Underweight Health Risks: Causes, Symptoms and Treatment
Although underweight is not as common as overweight in the industrialized nations, it can also be dangerous. You should know that about it!
Underweight: What is that actually?
Officially you are underweight if your BMI ( body mass index) is below 18.5. However, the BMI is considered outdated – various individual factors also play a role in determining whether one is still within the normal weight range.
Underweight or malnutrition?
Even if both terms sound similar at first – underweight and malnutrition are two different things. Malnutrition (also known as malnourishment) is always accompanied by deficiency symptoms, which do not necessarily occur when you are underweight. In the primary form of malnutrition, the affected person does not have enough food with all the necessary nutrients at his or her disposal, while in the secondary form, instead of nutrition, diseases or medication are considered the trigger.
Symptoms: What happens if the body weight is too low?
If deficiency symptoms (mild or severe) do occur in affected people, they can have the following effects on the body:
- Metabolism is slowed down
- Disturbed fluid balance
- Low blood pressure
- Muscle loss
- Hair breakage
- Constant shivering
- Menstruation can be absent
- Osteoporosis can develop (and fatally often goes unnoticed for a long time)
- Muscle function is impaired
- Wound healing slows down
- Susceptibility to infections is increasing
- Diseases tend to be more complicated and last longer
- Life expectancy declines
Causes of underweight
In the industrialised nations, too low a body weight is mostly due to illness and less often directly to nutrition. The following causes can be considered:
- Insufficient nutrient intake (e.g. due to malnutrition, loss of appetite or injury)
- Food is not properly utilized (e.g. due to chronic diseases such as Crohn’s disease or hyperthyroidism, parasites or lack of nutrient splitting in the intestine)
- Generally increased degradation metabolism (e.g. caused by an infection)
- Idiopathic anorexia (“anorexia without apparent causes”, often hereditary)
- Increased age (senior citizens suffer more frequently from loss of appetite or physical or mental limitations)
- High calorie consumption
Treatment: What helps against underweight?
The weight should be slowly brought back to a normal level through healthy eating. The best way to do this is to first calculate your own basal metabolic rate (the calories your body needs to function) and your performance metabolic rate (additional consumption, for example through exercise). Taken together, these two factors add up to the total metabolic rate. In order to gain weight in a healthy way, you should consume about 500 calories more per day than you consume. Depending on the cause of the complaints, some people also need psychological support.
Further help: The BMI calculator
You’re not sure if your weight is in the normal range? You can find more information in BMI calculator!