Higher Dietary Inflammatory Index Scores are Associated with Increased Odds of Benign Breast Diseases in a Case-Control Study

The association between inflammatory and immune system biomarkers and the dietary inflammatory index in patients with COVID-19

Background

Inflammation and cytokine storm have been reported to be the main cause of acute symptoms of coronavirus disease (COVID-19). Diet-induced inflammation may affect the condition of patients with COVID-19. Therefore, this study aimed to investigate the relationship between disease severity, inflammatory and immune system biomarkers, and the dietary inflammatory index (DII) in patients with COVID-19.

Methods

This cross-sectional study was conducted on 500 adult patients with COVID-19. Patients were divided into mild, moderate, and severe conditions based on clinical and laboratory evidence. A validated food frequency questionnaire (FFQ) was used to determine DII and energy-adjusted DII (E-DII) scores. The serum C-reactive protein (CRP) level and blood cell count were measured for all patients. Multiple linear regression was used to explore the association between DII and E-DII and CRP, blood cell counts, and hospitalization in patients with COVID-19.

Results

Coronavirus disease (COVID-19) patients with higher DII had higher consumption of fat and carbohydrate and lower intakes of protein, anti-inflammatory nutrients, garlic, caffeine, tea, onion, and fiber (P < 0.05). There was a positive association between DII and CRP (β = 1.024, P < 0.001), hospitalization (β = 1.062, P < 0.001), WBC count (β = 0.486, P < 0.009), neutrophil count (β = 0.565, P < 0.001), and neutrophil-to-lymphocyte ratio (β = 0.538, P < 0.001) and a negative association between DII and the lymphocyte count (β = −0.569, P < 0.001). There was a positive association between E-DII and hospitalization (β = 1.645, P < 0.001), WBC count (β = 0.417, P < 0.02), and neutrophil-to-lymphocyte ratio (β = 0.35, P < 0.03).

Conclusion

There is a positive correlation between DII and inflammation, immune hyperactivation, and length of hospital stay in patients with COVID-19. Further longitudinal studies are necessary.

Dietary inflammatory index and breast cancer risk: an updated meta-analysis of observational studies

This updated meta-analysis sought to determine whether the pro-inflammatory potential of diet is a risk factor for breast cancer (BrCa) development, for the first time focusing on the effects of design heterogeneity. The search was performed using Scopus, PubMed, and Embase databases. Data were extracted from twenty-one eligible studies, including eleven cohorts (336,085 participants/20,033 incidence cases), and ten case-control studies (9,833 cases/12,752controls). The random-effect was used to calculate the relative risk (RR) using STATA 16 software. The highest dietary inflammatory index (DII) vs. the lowest category showed 16% increased risk of BrCa (95% CI: 1.06-1.26; I² = 62.8%, P (I²) < 0.001). This was notable in post-menopausal status (RR = 1.13, 95% CI: 1.04-1.22), women with body mass index (BMI) ≥ 30 kg/m² (RR = 1.35, 95% CI: 1.07-1.63), and study populations from developing countries (RR = 1.79, 95% CI: 1.12-2.47). Methodological covariates were subject to subgroup meta-analyses and showed stronger results among case-control studies (RR = 1.50, 95% CI: 1.20-1.80), studies considered age-matched controls (RR = 1.56, 95% CI: 1.19-1.93) and hospital-based controls (RR = 2.11, 95% CI: 1.58-2.64), and cohort studies identified by prolong follow-up durations (RR = 1.13, 95% CI: 1.03-1.22). This updated meta-analysis highlighted the pro-inflammatory diet as a risk factor for BrCa, especially among women in post-menopausal status, obese groups, and developing countries. Meta-analysis in methodological subgroups could improve results, less affected by heterogeneity, and suggested subclassification with important implications for future epidemiological designs and even clinical management.

Strong association between the dietary inflammatory index(DII) and breast cancer: a systematic review and meta-analysis

The association between the Dietary Inflammatory Index (DII) and breast cancer risk has been widely reported in recent years, but there is still controversy about whether a pro-inflammatory diet is a risk factor for breast cancer. We conducted a meta-analysis to investigate the relationship between the DII and breast cancer risk in pre-menopausal and post-menopausal women. We comprehensively searched PubMed, Embase and the Cochrane Library in January 2021 to identify articles reporting an association between the DII and breast cancer risk. A pooled analysis was conducted with 14 studies covering 312,885 participants. Overall, women in the most pro-inflammatory diet category were at greater risk for breast cancer than those in the most anti-inflammatory category (relative risk [RR]=1.37, 95% confidence interval [CI] 1.17-1.60, P<0.001). This association was strong in both pre-menopausal women (RR=1.87, 95% CI 1.17-2.99, P=0.001) and post-menopausal women (RR=1.23, 95% CI 1.08-1.40, P<0.001). Thus, a strong and independent association was observed between a pro-inflammatory diet (assessed using the DII score) and breast cancer risk, irrespective of menopausal status. Further studies will be required to determine the relationship between a pro-inflammatory diet and different subtypes of breast cancer.