a large amount of weight to reduce their risk of disease. A mere 10% weight reduction can make a difference in health outcomes.
The following key strategies can help with weight loss:
- Try to lose between 1 and 2 pounds per week. Weight loss beyond that is more likely to come from muscle than fat.
- Reduce calories by 500 to 1,000 calories per day and no more. Excessive calorie reduction can lead to malnutrition or overeating later from hunger.
- Dietary fat contains more calories for their weight than carbohydrates or protein. Everybody needs a moderate amount of fat in their diet, but fruits, vegetables, whole grains, and lean proteins will keep a person full without too many calories.
- Increased physical activity burns calories and helps with weight loss. Exercise boosts energy levels, brain function and mental health. It also reduces the risk of chronic disease. A person not already in an exercise routine should aim for 30 to 45 minutes of moderate activity 3 to 5 days a week to start. Ideally, adults should get at least 30 minutes of exercise 6 or 7 days per week. Simple activities like walking, gardening and moderate strength training will boost metabolism and provide health benefits.
- Modifying behaviors that lead to weight gain, such as mindless overeating, will help create lasting, healthy patterns.
- Aim to get enough sleep. Lack of sleep disrupts the balance of hormones that regulate appetite and fullness,
which can lead to overeating.
Shaming people for their weight and lifestyle habits may cause more harm than good. Weight stigma can lead to further weight gain, depression, eating disorders, decreased self-esteem, and emotional stress. A weight loss conversation with a medical provider should focus on goals and what patients can realistically expect to achieve.
Speak with a physician about any weight-related health concerns. Small amounts of weight loss can have a big impact on your sense of well-being. When implementing a weight loss program, pick simple goals and a prevention routine that is easy to maintain. Small, realistic changes are more likely to stick than overly ambitious ones.