Health problems associated with eating disorders

Health problems associated with eating disorders

This section was written by our Patron Dr Hugh Herzig on behalf of the STEPS Eating Disorders Team at Southmead Hospital in Bristol.

Eating disorders affect people in many ways. With them come emotional symptoms like anxiety, depression, hopelessness and low self esteem. They may bring psychological symptoms such as constant thoughts about food, weight, shape and exercise. They can put strain on relationships and cause physical problems which can lead to serious illness and even death. This webpage provides information about the physical problems that may result from eating disorders.

You are probably feeling uncertain about what to do about your eating disorder. But the fact that you are reading this suggests that you have concerns about your wellbeing. This information aims to help you make up your mind about starting or sticking with treatment, to help you make an informed choice. It may raise questions to discuss with your doctor or therapist. It will help explain why you may need certain blood tests or other investigations. And it may make you feel like running off and never coming back. Such feelings are very common in those with eating disorders and it is important that you share them with your doctor or therapist rather than immediately acting on them. 

By restricting their food intake and often other means too, many people with eating disorders maintain their body weight well below the healthy normal range. We must measure your height and weight to know just how far below this range you are and to work out your Body Mass Index (BMI).

The body will react to this state of semi-starvation in various ways. Most problems can be resolved, but only with adequate food intake and restoring a healthy body weight. Nutritional supplements such as vitamin tablets can never make up for inadequate food intake.

Low body weight may lead to slowing of the heart rate and low blood pressure. You may feel tired, faint, dizzy or have palpitations. You will feel cold even in warm surroundings.

As well as listening to your heart and checking blood pressure, your doctor may need you to have an ECG (electrocardiograph), which gives more information about heart function. This slowing of the heart can be dangerous and you may need to see a heart specialist for further investigation.

At lowered body weight the normal sex hormones stop being produced. This results in irregular or absent menstrual periods and infertility. Growth is delayed in children and adolescents. Men may experience impotence.

Low body weight and absent menstrual periods can lead to Osteoporosis, a softening of the bones that is usually seen only in older adults.

At very low body weight, people feel weak. Simple day-to-day activities become harder, like walking fast or climbing stairs. This is due to the thinning and weakening of muscles. Your doctor or therapist may check how easily you can stand up from sitting or squatting to give an indication of muscle power. Muscle weakening brings a risk of sudden collapse. Should you faint or collapse, you should seek urgent medical attention from your GP or at a hospital Accident and Emergency department.

Inadequate food intake effects the stomach and bowels. The little amount of food and fluid passing through the body results in constipation. Even small quantities of food may leave one feeling bloated and uncomfortable.

Food restriction and low body weight may bring about changes in your skin, which becomes dry and may develop fine downy hair. Your hair too may become thin and dry.

Some people with low body weight develop oedema (fluid retention usually in the ankles leading to swelling and puffiness). The excess fluid may disguise the true extent of loss of body mass.

Many people with eating disorders make themselves vomit. This can become frequent and habitual, and difficult to change. Sometimes people describe it as having become an almost automatic reflex after eating.

As well as getting rid of food and controlling body weight, vomiting may come to be a means of dealing with distressing feelings or be a kind of self-punishment. With binge eating it may form a vicious circle, each problem reinforcing the other and making change harder.

Many people are surprised to learn that in fact vomiting after eating is not a good method of getting rid of food. When the stomach suddenly contracts to vomit, around 50% of its contents is pushed further down into the intestine where it will be digested and absorbed. Only half the food is expelled.

But while half of the food contents of the stomach stays in the body, vomiting does cause a great loss of certain essential minerals. The habit of attempting to wash out all stomach contents by repeatedly drinking water and vomiting hastens this mineral loss. These minerals make up the acidic stomach fluid important for the breakdown and digestion of food.

The most important mineral to be depleted by repeated vomiting is potassium, but there are others too. These include phosphate, calcium, zinc and magnesium.

Potassium is vital to life because of its role in nerve conduction, particularly the nerves and muscles of the heart. So when potassium levels in the body fall, the heart may lose its regular beating rhythm. This may cause faintness or even loss of consciousness. Occasionally the heart may stop beating altogether.

Your doctor or therapist may check the potassium level with a blood test and the heart rhythm with an ECG (electrocardiograph). You may be prescribed potassium tablets or need admission to a medical ward, where intravenous drip potassium replacement can be given safely.

Of course these measures won't help for long if the frequent vomiting continues. The only lasting way to maintain normal safe potassium levels is to reduce and ultimately stop vomiting.

Repeated vomiting, laxative misuse, and misuse of diuretics (water tablets) all lead to significant mineral and fluid loss, including potassium. In combination, these behaviours are particularly risky.

