Does the Dietary Inflammatory Index change after Nutritional Therapy in clients who self-report depression in a student nutrition clinic? A retrospective case study
By Michelle Porter - Nutrition Science and Practice
Abstract
Background:
The relationship between diet, inflammation and depression is unclear. Research in the field of nutritional psychiatry is advancing understanding, with dietary interventions for depression focusing on a modified Mediterranean diet. The Dietary Inflammatory Index (DII) provides a measure of inflammatory potential and has been used widely in epidemiological studies. It is applied here to explore changes in dietary inflammatory potential in five cases featuring depression from a student nutrition clinic.
Aim:
To analyse changes in DII after Nutritional Therapy (NT) sessions in clients who self-report depression in a student nutrition clinic.
Methodology:
A mixed methods approach was used to explore quantitative and qualitative elements of this case study. Five cases reporting depression were identified from the clinic. DII scores were calculated from diet diaries pre- and post-intervention. A qualitative comparison of dietary interventions was conducted using elements of framework analysis.
Findings:
After NT, inflammatory potential as measured by the DII decreased in three cases and increased in two cases. Two cases moved from a pro-inflammatory to an anti-inflammatory score. Overall, the changes in DII score failed to reach statistical significance (t (4) =1.278, p=0.270). Notable food parameters which contributed to the changes were fibre and protein sources. Common themes found in both the research and clinic data were recommendations to increase intake of fruit and vegetables, nuts and seeds, seafood and decrease intake of sweets.
Conclusion:
This study successfully demonstrates a novel application of the DII in a clinic setting. There was not enough evidence to prove that the changes in DII after NT were statistically significant. A reduction in inflammatory potential was found in three cases. Exploration of changes in individual food parameters offered an insight into their inflammatory impact. Effective recommendations to increase fibre may offer a useful strategy to reduce dietary inflammatory potential and attenuate depression. The DII offers a useful tool to NT practitioners wanting to reduce inflammatory potential in their clients.
