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A Randomized, Crossover Trial of a Nutritional Intervention for Rheumatoid Arthritis
Abstract
To investigate the effects of a dietary intervention on arthritis pain and disease severity, 44 adults previously diagnosed with rheumatoid arthritis were randomly assigned to a Diet phase (vegan diet for 4 weeks, elimination of additional foods for 3 weeks, and then reintroduction of the eliminated foods individually over 9 weeks) or a Supplement (placebo) phase for 16 weeks. After a 4-week washout, they then switched to the opposite phase. The Disease Activity Score-28 (DAS28) decreased from 4.5 to 2.5 (P < .001) in the Diet phase and from 3.2 to 2.9 (P = .41) in the Supplement phase (between-group P = .01). The mean number of swollen joints decreased from 7.0 to 3.3 in the Diet phase (P = .03) and increased from 4.7 to 5 in the Supplement phase (P = .63; between-group P = .047).
In a subanalysis excluding individuals who increased medications during the study, DAS28 decreased 1.9 points in the Diet phase (P = .003) and .4 points in the Supplement phase (P = .27; between-group P = .04). In a further subanalysis limited to participants making no medication changes, DAS28 decreased 1.5 points in the Diet phase (P = .009) and .3 points in the Supplement phase (P = .40, between-group P = .11). We conclude that the dietary intervention was associated with symptomatic improvements. TRIAL REGISTRATION: Clinicaltrials.gov NCT01544101, NCT01700881, NCT03417648, and NCT03580681
Context
Rheumatoid arthritis (RA) is an autoimmune disease that leads to chronic inflammation and joint damage. Various plant-based diets are thought to have effects on RA symptoms and disease activity.
Objective
Relevant literature on the effect of different types of plant-based diets on RA was reviewed.
Data Sources
A systematic search was conducted using the Web of Science, PubMed, Scopus, and Cochrane databases and following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.
Data Extraction
Articles on observational and interventional human studies carried out in the adult population and published in English between February 2013 and April 2023 were eligible for inclusion. Articles reporting on studies performed in populations under 18 years of age, with unclear methods and results, or for which the full text was unavailable were excluded. The risk of bias in the selected studies was assessed using the Joanna Briggs Institute checklists.
Data Analysis
Of 547 screened articles, 15 were included, comprising 4 cross-sectional, 2 cohort, and 9 randomized controlled trials. These studies examined the effects of various diets, including the Mediterranean, low-fat high-carbohydrate, anti-inflammatory, and vegan, on RA. Results indicate adherence to plant-based diets generally reduced disease severity and improved dietary intake, physical activity, body weight, and key clinical markers such as the Disease Activity Score-28, Visual Analog Scale score, Health Assessment Questionnaire Disability Index, erythrocyte sedimentation rate, and C-reactive protein level in patients with in RA.
Conclusions
Most of the studies suggested the Mediterranean diet may positively affect the severity of RA. However, the included studies show heterogeneity. Therefore, more randomized controlled studies are needed in this area to increase understanding of the effect of diet on RA and facilitate the implementation of strategies to prevent RA.
Systematic Review Registration
PROSPERO registration no. CRD42023420577.
Rheumatoid arthritis is a debilitating inflammatory condition which has a high disease burden. While there is emerging evidence that certain foods and diets could have anti-inflammatory properties and there are published ‘anti-inflammatory’ diets, there is very little understanding of patient beliefs and perceptions about the impact of diet on symptom management or attitudes to particular dietary interventions. This scoping review aims to summarize the existing literature around the beliefs that patients with rheumatoid arthritis hold regarding the impact of diet on disease activity and joint pain. It also examines the current state of evidence regarding the impact of specific dietary interventions on patient reported and objective parameters of RA disease activity. A search was conducted across seven databases for studies which included reporting on dietary beliefs related to disease management or investigations on the effect of particular diets on disease activity or joint pain. Articles were excluded if they examined extracted compounds or individual dietary supplements. Included studies were synthesized narratively. We retrieved 25,585 papers from which 68 were included in this review: 7 assessed dietary beliefs, 61 explored dietary interventions. The available literature on patient beliefs has been largely limited to quantitative studies with limited qualitative exploration. The Mediterranean, fasting and vegan diets appear to have the most benefit with regards to rheumatoid arthritis outcomes for patients. Research which examines RA patient’s beliefs and attitudes about the impact of diet on their RA symptoms and disease is currently lacking.