In addition to the dangerous effect on the heart, repeated vomiting commonly leads to other health problems. Low potassium can in time lead to kidney disease. Frequent vomiting is likely to cause dehydration, bringing faintness, tiredness and headache.

Acidic stomach fluid in the mouth erodes dental enamel and sometimes it is the dentist who first notices and asks about the problem of frequent habitual vomiting. Dentists advise against brushing teeth straight after vomiting, as this worsens the acid damage. Rinsing is recommended.

In reaction to frequent vomiting, the saliva glands in the cheeks may enlarge, giving the face a swollen appearance. And frequent vomiting also results in damage and bleeding of the gullet, which may cause pain, blood loss and anaemia.

Laxative medications include

  • Senokot
  • Movicol
  • Lactulose
  • Dulco-lax
  • Docusol
  • Fybogel

and many other brands. Most are available over the counter without prescription.

Laxative misuse is a method people may use to try to get rid of food and reduce their body weight. Misuse of a medication means taking it when it is not clinically helpful to do so, or taking it in an excessive dose. Everyone knows that laxative medication is for constipation. And it is true that some people with eating disorders complain of constipation, bloating or discomfort. However, when the bowel slows down because of insufficient food and fluid intake, or because stomach contents are being repeatedly vomited, taking laxatives won't help.

The bowel needs enough food and fluid within it to be able to push the contents along and keep regular. Some people with eating disorders take large quantities of laxatives in an attempt to get rid of food and lose weight. They may observe their weight has decreased when they get on the scales after laxative misuse and subsequent diarrhoea. But any such weight loss is due entirely to a loss of body fluid (water and minerals). There is no loss of body tissue mass, fat, protein or calories. Such laxative misuse causes dehydration, bringing faintness, tiredness and headache. It can also cause severe depletion of essential minerals, which are present in the fluid within the bowel.

Laxative misuse will in time disturb the body's fluid balance, and some people who take excessive laxatives develop oedema (fluid retention usually in the ankles leading to swelling and puffiness). The excess fluid may disguise the true extent of loss of body mass.

Many laxatives work by stimulating the muscle wall of the bowels, which contract and push the contents through quicker. But such artificial stimulation eventually leads to loss of bowel tone, the muscle wall becoming thinned and flaccid. At this stage bowel function may be permanently weakened and slow and even the presence of adequate food and fluid cannot restore it to normal. Many people end up suffering severe and long term constipation, which will not respond to more laxative medication.

At low weight, the body's normal hormones stop being produced. In a woman menstrual periods become irregular or stop altogether and she becomes infertile. In children and adolescents, the changes of puberty cannot occur without sex hormones and growth may be permanently stunted. In men, sexual function may be disturbed, leading to impotence.

Prolonged low body weight and sex hormone deficiency bring serious consequences. As in older women after the menopause who no longer produce oestrogen, low weight patients have an ever-increasing risk of osteoporosis. Hips and vertebrae are especially prone to breaks and the softened bone is hard to fix, sometimes resulting in permanent disability or disfigurement. Whereas most health problems resulting from eating disorders can recover quickly, osteoporosis may remain long after eating is resumed and healthy body weight restored. Hormone replacement therapy or the contraceptive pill doesn't seem to help either. If you have had low body weight and no menstrual periods for a long time, your doctor or therapist may recommend you have a bone scan (DEXA scan) to check for osteoporosis.

On recovery from eating disorder, when you are again eating enough food and maintaining a healthy body weight, it may take some months for regular menstrual periods to return. If after some time your periods do not resume normally, consult your doctor. Absent or irregular periods are no guarantee against getting pregnant. You should take precautions to avoid an unwanted pregnancy.

This webpage aims to provide you with information that is important to you, not to worry or upset you. Remember, most people with eating disorders do recover, and most can benefit from treatment. Even though you may feel completely stuck, you too have the chance to change and get better.

  • physical changes
  • weight loss
  • increased sensitivity to cold
  • hypersensitivity to noise and light
  • sleep disturbances 
  • poor circulation
  • gastro-intestinal discomfort
  • changes in hair texture and skin tone
  • general tiredness
  • muscle weakness
  • unstable mood 
  • emotional and tearful
  • increasing anxiety
  • increasing irritability 
  • loss of sense of humour
  • apathy
  • preoccupation with food and meal planning
  • changes in diet and meal pattern
  • reduced interest in, or avoidance of, social events
  • cognitive changes
  • reduced concentration
  • impaired judgment
  • memory loss

© Dr Hugh Herzig

Below you can download a resource developed by SWEDA that focuses on eating disorders and their affect on oral health.

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