What to Know About Popular MS Diets

The Effects of Diet on MS

Multiple Sclerosis is a chronic immune-mediated demyelinating disorder that affects the central nervous system (CNS). In MS, the immune system functions abnormally and targets cells and tissues within the CNS, causing inflammation and damage to myelin, nerve fibers and the cells that make myelin.  

Several genetic and environmental factors that influence the risk for developing MS have now been identified, including low Vitamin D, exposure to the Epstein Barr Virus, smoking, childhood obesity, and others. (Perhaps the most significant dietary factor that has been linked with the occurrence of MS and its disease course is low vitamin D.) 

The Impact of Diet on Autoimmunity 

There is increasing interest in the possible role of diet in autoimmunity and in the role of dietary interventions in diseases such as MS. Ongoing research is demonstrating a link between the gut microbiota (bacteria in our gut) and MS. Diet plays a significant role in shaping our gut microbiota and is also implicated in several other chronic diseases (type 2 diabetes, obesity, hypertension). Although there is a lot of ongoing research and many diets have been suggested as helpful to people with MS, there is no specific diet or dietary supplement that has been demonstrated in well-designed clinical trials to change the course of MS.  

That said, what is known about diet and MS? 

Possible mechanisms by which diet may have an effect on MS

1. Direct effects on the immune system: Recent immunological research has shown that metabolism plays a significant role in the function of several types of immune cells. Additionally, several immune cells have receptors (surface structures that allow cells to connect and communicate with other cells) for distinct types of dietary metabolites (vitamin D, fatty acids). Thus, intake of certain types of fats has been linked to greater inflammation while intake of polyunsaturated fatty acids (PUFAs) reduces inflammation.
2. Indirect effects through modulation of the gut flora: The gut bacteria metabolize certain components of the diet into short chain fatty acids that, besides improving the health of the colon, can also act on immune cells and increase the regulatory function of T cells (a type of white blood cell, or lymphocyte). Additionally diet can lead to alterations in the gut bacterial composition that can shift the immune system towards a pro- or anti-inflammatory state.
3. Effects on components of the central nervous system: As mentioned above, since altered metabolism may play a role in the adaptation of the nervous system to damage, various experimental foods and diets are being studied for their effects on various cellular components of the central nervous system such as the neurons and other glial cells. Diets could have a beneficial role by providing factors that help protect these cell populations.

There are several diets that have been suggested to be useful in MS. While the research does not currently identify any single diet as helpful to the MS disease course, many people are interested in learning about them, and the research in MS that is being done to evaluate them. The Paleolithic, Wahls protocol, Mediterranean, Swank, Intermittent Fasting and Gluten free diets are reviewed below, including recent research findings in MS, and any possible nutritional deficiencies that may arise from following any of these diets.  

Wahls Protocol

The Wahls protocol was developed by Dr. Terry Wahls following her own diagnosis of MS. She found, through her own research, which following a specific diet seemed to improve her mobility. Dr. Wahls believes that dietary support of the mitochondria – the energy producer within our cells – can be beneficial in MS. 

Guidelines for the Wahls Protocol diet

The Wahls protocol diet is similar to the Paleo diet.  

In a Paleo diet, the recommendation is to eat what would have been consumed by our ancestors – before grain farming and processed foods. The Paleo diet emphasizes the intake of game (non-domesticated) meats and plant-based foods, including fruits, roots, legumes, and nuts – but avoiding cereal grains. The Paleo diet is also high in fiber (45-100 g/day) that is derived from plant sources that are not cereal based.  

The modified Paleo Diet in the Wahls protocol emphasizes specific amounts of foods such as grass fed meats, wild caught fish and plenty of vegetables, particularly dark green leafy vegetables. This diet also includes are brightly colored fruits. Foods to be avoided are processed foods, soy, dairy, eggs, and beans. More specific information about the Wahls Protocol can be found here.

Evidence for a role in MS 

Dr. Wahls has pursued clinical trials of her diet, and in 2009 she and her team published findings of a small, uncontrolled, single-arm study that looked at the effect of a multimodal intervention (including exercise, electrical stimulation of muscles, and a modified Paleo diet) on people with secondary progressive MS. This study found significant improvement in fatigue scores over a period of 12 months. In 2021 Dr. Wahls and her team published a second study that compared the Swank diet and the modified paleolithic diet in relapsing-remitting MS. Results showed that fatigue was reduced, and physical quality of life scores improved with both diets. Mental MS quality of life scores improved in the modified paleolithic group.