Objectives
In two randomised controlled trials, the Plants for Joints (PFJ) multidisciplinary lifestyle intervention reduced signs and symptoms of rheumatoid arthritis (RA), or metabolic syndrome-associated hip or knee osteoarthritis (MSOA) compared with usual care. The current study investigated long-term outcomes.
Methods
After completion of two 16-week trials in people with (1) RA or (2) MSOA, control groups switched to the active PFJ intervention. At the end of the intervention, all participants were followed up in a 1-year observational extension study. Primary outcomes were 28-joint Disease Activity Score (DAS28) (RA) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) (MSOA). Secondary outcomes included body composition, metabolic outcomes, medication changes and intervention adherence. An intention-to-treat analysis with a linear mixed model was used to analyse within-group changes.
Results
65 (84%) of 77 RA participants and 49 (77%) of 64 MSOA participants completed the extension study. The effects of the PFJ intervention were replicated in the original control groups and sustained within the RA group a year after intervention completion (mean DAS28 –0.9 points; p<0.001), while in the MSOA group mean WOMAC increased towards but remained well under the starting value (–7.8 points, p<0.001). Improvements in C-reactive protein, waist circumference (RA and MSOA); low-density lipoprotein cholesterol (RA); and weight, haemoglobin A1c, blood pressure (MSOA) were also sustained. Participants had a net decrease of medication, and intervention adherence was largely sustained.
Conclusions
A year after the PFJ lifestyle intervention, improvements of disease activity and metabolic outcomes within RA and MSOA groups were largely sustained and related to sustained adherence, with a net decrease of medication.
Trial registration numbers
NL7800, NL7801.
Rheumatoid arthritis (RA), a chronic inflammatory autoimmune disease, affects roughly 1% of the world's population. RA pathogenesis remains unclear, but genetic factors account for 50–60% of the risk while the remainder might be linked to modifiable factors, such as infectious diseases, tobacco smoking, gut bacteria, and nutrition. Dietary triggers may play an inciting role in the autoimmune process, and a compromised intestinal barrier may allow food components or microorganisms to enter the blood stream, triggering inflammation. In addition, excessive body weight may affect pharmacotherapy response and the likelihood of disease remission, as well as the risk of disease mortality. Evidence suggests that changes in diet might play an important role in RA management and remission. Several studies have shown improvements in RA symptoms with diets excluding animal products. Studies have also shown that dietary fiber found in these plant-based foods can improve gut bacteria composition and increase bacterial diversity in RA patients, thus reducing their inflammation and joint pain. Although some of the trigger foods in RA patients are individualized, a vegan diet helps improve symptoms by eliminating many of these foods. This review examines the potential role of a plant-based diet in mediating RA symptoms. Further research is needed to test the effectiveness of plant-based diets on joint pain, inflammation, and quality of life in patients with RA.
Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease that primarily affects the lining of the synovial joints and is associated with progressive disability, premature death, and socioeconomic burdens. A better understanding of how the pathological mechanisms drive the deterioration of RA progress in individuals is urgently required in order to develop therapies that will effectively treat patients at each stage of the disease progress. Here we dissect the etiology and pathology at specific stages: (i) triggering, (ii) maturation, (iii) targeting, and (iv) fulminant stage, concomitant with hyperplastic synovium, cartilage damage, bone erosion, and systemic consequences. Modern pharmacologic therapies (including conventional, biological, and novel potential small molecule disease-modifying anti-rheumatic drugs) remain the mainstay of RA treatment and there has been significant progress toward achieving disease remission without joint deformity. Despite this, a significant proportion of RA patients do not effectively respond to the current therapies and thus new drugs are urgently required. This review discusses recent advances of our understanding of RA pathogenesis, disease modifying drugs, and provides perspectives on next generation therapeutics for RA.
