Short-term diet changes for young adults may significantly reduce depression symptoms, according to results from an Australian randomized controlled trial published in PLoS One.
“Making diet improvements can reduce symptoms of depression in young adults, but importantly, this wasn’t a weight loss diet,” Heather M. Francis, PhD, of the department of psychology at Macquarie University in Sydney, told Healio Psychiatry. “We didn’t place restrictions on amount eaten. It’s really just about increasing the amount of healthy foods and reducing the amount of processed foods.”
According to Francis and colleagues, a global shift has occurred in recent years from diets high in complex carbohydrates and fiber to ones high in processed foods, refined sugars and saturated fats. Previous research suggested an association between an increased risk for depression and poor diet quality. Because diet is a “modifiable risk factor for depression,” the researchers noted that it would be a good area for early intervention; however, little research exists on the potential causal relationship between diet quality and depression among young adults.
To address this gap in research, Francis and colleagues randomly assigned 76 university students aged 17 to 35 years who reported elevated levels of depressions symptoms and habitually poor diets to a 3-week diet intervention or a habitual diet control group. The researchers determined poor diets according to the Australian Guide to Healthy Eating.
The researchers assessed participants’ scores for overall mood, anxiety and depression, as well as their performance on reasoning and learning tasks, both before and after the intervention. Participants in the diet change group were given instructions on improving their diet via a 13-minute video from a registered dietician, as well as a healthy food hamper and $60 toward future groceries. The researchers checked in with these group members via two phone calls. The control group did not receive diet instructions but were asked to return for assessment after 3 weeks.
The researchers found that the diet group reported significantly lower depression symptoms than the control group on two depression subscales, and they achieved “good compliance” with the intervention recommendations based on self-report and spectrophotometry. Those in the diet group also had significantly lower anxiety scores than the control group.
Although only 21% of participants win the diet group fully maintained the diet interventions, those that did maintained their improvements in mood at 3 months follow-up.
“We were really pleased that despite how inexpensive and minimal the intervention was, the diet change group was able to follow the recommendations,” Francis said. “We wouldn’t advocate that diet should replace psychological therapy or medications, but these findings show that it can be an effective adjunct to treatment as usual, and that people with depression could benefit from sessions with a dietitian.” – by Joe Gramigna