Review for 10.1186/s12876-025-03859-2 (2025)

Title: Association between adhering to a dietary approach to stop hypertension and risk of
colorectal cancers: A systematic review and meta-analysis
Version: 1 Date: 30 Jan 2025
Reviewer's report:
Abstract:
Methods Section Could Be More Detailed:
1. Which databases were searched? Were there any inclusion/exclusion criteria for studies?
2. Were any subgroup analyses performed (e.g., based on geographic region, age, or diet
adherence level)?
3. Did the meta-analysis assess publication bias or heterogeneity between studies?
4. Were any adjustments made for confounding factors such as physical activity, BMI, smoking,
or genetic predisposition in the included studies?
5. How was the quality of the included studies assessed? Did any studies show significant bias?
6.Did the effect sizes differ across different population groups (e.g., Western vs. Asian cohorts)?
7.Were there any limitations in the included studies that might affect the interpretation of the
results?
8.The discussion notes studies where DASH was protective only in men, while others found
effects in both sexes.
Suggestion: Explicitly discuss possible biological or lifestyle-related reasons for these
discrepancies (e.g., hormonal differences, dietary adherence patterns).
Clarification of Effect Sizes Across Studies:
9. Some studies report a relative risk reduction, while others report odds ratios or hazard ratios.
It would be helpful to clarify if these measures are directly comparable in the context of CRC
risk assessment.
10. The conclusion states that the DASH diet has a more "prominent" effect on CRC risk
compared to the Mediterranean diet, but the evidence is mixed.
Suggestion: Provide more details on whether the weaker association in Mediterranean diet
studies is due to adherence levels, population differences, or study designs.
11. The explanation of fiber’s role is good, but it would be helpful to mention if any specific
types of fiber (e.g., soluble vs. insoluble) are particularly relevant.
12. The discussion could benefit from more detail on which specific antioxidants or
phytochemicals (e.g., polyphenols, flavonoids) in DASH are thought to contribute to its
protective effects.
13. Some sentences are overly complex and difficult to follow. Consider breaking them into
shorter, clearer statements.
Example:
"We considered each study once and followed all the procedures for the meta-analysis. We
performed subgroup analysis when necessary or when high grades of heterogeneity appeared
between studies."
Suggested Revision:
"Each study was included only once, following standardized meta-analysis procedures.
Subgroup analyses were conducted when significant heterogeneity was detected."
14. Were any sensitivity analyses conducted to determine if the exclusion of lower-quality
studies impacted the results?
15. How did the studies account for potential confounding factors such as BMI, smoking, alcohol
consumption, or family history of CRC?
16. Was adherence to the DASH diet assessed using standardized scoring methods across studies,
or were there variations in how adherence was measured?
17. Could differences in food availability and cultural dietary habits explain why some studies
found protective effects in men but not in women?
18. Were there any significant differences in findings based on study design (e.g., prospective
cohort studies vs. case-control studies)?
19. "This study grows more, the already significant body of evidence of lowering CRC risk
connected to compliance with the DASH dietary pattern."
Suggested Revision:
"This study adds to the growing body of evidence supporting the association between adherence
to the DASH dietary pattern and a reduced risk of colorectal cancer."
20. "The fact that the findings are homogenous between studies and across populations further
strengthens the recommendation for promoting the DASH diet as an effective dietary strategy
against CRC, probably reducing the burden of colorectal cancer; this might be useful in public
health initiatives and nutritional guidelines."
Suggested Revision:
"The consistency of findings across different studies and populations reinforces the
recommendation of the DASH diet as an effective dietary strategy for CRC prevention. These
findings may have significant implications for public health policies and nutritional guidelines
aimed at reducing the burden of colorectal cancer."
21. conclusion:
a. Consider briefly mentioning the need for future research (e.g., randomized controlled trials)
to strengthen causal inferences.
b. It might also be helpful to address whether the DASH diet should be integrated into dietary
recommendations for high-risk populations.