Dr. Wahls team recently received a $2.5 million gift from the Chapman-Shreve Foundation to compare the effects of the modified Paleolithic elimination diet, the ketogenic diet, and a control diet (a person’s usual diet), on quality of life and fatigue. The two-year Efficacy of Diet on Quality of Life in Multiple Sclerosis (EDQ-MS) study will enroll 156 people who have MS. This will be one of the largest and longest MS diet studies ever done.  

Possible deficiencies that may result from the diet 

The Paleo diet can result in deficiencies in folic acid, thiamine, and vitamin B6 (due to reduced intake of cereals), calcium and vitamin D (due to lack of dairy intake). 

Mediterranean Diet (MD)

1. The MD is one of the most extensively studied diets in the setting of cardiovascular health. It has several similarities to the Paleolithic diet but is easier for many people to follow. The MD has many components that are thought to be beneficial, however most research suggests the MD has far greater benefits than its individual components.

• Guidelines for MD
  There are various definitions of the MD, however they generally share the following components: high intake of whole grains, vegetables, fruits, legumes, olive oil and fish; a low intake of saturated fats (butter and other animal fats), red meat, poultry, dairy products; and a regular but moderate intake of ethanol (mainly consisting of red wine during meals).The MD is part of the Mediterranean lifestyle.

• Evidence for a role in MS or other autoimmune disorders
  A large investigation of seventeen randomized trials of the MD, known as a meta-analysis, demonstrated a benefit of the MD on markers of inflammation.In 2022, two published studies indicated possible benefits of the MD in people with MS. In a study of 102 people with MS, those who followed the MD reported less fatigue and overall self-report of MS symptoms. In the second study of over 500 people, participants completed an MD questionnaire and other MS related assessments. Results showed that those who followed the MD more closely had higher objective scores on each component of the MSFC (MS Functional Composite) – upper extremity function, cognitive function, and walking speed. In addition, using self-report outcome scales, those who followed the diet more closely had lower depression, fatigue, and anxiety scores.
  
  There is evidence for a beneficial effect of the MD in type 2 diabetes, cardiovascular disease prevention and perhaps even in cancer prevention.

• Nutritional deficiencies that may result from following this diet
  No specific nutritional deficiencies would be expected from following the MD. 

Gluten Free Diet (GFD)

A GFD is a diet completely devoid of wheat, barley, rye and triticales (a cross between wheat and rye). Gluten is a protein composed of gliadin and glutenin, which are found conjoined with starch in wheat, rye, and barley. It is a major component of the proteins found in wheat. 

Gluten sensitivity is a feature of celiac disease and GFD is a common treatment for this disorder. Besides celiac disease, gluten sensitivity has also been noted in a condition called non-celiac gluten sensitivity (NCGS), which can also lead to gastrointestinal symptoms. 

• Guidelines for a GFD
  It is important to remember that “wheat-free” is different from “gluten free.” For a GFD, it is necessary to avoid all food containing any derivatives of wheat, barley or triticales (a cross between wheat and rye). Additionally, it is also important to look for cross-contamination that can occur if the food is prepared in an area where these products are utilized. It is also important to find substitutes for the eliminated food to reduce the risk of nutritional deficiencies.  
• Evidence for a role in MS
  There is no evidence for a role of GFD in patients with MS. Multiple studies suggest that people with MS have the same prevalence of anti-gliadin and anti-TTG antibodies (antibodies elevated in Celiac disease) as healthy controls.
  It has also been evaluated in other autoimmune conditions such as rheumatoid arthritis with no definite role for GFD noted in these disorders.
• Nutritional Deficiencies that may result from this diet
  There is evidence that the grains used in a GFD may be lower in iron, fiber, B-vitamins, Vitamin D, calcium, phosphorus, and zinc. In addition, there may be more fat, carbohydrates, and a higher glycemic index with a GFD.

Swank Diet

The Swank diet was described by Dr. Roy Swank and was used by him to treat patients with MS for several years. The diet is essentially a low–fat diet that focuses on reducing both saturated and unsaturated fats.

