Australian researchers recently published a study in the journal Nutritional Neuroscience, showing a connection between diet quality and depression.
The researchers recruited nearly 250 participants (3 out of 4 of whom had major depressive disorder) and measured their depression levels, as well as dietary quality (including foods eaten, frequency, and portion size) over the previous 12 months.
Diet intake categorized foods into 10 groups:
- Fruit
- Vegetables
- Dairy
- Protein
- Processed grains
- Whole grains
- Nuts
- Fish
- Unsaturated to saturated fats ratio
- Extras ratio
Researchers allocated points for each food group based on whether a participant’s daily intake of each food group met “a combination of the calculated mean g/day for each food group” and the Australian Dietary Guidelines’ recommended daily intake of each food group.
| Food group | RDI | Intake per day | Scoring |
|---|---|---|---|
| Vegetables | 350 g | 118.20 g | 1 point = 0–118.2 2 points = 118.2–350 3 points = 350+ |
| Fruit | 270 g | 158.60 g | 1 point = 0–158.6 2 points = 158.6–270 3 points = 270+ |
| Whole grains | 1500 kJ | 733.95 kJ | 1 point = 0–733.95 2 points = 733.95–1500 0 points = 1500+ |
| Processed grains | 1500 kJ | 815.57 kJ | 1 point = 0–815.57 2 points = 815.57–1500 0 points = 1500+ |
| Dairy | 1250 kJ | 752.62 kJ | 1 point = 0–752.62 2 points = 752.62–1250 1 point = 1250+ |
| Protein | 1250 kJ | 804.13 kJ | 1 point = 0–804.13 2 points = 804.13–1250 1 point = 1250+ |
| Nuts | 30 g | 9.68 g | 1 point = 0–9.68 2 points = 9.68–30 3 points = 30+ |
| Seafood | 100 g | 41.35 g | 1 point = 0–41.35 2 points = 41.35–100 3 points = 100+ |
| Fats ratio | Higher ratio = better | 0 points = 0–0.30 1 point = 0.30–0.60 2 points = 0.60–1.0 |
|
| Extras ratio | Lower ratio = better | 2 points = 0–0.25 1 point = 0.25–0.5 0 points = 0.5–1.0 |
What they discovered was that participants who had lower dietary quality had an increased depression risk. Likewise, participants with higher dietary quality and decreased depression risk.
This study joins a growing body of research showing a strong connection between nutrition and mental health. Here at Truehope, we’ve been promoting nutrition as mental health treatment for over 20 years.