scholarly journals A Preparatory Study for a Randomized Controlled Trial of Dietary Fiber Intake During Adult Pelvic Radiotherapy

2021 ◽  
Vol 8 ◽  
Author(s):  
Rebecca Ahlin ◽  
Karin Bergmark ◽  
Cecilia Bull ◽  
Sravani Devarakonda ◽  
Rikard Landberg ◽  
...  
Keyword(s):  
Dietary Fiber ◽  
Participation Rate ◽  
Dropout Rate ◽  
Control Group ◽  
Powder Form ◽  
Fiber Intake ◽  
Pelvic Radiotherapy ◽  
Fecal Samples ◽  
Randomized Controlled ◽  
Dietary Fiber Intake

Background: Patients undergoing pelvic radiotherapy are often advised to omit fiber-rich foods from their diet to reduce the adverse effects of treatment. Scientific evidence supporting this recommendation is lacking, and recent studies on animals and humans have suggested that there is a beneficial effect of dietary fiber for the alleviation of symptoms. Randomized controlled studies on dietary fiber intake during pelvic radiotherapy of sufficient size and duration are needed. As preparation for such a large-scale study, we evaluated the feasibility, compliance, participation rate, and logistics and report our findings here in this preparatory study.Methods: In this preparatory study of a fiber intervention trial, Swedish gynecological cancer patients scheduled for radiotherapy were recruited between January 2019 and August 2020. During the intervention, the participants filled out questionnaires and used an application. They also consumed a fiber supplement at first in powder form, later in capsules. Blood- and fecal samples were collected. The study is registered in clinicaltrials.gov (https://clinicaltrials.gov/ct2/show/NCT04534075?cond=fidura&draw=2&rank=1).Results: Among 136 approached patients, 57 started the study and the participation rate for primary outcomes was 63% (third blood sample) and 65% (third questionnaire). Barely half of the participants provided fecal samples. Providing concise and relevant information to the patients at the right time was crucial in getting them to participate and stay in the study. The most common reasons for declining participation or dropping out were the expected burden of radiotherapy or acute side effects. Tailoring the ambition level to each patient concerning the collection of data beyond the primary endpoints was an important strategy to keep the dropout rate at an acceptable level. Using capsules rather than psyllium in powder form made it much easier to document intake and to create a control group. During the course of the preparatory study, we improved the logistics and for the last 12 participants included, the participation rate was 100% for the earliest primary outcome.Conclusion: A variety of adjustments in this preparatory study resulted in an improved participation rate, which allowed us to set a final protocol and proceed with the main study.

EFFECTS OF DIETARY FIBER INTAKE IN CHEMOTHERAPY-INDUCED MUCOSITIS IN MURINE MODEL

2020 ◽  
pp. 1-34
Author(s):  
B Gallotti ◽  
I Galvao ◽  
G Leles ◽  
MF Quintanilha ◽  
RO Souza ◽  
...  
Keyword(s):  
Dietary Fiber ◽  
Murine Model ◽  
Short Chain Fatty Acids ◽  
Normal Diet ◽  
Control Group ◽  
Fiber Intake ◽  
Gut Permeability ◽  
High Fiber ◽  
Dietary Fiber Intake ◽  
High Doses

Abstract Mucositis is an inflammation of the gastrointestinal mucosa resulting from high-doses of radio/chemotherapy treatment and may lead to interruption of antineoplasic therapy. Soluble fibers, like pectin, increase short-chain fatty acids (SCFA) production that play a role in gut homeostasis and inflammation suppression. Due to the properties of pectin, the aim of this study was to evaluate the effect of a high-fiber diet on chemotherapy-induced mucositis in a murine model. C57/BL6 mice received control (AIN93M), high-fiber (HF), low/zero fiber (LF) diets for 10 days prior the mucositis challenging with irinotecan (75 mg/kg); or, they were treated with acetate added to drinking water 5 days prior and during the mucositis induction. Mice that received HF diet showed decreased immune cells influx and improved histopathological parameters in the intestine, compared to mice that received normal diet. Furthermore, HF diet decreased intestinal permeability induced in the mucositis model when compared to the control group. This effect was not observed in the acetate alone, which did not improve gut permeability. For instance, mice that received LF diet worsened gut permeability, compared with mice that received normal diet and mucositis. The effects of the HF and LF diets were shown to modulate the intestinal microbiota, in which the LF diet increased the levels of Enterobacteriaceae, a group associated with gut inflammation, whereas the HF diet decreased this group and increased Lactobacillus and Bifidobaterium (SCFA producers) levels. In conclusion, the results demonstrated the importance of dietary fiber intake in the modulation of gut microbiota composition and homeostasis maintenance during mucositis in this model.

scholarly journals A randomized controlled trial of dietary fiber intake on serum lipids

2005 ◽  
Vol 60 (1) ◽  
pp. 62-68 ◽  
Author(s):  
J Chen ◽  
J He ◽  
R P Wildman ◽  
K Reynolds ◽  
R H Streiffer ◽  
...  
Keyword(s):  
Randomized Controlled Trial ◽  
Dietary Fiber ◽  
Serum Lipids ◽  
Controlled Trial ◽  
Fiber Intake ◽  
Randomized Controlled ◽  
Dietary Fiber Intake

scholarly journals Effect of chicory inulin-type fructan–containing snack bars on the human gut microbiota in low dietary fiber consumers in a randomized crossover trial

