3 Reasons You Can’t Tell Someone’s Health by Looking at Them

Not everyone who is sick “looks” sick.

When you think of someone who “looks healthy,” you might imagine someone with clear skin and shiny hair. They might have impressive muscle definition, or just be generally thin. You might imagine that they eat lots of salad, or that they “count their macros.” Here’s the thing: None of these qualities guarantee that someone is healthy. In fact, you can’t tell someone’s health just by their appearance.

Assuming things about someone’s health has real-life consequences. Often, it creates stereotypes or myths about health, and this can make it hard for people to seek or get appropriate health or treatment.

Why You Can't Tell Someone's Health by Their Appearance

Here are all the reasons you can't tell someone’s health based on how they look.

1. Weight is not a perfect indicator of health.

One way that doctors measure health is with body mass index, or BMI. A higher BMI statistically increases the risk of certain chronic illnesses, including type 2 diabetes and heart disease. However, BMI is a limited measurement of health and does not tell the whole story, so you can't tell someone's health based on their BMI.

For starters, just because you have a BMI in a “healthy” range doesn’t mean you’re healthy. (See reasons #2 and #3.) But more importantly, people with high BMIs may be otherwise in good health. They might commit to a healthy lifestyle, and they might have healthy blood pressure or cholesterol levels.

In other words, measuring your risk of chronic diseases involves much more than a scale or BMI chart.

2. There are many “invisible” illnesses.

You can see a broken leg, red plaques from psoriasis, or hair loss from cancer treatment. It’s easy to see these people are dealing with a health problem.

However, there is a long list of diseases that don’t cause visible symptoms, but that doesn’t make these diseases any less serious. They might look healthy, but suffer from difficult symptoms. This includes pain syndromes, such as migraines, fibromyalgia, or irritable bowel syndrome. It also includes autoimmune diseases, such as:

  • Type 1 diabetes
  • Crohn’s disease
  • Celiac disease
  • Lupus
  • Rheumatoid arthritis
  • Ankylosing spondylitis

These are all examples of serious and chronic diseases that cause pain, fatigue, or damage to the body. They may also affect quality of life, require frequent doctor visits or time-consuming treatments, or hinder someone’s personal or professional goals.

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3. Mental illness isn’t always obvious.

There are stereotypes about what mental illness “looks like.” You might be able to see some evidence, such as weight changes from an eating disorder, or a panic attack from an anxiety disorder.

However, many symptoms of a mental illness are much more subtle. Plus, many people with mental illnesses become skilled at hiding their symptoms—but that doesn’t mean they’re not suffering on the inside. Mental illnesses can make it hard to maintain relationships, jobs, and more. They also increase the risk of suicide ideation.

To make it worse, mental health problems often impact physical health. Chronic stress often leads to unhealthy habits that affect physical health, such as an inactive lifestyle, substance use, or eating “comfort foods.” It can also increase the risk of substance use disorder if drugs or alcohol become a coping mechanism for their emotional pain.

The Dangers of Assuming Someone’s Health

Assuming things about someone’s health can have negative effects. One of the most notable examples is that people who are overweight or obese often face stigma, even by their own doctors. They often feel that whenever they go to their doctor with a problem, they are merely told to lose weight.

This weight stigma can have life-threatening consequences. For example, a patient could go to the doctor with unusual symptoms. Unbeknownst to them, they may be having early symptoms of cancer. When the doctor dismisses them as just needing to “lose weight,” it delays their diagnosis and treatment. That’s devastating since early treatment for cancer often improves treatment outcomes.

On the other hand, people with “invisible” illnesses, including mental illnesses, often feel frustrated when others do not take their diseases seriously. People with migraines, for example, often feel like their friends and family members don’t believe them. Their loved ones might even accuse them of exaggerating their symptoms to get out of things they don’t want to do. It’s “just a headache,” right? (Spoiler alert: It’s more than a headache.)

This invalidation can have a few effects. It can strain relationships, and in some cases, the added stress could trigger disease flares or worsen symptoms. At the very least, it robs the individual of feeling supported, and a strong support system is crucial for managing a chronic disease.

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How to Support Your Loved Ones

Instead of assuming what someone is going through, listen openly to people’s experiences. Have compassion for their health challenges (even if you don’t understand them or can’t see them).

Just as importantly, don’t give health advice to someone you think “looks unhealthy,” especially if they’re not asking for it. There’s a chance they live a healthier life than you do. Even if they don’t, you don’t know this person’s medical history, so it’s best to “mind your business.”

After all, being healthy isn’t about looking healthy. In reality, being healthy is about making healthy choices to the best of your abilities, getting the medical help you need, and nurturing your mental health.