It’s completely natural to look at your family’s health history and wonder: “Is that something I could get too?” If a parent, sibling or other close relative has struggled with intense mood swings, you may feel a mix of worry, curiosity and a desire to understand your own risk.

The relationship between our genes, our environment and our mental well-being is fascinating and complex. Here, we’ll explore what the science says about bipolar disorder. It’s not a simple case of “yes or no,” but a fascinating blend of nature and nurture.

Bipolar disorder is a serious mental health condition characterized by extreme shifts in mood, energy and the ability to do daily tasks. These mood swings are much bigger than normal ups and downs. They include emotional highs, called mania or hypomania, and severe lows, called depression.

When someone has mania, they may feel overly happy, super energized or very easily annoyed. They may sleep very little but still feel totally rested, talk very fast, have racing thoughts, or do risky things like spending too much money. When the mood shifts to depression, the person feels intensely sad and/or hopeless, loses interest in things they once loved, and has very low energy. These episodes can last for days, weeks or even months.

Bipolar disorder affects an estimated 4.4% of U.S. adults at some point in their lives, and nearly 3% experience it in any given year. This means millions of people manage this condition every day.

The average age for a first manic episode to appear is around 25 years old, though it can start earlier in childhood or later in adulthood.

Types of bipolar disorder

Bipolar disorder is categorized into a few types, based on the severity and pattern of mood episodes:

Bipolar I disorder

This type is defined by at least one episode of full mania. The manic episode may be preceded or followed by a hypomanic or major depressive episode. The manic episodes are often so severe that they require a hospital stay. 

Bipolar II disorder 

This type involves a pattern of depressive episodes and hypomanic episodes, but never a full manic episode. Hypomania is a less intense version of mania, where a person feels upbeat and energetic, but not as extreme as full mania. The depressive episodes are often quite severe. 

Cyclothymia

This is a milder form where a person has many periods of both hypomanic symptoms and depressive symptoms over at least two years. The symptoms are noticeable but don’t meet the full criteria for an episode of hypomania or major depression.

The role of genetic factors in bipolar disorder 

When you ask, “Is bipolar disorder genetic?” the answer is yes, genes can play a major role. Research shows that a large part of the risk comes from the genes you inherit from your parents. 

Family history: The biggest sign

The clearest sign of a genetic link is seen in family studies:

• Increased risk

People with a first-degree relative, a parent or sibling, who has bipolar disorder have a much higher risk, about 9%, of developing the condition themselves. This is nearly 10 times the risk of the general population. 

• Identical twins

Studies on identical twins, who share all of their genes, show that if one twin has bipolar disorder, the other twin has a risk of up to 70% of also having it. This reflects the importance of the genetic component. 

It’s not just one gene.

Bipolar disorder isn’t caused by a single “bipolar gene.” If it were, identical twins would always both have the condition, 100% chance. Since the risk is high, but not 100%, we know two important things:

• Multiple genes

It’s likely the result of many genes working together, each one adding only a small amount to the overall risk. 

• Genetic vulnerability

Having these genes gives a person a genetic vulnerability or a higher chance of getting the disorder, but it does not guarantee they will develop it. Other factors must often be involved. 

Genes affect your brain.

The genes connected to bipolar disorder are thought to affect how the brain works in several key ways:

• Brain chemistry

Genes influence the chemicals in the brain called neurotransmitters, like dopamine and serotonin, which control mood and energy. Problems with these chemicals can lead to extreme mood shifts in bipolar disorder. 

• Brain structure

Genetics can influence the structure and activity of certain brain areas, especially those responsible for controlling emotions and making decisions.

Experts estimate that genetic factors explain 60% to 85% of the risk for bipolar disorder. This high number confirms that family history is a powerful piece of the puzzle.

The role of environmental factors in bipolar disorder

Again, if genetics were the whole story, identical twins would always share the disorder. The fact that they don’t tells us that our environment and life experiences play a critical role. Environmental factors act as triggers that can flip the switch in a person who is already vulnerable. 

Stressful life events and trauma

One of the most powerful triggers for the start of bipolar disorder, or for triggering a mood episode, is intense stress or trauma. 

• Major life changes 

Highly stressful events like the loss of a loved one, a major breakup or severe money problems can often come before the first episode. 

• Childhood trauma

Experiencing trauma during childhood, such as abuse or neglect, is strongly linked to an increased risk of developing bipolar disorder and can make symptoms worse. Trauma can change how the brain handles stress. 

Substance use

Using drugs or alcohol can be both a symptom of bipolar disorder (people self-medicating for their extreme moods) and an environmental factor that triggers or worsens the condition. 

• Chemical disruption

Substances like alcohol or drugs can seriously disrupt the brain’s delicate chemistry. This can trigger a manic episode in someone who is at risk.

• Complication

Substance use can make bipolar symptoms worse and the condition much harder to treat. 

Sleep disturbances

Sleep is essential for mood regulation, and problems with sleep can be a strong environmental trigger for mood episodes. A sudden, significant change in sleep patterns, such as severe insomnia or traveling across time zones, can sometimes trigger a switch into a manic or hypomanic state. For someone with bipolar disorder, keeping a consistent sleep schedule is one of the best ways to protect their mental health. 

Certain medications and other conditions 

Some medications for other health problems can sometimes trigger a manic episode in a person with a genetic risk.

• Antidepressants

While they treat depression, they must be used carefully, often with a mood stabilizer. In some vulnerable people, taking only an antidepressant can sometimes trigger a manic episode.

Other medical conditions, such as thyroid disorders, can sometimes look like or worsen bipolar symptoms, showing a strong link between physical health and mental health.

Key takeaways of bipolar disorder and the roles of genetics and environment

Here are the most important things to remember about bipolar disorder:

• It’s complex.

Bipolar disorder isn’t caused by one single thing. It’s an interaction between multiple genes and various environmental experiences.

Family history is a risk, not a guarantee.

Even with a high genetic risk, like having a parent with bipolar disorder, the majority of people will not develop the condition. Genes only increase the risk. They don’t seal your fate. 

Your environment can play a powerful role.

You have control over many of the environmental factors that can act as triggers. Managing stress, getting enough sleep and avoiding substance use are powerful ways to protect your mental health. 

Discuss your risk. 

If you’re worried about your family history, the best first step is to have an open, honest talk with a health care provider. They can help you understand your personal risk and suggest proactive steps like specialized therapy.

Find support and personalized treatment with Guidelight Health

Understanding that bipolar disorder is influenced both by your genes and your life experiences can be empowering. It means that while you may have a genetic risk, there are actions you can take to manage your well-being and live a stable, fulfilling life.

At Guidelight, we recognize that every person’s journey with mental health is unique. Our care is built on compassionate care delivered by expert clinicians who truly listen to your story, including your family and personal history.

We are dedicated to providing you with personalized treatment that looks at the whole picture: your genetic background, your life circumstances and your individual symptoms. Treatment for bipolar disorder usually involves a combination of medication management and specialized therapy. We will work with you to find the right combination and plan to bring stability and hope back into your life.

You don’t have to navigate the complexities of bipolar disorder alone. We’re here to offer the kind, welcoming and supportive guidance you need to manage your risk and thrive.

Everyone has a seat at Guidelight. Contact our team online or call us today for more information about bipolar disorder or to schedule an initial evaluation. We provide treatment across the country — and we’re always expanding. See if we offer care in your state, either online or at one of our local clinics.