The notion that dietary factors may influence rheumatoid arthritis (RA) has been a part of the folklore of the disease, but scientific support for this has been sparse. In a controlled, single-blind trial we tested the effect of fasting for 7-10 d, then consuming an individually adjusted, gluten-free, vegan diet for 3.5 mo, and then consuming an individually adjusted lactovegetarian diet for 9 mo on patients with RA. For all clinical variables and most laboratory variables measured, the 27 patients in the fasting and vegetarian diet groups improved significantly compared with the 26 patients in the control group who followed their usual omnivorous diet throughout the study period. One year after the patients completed the trial, they were reexamined. Compared with baseline, the improvements measured were significantly greater in the vegetarians who previously benefited from the diet (diet responders) than in diet nonresponders and omnivores. The beneficial effect could not be explained by patients' psychologic characteristics, antibody activity against food antigens, or changes in concentrations of prostaglandin and leukotriene precursors. However, the fecal flora differed significantly between samples collected at time points at which there was substantial clinical improvement and time points at which there were no or only minor improvements. In summary, the results show that some patients with RA can benefit from a fasting period followed by a vegetarian diet. Thus, dietary treatment may be a valuable adjunct to the ordinary therapeutic armamentarium for RA.
Clinical experience suggests that fasting followed by vegetarian diet may help patients with rheumatoid arthritis (RA). We reviewed the available scientific evidence, because patients frequently ask for dietary advice, and exclusive pharmacological treatment of RA is often not satisfying. Fasting studies in RA were searched in MEDLINE and by checking references in relevant reports. The results of the controlled studies which reported follow-up data for at least three months after fasting were quantitatively pooled. Thirty-one reports of fasting studies in patients with RA were found. Only four controlled studies investigated the effects of fasting and subsequent diets for at least three months. The pooling of these studies showed a statistically and clinically significant beneficial long-term effect. Thus, available evidence suggests that fasting followed by vegetarian diets might be useful in the treatment of RA. More randomised long-term studies are needed to confirm this view by methodologically convincing data.
Physical inactivity is a global concern, but diverse physical activity measures in use prevent international comparisons. The International Physical Activity Questionnaire (IPAQ) was developed as an instrument for cross-national monitoring of physical activity and inactivity.
Between 1997 and 1998, an International Consensus Group developed four long and four short forms of the IPAQ instruments (administered by telephone interview or self-administration, with two alternate reference periods, either the "last 7 d" or a "usual week" of recalled physical activity). During 2000, 14 centers from 12 countries collected reliability and/or validity data on at least two of the eight IPAQ instruments. Test-retest repeatability was assessed within the same week. Concurrent (inter-method) validity was assessed at the same administration, and criterion IPAQ validity was assessed against the CSA (now MTI) accelerometer. Spearman's correlation coefficients are reported, based on the total reported physical activity.
Overall, the IPAQ questionnaires produced repeatable data (Spearman's rho clustered around 0.8), with comparable data from short and long forms. Criterion validity had a median rho of about 0.30, which was comparable to most other self-report validation studies. The "usual week" and "last 7 d" reference periods performed similarly, and the reliability of telephone administration was similar to the self-administered mode.
The IPAQ instruments have acceptable measurement properties, at least as good as other established self-reports. Considering the diverse samples in this study, IPAQ has reasonable measurement properties for monitoring population levels of physical activity among 18- to 65-yr-old adults in diverse settings. The short IPAQ form "last 7 d recall" is recommended for national monitoring and the long form for research requiring more detailed assessment.
To validate and compare the definition of the Disease Activity Score 28 based on C-reactive protein (DAS28 (CRP)) to the definition based on erythrocyte sedimentation rate (ESR).
Data were analysed from two randomised, double-blind, placebo-controlled trials of abatacept of 6-month and 12-month duration in patients with rheumatoid arthritis. European League Against Rheumatism (EULAR) response criteria and the proportion of patients in remission (DAS28 <2.6) based on the two DAS28 definitions were examined. Trends in radiographic progression (erosion score, joint space narrowing score and total score) and physical function (Health Assessment Questionnaire Disability Index (HAQ-DI)) across the EULAR responder states (none, moderate and good) were analysed.
There was general agreement in determining the EULAR responder state using both DAS28 definitions (kappa = 0.80, 95% CI 0.76 to 0.83). Overall, there was 82.4% agreement on the EULAR response criteria; when disagreements occurred, the DAS28 (CRP) yielded a better EULAR response more often then DAS28 (ESR) (12.6% vs 4.9%, respectively). There was also agreement in determining remission: kappa = 0.69 (95% CI 0.60 to 0.78). Radiographic progression decreased in patients treated with abatacept across EULAR states (from none to moderate to good) based on both definitions. For patients treated with placebo, the trend was not as pronounced, with radiographic scores higher for moderate vs non-responders. For physical function, similar trends were observed across the EULAR states for both DAS28 definitions.
