Major claims have been made regarding curing or significantly alleviating MS through specific diets. Some people are very passionate supporters of a specific diet, but none of these diets have been shown to work for everyone who tries them.
It can be hard to compare different special diets for MS, as the people in the trials and the components of the diets in different studies can vary a great deal. People who are taking part in a study can't help knowing what they are eating, which makes it possible for personal biases to creep in when they report how they feel to the researchers. Also, several studies look at wellness programmes where diet is only one of the factors that is changed. Exercise, mindfulness classes, participation in group activities and dietary supplements might also be included, so it is difficult to say what change made the most difference.
Here are the main features of the diets where such claims have been made.
The Swank diet
In 1948, Dr Roy Swank began treating people with MS with a diet very low in all kinds of fats, because of the possible association between dietary fat and MS. This diet suggests cutting out all processed foods, and sticking to low-fat dairy products, whole-grain starches and no red meat. A cod liver oil and multivitamin supplement is also recommended.
Over many years, those people who followed the diet strictly and were experiencing mild symptoms when they started the diet had slower disability progression than those who had not stuck strictly to the diet. However, there was no comparison group in this study, so the results are of limited significance.
The benefits found by some people with MS might be due to the low fat diet or be because they were less severely affected by MS than the people who dropped out of the study. The results could also have occurred due to chance alone.
The Palaeolithic Diet (and Wahls Protocol)
The palaeolithic or Palaeo Diet is based on the hypotheisis that the modern diet that emerged after the development of agriculture is not suitable for our bodies. It is unlike the other diets in that it is a high-protein diet and relatively high in fats. All processed foods and domesticated meats should be avoided in a Palaeo diet, and natural high fibre foods eaten regularly. Cereals, dairy and eggs are also avoided.
This diet is a component of the diet plan promoted by Dr Terry Wahls. A small study found a significant improvement in fatigue scores with this diet, but the study also included other lifestyle changes and had nothing to compare it with. A more recent study with a comparison group showed that the Palaeo diet resulted in improvements in cardiovascular health. This group also lost more weight than the other group, and the benefit could have come from that alone.
The low intake of cereals and dairy foods could produce deficiencies in folic acid, thiamine, vitamin B6, vitamin D and calcium, and also in insufficient calorie intake.
The Best Bet diet
The Best Bet diet is a strict exclusion diet developed by Ashton Embry. It is based on the hypothesis that MS is caused by food proteins escaping from a leaky gut, causing the immune system to malfunction.
In this diet, all foods that might mimic the protein structure of myelin are removed from the diet, and you are encouraged to take a food intolerance test and also cut out anything that you personally react to. It is a gluten-free and dairy-free diet, and encourages cutting out yeast, eggs, red meat and soya as well. A large number of supplements are recommended, including Vitamin D, fatty acids, calcium and magnesium.
Anecdotal reports from people with MS suggest that the Best Bet diet works for some people, but does not work for others. A very small trial found that this diet resulted in less disability and cognitive decline than a comparison healthy diet. It can be hard to achieve a balanced diet with this approach and the large number of supplements may be expensive.
The Mediterranean diet
This diet is very well studied, and is similar to the Palaeo diet but perhaps more practical to follow. There is good evidence that the Mediterranean diet benefits heart and vascular health, and may prevent type 2 diabetes and some cancers.
This is a basically healthy diet, focussing on whole grain bread, pasta and couscous, lots of fruit and vegetables, along with olive oil, low-fat dairy foods and plenty of water. Red meat and sweet treats are allowed, but rarely. Fish and poultry are allowed several times a week, but having a few vegetarian days or meals is also encouraged. Red wine in moderation is encouraged.
The components of the Mediterranean diet have been studied in relation to MS, but results are not conclusive. It seems that the whole diet is likely to be beneficial, rather than just one element, such as olive oil. Switching to this diet can improve some MS symptoms and also help manage your weight.
The Overcoming MS diet
This specific dietary approach was developed by Professor George Jelinek based on his own experience with MS. It is a plant-based wholefood diet; basically vegan with the addition of seafood. Jelinek recommends cutting out all saturated fat, processed foods, eggs, dairy and meats.
Professor Jelinek also advocates a healthy lifestyle including meditation and exercise, and omega-3 fatty acid supplements with 20-40mls of flaxseed oil or fish oil daily. Cocoa and wine are allowed. The overcoming MS diet could be low in calcium and iron, therefore care is needed to ensure that appropriate alternative foods that provide these essential nutrients.
The McDougall diet
The McDougall diet is based on the premise that the rich Western diet is the cause of chronic diseases. It is a low-fat, high-carbohydrate, vegan diet. The diet is based around starchy, whole grain foods and lots of fruit and vegetables. No meat, dairy or extra oils are allowed, and only small amounts of sugar and salt.
There is no evidence that this diet is effective in alleviating MS or other immune diseases. In the short term, this diet may cause weight loss and lowered blood pressure and cholesterol levels. However, the long term effects have not been studied. As with any vegan diet, deficiencies in iron, vitamin B12, vitamin D, calcium and omega-3 fatty acids are possible.
A gluten-free diet
A gluten-free diet avoids all food products that derive from cereals such as wheat, rye and barley. Gluten is a major protein found in these cereals, and is known to be a source of sensitiivity for people wirth coeliac disease.
There is no evidence for a connection between coeliac disease and MS, or that a gluten-free diet can help people with MS. However, there is no reason why a person might not have both conditions. So long as gluten-free alternatives are found for the energy-rich foods in your diet, a gluten-free diet should not cause any nutritional deficiencies.
A calorie-restriction diet
Scientific findings from the study of ageing suggest that a general calorie reduction can reduce markers of inflammation and oxidative cell damage. This may increase health and longevity. If it is simply cutting calories that is important in MS, then this may explain some of the positive findings of the other diets. In practice, this would likely mean cutting out fatty, sugary and processed foods, and may not look all that different to the other suggested diets. There is evidence that calorific restriction is effective in animal versions of MS, and studies on MS in people are in progress.
An intermittent fasting diet is a version of calorie restriction. This approach to diet is less concerned about what you eat and more about when you eat it. The theory behind this approach is that the our lifestyle promotes eating constantly throughout the day. By having some extended periods in the week with limited calorie intake, our bodies are able to focus on repairing cell damage.
Calorie restriction diets are associated with lower levels of inflammation and oxidative stress, maintaining a healthy weight, and with cardiovascular health. Some people choose two days in the week where they restrict their calories to around one quarter of their normal intake. Some people make sure they don't eat after 6pm, so as to have a long fasting period overnight. Making healthy choices on the other days, and drinking plenty of fluids is also recommended.
What to consider for any MS diet
Any diet can be difficult to follow, and, before embarking on one, it is worth considering these points:
• have you been given balanced or evidence-based information about the diet, or does it only seem to be promoted by enthusiasts?
• will the diet be worse than the symptoms that it might alleviate - for example, will it stop you eating all the foods you enjoy, or make going out for meals or eating with family or friends difficult?
• does it make realistic claims for improvements in MS?
• will your diet still be balanced?
• how affordable is it?
• will cooking or preparing it be a problem?
• is it recommended by your GP or dietitian?