Bipolar disorder, which is characterized by extreme mood swings, affects nearly 3% of the US population

Subsyndromal affective disorder is diagnosed when someone exhibits two of the nine major criteria for depression (but not more than five) as a result of seasonal changes. While it is milder than primary SAD, SSAD is still significant and impacts millions.

A US government report indicates that about 10% of US adults took prescription medication for this disorder in 2023. Women, at 15.3%, were more than twice as likely to take one of these medications than the 7.4% of men.

Postmortem brain tissue analysis suggests there are genetic and epigenetic similarities between individuals with autism, schizophrenia and bipolar disorder. All three conditions appeared to have activation of genes in astrocytes and suppression of specific genes that function at the junction between neurons, called synapses.

This 2020 research overview surveys the relationship between disrupted circadian clocks and disorders including schizophrenia, anxiety, and bipolar disorder. It incorporates findings and therapeutic approaches drawing from human night shift studies and jet lag studies alongside animal research.

This prevalence trend mirrors the broader incidence of depression among women and is well-documented. Researchers suggest the disparity stems from differences in hormones, social role expectations, coping mechanisms, and more. Men may also present with depression differently, and seek help less.

More than 18% of US adults reported that they currently have or are being treated for depression in both 2024 and 2025. In the 2025 survey, more than 11,000 adults were surveyed. The numbers have ticked upward since 2015—by about 8 percentage points—with most of the increase occurring from the 2020 pandemic onward.

Some researchers have argued in the past couple decades that all mental health disorders may have a unifying dimension—a theoretical "p-factor" that is common across mental illness, but life experiences and behaviors influence if and how illness manifests. Proponents point to similarities across different disorders, while detractors argue that such connections are largely exaggerated.

Menopause, a natural biological process, occurs in three stages: perimenopause (hormone fluctuations), menopause (end of menstrual cycles), and postmenopause (12 months without menstruation). Hormonal shifts during this time can affect neurotransmitters, increasing the risk of mood disorders.

Those with ADHD—chronic issues with attention and executive function—are primed for SAD. Many are disproportionately evening chronotypes (more awake in the evening), have a delayed sleep phase, and have low sensitivity to light in the morning. This podcast explores the overlap between these two groups.

Roughly 1,000 to 4,000 kids are born with these conditions each year in the US though many of the diseases are fatal. Mitochondrial disorders often affect the organs that require the most energy, including the heart, brain, and muscles.

Read this research brief to learn more about why heightened mental health and substance use concerns persist three years after the outbreak of COVID-19. According to a recent survey, the vast majority of American adults view the nation as facing a...

US government data published in 2025 but gathered from August 2021 through August 2023 indicated that depression prevalence among teens aged 12 to 19 was at 19.2%. It was even higher among females of that age group—26.5%

The American Psychiatric Association's DSM-5—used for defining diagnoses—says a person must be experiencing five or more symptoms of depression most of the day over at least two weeks. Research indicates older people are less likely than younger people to meet that depression benchmark, though this article says they still often have at least several of the depression symptoms.

Before professional standards were adopted, practitioners used varying criteria to diagnose mental health disorders. By the 1970s, more objective lists were organized, culminating in this list of polythetic criteria—a list of symptoms where no single criterion is required, but a minimum number must be present.

Schizophrenia's causes remain largely unknown, though scientists suggest it's caused by multiple factors. Its symptoms include disruption of thought processes rather than the exhibiting of multiple personalities. This brief video provides an overview of the condition.

Dizziness, including vertigo, occurs among 15% to 20% of adults. Vertigo can have numerous causes, but generally it's more common with age. It's also much more common among women than in men—occuring roughly two to three times more frequently, sometimes potentially related to the hormonal fluctuations of menopause or to migraines.

The disorder has been increasingly diagnosed as its definition has grown broader and as clinicians have become more adept at identifying it—with some estimates suggesting the figures are much higher. These figures include people across the spectrum, some of whom live mostly independent lives, while others require life-long care and assistance.

Yet menopause isn't talked about as much. In this podcast episode by Houston Methodist, a Texas-based hospital, the host speaks with a gynecologist with a specialization in menopausal medicine about what menopause really is, and how women and the people in their lives can navigate this next life stage.

How often would you say you struggle to stay or fall asleep? If it's more than three times per week (and has been going on for at least one month), then you might have one of the most common sleep disorders: insomnia.

Major depressive disorder is a clinical diagnosis and is not a lifestyle choice. Those who struggle with depression can express persistent feelings that are difficult to process and make sense of for friends and family. This guide walks through some counterintuitive perspectives, including resisting the urge to force a depressed person to do the things that would make them feel better.

