Table 1.
LFD efficacy in IBS.
| Trial Characteristics | Methods | Length of Follow-Up | Evaluated Parameters | Results | Grade of Evidence | |
|---|---|---|---|---|---|---|
| Short-term efficacy | ||||||
| McIntosh et al. [18] 2017 | LFD = 19 HFD = 18 Rome III |
Single blinded parallel | 3 weeks | IBS-SSS | Lower IBS-SSS in LFD group for gastrointestinal symptoms and abdominal pain. | Low |
| Ong et al. [26] 2010 | LFD or HFD IBS = 15 Healthy controls = 15 Rome III |
Single blinded, crossover | 2 days | Likert scale (GI symptoms severity) | IBS patients under HFD had more severe symptoms compared to those on LFD. | Low |
| Staudacher et al. [27] 2012 | LFD = 19 Habitual diet = 22 Rome III |
Single blinded, controlled | 4 weeks | GSRS BSC |
LFD group had better adequate symptom control, lower stool frequency, less abdominal pain, and less overall symptoms. | Low |
| Pedersen et al. [28] 2014 | LFD = 42 Probiotic = 41 Habitual diet = 40 Rome III |
Unblinded parallel | 6 weeks | IBS-SSS IBS-QOL |
Greater reduction in IBS-SSS in LFD group compared to habitual diet. No differences in IBS QOL. | Very low |
| Halmos et al. [29] 2014 | LFD or Typical (Australian) diet IBS = 30 Healthy controls = 8 Rome III |
Single blinded, controlled crossover | 21 days | VAS (GI symptoms severity) KSC FWC |
Lower VAS in LFD group. Lower stool frequency and lower KSC score in IBS-D during LFD. | Low |
| Bohn et al. [30] 2015 | LFD = 33 NICE = 34 Rome III |
Single blinded, multicentre parallel, controlled | 4 weeks | IBS-SSS HADS BSC Visceral sensitivity index |
IBS symptoms reduced in both diets, with no difference between groups. | Low |
| Chumpitazi et al. [31] 2015 | Pediatric patients LFD = 16 TACD = 17 Rome III |
Double blinded, crossover | 48 hours | Pain and stool diary Likert scale (Pain severity and associated GI symptoms) BSC |
Fewer abdominal pain episodes and less severity during LFD. Total composite GI score lower in LFD. | High |
| Eswaran et al. [32] 2016 | LFD = 45 mNICE = 39 Rome III |
Unblinded parallel | 4 weeks | AR BSC |
Greater reduction in abdominal pain and stool consistency in LFD group. No differences between groups regarding adequate symptom relief. | Very low |
| Laatikainen et al. [33] 2016 | Rye bread = 43 Low FODMAP rye bread = 44 Rome III |
Double blinded controlled crossover | 4 weeks | IBS-SSS VAS (GI symptoms severity) IBS-QOL |
Less abdominal pain, flatulence, stomach rumbling, and intestinal cramps in the Low-FODMAP rye bread group. | High |
| Staudacher et al. [34] 2017 | Sham diet/placebo = 27 Sham diet/probiotic = 26 LFD/placebo = 24 LFD/probiotic = 27 Rome III |
Single blinded, multicentre, placebo-controlled, | 4 weeks | GSRS IBS-SSS BSC IBS-QOL SF-36 |
Lower IBS-SSS and better IBS QOL in LFD group. | High |
| Hustoft et al. [35] 2017 | LFD and maltodextrin = 20 LFD and FOS = 20 Rome III |
Double blinded, placebo-controlled, crossover | 9 weeks | IBS-SSS VAS (associated symptoms) AR |
Lower IBS-SSS and more patients reporting symptom relief in the group supplemented with maltodextrin | High |
| Peters et al. [36] 2015 | LFD = 24 Hypnotherapy = 25 Combined = 25 Rome III |
Unblinded | 6 weeks | VAS (GI symptoms severity) IBS-QOL HADS STPI |
Lower VAS in LFD and hypnotherapy. IBS-QOL improved in all groups with no statistical differences. | Very low |
| Long-term efficacy | ||||||
| Staudacher et al. [37] 2011 | LFD = 43 NICE diet = 39 No aLFD Dietitian-led education |
Retrospective observational | 2–6 months | Likert scale (symptom changes and satisfaction with dietary advice) | LFD group reported improvement in bloating, abdominal pain, flatulence, nausea, and energy levels, and more satisfaction with the treatment. | Very low |
