What Is A Mental Illness? Definition, Examples, and Symptoms

Mental Illness Treatment In Florida

In the US, the rate of mental illness continues to grow each year. The National Institute of Mental Health estimates that over one in five US adults are currently living with a mental illness.

But despite the growing prevalence of mental illness, there’s a lack of awareness as to what constitutes a mental disorder or illness.

This awareness (or a lack thereof) can encourage or prevent someone from seeking help when they need it most.

Similarly, if you know someone who is in need of mental illness treatment in Florida, understanding the signs and symptoms can help you provide better care.

So, it’s worth looking at the definition of mental illness, the different types that exist, and common symptoms that indicate the existence of a disorder.

What Are Mental Illnesses?

The American Psychiatric Association defines mental illnesses as a range of conditions characterized by changes in behavior, thinking, or emotion.

Having a mental illness is often associated with poor functioning in occupational or social activities or clinically significant distress.

Mental Health vs. Mental Illness

Now, you’re probably wondering how mental illness differs from mental health; where one ends and the other begins?

Mental illness includes all diagnosable psychological disorders.

These are health conditions characterized by marked changes in emotions, thinking, and behavior, as well as significant distress and issues with functioning.

In contrast, mental health refers to effective functioning in everyday activities that allow you to be productive at work or school, have healthy relationships, and adapt to changing circumstances.

Most importantly, it helps you cope with stressful situations.

You need balanced mental health to experience healthy emotions, communicate effectively, and learn from your mistakes.

It’s also crucial for your self-esteem, emotional well-being, and contribution to society. And yes, it can be influenced by your physical health.

Types Of Mental Illnesses

There are various ways to classify the types of mental illnesses, including the categories laid out by the APA’s DSM-5.

These conditions can be mild or severe, depending on how they interfere with everyday life.

The severity of the impact can determine the type of care that’s needed.

For instance, people with severe mental illness may require full-time care in a hospital or residential treatment facility.

Common Symptoms Of Mental Illness

The American Psychiatric Association points out that about half of people with mental illnesses develop them at the age of 14, while 3/4th of them begin by the age of 24.

It’s important to consider that conditions such as bipolar disorder or schizophrenia don’t develop overnight.

In most cases, family members, friends, co-workers, and teachers start seeing signs and feel like something isn’t right.

When you’re able to spot early warning signs and developing symptoms, you can ensure immediate treatment without any delays.

Keep in mind that early intervention can prevent mental illness from exacerbating and interfering with your quality of life.

In fact, it may even help you prevent a disorder altogether. Although the specific symptoms can vary, common signs include:

  • Changes in mood: Your mood may shift rapidly or fluctuate between two extremes. Or, you may experience an increase in irritable or depressed mood.
  • Increased or decreased appetite: Marked changes in your appetite or eating habits. You may be eating excessively or very little, characterized by unplanned weight gain or loss.
  • Changes in sleep patterns: Your sleeping patterns may change, causing you to sleep very little or too much, to the extent that it affects your functioning.
  • A decline in functioning: You may display an unusual decline in functioning, indicated by poor performance at work or school.
  • Heightened sensitivity: Feeling more sensitive to smells, sounds, sights, or touch.
  • Social withdrawal and a lack of interest in activities you previously enjoyed.
  • Illogical or magical thinking and exaggerated beliefs, like believing you have powers or can influence real-life events.

Causes and Risk Factors Of Mental Illness

Mental illnesses can occur due to a combination of different reasons, such as:


In most cases, mental illness is inherited since having a blood relative with a mental disorder increases the risk of developing a disorder as well.

Moreover, certain genes can lead to an increased risk of having a mental illness, and environmental factors like distress and adversity can trigger it.

Prenatal Exposure To Toxins 

Sometimes, prenatal exposure to stress and toxins can contribute to a higher risk of mental illness.

This includes exposure to drugs, alcohol, inflammatory conditions, and other stressors.

Differences In Brain Chemistry 

If you look at most disorders, they boil down to differences in brain chemistry. Your neurotransmitters are naturally occurring chemicals that transmit signals to different parts of your brain and body.

Changes in neurotransmitter concentrations can result in disorders such as depression.

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