The media likes to remind us all the time that being overweight and obese is unhealthy, since these are conditions that cause a number of medical issues. But the opposite, where an individual has too low of a BMI and is considered underweight, is just as, if not more, concerning than being overweight. When you are underweight, your body is not getting enough nutrients and vitamins to stay healthy and function properly, and that can lead to impaired functioning and immunity.
But how do you know if you have a low BMI? What can you do if you’re underweight? Keep reading to learn all about low BMIs and the risks involved.
How Do I Know If I’m Underweight?
One way to tell if you weigh less than what is healthy for your body is to go by the body mass index, or BMI. The BMI is considered a decent measure for health since it compares a person’s height to weight. You can find a number of BMI calculators on the internet that are accurate.
The BMI ranges are as follows:
- Underweight: Below 18.5
- Normal Weight: 18.5-24.9
- Overweight: 25.0-29.9
- Obese: 30.0 or Above
There are two instances where BMI may have errors, and that is when an athlete is using BMI, since the body mass index takes no consideration of how much muscle mass a person has. This is why some muscular football players, for example, get an obese BMI reading but are really in perfect health. The second time BMI is inaccurate is with older adults, since they tend to have muscle atrophy, meaning their body fat levels are underestimated.
According to the Centers of Disease Control and Prevention (CDC), anyone who has a BMI below 18.5 is considered underweight. Of course, you need to keep in mind that the BMI is not a snapshot of health. You will need a body fat percent measurement to truly understand how much body fat you have.
You need to also consider any symptoms correlated to being underweight.
Symptoms and Risks of Being Underweight?
If you are truly underweight, you will notice certain signs and symptoms happening. Keep in mind that some of the symptoms that are associated with excessive thinness are also symptoms for other medical conditions or could merely be due to bone structure.
The symptoms of being underweight include:
- Fragile bones
- Hair loss (on the head)
- Skin, hair, and teeth problems
- Irregular menstrual cycles and missed periods
- Infertility – because of a lack of menstruation, women with low BMI also experience anovulation, or a lack of ovulation. Chronic anovulation leads to infertility.
- Weakened immunity
- Poor development and growth in children who are underweight and/or malnourished
Let’s consider the last point for a moment. Apart from the other symptoms, osteoporosis is definitely the one you should be extremely concerned about, especially if you are female and experiencing amenorrhea (abnormal absence of menstruation). Low body weight and a lack of periods has been linked to low bone mineral density (BMD).
Causes of Being Underweight
There are a number of reasons someone could become underweight, and some of the reasons could be compounded. The causes include:
- Family medical history. Sometimes low BMI is hereditary.
- High metabolism. When a person has a high metabolism, they might need more food than they are taking in and this can result in a lack of muscle mass and body fat.
- Physical illnesses or chronic diseases. Whenever someone is nauseous because of a medical condition or disease, they will have trouble eating and gaining weight. Other conditions that decrease appetite, like cancer, diabetes, digestive conditions, and so on will make it difficult to gain weight and keep it on.
- Mental illness. Poor mental wellness will affect appetite and weight as well. People who are depressed, anxious, have obsessive-compulsive disorder, eating disorders, or other mental conditions that affect body image will have difficulty eating and maintaining weight.
- Frequent physical activity and exercise. Athletes who do not eat enough are at risk of becoming underweight, especially females.
If you are underweight and are having trouble determining what the cause may be, it is recommended to make an appointment with your doctor to discuss what may be wrong.
How Can I Get To a Healthy Weight?
The reasons for being underweight will ultimately decide how the condition is treated. First, the person has to be willing to gain weight—which can be difficult if they are dealing with an eating disorder like anorexia, bulimia, or EDNOS. Doctors may recommend that you use a specific diet or limit your physical activity. You might be assigned a dietitian to learn how to put together more nutritious meals.
Here are some tips to help with returning to a healthy weight:
- Eat smaller meals more frequently. If you are having trouble eating bigger meals on a 3-meal schedule, then you might have more success with smaller meals spaced more frequently throughout the day. This will help you eat more over time.
- Add snacks. Complex carbohydrates and high-protein snacks are ideal if you want to gain weight. Think about snacking on roasted nuts, trail mix, protein bars, pita chips with hummus, peanut butter and apple slices, and similar options.
- Avoid eating empty calories. One thing you want to avoid is junk food and ultra-processed foods that are devoid of nutrition, since most of the chemicals can have an adverse affect on your already weakened body.
- Try adding calorie-dense foods. Think about what you usually eat and how you can add some extra calories to those meals. For example, if you have oatmeal for breakfast, you could add in ground flaxseed or chia seeds for extra calories. You might mix some protein powder into your smoothie. Put some granola in your yogurt. Add a few more slices of avocado to your sandwich. Every little bit counts.
Conclusion on Low BMI
Overall, if you believe you are underweight, it is not the end of the world. Since you are aware of the problem, you can begin making the correct steps towards returning to a healthier weight. Since you don’t want to develop any complications, such as infertility or hair loss, contact a doctor and start eating more calories. From there, work towards maintaining that healthy weight.