The DAS28 (CRP) has been validated against radiographic progression and physical function. While the DAS28 (CRP) yielded a better EULAR response more often than the DAS28 (ESR), the validation profile was similar to the DAS28 (ESR), indicating that both measures are useful for assessing disease activity in patients with rheumatoid arthritis.
Objectives
To provide the level and trends of prevalence, incidence and disability adjusted life years (DALYs) for rheumatoid arthritis (RA) in 195 countries from 1990 to 2017 by age, sex, Socio-demographic Index (SDI; a composite of sociodemographic factors) and Healthcare Access and Quality (an indicator of health system performance) Index.
Methods
Data from the Global Burden of Diseases, Injuries, and Risk Factors study (GBD) 2017 were used. GBD 2017 modelled the burden of RA for 195 countries from 1990 to 2017, through a systematic analysis of mortality and morbidity data to estimate prevalence, incidence and DALYs. All estimates were presented as counts and age-standardised rates per 100 000 population, with uncertainty intervals (UIs).
Results
Globally, the age-standardised point prevalence and annual incidence rates of RA were 246.6 (95% UI 222.4 to 270.8) and 14.9 (95% UI 13.3 to 16.4) in 2017, which increased by 7.4% (95% UI 5.3 to 9.4) and 8.2% (95% UI 5.9 to 10.5) from 1990, respectively. However, the age-standardised rate of RA DALYs per 100 000 population was 43.3 (95% UI 33.0 to 54.5) in 2017, which was a 3.6% (95% UI −9.7 to 0.3) decrease from the 1990 rate. The age-standardised prevalence and DALY rates increased with age and were higher in females; the rates peaked at 70–74 and 75–79 age groups for females and males, respectively. A non-linear association was found between age-standardised DALY rate and SDI. The global age-standardised DALY rate decreased from 1990 to 2012 but then increased and reached higher than expected levels in the following 5 years to 2017. The UK had the highest age-standardised prevalence rate (471.8 (95% UI 428.9 to 514.9)) and age-standardised incidence rate (27.5 (95% UI 24.7 to 30.0)) in 2017. Canada, Paraguay and Guatemala showed the largest increases in age-standardised prevalence rates (54.7% (95% UI 49.2 to 59.7), 41.8% (95% UI 35.0 to 48.6) and 37.0% (95% UI 30.9 to 43.9), respectively) and age-standardised incidence rates (48.2% (95% UI 41.5 to 55.1), 43.6% (95% UI 36.6 to 50.7) and 36.8% (95% UI 30.4 to 44.3), respectively) between 1990 and 2017.
Conclusions
RA is a major global public health challenge. The age-standardised prevalence and incidence rates are increasing, especially in countries such as Canada, Paraguay and Guatemala. Early identification and treatment of RA is vital especially among females, in order to reduce the ongoing burden of this condition. The quality of health data needs to be improved for better monitoring of disease burden.
Although therapeutic diets are critical to diabetes management, their acceptability to patients is largely unstudied.
To quantify adherence and acceptability for two types of diets for diabetes.
Controlled trial conducted between 2004 and 2006.
Individuals with type 2 diabetes (n=99) at a community-based research facility. Participants were randomly assigned to a diet following 2003 American Diabetes Association guidelines or a low-fat, vegan diet for 74 weeks.
Attrition, adherence, dietary behavior, diet acceptability, and cravings.
For nutrient intake and questionnaire scores, t tests determined between-group differences. For diet-acceptability measures, the related samples Wilcoxon sum rank test assessed within-group changes; the independent samples Mann-Whitney U test compared the diet groups. Changes in reported symptoms among the groups was compared using chi(2) for independent samples.
All participants completed the initial 22 weeks; 90% (45/50) of American Diabetes Association guidelines diet group and 86% (42/49) of the vegan diet group participants completed 74 weeks. Fat and cholesterol intake fell more and carbohydrate and fiber intake increased more in the vegan group. At 22 weeks, group-specific diet adherence criteria were met by 44% (22/50) of members of the American Diabetes Association diet group and 67% (33/49) of vegan-group participants (P=0.019); the American Diabetes Association guidelines diet group reported a greater increase in dietary restraint; this difference was not significant at 74 weeks. Both groups reported reduced hunger and reduced disinhibition. Questionnaire responses rated both diets as satisfactory, with no significant differences between groups, except for ease of preparation, for which the 22-week ratings marginally favored the American Diabetes Association guideline group. Cravings for fatty foods diminished more in the vegan group at 22 weeks, with no significant difference at 74 weeks.
