Table 1.
Demographic, lifestyle and dietary characteristics of participants by intervention arm
| Characteristics | Placebo (n = 30) |
Blueberry (n = 30) |
p-Value |
|---|---|---|---|
| Age, years (SD) | 20.1 (1.5) | 19.9 (1.3) | 0.65 |
| Sex, % female | 70 | 66.7 | 0.78 |
| Duration of depressive episode, months (Mdn) | 19 | 27 | 0.12 |
| Ethnicity, % white | 73.3 | 76.7 | 0.77 |
| Low parental educational attainmenta, % | 26.7 | 46.7 | 0.07 |
| Smoking, % occasional or daily | 10 | 13.3 | 0.69 |
| Hazardous alcohol useb, % | 36.7 | 36.7 | 1.0 |
| Vitamin D or multivitamin use, % | 16.7 | 30 | 0.22 |
| Hormonal contraception use, % (women only) | 38.1 | 40 | 0.90 |
| Vegetarian or vegan, % | 10 | 13.3 | 0.69 |
| Body mass index, kg/m2 (SD) | 23.7 (4.4) | 22.8 (2.5) | 0.32 |
| High physical activityc, % ≥ 35 MET-h/wk | 36.7 | 30 | 0.71 |
| Energy intake, kcal/d (SD) | 1740 (638) | 1723 (684) | 0.92 |
| Red and processed meatd, servings/wk | 2.9 | 3.9 | 0.69 |
| Fish and seafoode, servings/wk | 0.9 | 1.2 | 0.60 |
| Legumes and nutsf, servings/wk | 2.1 | 2.0 | 0.82 |
| Whole grainsg, servings/wk | 3.7 | 2.4 | 0.50 |
| Fruit and vegetablesh, servings/d | 4.4 | 4.8 | 0.39 |
| Berriesi, servings/wk | 0.9 | 0.9 | 0.79 |
Variable values are expressed frequencies (%), means and standard deviations (SD), or medians; * denotes p < 0.05
Unless otherwise indicated, p-values are based on chi-square tests for frequency variables, Mann–Whitney U-tests for dietary intakes and depression duration, and independent samples t-tests for age, BMI, and energy intake
aDefined as neither parent holding a university degree; p-value based on Mann–Whitney U-test with continuous scores
bDefined as an AUDIT-C score ≥ 8 for men and ≥ 7 for women
cp-value based on Mann–Whitney U-test with four activity categories
dBeef, beef burgers, pork, lamb, bacon, ham, luncheon meats, sausages, savoury pies
eOily fish, white fish, fish fingers, shellfish
fBaked beans, pulses (e.g., lentils, beans, chickpeas), nuts and peanuts, peanut butter
gWholemeal bread, crispbread, oat porridge, wholegrain cereals, wholewheat pasta, brown rice and quinoa
hApples, pears, banana, grapes, citrus fruits, melon, peaches and plums, pineapple, mango, strawberries/raspberries, blueberries/blackberries, other fruit, carrots, broccoli, Brussels sprouts, green peas, green beans, courgette, cauliflower, parsnip/turnip, leek, onion, garlic, sweet peppers, green salad, spinach/kale (cooked), cucumber/celery, tomatoes, sweetcorn, beetroot, beansprouts, avocado, cabbage, mushrooms
iStrawberries/raspberries, blueberries/blackberries