Treatment for depression has historically hinged on the theory that the condition was caused by underactive or abnormal neurotransmitters, specifically serotonin and norepinephrine. This four-minute video by Yale Medicine details how these neurotransmitters didn't explain the symptoms of depression but, two other neurotransmitters involved in regulating mood and emotion did. GABA and glutamate, some of the brain's most plentiful neurotransmitters, may possibly be the source of depressive symptoms.

Although the substance is banned in the US, it's legal in Mexico. Americans who have traveled there for treatment, including the NFL's Braden Smith, say the drug helps deal with conditions like obsessive-compulsive disorder.

This comprehensive overview from the Addiction Center uses recent data from SAMHSA’s National Survey to examine the 10 most common substance dependencies in the United States. It ranks addictions from alcohol (affecting 28.3 million Americans) to barbiturates, while highlighting key trends, risks, and societal impacts.

Norman Rosenthal led the team at the National Institute of Mental Health that first identified and described seasonal affective disorder in 1984. This 101 from NIMH explores the basics of the condition, from who develops it to how it is treated.

Civil engineer Herb Kern had bipolar and would record his moods dating back to 1967. He noticed the seasons were a major factor in the increase and severity of his episodes. By reaching out to researchers at the National Institute of Mental Health, Kern became the first human to confirm increased melatonin levels during winter and to receive bright light therapy.

While both psychiatrists and psychologists are mental health professionals, the big difference is that psychiatrists are medical physicians (MD or DO) while psychologists are not. Learn what makes these two profession different with this brief explainer.

Vestibular migraine is a common cause of vertigo, affecting approximately 20% of patients with migraine. It's the most common cause of recurrent, sudden-onset vertigo.

In popular culture OCD has been incorrectly overused to describe neatness or perfectionistic behaviors, but the disorder involves intrusive thoughts and compulsive behaviors that take over a person's actions.

This video explores similarities and differences between these two disorders, which both have genetic causes. Challenges with attention, hyperactivity, and impulsivity are typical of ADHD. Fidgeting, problems picking up on social cues, emotional dysregulation, and being oblivious to time may occur with both disorders—though the impetus for these behaviors may differ.

This map underscores that people in the northeastern United States have more cases of the disease as compared to the south, west, and midwest. On an individual level, these numbers may still differ based on genetic makeup and other factors irrespective of where people live.

Schizophrenia is a particularly shocking mental illness because its symptoms may appear seemingly without any prior signs of illness after a person has had no symptoms for the first couple of decades of their life. Among teens, symptoms may look like typical adolescent behaviors—withdrawal, being irritable, and having trouble sleeping.

Burnout can be accompanied by several symptoms, including low energy and chronic fatigue, trouble concentrating, difficulty sleeping, and depression. It may even manifest physically as musculoskeletal pain, headaches, stomach and intestinal pain, and more. More intense cases have been linked to cardiovascular and mental health disorders.

Using latitude, depression prevalence, and populations of women and those aged 18-30, this map shows the risk of experiencing seasonal affective disorder during the winter. Researchers weighted latitude most (50%) and demographics least (5% each for women and young adults). Overall risk is not a useful predictor of prognosis for an individual.

A large analysis of existing studies published in 2021 found that systemic inflammation is associated with fatigue, appetite changes, and sleep disruption, rather than some of depression's broader symptoms including hopelessness about the future, or feeling fearful. This may suggest that inflammation influences specific symptoms of the condition, rather than the disease as a whole.

Rheumatoid arthritis is an autoimmune condition leading to breakdown and inflammation of multiple joints throughout the body. This academic article provides an updated deep dive into our current cellular understanding of rheumatoid arthritis, how it is diagnosed, and the variety of medications available for treating this painful condition.

Contrary to the name, patients do not have multiple personalities. Rather, the split mind refers to the sufferers' inability to distinguish reality from hallucinations when they are aware and awake. Cognitive difficulties, including challenges focusing and communicating are also common among those with schizophrenia, as well as auditory and visual hallucinations.

The new name, polyendocrine metabolic ovarian syndrome, nods to the hormonal disruptions that cause this condition, which affects roughly one in eight women. People with PMOS may have symptoms including irregular periods, trouble conceiving, weight gain, acne, undesired hair growth, and more. The earlier name, polycystic ovary syndrome, was a misnomer because women with the condition don't have cysts in their ovaries. Rather, they have masses that are actually immature follicles. World health experts think the condition often goes undiagnosed.