Many people struggle with body weight during their lifetime. Because of the natural tendencies of the prosperous, the majority struggle to lose weight, so there is a lot of emphasis on weight loss programs. There tends to be less public attention to people with the opposite issue of being underweight, however, which may make it difficult to come forward with this problem. Being underweight is also poses significant health risks that should be taken seriously.
What is Considered Underweight?
The body mass index (BMI) is a statistical standard through which doctors consider whether you are at a healthy weight for your height. At the heart of it, our bodies are designed to carry a certain amount of weight to promote healthy muscle and organ function, and going too far above or below this height/weight ratio can put a person at risk for health problems. The formula for BMI is a person's weight (in pounds) multiplied by 703, and then divided by the total height squared (as measured in inches). For people with "normal" weights, the average BMI calculation is 18.5-25. Anything below this is considered underweight. A BMI measurement less than 16.5 denotes that a person is severely underweight, posing risks for malnutrition, starvation, and other health complications.
Risks of Being Underweight
Independent of the underlying causes behind low weight, a very low BMI can have serious health consequences. People that are underweight tend to be very tired and prone to exhaustion. The lack of nutrients can also deplete the immune system, making a person much more susceptible to illnesses and infections. Low iron intake can lead to anemia, as state where less oxygen is carried in the blood, furthering their feelings of exhaustion and reducing organ function. (Please see our article on Anemia for more information.) The severely underweight may additionally develop hair loss or osteoporosis, even if they are quite young.
Causes of Being Underweight
Active young people, for example, may find that despite reasonably high caloric intake, they are able to remain thin. For them, weight gain is a concentrated effort, perhaps desired to increase physical performance in sports (through increased muscle mass) or enhance feelings of sensuality (some thin women wish for curvier bodies, for example). Over training, particularly for endurance sports (like long distance running) can cause a person to burn far more energy than put into the body, resulting in low body weight.
Eating disorders, such as anorexia and bulimia, severely limit nutrient uptake by the body, resulting in very low BMI. Each of these conditions is characterized by low body weight, which is due to the purposeful restriction of the amount of food eaten or absorbed (by vomiting before digestion). Digestive disorders or inflammatory bowel diseases (such as Crohn's disease) can also severely limit nutrient uptake in the gastrointestinal system, causing weight loss. Cancer, cancer therapies, tuberculosis, and HIV/AIDS may also lead to very low body weight.
While type II diabetes is typically associated with obesity, excessive weight loss might be a sign of type I diabetes. In this form of diabetes (sometimes called "juvenile" or "childhood" diabetes, given the early onset), sugar builds up in the blood because there is no insulin from the pancreas to help bring these nutrients to the cells. As the body tries to cleanse the sugar from the body through the urine, it also releases a lot of Hyperthyroidism is a hormonal imbalance caused by an overactive thyroid gland. The thyroid orchestrates many aspects of the body's metabolism, so can easily push everything into overdrive if not controlled. People with hyperthyroidism usually have tremendous appetites, but despite the calories they consume, they are unable to gain weight.
Conventional Weight Gain Therapies
Conventional therapies for weight gain largely depend on the cause of the weight loss. Certainly, if some sort of physical illness, such as a thyroid disorder or diabetes can be identified, treatment of these conditions can help restore the lost weight. For others, the most direct solution is increase in calorie intake. To help begin restoring nutrients to very thin people, very high calorie, vitamin-packed nutritional supplements are often given to revitalize the body. If there is a psychological disorder behind the weight loss, such as anorexia or bulimia, addition counseling may also help greatly in the quest to reach a healthier weight.