2020 ◽  
Vol 111 (6) ◽  
pp. 1286-1296 ◽  
Author(s):  
Raylene A Reimer ◽  
Adriana Soto-Vaca ◽  
Alissa C Nicolucci ◽  
Shyamchand Mayengbam ◽  
Heekuk Park ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Dietary Fiber ◽  
Low Dose ◽  
Healthy Adults ◽  
Control Group ◽  
Fiber Intake ◽  
Moderate Dose ◽  
Double Blind ◽  
Dietary Fiber Intake ◽  
Gi Symptoms

Abstract Background The low intake of dietary fiber compared to recommended amounts has been referred to as the dietary fiber gap. The addition of fiber to snack foods could favorably alter gut microbiota and help individuals meet intake recommendations. Objectives Our objective was to examine the effect of low- and moderate-dose fiber-containing snack bars, comprising mainly chicory root inulin-type fructans (ITF), on gut microbiota in healthy adults with habitual low dietary fiber intake using 16S ribosomal RNA–based approaches. Methods In 2 separate 4-wk, placebo-controlled, double-blind, crossover trials, 50 healthy adults with low dietary fiber intake were randomly assigned to receive isocaloric snack bars of either moderate-dose fiber (7 g/d) or control in Trial 1 (n = 25) or low-dose fiber (3 g/d) or control in Trial 2 (n = 25), with 4-wk washout periods. Fecal microbiota composition and inferred function, fecal SCFA concentration, gastrointestinal (GI) symptoms, dietary intake, and quality of life were measured. Results Compared with the control group, the moderate-dose group showed significant differences across multiple microbial taxa, most notably an increased relative abundance of the Bifidobacterium genus from (mean ± SEM) 5.3% ± 5.9% to 18.7% ± 15.0%. With low-dose ITF, significant increases in Bifidobacterium were no longer present after correction for multiple comparisons but targeted analysis with qPCR showed a significant increase in Bifidobacterium. Predictive functional profiling identified changes in predicted function after intake of the moderate- but not the low-dose bar. Fecal SCFAs were affected by time but not treatment. There were no between-group differences in GI symptoms. Importantly, fiber intake increased significantly with the moderate- and low-dose bars. Conclusions In healthy adults, adding 3 or 7 g ITF to snack bars increased Bifidobacterium, a beneficial member of the gut microbial community. The addition of ITF to food products could help reduce the dietary fiber gap prevalent in modern life. This trial was registered at clinicaltrials.gov as NCT03042494.

scholarly journals Dietary fiber intake from fresh and preserved food and risk of nasopharyngeal carcinoma: observational evidence from a Chinese population

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Zhi-Ming MAI ◽  
Roger Kai-Cheong NGAN ◽  
Dora Lai-Wan KWONG ◽  
Wai-Tong NG ◽  
Kam-Tong Yuen ◽  
...  
Keyword(s):  
Nasopharyngeal Carcinoma ◽  
Dietary Fiber ◽  
Dose Response ◽  
Sun Exposure ◽  
Fiber Intake ◽  
Total Dietary Fiber ◽  
Dietary Fiber Intake ◽  
Fresh Vegetables ◽  
Incident Cases

Abstract Background The role of dietary fiber intake on risk of nasopharyngeal carcinoma (NPC) remains unclear. We examined the associations of dietary fiber intake on the risk of NPC adjusting for a comprehensive list of potential confounders. Methods Using data from a multicenter case-control study, we included 815 histologically confirmed NPC incident cases and 1502 controls in Hong Kong, China recruited in 2014–2017. Odds ratios (ORs) of NPC (cases vs controls) for dietary fiber intake from different sources at different life periods (age 13–18, age 19–30, and 10 years before recruitment) were evaluated using unconditional logistic regression, adjusting for sex, age, socioeconomic status, smoking and drinking status, occupational hazards, family history of cancer, salted fish, and total energy intake in Model 1, Epstein-Barr virus viral capsid antigen serological status in Model 2, and duration of sun exposure and circulating 25-hydroxyvitamin D in Model 3. Results Higher intake of total dietary fiber 10 years before recruitment was significantly associated with decreased NPC risk, with demonstrable dose-response relationship (P-values for trend = 0.001, 0.020 and 0.024 in Models 1–3, respectively). The adjusted ORs (95% CI) in the highest versus the lowest quartile were 0.51 (0.38–0.69) in Model 1, 0.48 (0.33–0.69) in Model 2, and 0.48 (0.33–0.70) in Model 3. However, the association was less clear after adjustment of other potential confounders (e.g. EBV) in the two younger periods (age of 13–18 and 19–30 years). Risks of NPC were significantly lower for dietary fiber intake from fresh vegetables and fruits and soybean products over all three periods, with dose-response relationships observed in all Models (P-values for trend for age 13–18, age 19–30 and 10 years before recruitment were, respectively, 0.002, 0.009 and 0.001 for Model1; 0.020, 0.031 and 0.003 for Model 2; and 0.022, 0.037 and 0.004 for Model 3). No clear association of NPC risk with dietary fiber intake from preserved vegetables, fruits and condiments was observed. Conclusion Our study has shown the protective role of dietary fiber from fresh food items in NPC risk, but no association for total dietary fiber intake was observed, probably because total intake also included intake of preserved food. Further studies with detailed dietary information and in prospective settings are needed to confirm this finding, and to explore the possible underlying biological mechanisms.

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