According to the National Heart, Lung, and Blood Institute, if your body mass index, or BMI, is a number less than 18.5 you’re considered underweight. Although overweight and obesity puts you at risk for certain chronic diseases, if you’re underweight you’re also at risk for developing certain health problems related to undernutrition. Keeping your body weight within a healthy range will minimize your health risks.
Background
According to the National Heart, Lung, and Blood Institute, a healthy BMI ranges from 18.5 to 24.9. BMIs less than 18.5 are classified as underweight, BMIs 25 to 29.9 are overweight, and BMIs 30 and above are considered obese. The National Heart, Lung, and Blood Institute website provides a BMI calculator to help calculate your BMI based on your height and body weight. Or, you can multiply your body weight in pounds by 703, then divide that number by the square of your height in inches. The Centers for Disease Control and Prevention website provides a BMI percentile calculator, appropriate for children and teenagers.
Undernutrition
Unless you have a health condition that affects your body weight, if you have an underweight BMI, you’re likely not eating enough calories and can suffer from undernutrition. This means, you’re at risk for protein, carbohydrate or fat deficiencies. According to Merck, signs of undernutrition include very low body fat, protruding bones, dry skin and hair, hair loss, fatigue, irritability, weakness, always feeling cold and a weakened immune system. According to the U.S. Department of Agriculture, to maintain a healthy body weight, adult women typically require between 1,600 and 2,400 calories per day, and adult men usually require 2,000 to 3,000 calories per day. You may require fewer calories than this if you’re overweight, and you may require more calories if you’re very active on a regular basis.
Nutrient Deficiencies
If you have an underweight BMI, you may also run the risk of developing vitamin and mineral deficiencies, due to a very low calorie intake. Nutrient deficiencies, such as iron-deficiency anemia, are more common in people who are underweight. Certain nutrient deficiencies can cause fatigue, hair loss and weak, brittle bones.
Implications for Children
According to Nemours Foundation, worldwide, up to 27 percent of children under the age of 5 are underweight. Children can suffer the same effects of undernutrition and nutrient deficiencies as adults. However, children who do not get enough to eat may also suffer from stunted growth and developmental delays.
Member Comments