The low-bacterial diet (LBD) is a widely used dietary regimen to reduce the risk of food-borne infections in patients with neutropenic cancer, but its role is controversial due to its unclear benefits. The purpose of this study was to provide an updated analysis of the available evidence on the efficacy of the LBD to reduce the risk of infections, mortality rates, and quality of life (QoL) in neutropenic patients with cancer. A systematic literature search was conducted in the biomedical databases Cochrane Library, PubMed, CINHAL, and EMBASE. The process of the screening, selection, inclusion of articles, and assessment of risk of bias and methodological quality was conducted by two reviewers. Of the 1985 records identified, 12 were included. The LBD demonstrated heterogeneity in definition, composition, and initiation timing; moreover, the LBD did not demonstrate a reduction in infection and mortality rates compared to a free diet, showing a negative correlation with quality of life. The LBD, in addition to not bringing benefits in terms of reductions in infection and mortality rates, has been shown to worsen the quality of life due to the reduced palatability and limited variety of the food supply, negatively impacting nutritional status.

BACKGROUND: Multiple studies have questioned the benefit of neutropenic diets in decreasing infections in patients with cancer, but recent surveys showed that such diets are still prescribed. In this study, we sought to evaluate the effectiveness of neutropenic diet in decreasing infection and mortality in neutropenic patients with cancer with neutropenia. This review is an update of a previously published systematic review.
METHODS: We searched different databases to identify comparative studies that investigated the effect of neutropenic diet compared with regular diet in neutropenic adults and children with cancer. We conducted random-effects meta-analyses using the Der-Simonian and Laird method to pool treatment effects from included studies. Outcomes of interest were mortality, bacteremia/fungemia, major infections, quality of life, and the composite outcome for neutropenic fever and/or infection.
RESULTS: We included six studies (five randomised) with 1116 patients, with 772 (69.1%) having underwent haematopoietic cell transplant. There was no statistically significant difference between neutropenic diet and regular diet in the rates of major infections (relative risk [RR] 1.16; 95% CI 0.94 to 1.42) or bacteremia/fungemia (RR 0.96; 95% CI 0.60 to 1.53). In haematopoietic cell transplant patients, neutropenic diet was associated with a slightly higher risk of infections (RR 1.25; 95% CI 1.02 to 1.54). No difference in mortality was seen between neutropenic diet and regular diet (RR 1.08, 95% CI 0.78 to 1.50).
CONCLUSIONS: There is currently no evidence to support the use of neutropenic diet or other food restrictions in neutropenic patients with cancer. Patients and clinicians should continue to follow the safe food-handling guidelines as recommended by the U.S. Food and Drug Administration.