TABLE 2.
Data summary of observational studies assessing the effects of polyphenols on depressive symptoms1
| Author | Year | Country | Study design | Main variable | Subjects | Depression scale | Other measures | Results |
|---|---|---|---|---|---|---|---|---|
| Hintikka et al. (39) | 2005 | Finland | Cross-sectional study | Tea consumption | 2011 participants from the Kuopio Depression Study aged 25–64 y (n = 1121 women; n = 890 men) | Beck Depression Inventory | FFQ | Daily tea drinkers had a significantly reduced risk of being depressed (OR: 0.46, 95% CI: 0.3, 0.7). |
| Niu et al. (40) | 2009 | Japan | Cross-sectional study | Green tea consumption | 1058 elderly participants >70 y old | 30-item GDS | Height and weight, blood tests for C-reactive protein. A 75-item diet history questionnaire. | The prevalence of depressive symptoms was 44% lower for participants who consumed ≥4 cups of green tea than for those who consumed ≤1 cup/d (Bonferroni-corrected P ≤ 0.01). |
| Chen et al. (41) | 2010 | China | Prospective cohort study | Tea consumption | 1399 women. Condition: breast cancer survivors. | 20-item CESD | Quality of Life and Medical Outcomes Short-Form 36 Health Survey | Regular tea consumption (>100 g dried tea leaves/mo) was inversely associated with overall depression (OR: 0.64; 95% CI: 0.41, 0.99). |
| Ruusunen et al. (42) | 2010 | Finland | Prospective cohort study | Coffee and tea consumption | 2232 middle-aged men | 18-item Human Population Laboratory Depression Scale | 4-d food record, BMI | Heavy coffee drinkers had a decreased risk of depression compared with nondrinkers (RR: 0.28; 95% CI: 0.08, 0.98). No associations were observed for tea consumption and depression (RR: 1.19; 95% CI: 0.54, 2.23). |
| Li et al. (43) | 2010 | United States | Longitudinal cohort study. Duration: cohort from 1971 to 1982. | Legume consumption | 4869 adults who participated in the NHANES (NHANES I) | CESD | 3-mo FFQ | In premenopausal women, consumption of legumes was associated with an increased risk of depression (P = 0.0148). However, moderate consumption was associated with a lower risk of depression among perimenopausal women (RR: 0.52; 95% CI: 0.27, 1.00). No significant association was found among men or postmenopausal women. |
| Lucas et al. (44) | 2011 | United States | Prospective longitudinal study. Duration: 10-y follow-up. | Coffee consumption | 50,739 women (mean age 63 y) | 36-item short-form health survey | FFQ | Depression risk decreases with increasing coffee intake. Multivariate RR for those consuming ≥4 cups/d was 0.80 (95% CI: 0.68, 0.95; P for trend = 0.02). |
| Feng et al. (45) | 2012 | Singapore | Prospective cohort study | Tea consumption | 1615 older participants aged 55–93 y | 15-item GDS | FFQ | Risk of depression decreased with increasing tea consumption. OR for low, medium, and high tea consumption was 1.15, 0.55, and 0.37, respectively (P for linear trend = 0.01). |
| Feng et al. (46) | 2013 | China | Cross-sectional study | Tea consumption | 1368 older-aged participants ≥60 y | 15-item GDS | Mini Mental State Examination. Tea consumption questionnaire | Daily tea consumption was associated with a reduced risk of depressive symptoms. Weekly tea consumption OR: 0.86 (95% CI: 0.56, 1.32) and daily consumption OR: 0.59 (95% CI: 0.43, 0.81) (P for linear trend = 0.001). |
| Omagari et al. (47) | 2014 | Japan | Cross-sectional study | Coffee consumption | 89 participants with type 2 diabetes (n = 34 women; n = 55 men) | Japanese version of the Hospital Anxiety and Depression Scale | FFQ and BMI | Coffee consumption was inversely associated with depressive symptoms, with participants who drank ≥3 cups/d having a significantly reduced risk of depression (P = 0.032). |
| Pham et al. (48) | 2014 | Japan | Cross-sectional study | Green tea and coffee consumption | 537 men | CESD | Diet history questionnaire, C-reactive protein and folate blood test. | Higher green tea consumption (≥4 cups/d) was associated with a significantly lower prevalence of depressive symptoms (51% lower prevalence odds) (P for trend = 0.01). Coffee consumption was also inversely associated with depressive symptoms, with ≥2 cups/d compared with 1 cup/d OR: 0.61 (95% CI: 0.38, 0.98). |
| Yu et al. (49) | 2015 | China | Cross-sectional study | Soybean and soybean product consumption | 1717 Liaoning Province residents aged >65 y (n = 849 women; n = 868 men) | PHQ-9 | FFQ | Frequent consumption of soybeans and soybean products was associated with a decrease in the likelihood of depressive symptoms. Consumption 2–3 times/wk OR: 0.36 (95% CI: 0.15, 0.87; P = 0.23). Consumption >4 times/wk OR: 0.50 (95% CI: 0.34, 0.74; P = 0.001). |
