{"id":619730,"date":"2026-10-03T20:38:07","date_gmt":"2026-10-03T20:38:07","guid":{"rendered":"https:\/\/www.newsbeep.com\/nz\/619730\/"},"modified":"2026-10-03T20:38:07","modified_gmt":"2026-10-03T20:38:07","slug":"one-diet-change-may-ease-depression-symptoms-in-just-4-weeks-small-trial-finds-sciencealert","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/nz\/619730\/","title":{"rendered":"One Diet Change May Ease Depression Symptoms in Just 4 Weeks, Small Trial Finds : ScienceAlert"},"content":{"rendered":"

A packet of snacks. A sugary drink. A meal ready in minutes. Ultra-processed foods make life easier in the kitchen. Researchers are investigating whether eating fewer of them could also make a difference to depression<\/a> symptoms.<\/p>\n

In a pilot trial, people diagnosed with depression had lower symptom scores during a diet low in ultra-processed foods than during their usual diet.<\/p>\n

Each dietary period lasted four weeks, giving researchers a chance to compare two eating patterns in the same people.<\/p>\n

The study, led by psychiatry researcher Nyasha Chagwedera at the University of California, San Francisco (UCSF), recruited 20 adults who consumed substantial amounts of ultra-processed foods.<\/p>\n

Their average age was approximately 44, and they had lived with depression for an average of nearly 13 years.<\/p>\n

Participants were randomly assigned to start with one of two diets. One group ate as usual for four weeks, while the other reduced ultra-processed foods. Then they switched.<\/p>\n

Participants bought their own food with guidance from researchers. They agreed to keep medications, therapy, exercise, and sleep unchanged throughout the study.<\/p>\n

Nineteen people completed the trial. Average scores on a questionnaire assessing highly processed food consumption dropped from 10.10 at baseline to 1.42 after the intervention.<\/p>\n

Three separate depression assessments recorded lower scores during the low-ultra-processed-food period than during the usual-diet period.<\/p>\n

On the nine-question PHQ-9 assessment, average scores were 8.68 during the usual diet and 5.53 during the dietary intervention. An analysis accounting for baseline symptoms, diet order, and study period estimated a difference of about three points between the diets.<\/p>\n

On another depression assessment, the MADRS, average scores were 18.9 during the usual diet and 8.05 during the low-ultra-processed-food diet.<\/p>\n

The third depression assessment and an anxiety questionnaire also recorded lower scores during the dietary intervention.<\/p>\n

Earlier observational studies have linked higher ultra-processed food consumption with depression<\/a>. Here, researchers explored what happens when people already living with depression change their eating habits.<\/p>\n

That meant asking participants to alter familiar routines. Packaged snacks and some ready-made products offer convenient options when time and energy are limited, though not all processed foods are ultra-processed<\/a>. <\/p>\n

Reducing ultra-processed food can be challenging “because it’s highly palatable, cheap, and convenient”, Chagwedera explains<\/a>.<\/p>\n

Participants’ average rating for the ease of the intervention was 5.74. Their average rating for its usefulness was 8.42, and no adverse events were reported.<\/p>\n

The researchers concluded that the approach was feasible and acceptable, providing a basis for larger trials.<\/p>\n

Reducing ultra-processed foods can also change sugar, fat, or calorie intake. Processing-related contaminants or additives are other possible factors. This study could not determine which aspects of the dietary change mattered.<\/p>\n

Symptoms were also lower during the usual-diet period than at baseline. For example, average PHQ-9 scores were 12.8 at the start of the study, compared with 8.68 during the usual diet. <\/p>\n

The reported dietary effect therefore concerns the difference between the two diet periods, rather than attributing the entire improvement from baseline to reducing ultra-processed foods.<\/p>\n

The trial was small and unblinded: participants knew which diet they were following, so expectations could have influenced the results. Food consumption was self-reported, with no objective measure of ultra-processed food intake.<\/p>\n

All participants had high body weight and reported at least one metabolic abnormality. The findings may therefore not apply equally to other people with depression.<\/p>\n

The primary outcomes were feasibility and acceptability. Depression and anxiety outcomes were exploratory, and the authors describe these findings as hypothesis-generating.<\/p>\n

The researchers call for larger, blinded studies that use objective measures of ultra-processed food intake and investigate the mechanisms behind the results.<\/p>\n

The research has been published in JAMA Psychiatry<\/a>.<\/p>\n

This article was fact-checked by Rebecca Dyer<\/a> and edited by Rebecca Dyer<\/a>. While we pride ourselves on our process, we are only human. If you spot a mistake, please let us know<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"A packet of snacks. A sugary drink. A meal ready in minutes. Ultra-processed foods make life easier in…\n","protected":false},"author":2,"featured_media":619731,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[35],"tags":[134,554,555,1021,111,139,69],"class_list":["post-619730","post","type-post","status-publish","format-standard","has-post-thumbnail","category-mental-health","tag-health","tag-mental-health","tag-mentalhealth","tag-msft-content","tag-new-zealand","tag-newzealand","tag-nz"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/619730","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/comments?post=619730"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/619730\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media\/619731"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media?parent=619730"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/categories?post=619730"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/tags?post=619730"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}