Onions, wholegrains and legumes sometimes get a bad wrap for worsening irritable bowel syndrome symptoms, but new research shows they might offer more than first thought.
A study found people who followed a Mediterranean diet not only had less painful IBS symptoms, they also had better mental health.
It raised the question whether such a diet - often containing ingredients avoided by people with the syndrome - needed to be rethought and people were missing out on other benefits.
The study followed 59 people across six weeks who either followed the Mediterranean diet via counselling from a dietitian, or ate their usual diet (control group).
The results found 83 per cent of people on the Mediterranean diet had a reduction in their IBS-SSS score (gut symptom severity score) compared with 37 per cent in the control group.
But also, depressive symptoms were lower in the Mediterranean diet compared with the control group once the study ended. There were also fewer instances of gastrointestinal symptoms in the Mediterranean diet group compared with the control group.
How can the Mediterranean diet help?
Dr Heidi Staudacher is National Health and Medical Research Council Emerging Leadership Fellow at Deakin University's Food & Mood Centre.
She said it was common for people with IBS to avoid some foods in a Mediterranean diet, including legumes, certain wholegrains and onion, as they're known to worsen symptoms.
But the research suggested there might be a different way to approach managing IBS symptoms without cutting out foods that promote good health.
Dr Staudacher said previous research have shown the Mediterranean diet improves depressive symptoms, plus many people with IBS also have mental health problems including anxiety and depression.
"Given the known gut-brain connection, it is plausible that if we can improve people's mental health this might then lead to improvements in the gut symptoms that people with IBS live with," she said.
The next step is to conduct a bigger study that compares a Mediterranean diet to a better control diet to give more clarity about its effect on gut and psychological symptoms.
Dr Staudacher's research was published in Alimentary Pharmacology & Therapeutics.