| Li et al. (50) | 2016 | China | Cross-sectional study | Tea consumption | 9371 elderly (≥60 y of age) participants (n = 4853 women; n = 4518 men) | PHQ-9 | Daily living scale and the Mini Mental State Examination. FFQ | Black tea drinkers had a significantly decreased risk of depressive symptoms (P ≤ 0.01) compared with nondrinkers (adjusted OR: 0.48; 95% CI: 0.23, 0.99 and OR: 0.35; 95% CI: 0.17, 0.72 for participants consuming <3 cups and ≥3 cups of black tea per day, respectively) (P for trend < 0.01). |
| Chang et al. (51) | 2016 | United States | Longitudinal cohort study. Duration: 1976–2001 | Dietary flavonoid intake | 82,648 women who participated in the Nurses’ Health Study | The 5-item mental health index, the CESD-10, and the GDS | FFQ | Greater intakes of dietary flavonoids were significantly associated with a modest reduction in depression risk. Participants in the highest flavonoid consumption group had a 7–10% reduction in depression risk compared with the lowest intake group. There was evidence of an inverse linear trend across consumption groups (P-trend = 0.08, 0.0004, and 0.0007, respectively). |
| Su et al. (52) | 2016 | China | Cross-sectional study | Nut consumption | 13,626 adults who participated in the Tianjin Chronic Low-Grade Systemic Inflammation and Health Cohort. Recruited during 2013–2014. | ZSDS | FFQ | Frequent nut consumption is associated with lower prevalence of depression (OR: 0.82; 95% CI: 0.75, 0.90 for consumption 1–3 times/wk and OR: 0.82; 95% CI: 0.73, 0.92 for consumption ≥4 times/wk). |
| Chan et al. (53) | 2018 | Singapore | Prospective cohort study | Tea consumption | 614 elderly participants aged ≥60 y | 15-item GDS | Geriatric Anxiety Scale. Tea consumption questionnaire. | Long-term tea consumption was significantly associated with reduced odds of depressive symptoms. Tea consumption for >15 y resulted in lower GDS scores (OR: 0.82; P = 0.01). |
| Navarro et al. (54) | 2018 | Spain | Longitudinal cohort study | Coffee consumption | 14,413 middle-aged participants | Validated physician diagnosis of depression using the Structured Clinical Interview for DSM-IV | FFQ | Greater coffee consumption is associated with reduced risk of depression. Participants who drank ≥4 cups/d showed a significantly lower risk of depression than participants who drank <1 cup of coffee per day (HR: 0.37; 95% CI: 0.15, 0.95). |
| Miyake et al. (55) | 2018 | Japan | Cross-sectional study | Soy isoflavones | 1745 pregnant women who participated in the Kyushu Okinawa Maternal and Child Health Study (an ongoing prospective prebirth cohort study) | CESD | Diet history questionnaire | Isoflavone intake was associated with a lower prevalence of depressive symptoms during pregnancy. Prevalence ratios (95% CIs; P for trend): 0.63 (0.47, 0.85; 0.002), 0.72 (0.54, 0.96; 0.007), 0.74 (0.56, 0.98; 0.04), 0.57 (0.42, 0.76; <0.0001), 0.73 (0.55, 0.98; 0.03), 0.65 (0.49, 0.87; 0.003), and 0.63 (0.46, 0.86; 0.002). |
| Yu et al. (56) | 2018 | China | Cross-sectional study | Soy isoflavones | 13,760 adults who participated in the Tianjin Chronic Low-Grade Systemic Inflammation and Health Cohort | ZSDS | FFQ | Moderate intake of soy foods may reduce the incidence of depression, whereas high intakes may worsen depressive symptoms. OR: 95% CI (vs. <1/wk) were 0.80 (0.67, 0.95) for 1–3/wk, 0.69 (0.55, 0.86) for 4–7/wk, and 1.85 (1.21, 2.80) for ≥2/d. |
| Godos et al. (57) | 2018 | Italy | Cross-sectional study | Dietary polyphenols | 1572 adults who participated in the Mediterranean Healthy Eating, Lifestyle and Aging study | CESD | FFQ | Higher dietary flavonoid intake may be inversely associated with depressive symptoms (P for trend < 0.001). Dietary intake of phenolic acid (OR: 0.64; 95% CI: 0.44, 0.93), flavanones (OR: 0.54; 95% CI: 0.32, 0.91), and anthocyanins (OR: 0.61; 95% CI: 0.42, 0.89) showed significant inverse association with depressive symptoms, when comparing the highest with the lowest quartile. |
| Mofrad et al. (58) | 2019 | Iran | Cross-sectional study | Dietary phytochemicals | 488 women aged 20–50 y | Depression, anxiety, stress scale | FFQ | Higher consumption of dietary phytochemicals is associated with a decrease in depressive symptoms (OR: 0.22; 95% CI: 0.12, 0.38; P ≤ 0.001). |
1
CESD, Center for Epidemiologic Studies Depression Scale; GDS, Geriatric Depression Scale; PHQ, Patient Health Questionnaire; ZSDS, Zung Self-Rating Depression Scale.