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Underweight or Malnourished

Lots of people believe dietitians mostly see people for weight loss. This is fundamentally not the case. In fact, our clients come for a wide variety of reasons. A fair number actually see us for weight gain. Did you know, statistically, nearly 400,000 Australian adults are underweight? There are many reasons people become underweight or malnourished. These can include some disease processes such as cancer, lung or heart disease, some surgeries such as gastrectomy, the ageing process, eating disorders or orthorexia which is an obsession with eating in a “healthy” way. Put simply, being underweight is a massive health risk and has been linked to increased infections, falls, long hospital admissions, social isolation and poor mental health.

Underweight or Malnourished, Is There A Difference?

You can be malnourished without being underweight. In other words, you can still be within a healthy weight range or may be overweight, but you’re not eating enough to meet your body’s nutritional needs. This could be because your food intake might be lower than it should be or because your body needs more nutrition. One example might be if someone is unwell or has aggressive treatment for something like cancer.

Another scenario could be if you’ve lost a dramatic amount of weight in a short period of time, however, are still “technically” classified as in the healthy weight range. As an aside, this is just one of many reasons why the BMI (Body Mass Index) is not necessarily the best measure of health.

But Isn’t Thinner Better?

The simple answer is NO. While our society certainly glamorises the “thin ideal”, being too small is very dangerous. Being too small increases your risk of falls and fractures, infections, osteoporosis (weak bones), as well as complications following surgeries. Being too small affects fertility in women and increases your likelihood of anaemia. Anaemia is caused by low iron levels and can lead to increased fatigue.

In younger adolescents and young adults being underweight or malnourished can directly impact your mental health, and increase the risk of anxiety and depression, self-criticism and social isolation. In older adults, it’s been shown to increase Alzheimer’s disease, dementia and the need for aged care.

Many people, including some doctors, don’t realise that our healthy weight range increases after the age of 65 (by 5kg on average). We have a lot of clients who don’t understand this and continue to strive for lower body weight, without realising this can be dangerous to their health. Especially (though not exclusively) as they continue to age.

So, If I’m Underweight Or Malnourished Shouldn’t I Just Binge On Fast Food?

This is generally not our strategy at all. It’s quite common that when someone is underweight (for whatever reason) they develop anorexia. The word anorexia means lack of appetite. So exactly what the body needs (to eat more), is not being supported by your body (feelings of hunger).

The term anorexia is not to be confused with anorexia nervosa, an eating disorder. This is a complex psychological disorder manifesting as self-starvation to maintain abnormally low body weight.

Yes, people who are underweight or malnourished need to eat more calories, particularly more protein to replenish the lost stores. The quickest way to do this is to simply eat more. However, it’s not actually that simple for most underweight or malnourished clients. “Eating more” is exactly what they find most difficult.

The easiest way to increase caloric intake is to increase fats throughout the diet. The fat nutrient (different from protein or carbohydrate) is the most concentrated form of energy at 9cal/g of fat (more than carbohydrate and protein at 4cal/g). It’s easily added to food and meals in different ways… Adding more oil when cooking, more margarine to toast or dressing/mayonnaise to vegetables or a salad.

What About My Cholesterol Or Sugars?

Firstly, being underweight and/or malnourished is far more dangerous to your life than your immediate cholesterol or sugar levels. Secondly, you can manage your cholesterol and sugar levels with medications but you can not increase your weight with pills. Thirdly, increasing your weight to get you into a safer range will itself not impact either your cholesterol or your sugar levels.

Pay close attention to these next two sentences:

  1. Eating sugar does not cause diabetes, full stop! Being overweight or obese is linked with diabetes.
  2. Eating sugar in a balanced diet does not cause diabetes.

Repeat those last two sentences if you need to! Being underweight and/or malnourished is DANGEROUS.

It’s important to understand that people see Dietitians for many different reasons. For more information about the kind of diet that’s right for you, get in contact with us.