A natural thin-build is OK, and if you maintain a healthy diet and exercise regularly – it’s not a health concern. However, when your body mass index is below 18.5, it’s time to seek some help.
“A lot of people feel that being overweight is a high risk,” said Kristene Schulte, a Marshfield Clinic registered dietitian. “Being underweight, however, can be a health risk as well.”
Potential health problems
Your risk of infection and other medical conditions, like osteoporosis, anemia and heart disease, can increase if you are truly underweight. Infection risk also can increase because your immune system may be weaker. Additionally, losing too much weight can lead to severe muscle loss.
“Some people even have hair loss, and it also can disrupt your hormone regulation,” Schulte said.
For women who are underweight, amenorrhea, which is the absence of menstrual periods, and pregnancy risks, like low fertility, miscarriage and stillborn pregnancy, are other health concerns. Schulte added that because hormones change when you are underweight, women also are likely to begin menopause early.
“It’s normal to have a little adipose tissue or body fat,” she said. “We need that to absorb fat-soluble vitamins A, D, E and K. Adipose tissue also helps with maintaining a healthy hormone balance.”
As you age, health risks associated with being underweight increase and your body loses muscle mass with every decade. Being over age 60 and underweight can compromise your immune system, lead to bone fractures and decrease chances of survival when faced with diseases or illnesses.
Safe ways to promote weight-gain
To safely put on weight, it’s important to have a healthy balanced diet with nutrient dense foods. Rather than adding simple sugars and junk food to fill you up, focus on healthy fats and a nutrient-rich diet. Schulte recommends three meals a day with two-to-three healthy snacks in between. If your appetite is poor, focus on trying to eat six mini-meals to keep from getting overwhelmed.
A few healthy calorie-dense or high protein options to include are whole milk, cheese, yogurt, eggs, nut butters, nuts, sunflower or pumpkin seeds, beans, avocadoes and peas. Schulte says instead of making oatmeal with water, you can add milk to provide more protein.
“I encourage people to focus on choosing healthy whole foods first, but sometimes people are just so weak they may need a liquid meal replacer that’s easier to swallow or take in if they have a poor appetite or difficulty chewing,” Schulte said. She suggested options like Ensure®, Boost® and Carnation Instant Breakfast®, or a fruit and Greek yogurt smoothie. “Those options can help boost vitamins, minerals, protein and calories,” she said.
Exercise, too, can stimulate appetite and help build lean muscle mass, said Schulte. She recommends including strength training with bands or light weights.
Know why you’re underweight
If you are feeling weak or losing a lot of weight, it’s important to see your doctor.
He or she can refer you to a dietitian or nutritionist. Some insurance will cover seeing a dietitian to help promote a healthy weight, or other conditions causing weight loss. Schulte said the underlying cause of being underweight is important to know, because stress, depression and other health concerns like uncontrolled diabetes can be factors in weight loss.
“Sometimes it’s a sign of a dietary problem, but it also could be a health problem, like malabsorption,” Schulte said. “It could be a signal that a disease state is either new or getting worse.”
If you have concerns about weight loss or being underweight, talk with your provider.