10 Signs Someone Is Hiding a Mental Illness

by Nicola P. Young about a year ago in list

If you can recognize the signs someone is hiding a mental illness, you'll be better able to help them.

10 Signs Someone Is Hiding a Mental Illness
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Especially in teenagers and young adults, it can be hard to recognize what behaviors are a normal part of growing up, and what behaviors may be signs someone is hiding a mental illness. There are many different mental illnesses out there that people can suffer from. These illnesses will also manifest themselves in different ways in each individual. But understanding these common symptoms and different ways that mental health issues may appear can put you in a position to change, or even save, a friend or family member's life.

Social Seclusion

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Social seclusion may be a sign someone is hiding a mental illness for multiple reasons: first, someone struggling with a mood disorder, depression or anxiety, or any range of other mental health problems may want to distance themselves so that others don't notice other behavioral and mood changes, or have to reveal their true feelings. But more significantly, social seclusion is one of the most common symptoms of depression, and of all of these disorders, as someone who suffers from depression and other mental illnesses may often find it hard to feel motivated to interact with others, or struggle to feel connected to the world, even to people they love.


If a friend or family member seems suddenly irrationally irritable, it may be a sign someone is hiding a mental illness. Many people believe that manic or hypomanic phases of bipolar disorder always come with feelings of euphoria, reckless behavior, substance abuse, etc. And that is certainly often the case. However, it may also appear as simple unexplained irritability. Similarly, irritability is a very common symptom of depression and anxiety. So if someone you know seems highly irritable, with no apparent cause, it could be a sign that they are suffering from a mental illness.

Sudden Changes in Weight or Appetite

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Sudden changes in weight or appetite may be a primary symptom of some mental illnesses. Most obviously, these changes could be a sign of an eating disorder, such as anorexia or binge eating disorder. However, healthy eating habits may also be disturbed by other mental illnesses, including depression and anxiety. For some, depression brings a loss of appetite and subsequent weight loss. For others, stress and emotional eating may lead to sudden weight gain. Furthermore, depression is robustly linked to low self-esteem, and so may trigger the onset of an eating disorder, even in someone who previously had no history of it. While everyone's eating habits fluctuate now and again, sudden, drastic changes in appetite or weight are one of the most significant signs someone is hiding a mental illness.

Low Self-Esteem

As just mentioned, depression, anxiety, and other mood or personality disorders can cause low self-esteem. This symptom can manifest itself in many different ways. Disruptions in eating habits, especially eating disorders, is one such way. But general self-criticism and lack of confidence may also appear. Someone suffering from a mental illness may even try to be light-hearted about it, making self-deprecating jokes and the like, but at the end of the day do not hold themselves in high self-regard. This lack of confidence may also be linked to another of the signs someone is hiding a mental illness: social seclusion. Low self-esteem can make it difficult for individuals to approach others, or to feel comfortable in social situations where they feel especially self-conscious.

Substance Abuse

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Substance addiction, including alcoholism, is itself a mental illness. But it also may be a symptom of any one—or more—of many other mental illnesses. Many people who suffer from such mental disorders use substances as a coping mechanism, and with a pathological illness, that coping mechanism can quickly become a dangerous abuse. This is especially true for those who have not sought treatment or help for their illness, as substances play substitute for healthier coping mechanisms that may be developed in therapy or with friends and family. As such, sudden increases in drug or alcohol use is always something to keep an eye on, as it may be a sign of mental illness.

Being Secretive and Defensive

Being secretive and defensive is a sign of someone hiding anything. People who have not opened up about a significant fact of their lives—like mental illness—are almost always going to be at least somewhat and sometimes reclusive and evasive. That may mean canceling plans with strange or false excuses, getting angry when questioned, etc. It's important to remember in this case that if someone is being secretive and defensive about their life, it's not because they've done anything wrong. The best thing to do is not to confront them about their secrecy, but to make it clear that you are only there to be supportive and to help in whatever capacity you can.

Sudden Decline in Work or School

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Working with depression and anxiety, or many other mental illnesses, can drain the motivation and vivacity out of you. For people who suffer from depression, just getting out of bed and showering in the morning, or remembering to eat something, takes a force of will. So when a previously motivated, successful individual suddenly drops off in their work, whether at their job or in school, it could very well be one of the signs someone is hiding a mental illness. Similarly, your mental health plays a crucial role in your ability to concentrate and retain information, so simply learning and performing any kind of complex task can be excruciatingly difficult for someone suffering from such an issue.


When most people think of mental illness, they think of depression: staying in bed all day, feeling sad or angry, disconnecting from the world. But that's just one way a mental illness may manifest itself. On the other side of things, impulsivity and recklessness may equally be a sign of mental illness. For people who suffer from bipolar disorder, periods of mania or hypomania are characterized by these kinds of impulsive actions. Impulsivity may also be a sign of suicidal thoughts, acting without consideration of the consequences because the individual does not plan to be around to face them. Whatever the underlying cause, the sudden emergence of impulsivity or reckless behavior may be a sign of underlying mental illness.

Physical Ailments

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If someone you love is constantly complaining of aches and pains, says it hurts to walk or get out of bed, or gets physically fatigued with minimal exercise, don't just assume they're a hypochondriac, as they are probably experiencing physical symptoms of depression. Mental illnesses can have serious psychosomatic effects, causing very real aches and pains, along with serious fatigue. Due to the nature of these pains, they may also be resistant to the usual cures—aspirin, heating pads, etc.—and persist for long periods of time. For some, these constant aches and pains may persist until an effective treatment method—usually a combination of medication (like anti-depressants) and therapy—has been instituted.

Delusional Behavior or Speech

Depression and anxiety are two of the most common mental illnesses, but they are far from the only ones to watch out for. You won't generally find people who suffer from depression or anxiety alone having delusions or hallucinations, but illnesses like bipolar disorder and schizophrenia, though rarer, can be even more serious. Delusions of invincibility, immortality, and greatness are most particularly common symptoms of mania. Hallucinations, whether audio or visual, are often among the first signs of a psychotic break. These kinds of strange behaviors, when they occur, are almost always signs someone is hiding a mental illness.

Nicola P. Young
Nicola P. Young
Read next: Never In the Cover of Night
Nicola P. Young

Lover of Books, Saxophone, Blogs, and Dogs. Not necessarily in that order. Book blogger at heartofinkandpaper.com.

See all posts by Nicola P. Young