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By Michelle May, M.D.

Not long after graduating from medical school, I was sitting in a hospital nurses’ station between two other residents, writing progress notes and orders on our patients. Suddenly a woman ran out of a patient’s room and over to the desk where we were sitting. She came right up to me and said, “Hurry! It’s an emergency!” As I stood up to help, she added, “My father needs a bed pan!” The other residents chuckled as I went in search of the urgently needed item, having no idea where to begin to look. I located a nurse to help her and returned to my work.

I have the highest respect for nurses so I wasn’t offended, but I found it telling that the daughter made an assumption based on a single external attribute: we were all in our twenties, all working on charts, all wearing scrubs with white coats, and all had stethoscopes around our necks, but I was the only woman. I told the other residents that perhaps she didn’t assume that I was a nurse who actually knew something, but perhaps she assumed that as a female, I would be the most friendly and helpful, and therefore, she was right!

While that story has brought many laughs at cocktail parties, it is a good example of an outdated assumption that led to a misdiagnosis and a brief delay in addressing her father’s problem. Any time we make assumptions about a person based on a single attribute, especially an external one, we are likely to make mistakes. You know the old saying: When you assume, you make an …

There is extensive data about the bias, prejudice, and discrimination that occur on the basis of a person’s size and the harm that causes. As destructive as it may be, this form of stigma, when called out, will be judged harshly by rational, fair people. However, it is the hidden assumptions by my generally well-meaning colleagues in the medical and wellness fields that I want to address here.

The erroneous assumption that thin equals healthy and fat equals unhealthy is still deeply entrenched in healthcare despite numerous studies, books, articles, and experts challenging the scientific basis of those assumptions. On the basis of a patient’s size alone (typically using BMI as their defense), smart, rational people justify their assumptions about that person’s health, risk factors, diet, physical activity, emotional state, compliance, and even character.

Even where correlation exists, it does not prove cause and effect—and certainly doesn’t accurately predict an individual’s behaviors or health. It is disrespectful, lazy, and even dangerous to assume one knows anything about a patient’s health, risk factors, or choices without taking a thorough history, performing a skilled physical exam, and ordering necessary labs and diagnostic studies. It is tantamount to guessing.

At best, these assumptions are a shortcut that damages the patient-clinician relationship. At worst, it is discrimination that has potentially serious medical consequences. Here just a few examples of errors made as a result of size assumptions.

  1. A medical assistant compliments a teenager on her weight loss. The teen has been restricting and purging.
  2. A 47 year old woman is told by her doctor that she needs to go on a diet and start exercising to lose some weight. The doctor neglected to ask her patient about her diet and exercise patterns. If she had, she would have known that her patient was vegan and had run five half marathons in the past two years.
  3. A 29 year old male with a BMI of 22 is complimented on his apparent good health. The doctor neglected to ask questions about his diet and exercise patterns. If he had, he would have discovered that his patient eats fast food eight to ten times a week, spends six or more hours a day playing video games and watching TV, and never exercises.
  4. A male with a BMI of 33 and a strong family history of premature cardiovascular disease is diagnosed with hypertension and is told to lose weight. He is not offered antihypertensives for over eight months despite persistently elevated blood pressure.
  5. A 27 year old obese woman comes into the emergency room with severe abdominal pain and delivers an infant into the toilet during the urine collection. She had been diagnosed with polycystic ovarian syndrome but a pregnancy test was not ordered on follow-up office visits despite continued amenorrhea.
  6. A woman being seen for an upper respiratory infection is lectured about her weight.
  7. A 62 year old male with severe knee pain and limited mobility due to osteoarthritis is told that he must lose 50 pounds before he will be considered for knee replacement surgery.
  8. Patients with a BMI over 25 are advised to lose weight—despite lack of evidence for the long term effectiveness of dieting. When unsuccessful at either losing weight or maintaining weight loss, the patients are perceived as non-compliant.

Sadly, there are many other examples of medical care that is adversely affected by size assumptions. (Please feel free to share your stories in the comments section below). While some of these examples are just bad medicine, these mistakes can be avoided if the clinician adopts the Health at Every Size® principles.  It boils down to the clinician asking themselves, “If I eliminated all of my assumptions based on this patient’s size, what would the appropriate questions, exam, diagnostic studies, recommendations, and treatment be?”

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