| Peters et al. [38] 2016 | LFD + aLFD = 24 Hypnotherapy = 25 Combination = 25 Dietitian-led education |
Unblinded, randomized | 6 weeks + 6 months | VAS IBS-SSS STPI HADS IBS-QOL |
Improvements in overall symptoms for hypnotherapy, LFD and combination, maintained at 6 months. Hypnotherapy superior regarding psychological indices. | Very low |
| Schumann et al. [39] 2018 | LFD for 12 weeks + aLFD = 29 Yoga 12 weeks = 30 Dietitian-led education |
Single blinded randomized controlled trial | 6 months | IBS-SSS IBS-QOL SF-36 HADS CPSS PSQ BAQ BRS AR |
IBS-SSS scores decreased both for LFD and yoga, with no statistically significant group differences. HADS scores were lower in yoga group, especially on the subscale for anxiety. | Low |
| de Roest et al. [40] 2013 | LFD = 90 Dietitian-led education |
Prospective observational | 15.7 (±9.0) months | GI symptom rating scale Likert scale (symptoms intensity and adherence) |
Positive change in most of the investigated symptoms, including abdominal pain, bloating, flatulence, and diarrhea. Fructose malabsorption was associated with response to the diet. 75.6% were adherent to LFD. | Very low |
| Maagaard et al. [41] 2016 | IBS = 131 IBD = 49 LFD for 6-8 weeks + aLFD = 180 Dietitian-led education |
Retrospective cross-sectional | 16 months (range: 2–80) | VAS FARS BSC IBS-SSS IBS-QOL SIBDQ |
Partial or full efficacy of bloating and abdominal pain. One third were adherent to the diet. LFD was reported to be more expensive and complicated than usual diet. | Very low |
| O’Keeffe et al. [42] 2018 | NICE IBS criteria LFD for 6 weeks + aLFD = 103 Dietitian-led education |
Prospective observational | 6–18 months | Global symptom response GSRS BSC Likert scale (acceptability and impact on daily life) |
Abdominal pain, bloating and flatulence decreased at long-term follow up. Satisfactory symptom relief was reported at follow-up. aLFD was found to be more expensive and difficult than habitual diet. | Very low |
| Harvie et al. [43] 2017 | LFD = 23 Habitual diet = 27 aLFD = 23 LFD = 27 Dietitian-led education |
Randomized, parallel, cross-over | 6 months | IBS-SSS IBS-QOL |
Lower reduction of IBS-SSS and better QoL in LFD (3 months) and sustained by aLFD (6 months). | Low |
| Weynants et al. [44] 2019 | LFD for 6–8 weeks + aLFD = 90 Dietitian-led education |
Retrospective cross-sectional | 49–168 weeks | IBS-QOL IBS-SSS Self-developed adherence and symptoms questionnaire |
Patients who still followed the diet had less severe abdominal pain. 80% of patients were adherent to the LFD. No significant difference in QOL was found. | Very low |
aLFD: Adapted LFD; AR: Adequate symptom Relief; BAQ: Body Awareness Questionnaire; BRS: Body Responsiveness Questionnaire; BSC: Bristol Stool Chart; CPSS: Cohen Perceived Stress Scale; FARS: FODMAP Adherence Report Scale; FODMAPs: Fermentable Oligo-, Di- and Monosaccharides and Polyols; FOS: Fructooligosaccharides; FWC: Fecal Water Content; GI: Gastrointestinal; GSRS: GI Symptoms Rating Scale; HADS: Hospital Anxiety and Depression Scale; HFD: High FODMAP Diet; IBD: Inflammatory Bowel Disease; IBS: Irritable Bowel Syndrome; IBS-D: Diarrhea predominant Irritable Bowel Syndrome; IBS-QOL: Irritable Bowel Syndrome Quality of Life; IBS-SSS: Irritable Bowel Syndrome Severity Scoring System; KSC: King’s Stool Chart; LFD: Low-FODMAP Diet; LGG: Lactobacillus rhamnosus GG; mNICE: Modified National Institute for Health and Clinical Excellence; NICE: National Institute for Health and Clinical Excellence; n.a.: not assessed; PSQ: Perceived Stress Questionnaire; SF-36: Short Form Health Survey; SIBDQ: Short IBD Questionnaire; STPI: State-Trait Personality Inventory; TACD: Typical American Childhood Diet; VAS: Visual Analogue Scale.