When most people think of Anorexia Nervosa, they likely think of those struggling with distorted body image, long-term food restriction and severe weight loss.

While those are prominent symptoms of this complex eating disorder, anorexia can also result in potential medical risks you may not be aware of. Let’s take a look at some of those:

1). Anemia

Anemia is a lack of red blood cells (RBCs) in the bloodstream. RBCs house hemoglobin, a protein that enables RBCs to carry oxygen from the lungs throughout the body, in addition to transporting carbon dioxide back to the lungs to be exhaled. The body requires folic acid, Vitamin B12 and iron (among other things) to produce RBCs, as well as hemoglobin.

A lack of these nutrients, commonly experienced by someone who is restricting food intake, often leads to anemia and inadequate oxygen transport throughout the body. It could also result in fatigue, weakness, pale skin, irregular heartbeat, shortness of breath, dizziness, chest pain and/or headache.

2). Constipation

Constipation generally involves either having difficulty with or the inability to make a bowel movement for an extended period of time. If there is no movement after 3-4 days, medical intervention is recommended.

People struggling with anorexia more frequently deal with constipation because of inadequate food and fluid intake that can cause decreased gastric motility (ability to move freely). This means that the intestines struggle to properly push food through the digestive system and produce a bowel movement. Those experiencing constipation likely feel an uncomfortable bloat or feeling of extreme fullness.
Initial treatment for constipation includes natural laxatives (prune juice, bananas, apples, melons, avocados, leafy green vegetables, raw seeds and nuts, legumes, etc.) before moving on (as is clinically appropriate) to stronger laxatives like Miralax, Dulcolax, Milk of Magnesia or enemas.

3). Dehydration

Most people might think of dehydration as not taking in enough water, or more specifically, when someone loses more water (through urination, defecation, sweating, vomiting, etc.) than they ingest. While this is true, a large percentage of dietary water also comes from solid foods. When someone restricts their food intake, they become more susceptible to dehydration.

Dehydration can manifest in a number of symptoms including thirst, dark-colored urine, infrequent urination, fatigue, dizziness and confusion. In more serious cases, it can cause a number of secondary complications, such as kidney failure, hypovolemic (low blood volume) shock, electrolyte imbalances and orthostatic hypotension. Treatment of mild dehydration generally begins with adding oral fluids and fortifying the patient’s diet while intravenous (IV) fluid is required in more severe cases.

4). Electrolyte imbalances

Electrolyte imbalances, which are closely linked to dehydration, also commonly result from restricted diets. Electrolytes such as sodium, potassium, calcium and chloride are essential for the body to function properly. If those electrolytes are not sufficiently represented in one’s diet (as is often the case with AN), the levels will dip and the body’s delicate balance will be thrown off.

The most frequent electrolyte imbalances seen in anorexia are hyponatremia (a low concentration of sodium ions in the bloodstream) and hypokalemia (a low concentration of potassium ions). A shortage of sodium in the body can impact brain function, causing nausea and vomiting, confusion, headache, fatigue, irritability, muscle weakness or cramps and seizures. Hypokalemia can impair muscle (especially heart) function, causing muscle weakness and cramping, an irregular heartbeat, abdominal cramping or bloating, thirst and frequent urination.

In addition to a balanced meal plan, electrolyte imbalances can be treated with dietary supplements (e.g. sodium chloride for hyponatremia, K-Dur for hypokalemia). In extreme cases, IV therapy is suggested.

5). Orthostatic hypotension

Another complication of anorexia is orthostatic hypotension (OH), which is a drop in blood pressure when getting up from a laying to sitting position or from a sitting to a standing position.

OH is common in people suffering from anorexia because inadequate food and fluid intake can lead to dehydration which in turn, can cause low blood pressure. If someone is not taking in enough liquids, their overall fluid volume can decrease, resulting in a blood pressure insufficient to push blood to all parts of the body (most notably the brain). When blood pressure drops too much or too rapidly, the patient can experience dizziness or lightheadedness, blurry vision, weakness, confusion, nausea or fainting. Treatment generally includes addressing the underlying cause (usually dehydration in cases of anorexia), mostly with oral or IV fluids.

The medical complications and risk around anorexia don’t stop with these five areas. Others may include low heart rate, osteoporosis, kidney failure, stunted physical growth and more.

If you – or someone close to you – is suffering from anorexia or experiencing any of the symptoms in this blog, don’t be afraid to reach out for help.


Sean Jacquet joined Walden in February 2016 as a Registered Nurse in Walden’s Eating Disorder Residential Program. He received his Bachelor of Arts in Journalism from UMASS Amherst (2003) and started his career with GateHouse Media as a sports staff writer for MetroWest Daily News (Framingham, MA) and Daily News Tribune (Waltham, MA) before going back to school and receiving his Bachelor of Science in Nursing from Massachusetts College of Pharmacy and Health Sciences in Worcester, MA (2012). Prior to joining Walden, he was a staff nurse and a Nursing Supervisor in the Arbour system. He can be reached at sjacquet@waldenbehavioralcare.com.