Underweight: definition, causes and consequences

Last update on December 21st, 2017 by Alicia in category: Weight

Most would be happy to lose a few pounds. Others absolutely want to gain weight and have to pay close attention to what and how much they eat in order not to become even thinner.

Not just overweight, too underweight can bring a lot of suffering. While some struggle unsuccessfully with starvation diets and crash diets, others have exactly the opposite problem: they just don’t eat and gain weight.

Content of the article

Gaining weight can be as difficult as losing weight. Most of the time comes across this apparent "Luxury problem" for lack of understanding. Statements like "I would like to have your problems"Or"Just eat something“As an underweight you can often hear it. Helpful they are mostly not – on the contrary.

The degree between "slim" and "thin" is extremely narrow. The term "slim" is used according to Duden "Well proportioned and narrow at the same time" circumscribed while "thin" with "Lean, lean" is equated.

Although underweight women in particular correspond to the current ideal of beauty in the fashion world, in real life they are often considered to be sick and unstable.

Those who are too thin may actually risk it health problems. Some underweight people get sick faster and are less resilient than people with normal weight. However, being underweight does not necessarily indicate a disease.

But when does one actually speak of underweight? What health consequences can an excessively low body weight have? And what can you do about underweight in terms of nutrition and exercise??

The first part of the two-part series of articles is intended to begin with educate on the subject of underweight and address the definition according to the BMI, possible causes, risks and consequences of low body weight. The next part will then show how to use the right diet and exercise gain healthy can.

When does one speak of underweight?

According to the definition of the World Health Organization (WHO) one speaks to one body-Mass index (BMI) of under 18.5 of underweight.

The BMI describes the relationship between body height and body weight and specifies “scope” in which the weight can move depending on one’s physical disposition. The BMI formula is:

BMI = body weight (in kg) / height (in m) ²

If the calculated BMI is below 18.5, one speaks of being underweight. The underweight is pronounced for a BMI below 17.5.

Light underweight Sometimes it is easy to make a predisposition, as long as the body receives all the important nutrients it needs from food. However, many sufferers want to gain weight in order to feel more comfortable and stronger in their bodies.

On the other hand, underweight or severe weight loss can also be caused by a Eating disorder or other causes arise.

Underweight = eating disorder?

In particular, thin women are under general suspicion, being anorexic or vomiting after every meal.

The suspicion of an eating disorder is not always absurd, but it also discriminates against those who are healthy and eat quite normally. The Pressure to justify can be very stressful for those affected in the long term.

Strong underweight is a criterion for anorexia (anorexia), but underweight or a low BMI is required do not necessarily indicate an eating disorder. Underweight can also have organic causes.

For the diagnosis of anorexia, in addition to a clear underweight, much more information is required. These include e.g. feeding only tiny amounts of food, possibly taking an additional appetite suppressant, laxative or drainage agent, misperception (feel too fat when they are not), increasing fear, denying your own needs and strict self-control.

In addition, the characteristics of eating disorders are not limited to weight. In addition to anorexia, there are also other eating disorders, such as Bulimia nervosa (Bulimia) or Eating fits without weight-regulating countermeasures (binge eating disorder), where the BMI is not a meaningful indicator.

An eating disorder is not always apparent at first glance. Affected people can be extremely lean, of normal weight or extremely overweight. Just like overweight people, underweight people do not have to be eating disorders automatically.

Tip: Instead of immediately putting thin people in a drawer, you can also address them directly to an eating disorder. Those who are affected prefer that rather than being labeled as eating disorders from the start.

Eating disorders are just one, but of many possible causes of low body weight. But what other causes could still be behind underweight?

Causes of underweight

First of all, between Underweight and malnutrition be differentiated.

Malnutrition is also considered "Quantitative malnutrition" denotes and describes the state when the body is supplied with less energy and nutrients than it consumes.

The result: there is one negative energy balance (Power consumption > Energy intake). The body is forced to go to its reserves, i.e. fat and muscle mass, the body weight drops.

In addition to eating disorders, there may also be other influencing factors as the cause of malnutrition or. insufficient nutrient intake give. While many at stress Doing frustrations in the job or in the family, others lose their appetite if they are very tight. Some even forget to eat and continue to lose weight.

anorexia can also occur as a side effect of radiation therapy, medication or medication, painful conditions or poisoning.

One too strict diet and overly healthy eating can lead to deficiency symptoms and underweight. Who e.g. Categorically whole food groups, such as sugar, carbohydrates and fat, are banned from their diet and risk consuming too few calories a day to provide the body with sufficient nutrients. Such malnutrition can also occur with Fast or performance-related increased energy and nutrient requirements (e.g. through sport).

Illness-related malnutrition can include with cancer, occlusions in the gastrointestinal tract, refraining from eating after surgery, chronic inflammation in the mouth, throat or jaw area, as well as through injuries or narrowing in the head area.

Is underweight, however not equate to malnutrition, but can also arise with a sufficient, normal diet. A possible cause are nutrient loss, e.g. may arise as a result of inadequate food utilization.

The reasons for the poor utilization of the ingested food include the too weak breakdown of nutrients in the stomach, the reduced absorption of nutrients in the intestine, biliary congestion, inflammatory bowel diseases (e.g. Chron’s disease), HIV, radiation therapy, pharmacotherapy (drug treatment) or parasites are conceivable.

