Table 4. Study characteristics and AMSTAR quality appraisal for systematic reviews with meta-analysis.
RR - Relative risk
CI - Confidence interval
p - P-factor
| Author/Year of publication | Study | Number of studies included in the meta-analysis | Study population size (Women) | Conclusion | Results | AMSTAR score |
| Lodi et al. [17] (2022) | Lipid Intake and Breast Cancer Risk: Is There a Link? A New Focus and Meta-Analysis | 44 studies (28 case-control and 16 cohort studies) | 1,185,896 | A weak association between breast cancer risk in postmenopausal women and a high saturated fat diet was found. | Case-control studies (RR = 1.12, 95% CI = 1.03–1.21, p = 0.006); cohort studies (RR = 1.01, 95% CI = 0.85–1.19, p = 0.93). | 13/16, Good |
| Yongjo kim et al. [6] (2020) | Association between dietary fat intake and mortality from all causes, cardiovascular disease, and cancer: A systematic review and meta-analysis of prospective cohort studies | 19 cohort studies | 1,013,273 | Diets high in saturated fat had a high all-cause mortality rate, including cancer. | Every 5% increase in saturated fat intake increases the risk of cancer mortality by 4% (RR = 0.93; 95% CI = 0.89-0.97). | 14/16, Good |
| Brennan et al. [18] (2017) | Dietary fat and breast cancer mortality: A systematic review and meta-analysis | 15 prospective cohort studies | 29241 | Saturated fat intake has a negative association with the survival of breast cancer patients. | Women in the highest vs. lowest category of intake of saturated fat had a higher rate of breast cancer-specific death (HR = 1.51, 95% CI = 1.09-2.09, p 0.01). | 14/16, Good |
| Shetty et al. [7] (2019) | Breast Cancer and Dietary Fat Intake: A correlational study | 88 cross-sectional studies | Not available | Increased total fat consumption increases the risk of breast cancer. | A statistically significant correlation (p<0.001) of more than 0.6 between fat consumption and crude breast cancer incidence rates was found. | 12/16, Good |
| Smith-Warner et al. [19] (2001) | Types of dietary fat and breast cancer: a pooled analysis of cohort studies | Eight prospective cohort studies | 351,821 | Weak positive association for substituting saturated fat for carbohydrates in breast cancer risk. | (RR = 1.09 for an increment of 5% of energy from saturated fat, 95% CI = 1.00–1.19) | 12/16, Good |
| Boyd et al. [20] (2003) | Dietary fat and breast cancer risk revisited: a meta-analysis of the published literature | 31 case-control and 14 cohort studies | 603,795 | In case-control and cohort studies, total fat and saturated fat were significantly associated with breast cancer risk. | Total fat: RR=1.13 (95% CI= 1.03–1.25) Saturated fat: RR = 1.19 (95% CI = 1.06–1.35). | 13/16, Good |
| Xia et al. [21] (2015) | Meta-Analysis of Saturated Fatty Acid Intake and Breast Cancer Risk | 28 case-control and 24 cohort studies | ~50,000 | Dietary saturated fat is linked with breast cancer risk. | Case-control studies (high vs. low intake): RR = 1.18 (95% CI = 1.03-1.34); cohort studies (high vs. low intake, RR = 1.04 (95% CI = 0.97-1.11). | 13/16, Good |