WEDNESDAY, July 28, 2004 (HealthDayNews) -- If you have those occasional days when you feel sad or blue or depressed, a new study finds you're in good company.
The researchers found that, on average, adults had these feelings about three days a month, with women reporting them 3.5 days a month and men reporting them 2.4 days a month.
"This is the first study that looked at this measure of depression," said lead researcher Rosemarie Kobau, a public health analyst at the U.S. Centers for Disease Control and Prevention's National Center for Chronic Disease Prevention and Health Promotion.
"Mood disorders are a major public health problem in the U.S.," she said. "They impose a substantial burden of disability and impaired quality of life."
But, she added, "feeling sad, blue or depressed three days a month as a result of a stressful life situation is perfectly normal."
However, when people are depressed or lose interest in things that they previously enjoyed for more than about two weeks a month, that's the sign of a problem, she said.
Kobau said the number of people with depressive disorders in the United States remains around 11 percent, depending on how depression is measured.
She and her colleagues studied 166,000 responses to the question: "During the past 30 days, for about how many days have you felt sad, blue, or depressed?"
Among their other findings, Kobau's team found young adults (those between the ages of 18 and 24) reported the highest number of days with depressive symptoms. On the other hand, staying active warded off the blues: People who exercised had 1.3 fewer days with depressive symptoms than did those who did not exercise, the study found.
The study also found that if money doesn't necessarily buy happiness, it was associated with a less likelihood of being down. The same was true of education. "Depressive symptoms were associated with lower levels of education and income, as well as unemployment or the inability to work," Kobau said.
College graduates and people with incomes over $50,000 had two sad, blue or depressed days a month, compared with almost five days for people without a high school education and 6.1 days for people with yearly incomes of less than $15,000.
People unable to work had the most sad, blue or depressed days a month -- an average of 10.2 days, according to the report in the July 28 issue of Health and Quality of Life Outcomes.
In addition, people who reported more days with depressive symptoms reported engaging in unhealthy behaviors such as cigarette smoking, binge drinking and not using seat belts, Kobau said. "Most of those unhealthful behaviors are among the leading risk factors for disease and death in the U.S," she added.
"The findings from the study highlight the relationship between depressive symptoms and behaviors that are risky to health. Taking mental health into account when designing public health interventions can help improve people's coping skills and result in better health outcomes," Kobau said.
"Individuals who are troubled by unexplained sadness, lack of interest in life, if they find themselves in a constant blue mood, have low energy, or a recognized substance abuse, they should talk to their health-care provider to get treatment," she advised.
"This is a significant study which answers some important questions and raises new ones," said Dr. Ian A. Cook, an associate professor of psychiatry from UCLA's Neuropsychiatric Institute.
While earlier work has shown that people with major depression have increased disability, reduced quality of life, and increased mortality, this study expands what is known about less severe levels of depression -- called subsyndromal depression -- and sadness, Cook added.
Differences reported about the relationship of subsyndromal depression to age, gender and socioeconomic condition raise questions about target populations for whom interventions may be particularly valuable, he said.
"The connection between subsyndromal depression and unhealthful behaviors suggests that health-care providers should look for subsyndromal levels of depression in their patients who are engaging in deleterious behaviors," Cook said. "In addition, some form of intervention to address mood problems could have significant impact on the health of the public."
More information
Learn about depression from the National Mental Health Association.
