Academic stress may affect uni students’ mental health; walnuts may come to aid

Academic stress may take a toll on the mental health status of university students, particularly during examination periods, but walnut consumption may help thwart such negative effects, a study from Australia has shown.

“We found that academic stress in undergraduate university students had a negative impact on overall mental health, exacerbating self-reported levels of stress and depression, and resulting in significant mood disturbances [during the exam period],” said the researchers. “[Our study also showed that] daily walnut consumption improved mental health indicators and protected against some of the negative effects of academic stress on metabolic and stress biomarkers.”

Eighty undergrads (mean age 22 years, 75 percent female) were randomized to either the treatment or control arm. Those in the treatment arm were asked to consume a portion (56 g) of walnuts daily for 16 weeks, while control participants were to refrain from consuming any type of nut or fatty fish within the same period. Participants attended clinical visits at the beginning of the semester (V1), during the exam period (V2), and 2 weeks after exams (V3). [Nutrients 2022;14:4776]

Mood

Compared with V1, V2 saw an increase in mean Total Mood Disturbance scores in the POMS* (7.6; p=0.047 [treatment] and 14.1; p=0.011 [control]). “[These imply] that overall, academic stress experienced at V2 had a negative effect on mood in participants,” said the researchers.

Walnut consumption did not attenuate increases in the scores for any of the POMS dimensions. In the control arm however, mean scores for Confusion-Bewilderment, Fatigue-Inertia, and Tension-Anxiety increased from V2 to V1 (1.5, 4.2, and 3.4, respectively) but dropped by V3 (–1.9; p=0.006, –4.0; p=0.002, and –4.9; p=0.002). “[These indicate] that these dimensions contributed to the increased total mood disturbance observed at V2,” they said.

Mental health

In the control arm, there was a significant reduction in the AQoL-8D** Overall Quality of Life mean score at V2 compared with V1 (–3.2; p=0.0297), as well as in the dimensions of coping (–8.0; p=0.012) and mental health (–7.2; p=0.011). “These suggest that academic stress experienced at V2 increased perceived feelings of sadness and worry, and decreased perceptions of being able to cope with problems [among control participants],” the researchers noted.

These effects were not observed in the treatment arm. The near-significant interaction effect in the mental health dimension among walnut consumers suggest that walnuts prevented mental health decline during the exam period, they said.

MHC-SF*** Psychological Wellbeing dimension mean score dropped from V1 to V2 in the control arm (–3.24; p=0.002). “[This indicates] that the psychological wellbeing of control participants was negatively impacted by academic stress at V2,” they said. Again, those in the treatment arm did not experience this effect, underpinning the protective effect of walnuts on mental health.

For DASS21^#, the control arm had significant increases in the mean Depression and Stress subscale scores at V2 (4.7; p=0.0002 and 5.3; p=0.0003, respectively). These effects were not seen in the treatment arm. These imply that stress during exams increased perceived measures of depression and stress, while walnut consumption appeared to stabilize these negative emotional states.

Metabolic biomarkers

In the control arm, total protein levels dropped from V1 to V2 and V3 (from 74.9 to 72.9 and 72.6 g/L). “A poorer diet later in the semester, particularly during the exam period, may have contributed to these lowered levels,” the researchers noted. The corresponding levels were greater in the treatment arm across all timepoints (77.0, 77.1, and 75.7 g/L, respectively).

Serum albumin levels of walnut consumers were greater than those of controls, both at V2 (48.9 vs 45.7 g/L) and V3 (48.1 vs 45.3 g/L). “Given that albumin contributes to 60 percent of total protein levels, together, these results suggest that the incorporation of walnuts in the diet may increase albumin levels,” said the researchers. “This may be of importance since lowered albumin levels have been independently associated with both malnutrition and inflammation.”