Poor health and lifestyle factors may adversely affect memory, according to a recent study.

Researchers from the University of California, Los Angeles found that people who are depressed, don't get enough exercise or have high blood pressure have an increased risk of self-perceived memory complaints across all adult age groups.

"In this study, for the first time, we determined these risk factors may also be indicative of early memory complaints, which are often precursors to more significant memory decline later in life," Gary Small, senior author of the study and professor of psychiatry and biobehavioral sciences at the Semel Institute for Neuroscience and Human Behavior at UCLA, said in a statement.

For the study, UCLA researchers and the Gallup organization polled more than 18,000 people about their memory and a variety of lifestyle and health factors previously shown to increase the risk of Alzheimer's disease and dementia. The individuals polled ranged in age from 18 to 99.

The known risk factors the researchers focused on included depression, lower education levels, physical inactivity, high blood pressure, diabetes, obesity and smoking.

The researchers found that those risk factors increased the likelihood of memory complaints in younger adults, middle-aged adults, and older adults. Depression was the strongest single risk factor for memory complaints in all age groups.

Twenty percent of those polled had memory complaints, including 14 percent of younger adults, 22 percent of middle-aged adults and 26 percent of older adults.

Having just one risk factor significantly increased the frequency of memory complaints, regardless of age, according to researchers. Memory complaints rose when the number of risk factors increased.

However, researchers acknowledged that, in general, memory issues in younger people may be different from those that plague older individuals. For younger adults, stress may play more of a role, and the ubiquity of technology -- including the Internet and wireless devices, which can often result in constant multi-tasking -- may impact their attention span, making it harder to focus and remember.

Researchers said the findings may help scientists better identify how early lifestyle and health choices impact memory later in life.

The findings were recently published in the journal PLOS ONE.