Impact of Krill Oil Supplementation on Alternate-Day Fasting in Adults With Overweight and Obesity: Findings From a Randomized Trial

Diet is widely recognized as an important determinant of health, yet the associations between individual macronutrients and mental health remain unclear. To address this, we conducted a cross-sectional study of 129 healthy adults using an online food frequency questionnaire along with validated measures of depression, anxiety, and early life experiences. Among participants, 31% reported moderate or severe anxiety and/or depression. Sugar-sweetened beverage intake was positively associated with depressive symptoms (β = 4.827; 95% CI: 0.954–8.7; p = 0.015), while dietary fibre intake was negatively associated with anxiety (β = –2.306; 95% CI: –3.791 to –0.82; p = 0.003). Moderate caffeine consumption (100–300 mg) was linked to reduced depression (β = –4.099; 95% CI: –7.049 to –1.15; p = 0.007), suggesting a possible U-shaped effect, and women reported higher rates of both depression and anxiety. We also observed preliminary evidence of an association between high-fructose corn syrup and depressive symptoms and a protective role of fibre against anxiety. Overall, these findings highlight specific dietary factors linked to mental health, warranting further prospective studies with repeated dietary assessments to confirm and extend these results.