Despite its greater influence on macronutrient intake, a low-fat, vegan diet has an acceptability similar to that of a more conventional diabetes diet. Acceptability appears to be no barrier to its use in medical nutrition therapy.
Fasting is an effective treatment for rheumatoid arthritis, but most patients relapse on reintroduction of food. The effect of fasting followed by one year of a vegetarian diet was assessed in a randomised, single-blind controlled trial. 27 patients were allocated to a four-week stay at a health farm. After an initial 7-10 day subtotal fast, they were put on an individually adjusted gluten-free vegan diet for 3.5 months. The food was then gradually changed to a lactovegetarian diet for the remainder of the study. A control group of 26 patients stayed for four weeks at a convalescent home, but ate an ordinary diet throughout the whole study period. After four weeks at the health farm the diet group showed a significant improvement in number of tender joints, Ritchie's articular index, number of swollen joints, pain score, duration of morning stiffness, grip strength, erythrocyte sedimentation rate, C-reactive protein, white blood cell count, and a health assessment questionnaire score. In the control group, only pain score improved score. In the control group, only pain score improved significantly. The benefits in the diet group were still present after one year, and evaluation of the whole course showed significant advantages for the diet group in all measured indices. This dietary regimen seems to be a useful supplement to conventional medical treatment of rheumatoid arthritis.
This report describes the construction of a questionnaire to measure three dimensions of human eating behavior. The first step was a collation of items from two existing questionnaires that measure the related concepts of 'restrained eating' and 'latent obesity', to which were added items newly written to elucidate these concepts. This version was administered to several populations selected to include persons who exhibited the spectrum from extreme dietary restraint to extreme lack of restraint. The resulting responses were factor analyzed and the resulting factor structure was used to revise the questionnaire. This process was then repeated: administration of the revised questionnaire to groups representing extremes of dietary restraint, factor analysis of the results and questionnaire revision. Three stable factors emerged: (1) 'cognitive restraint of eating', (2) 'disinhibition' and (3) 'hunger'. The new 51-item questionnaire measuring these factors is presented.
A method for estimating the cholesterol content of the serum low-density lipoprotein fraction (Sf- 0.20)is presented. The method involves measure- ments of fasting plasma total cholesterol, tri- glyceride, and high-density lipoprotein cholesterol concentrations, none of which requires the use of the preparative ultracentrifuge. Cornparison of this suggested procedure with the more direct procedure, in which the ultracentrifuge is used, yielded correlation coefficients of .94 to .99, de- pending on the patient population compared. Additional Keyph rases hyperlipoproteinemia classifi- cation #{149} determination of plasma total cholesterol, tri- glyceride, high-density lipoprotein cholesterol #{149} beta lipo proteins
Young adults frequently experiment with vegetarian and weight-loss diets. Comparisons of their experiences on these two different diets may help in the development of approaches to improve long-term adherence to weight-loss regimens. In the current study vegetarian and weight-loss diets were compared on how long and how strictly they were followed, and reasons why they were initiated and discontinued.
From 428 college students surveyed, four groups were delineated: 1) 59 participants had been following a vegetarian diet but not a weight-loss diet (Vegetarian), 2) 117 participants had tried a weight-loss diet but not a vegetarian diet (Weight Loss), 3) 133 participants had followed both a vegetarian and a weight-loss diet (Both), and 4) 119 participants had not tried either diet (Neither).
Differences were examined by comparing the Vegetarian and Weight-Loss groups as well as by comparing the two diets within the Both group. Duration of the vegetarian diet was much greater than the weight-loss diet; most participants in the Vegetarian group (62%) remained on their diet for more than 1 year, whereas the majority of the Weight-Loss participants (61%) followed their diet for 1 to 3 months. Similar results were found when comparing the two diets within the Both group. How strictly the two diets were followed, however, did not differ. Analyses revealed that reasons for discontinuing a diet varied; participants were more likely to cite boredom as a reason for discontinuing a weight-loss diet than a vegetarian diet (53% vs. 5% between groups and 30% vs. 10% within the Both group).
The longer duration of the vegetarian diet relative to the weight-loss diet warrants further investigation. Results could possibly be applied to behavioral weight-loss treatment to improve long-term maintenance.