• Guidelines for the Swank Diet 

• • Saturated fat intake should not exceed 15 grams/day, while unsaturated fat /oils intake should be kept below 20-50 grams/day. No processed foods containing saturated fats should be consumed. Similarly dairy products must contain less than 1% fat. 
  • Whole grain cereals and pastas are recommended.  
  • Two cups each of fruits and vegetables per day 
  • No red meat is allowed for the first year, after which 3 oz. of red meat are allowed weekly. White fish and shellfish are permissible in any amount. Skinned trimmed poultry meat is permissible. 
  • No red meat is allowed for the first year, after which 3 oz of red meat are allowed weekly.  

• • Permissible foods include white fish and shellfish, skinned, trimmed poultry meat in any amount 
  • A cod liver oil and multivitamin supplement is recommended. 
• Evidence for a role in MS
  In 1970, Dr. Swank reported the effects of his diet over a period of 20 years on patients with MS. In this observational report, he suggested that the diet reduced relapses, accumulation of disability, and mortality. It is important to note that the study did not have a control arm to compare the subjects on this diet with those following another diet. Also, a standardized scoring system such as the EDSS was not available at that time, making comparison with other groups of MS patients challenging. In a 2021 study by Terry Wahls, MD, and her team, both the modified Paleo diet and the Swank diet were found to reduce self-reported fatigue.  
• Nutritional deficiencies that may develop due to this diet 
  Though no definite deficiencies would be expected to develop from this diet, however, a recent study showed that those following this diet were consuming less than the recommended levels of vitamin A, C, E, and folate.

Intermittent Fasting

Intermittent fasting is all about when you eat, where other diets are about what you eat. Intermittent fasting can mean eating during certain hours of each day, complete fasting on scheduled days or reducing calories every day or on alternate days. In any of these regimens, most people will lose weight. But researchers are also seeing benefits in Type 2 diabetes and elevated lipids.

• Guidelines for intermittent fasting
  There are numerous regimens for intermittent fasting – and none should be undertaken without first speaking with your healthcare provider. A daily approach restricts eating to a 6-8 hour period each day and fasting the remaining 16-18 hours each day. Another regimen involves eating regularly 5 days each week and limiting yourself to one meal of 500-600 calories on the other 2 days. And a restricted calorie diet involves a person eating fewer calories than they need for the day.
  There are people with certain conditions who should not participate in calorie restriction or intermittent fasting – for example, those with diabetes, hypertension, eating disorders, women who are pregnant or breastfeeding, and others. A discussion with your healthcare provider is recommended if you are interested in this type of diet. 
• Evidence for a role in MS
  The current research evidence is limited for benefits of intermittent fasting or calorie restriction for people with MS.
  Studies in EAE (experimental autoimmune encephalomyelitis – the animal model of MS) found that intermittent fasting reduced inflammation, demyelination, and axonal damage.
  A small 2018 study of intermittent fasting, calorie restriction and a normal diet in people with MS suggested a potential role for intermittent fasting in modulating the immune effects in MS. In that same study, both the calorie restriction and intermittent fasting diets showed improvements in emotional health. In the group who fasted 2 day/week, there were changes in certain types of T cells that are associated with inflammation in MS.
  These studies were small, but suggestive of positive effects. Additional studies are needed to further understand any benefit as well as any risks of intermittent fasting for people with MS.  
• Nutritional deficiencies that may develop due to the diet
  In general, intermittent fasting does not produce nutritional deficiencies – if the foods eaten are of nutritional value. However, if fasting is prolonged or foods are of limited nutritional value, nutrient deficiencies are possible. If intermittent fasting is a diet of interest to you, we recommend a discussion with your healthcare provider to ensure your nutritional and overall health. 

Conclusions

While many different dietary strategies are being promoted for people with MS, currently there is insufficient evidence to recommend any of these strategies as having the ability to change the natural history of MS. 

Interestingly, despite the differences between these diets there are several common themes. Almost all diets advocate avoiding highly processed food, foods with high glycemic index and food that is high in saturated fat. Most diets also recommend reducing consumption of fatty red meat and increasing consumption of fruits and vegetables. 

To truly know “the best diet for MS,” we will need to wait for more systematic research to be conducted and published. While we wait, your most reasonable option is to follow a diet that incorporates these common, health-promoting themes. Should you have interest in this or any other diet strategy, consider a discussion with your healthcare provider.