High-Fat Diet as a Risk Factor for Breast Cancer: A Meta-Analysis

Abstract

High-fat diets have been identified as a major cause of obesity and a potential risk factor for breast cancer. Fat tissue, also known as adipose tissue, produces an excess of estrogen, which has been linked to an increased risk of breast cancer. Determining the impact of HFDs in the development and progression of breast cancer is essential, as it will enable us to identify the role of dietary modification in preventing and managing the disease. The impact of a high-fat diet (HFD) on the development of breast cancer in humans has yet to be fully explained, as very few human studies are available to effectively analyze the effect fatty food has on breast cancer development. This meta-analysis, therefore, seeks to determine the strength of association, if any, between HFD and an increased risk of breast cancer development. This research will help inform good eating habits, potentially reducing the disease's incidence and outcome. This meta-analysis examined eight (8) papers from various nations examining the effect of a high-fat diet as a risk factor for breast cancer development between 2010 and 2020. The study employed the multivariable-adjusted hazard ratio (H.R.), odds ratio (OR), or relative risk (R.R.) from the studies. Breast cancer cases were histologically and radiologically confirmed in the studies evaluated, and validated food frequency questionnaires were used to assess their dietary patterns. This metanalysis study found a substantial link between a high-fat diet and an increased risk of breast cancer, with statistically significant results (I² = 93.38%, p0.05). Changes in dietary fat consumption may thus help mitigate some of the unfavorable consequences of breast cancer and survival. Even if further research is needed to support this assertion, the findings are compelling enough to advocate for low-fat, healthy diets to avoid breast cancer.

Keywords: breast cancer; breast cancer biology; cancer; causes of breast cancer; fat diet; high-fat diet; metastatic breast disease; mortality of breast cancer; obesity and breast cancer; risk factors for breast cancer.

Figure 1. PRISMA flow for inclusion and exclusion criteria

PRISMA: Preferred Reporting Items for Systematic Reviews and Meta-Analyses

Figure 2. A forest plot of all studies weighted in square sizes demonstrating a strong association between a high-fat diet and the incidence of breast cancer

Fung et al. [8], Kruk and Marchlewicz [9], Jones et al. [10], Berkey et al. [11], Dydjow-Bendek and Zagoźdźon [12], Khankari et al. [13], Link et al. [14], Turati et al. [15] REML: restricted maximum likelihood

Figure 3. A forest plot of all studies demonstrating a strong association between a high-fat diet and the incidence of breast cancer

Fung et al. [8], Kruk and Marchlewicz [9], Jones et al. [10], Berkey et al. [11], Dydjow-Bendek and Zagoźdźon [12], Khankari et al. [13], Link et al. [14], Turati et al. [15] REML: restricted maximum likelihood

Figure 4. Forest plot of the case-control versus cohort studies

Fung et al. [8], Kruk and Marchlewicz [9], Jones et al. [10], Berkey et al. [11], Dydjow-Bendek and Zagoźdźon [12], Khankari et al. [13], Link et al. [14], Turati et al. [15] REML: restricted maximum likelihood

Figure 5. Forest plot of the cohort studies (square weighted)

Berkey et al. [11], Dydjow-Bendek and Zagoźdźon [12], Link et al. [14] REML: restricted maximum likelihood

Figure 6. Comparing case-control studies to cohort studies using a forest plot, the cohort studies showed a stronger correlation

Fung et al. [8], Kruk and Marchlewicz [9], Jones et al. [10], Khankari et al. [13], Turati et al. [15] REML: restricted maximum likelihood