Also hereditary enzyme disorders, such as lactose intolerance or metabolic disorders like one Hyperthyroidism can be the cause of inadequate utilization of food.

Another cause of underweight due to nutrient loss is the so-called. enteral Protein losing enteropathy to call. This includes the excessive loss of plasma proteins in the intestine. As a result, there is a reduced amount of plasma protein in the blood, which can lead to edema (water retention in the tissues), muscle breakdown and unwanted weight loss.

Causes for the pronounced loss of protein can include the reduced formation of protein in the body, disorders of the small intestine, gastrointestinal disorders or kidney and liver diseases.

Underweight can also go through increased catablolism (Breakdown of metabolic products) that can arise as a result of an increased nutrient requirement. Possible causes of increased catabolism are e.g. Metabolic disorders, infections or some medication.

If diseases can be excluded as a cause, this is also one "Idiopathic Anorexia" conceivable, anorexia with no apparent causes. There is an inherited anomaly in which, despite an increased energy supply, it is usually not possible to achieve any significant weight gain.

Underweight – what to do?

The causes of underweight are thus complex and less easy to treat. Underweight does not necessarily have to, but it can indicate an illness. As long as there are no symptoms of deficiency, even a BMI under 18.5 does not have to be accompanied by health-threatening symptoms and consequences.

Nevertheless: Anyone who is underweight for a longer period of time or who is losing weight despite a normal diet should see a doctor. It is important to clarify that organic or functional disorders, chronic illnesses, eating disorders, depression etc. can be excluded as the cause. In particular, very strong obesity has a negative impact on health and can even be life-threatening.

Only a doctor can determine whether you are seriously ill or simply a poor “feed utilizer”. Often, however, the reason for a low body weight lies in the genes. Whose family circle includes large, petite and slim relatives could also do that Predisposed to a slow metabolism to have.

While good feeders store most of the energy they consume with food as fat in their bodies, bad feeders can eat whatever they want without gaining weight. The ingested food, especially carbohydrates, is poorly utilized, so that little of the ingested nutrients get stuck on the ribs.

Underweight people who are otherwise healthy can get one dietary changes help to put a few extra kilos on the scales. Because a pronounced underweight with a BMI below 17.5 is in the critical area and can health consequences to have.

What are the consequences of being underweight??

Underweight can with various Symptoms and discomfort accompanied. Malnutrition, which is characterized by a loss of fat and muscle tissue, weakens the body and leads to one Undersupply of essential nutrients and trace elements. This can lead to deficiency symptoms.

An undersupply of nutrients affects the water and electrolyte balance. Especially in connection with bulimia eating disorder can be massive Electrolyte disturbance (especially potassium deficiency). However, a lack of calcium, magnesium, iron, phosphate and chloride can also occur as a result.

With anorexia, the low weight can also disrupt the fluid and mineral balance, as well as Impair heart function and dangerously lower blood pressure. These factors can life threatening his.

Being underweight as a result of permanent malnutrition can also disrupt bone metabolism and the development of Favor osteoporosis. Even young people can contract bone loss without first feeling it. However, the consequences (e.g. spontaneous fractures) are fatal and irreversible. With particularly strong underweight can even heart and other Organs damaged what can be fatal in serious cases.

Other serious health disorders are cardiovascular and hormonal changes that affect women in the No menstrual period and consequently can lead to reduced fertility (unfulfilled desire to have children). Pregnant women who are underweight are at increased risk of underweight and slimy newborns.

The risks and consequences of being underweight should not be underestimated. The body is in one permanent state of emergency, have few reserves in the immune system and nerves. The body reaches its limits faster.

In addition to reduced performance and impaired muscle function, underweight people are more susceptible to disease and have an increased risk of complications during the course of the disease. Slower recovery, poor wound healing, and reduced life expectancy are other possible consequences of being underweight.

Many underweight feel very weak and weak in the event of illness or in acute phases of stress. Especially when you can not eat enough, it becomes critical because the pounds fall even further. Many believe that they will be physically better off if they more reserves on the ribs had.

Affected people have to be careful not to get any lighter. But gaining weight isn’t as easy as it sounds.

Underweight: gain healthy

Similar to how overweight people want to lose weight as quickly as possible, underweight people have only one goal: To gain weight as quickly as possible.

But just as radical diets and fasting cures are usually only crowned with short-term success, it does not help if you are underweight French fries, currywurst, chocolate and cola cramming. This strategy will not lead to the longed-for extra pounds in the long run, but much more likely to lead to poor blood sugar levels.

Those who lead under their underweight should not try to cramp up their body weight within a very short time. This is not possible in a healthy way.

First of all, you should accept that you are thin. This insight takes some pressure off and protects against excessive expectations. And that’s important because successful weight gain requires one realistic objective, a lot of Patience and discipline.

With healthy eating in combination with a effective sports program is a gradual and long-term weight gain most promising. The second part of the article series on the topic of underweight looks at how such a nutritional and sports program can be designed and which nutritional tips should be followed by underweight people.

Book tips:

Diet advisor underweight: Enjoyment allowed: over 60 recipes – savory and sweet, with many nutritional tips for daily life, how to gain healthy weight

Malnutrition and malnutrition: Strategies and recipes: regain strength and gain