Whether food intake can modify the course of rheumatoid arthritis (RA) is an issue of continued scientific and public interest. However, data from controlled clinical trials are sparse. We thus decided to study the clinical effects of a vegan diet free of gluten in RA and to quantify the levels of antibodies to key food antigens not present in the vegan diet.
Sixty-six patients with active RA were randomized to either a vegan diet free of gluten (38 patients) or a well-balanced non-vegan diet (28 patients) for 1 yr. All patients were instructed and followed-up in the same manner. They were analysed at baseline and after 3, 6 and 12 months, according to the response criteria of the American College of Rheumatology (ACR). Furthermore, levels of antibodies against gliadin and beta-lactoglobulin were assessed and radiographs of the hands and feet were performed.
Twenty-two patients in the vegan group and 25 patients in the non-vegan diet group completed 9 months or more on the diet regimens. Of these diet completers, 40.5% (nine patients) in the vegan group fulfilled the ACR20 improvement criteria compared with 4% (one patient) in the non-vegan group. Corresponding figures for the intention to treat populations were 34.3 and 3.8%, respectively. The immunoglobulin G (IgG) antibody levels against gliadin and beta-lactoglobulin decreased in the responder subgroup in the vegan diet-treated patients, but not in the other analysed groups. No retardation of radiological destruction was apparent in any of the groups.
The data provide evidence that dietary modification may be of clinical benefit for certain RA patients, and that this benefit may be related to a reduction in immunoreactivity to food antigens eliminated by the change in diet.
Pain intensity is frequently measured on an 11-point pain intensity numerical rating scale (PI-NRS), where 0=no pain and 10=worst possible pain. However, it is difficult to interpret the clinical importance of changes from baseline on this scale (such as a 1- or 2-point change). To date, there are no data driven estimates for clinically important differences in pain intensity scales used for chronic pain studies. We have estimated a clinically important difference on this scale by relating it to global assessments of change in multiple studies of chronic pain. Data on 2724 subjects from 10 recently completed placebo-controlled clinical trials of pregabalin in diabetic neuropathy, postherpetic neuralgia, chronic low back pain, fibromyalgia, and osteoarthritis were used. The studies had similar designs and measurement instruments, including the PI-NRS, collected in a daily diary, and the standard seven-point patient global impression of change (PGIC), collected at the endpoint. The changes in the PI-NRS from baseline to the endpoint were compared to the PGIC for each subject. Categories of "much improved" and "very much improved" were used as determinants of a clinically important difference and the relationship to the PI-NRS was explored using graphs, box plots, and sensitivity/specificity analyses. A consistent relationship between the change in PI-NRS and the PGIC was demonstrated regardless of study, disease type, age, sex, study result, or treatment group. On average, a reduction of approximately two points or a reduction of approximately 30% in the PI-NRS represented a clinically important difference. The relationship between percent change and the PGIC was also consistent regardless of baseline pain, while higher baseline scores required larger raw changes to represent a clinically important difference. The application of these results to future studies may provide a standard definition of clinically important improvement in clinical trials of chronic pain therapies. Use of a standard outcome across chronic pain studies would greatly enhance the comparability, validity, and clinical applicability of these studies.
To demonstrate the effects of a very low-fat, vegan diet on patients with rheumatoid arthritis (RA).
Single-blind dietary intervention study. SUBJECTS AND STUDY INTERVENTIONS: This study evaluated the influence of a 4-week, very low-fat (approximately 10%), vegan diet on 24 free-living subjects with RA, average age, 56 +/- 11 years old. Outcome measurements: Prestudy and poststudy assessment of RA symptomatology was performed by a rheumatologist blind to the study design. Biochemical measures and 4-day diet data were also collected. Subjects met weekly for diet instruction, compliance monitoring, and progress assessments.
There were significant (p < 0.001) decreases in fat (69%), protein (24%), and energy (22%), and a significant increase in carbohydrate (55%) intake. All measures of RA symptomatology decreased significantly (p < 0.05), except for duration of morning stiffness (p > 0.05). Weight also decreased significantly (p < 0.001). At 4 weeks, C-reactive protein decreased 16% (ns, p > 0.05), RA factor decreased 10% (ns, p > 0.05), while erythrocyte sedimentation rate was unchanged (p > 0.05).
This study showed that patients with moderate-to-severe RA, who switch to a very low-fat, vegan diet can experience significant reductions in RA symptoms.