Both diets resulted in patients with MS reporting significant changes on Perceived Deficits Questionnaire scores for fatigue and cognitive dysfunction after 12 weeks of intervention.
In a recent randomized, parallel-arm study, termed WAVES, the utilization of either the Wahls or Swank elimination diets for individuals with multiple sclerosis (MS) led to significant reductions for both groups in fatigue and cognitive dysfunction.1
Ultimately, at 12 weeks, the Swank diet group (n = 38) reported total Perceived Deficits Questionnaire (PDQ) scores of 25.1 (±2.00), compared with 32.4 (±2.36) at baseline, while the Wahls group (n = 39) reported total scores of 29.1 (±2.71), compared with 35.9 (±2.16) at baseline, both being a significant improvement (P ≤.05). At 24 weeks, those scores remained significant at 26.1 (±2.14) and 25.1 (±3.03), respectively (P ≤.05).
The data were presented by Tyler Titcomb, PhD, RDN, IFMCP, post-doctoral scholar, Wahls UIHC Clinical Research Lab, University of Iowa, at the 2021 Annual Meeting of the Consortium of Multiple Sclerosis Centers (CMSC), October 25-28. He explained that plans to further assess these diets are currently ongoing, with a follow-up study expected to be initiated in the coming months that will include both a control group and MRI measures.
Titcomb noted that the improvements reported by both the Wahls diet and Swank diet groups may be driven by a similar mechanistic action brought on by each diet, and he emphasized the urgent need to identify this mechanism.
“Studies are ongoing right now to try and tackle this,” Titcomb said in his presentation. “Possible mechanisms of these [diets] include modulation of the microbiome, inflammation, the immune system, or micronutrient optimization. The key thing to note is about dietary intervention studies in multiple sclerosis is that we do not know if diet impacts disease activity or not.”
Although these data were not presented at CMSC 2021, BMI was also significantly reduced for both groups—from 27.6 (±0.94) for the Swank group and 30.2 (±1.3) for the Wahls group at baseline—which Titcomb noted may also be a mechanistic driver of the improvements reported by each group. “There is plenty of evidence to show that weight loss can be beneficial [to patient-reported outcomes],” he said. Titcomb also noted that a reduction in sodium intake, likely driven by the avoidance of processed foods, may have helped influence these reductions, and that data on both of these facets was submitted to be presented at the Americas Committee for Treatment and Research in Multiple Sclerosis 2022 Forum.
The planning, prospective memory, retrospective memory, and attention portions of the PDQ scores for both groups. The Swank group reported 12-week scores of 6.81 (±0.66), 5.03 (±0.46), 6.16 (±0.58), 7.08 (±0.54), respectively, compared with 8.50 (±0.65), 6.63 (±0.57), 8.11 (±0.71), and 9.20 (±0.64) at baseline (P ≤0.05 for all). For the Wahls group, 12-week scores of 7.24 (±0.79) on planning, 6.37 (±0.57) on prospective memory, 7.63 (±0.80) on retrospective memory, and 7.87 (±0.71) on attention were reported, compared with 9.46 (±0.67), 7.33 (±0.52), 9.33 (±0.60), and 9.79 (±0.57), respectively, at baseline (P ≤0.05 for all).
“One thing to note about these figures is that if, you look in the literature, the typical person with MS has a PDQ score of about 46, so participants in both groups tended to be lower than what you would see in the general MS population,” Titcomb said. In addition to their baseline values of 32.4 and 35.9 for the Swank and Wahls groups, respectively, scores after the 12-week run-in prior to baseline were similar, at 33.1 (±2.50) and 35.1 (±2.24).
In recent years, additional literature has suggested that the Mediterranean diet may be an effective dietary intervention for patients with MS and has been recommended.2-4 With this in mind, Titcomb noted that the choice to assess these 2 diets was driven by their key differences, but also their similarities—the recommendations of fruit and vegetable consumption and avoidance of processed food, which Titcomb called their “most important” aspects.
“If you look at the whole of dietary intervention studies, they all have significant improvements because they all recommend those 2 things,” he explained in the question-and-answer portion of the session. “One of the key things [in the WAVES study] is the principle of Wahls elimination diet is based on paleo diet principles, which recommend the avoidance of grains, whereas the Swank diet recommends quite a bit of consumption of grains, so they’re drastically different in that regard.”
The Swank diet focuses on low saturated fat intake, with all participants encouraged to consume 4 servings of grains, fruits, and vegetables each day, and to limit fat consumption to less than 15 g per day. The Wahls Elimination diet, on the other hand, is a modified version of a paleolithic diet, and encourages 6-9 servings of vegetables and berries each day, with total avoidance of grains, nightshades, dairy, and eggs.
For more coverage of CMSC 2021, click here.