Dietary phytochemical index in relation to risk of glioma: a case-control study in Iranian adults

Association between dietary phytochemical index and risk of benign prostatic hyperplasia: a case-control study

BACKGROUND

Dietary intake of phytochemicals has been associated with a reduced risk of chronic diseases, but research on their relationship with benign prostatic hyperplasia (BPH) is limited. This case-control study aimed to investigate the association between a Dietary Phytochemical Index (DPI) and BPH risk in a Middle-Eastern population.

METHODS

The study recruited 112 BPH patients and 112 age-matched healthy controls (40-75 years) from Al-Zahra Hospital Clinic in Isfahan, Iran between 2021 and 2022. Dietary intake was assessed using a validated food-frequency questionnaire, and DPI was calculated as the ratio of energy intake from phytochemical-rich foods to total daily energy intake. Logistic regression analysis was performed, adjusting for potential confounders.

RESULTS

In the crude model, participants in the highest DPI tertile had a 70% lower odds of BPH compared to those in the lowest tertile (OR:0.3, 95% CI 0.15-0.61, P-trend = 0.001). After adjusting for confounders, this inverse association remained significant (OR:0.23, 95% CI 0.15-0.63, P-trend = 0.001). Participants with higher DPI consumed more whole grains (p = 0.02), nuts (p < 0.001), legumes (p = 0.02), fruits (p < 0.001), vegetables (p < 0.001), olives and oilve products (p = 0.02), and tomato and its products (p < 0.001) in their diet compared to the lowest tertile. However, red meat (p = 0.03) and refined grains (p < 0.001) were consumed in higher amounts in the lowest tertile compared to the highest DPI tertile.

CONCLUSIONS

This study demonstrates a protective association between DPI and BPH risk in the Middle-Eastern population. Encouraging higher intake of phytochemical-rich foods may help reduce the risk of BPH, highlighting the relevance of nutritional science in promoting prostate health.

Phytochemicals and Glioma: Results from Dietary Mixed Exposure

The information about phytochemicals' potential to prevent cancer is encouraging, including for glioma. However, most studies on phytochemicals and glioma mainly focused on preclinical studies. Their epidemiological studies were not sufficient, and the evidence on the dose-response relationship is usually limited. Therefore, this investigation examined the association between dietary phytochemical intake and glioma in Chinese adults. This case-control study was carried out in a hospital in China. Based on the dietary information obtained from the food frequency questionnaire, the researchers estimated the phytochemical intake of 506 patients with glioma and 506 controls. Compared with participants in the lowest tertile, the highest intakes of carotene, flavonoids, soy isoflavones, anthocyanin, and resveratrol were associated with a reduced risk of glioma. The WQS and BKMR models suggested that anthocyanin and carotene have a greater influence on glioma. The significant nonlinear dose-response associations between dietary phytochemicals and glioma were suggested using the restricted cubic spline function. According to this study on phytochemicals and glioma, higher intakes of carotene, flavonoids, soy isoflavones, anthocyanins, and resveratrol are linked to a lower risk of glioma. So, we might not be able to ignore how phytochemicals affect gliomas.

Healthy dietary patterns, foods, and risk of glioma: A systematic review and meta-analysis of observational studies

Background

Accumulating epidemiological evidence has shown the favorable associations between healthy dietary patterns and risk of glioma, although the results remain inconclusive.

Objective

We therefore carried out a systematic review and meta-analysis to summarize the evidence from previous published studies, and to clarify the effects of healthy dietary patterns, typical healthy foods on glioma.

Methods

PubMed, Web of Science, CNKI, and Wan fang data were searched from inception up to September 2022 for eligible studies. Two authors independently performed the literature search, study selection, data extraction, and quality assessment. Heterogeneity across studies was estimated using the Cochran's Q test and I ² statistic. According to heterogeneity, the fixed-effects model or random-effects model was selected to obtain the relative risk (RR) of the merger. Subgroup analysis, sensitivity analysis and publication bias were also used for our analysis.

Results

Twenty-four articles that met the selection criteria, involving 7,278 glioma cases and 2,143,528 participants, were included in our analysis. There was a reduced risk of glioma in the highest compared with the lowest categories of healthy dietary patterns (RR = 0.58; 95% CI: 0.44-0.77; P < 0.0001). Moreover, compared with the lowest intakes, the highest intakes of vegetables (RR = 0.84; 95% CI: 0.73-0.96; P = 0.012) and fruits (RR = 0.85; 95% CI: 0.72-1.00; P = 0.045) significantly reduce the risk of glioma. However, the intakes of fresh fish, nuts, whole grains, and dairy products showed no statistically significant associations with the risk of glioma (P > 0.05).

Conclusion

Findings from this systematic review and meta-analysis indicate that higher intakes of healthy dietary patterns, vegetables, and fruits are significantly associated with the lower risk of glioma. Further studies, particularly with prospective design, are required to confirm our findings.