Multiple sclerosis develops when the body's immune system mistakenly attacks its own central nervous system. There is no cure, but there are various treatments, and certain dietary choices may help some people.
When a person develops multiple sclerosis (MS), the myelin that coats nerve fibers becomes damaged. As a result, the nerves start to lose the ability to transmit electrical signals.
This means that the brain becomes less able to tell the muscles what to do, often leading to symptoms such as pain, weakness, and tingling. A person may also notice mood changes, fatigue, trembling, and other complications.
In remitting-relapsing MS, the symptoms come and go. A person experiences symptoms that flare, or relapse, and times of remission. In other types of MS, which are progressive, the symptoms gradually worsen.
Often, a person receives the diagnosis of MS between the ages of 20 and 40, but it can develop at any time.
Dietary factors may have some impact. Understanding the role of the diet in MS and making certain changes may result in fewer relapses, a lower risk of health complications, and a better quality of life.
MS appears to be an autoimmune disease, in which the immune system mistakenly attacks the nervous system.
The relationship between the diet and MS may involve:
- the role of gut bacteria in immune disorders
- vitamin deficiencies
- the fact that some nutrients can support and protect the nervous system
- the benefits of healthful eating for overall wellbeing
Certain foods may benefit people with MS by affecting how the immune system, the nerves, and other parts of the body work.
Probiotics and prebiotics
Changes in gut health may contribute to immune disorders, and research indicates that the health of the gut appears to play a role in many kinds of diseases.
The intestinal flora, or gut flora, is a highly complex system of microorganisms that live in the intestines. In humans, these microorganisms are largely bacteria.
The bacteria are responsible for breaking down food and nutrients, and they play a key role in digestion and the health of the immune system. Healthy gut flora thrive in the intestines when there is ample fiber in the diet.
A lack of healthy gut flora may contribute to a range of immune disorders, including MS. Anyone with the condition should have a diet that supports a healthy immune system, and one that promotes beneficial gut flora may help.
Probiotics are foods that can boost levels of beneficial bacteria in the gut, helping to strengthen the immune system.
The authors of a study in Nature Communications suggest that adjusting the gut flora, by using probiotics, for example, may be helpful for people with MS.
Probiotic bacteria are available in supplements and a range of fermented foods. The following all contain healthful levels of Lactobacillus, which is one type of beneficial bacteria:
- kombucha, or fermented tea
After filling the gut with good bacteria, it is important to feed them. Foods that nourish probiotic bacteria are called prebiotics, and they contain fiber.
Foods that contain healthful levels of prebiotic fiber include:
Fiber occurs in plant-based foods, such as:
- nuts and seeds
- legumes, such as lentils
- whole grains
- brown rice
It helps promote health in the following ways:
- nourishing the gut bacteria
- encouraging regular bowel movements
- keeping blood pressure and the heart healthy by helping manage cholesterol
- reducing the risk of weight gain by leaving a person feeling full for longer
Vitamin D is important for everyone, but it may be especially beneficial for people with MS. According to the National Institute of Neurological Disorders and Stroke, people with high levels of vitamin D appear to have a lower chance of developing MS.
Vitamin D is also important for bone health. People with MS may be more likely to experience low bone density and osteoporosis, especially if they are not able to move easily. An adequate intake of vitamin D may help prevent this.
Most of the body's vitamin D comes from exposure to sunlight, but a person also takes it in by consuming:
- oily fish
- fortified dairy products
- some fortified cereals, yogurt, and orange juice
- beef liver
- egg yolks
A review published in 2017 notes that, while evidence of a link between low vitamin D levels and MS is accumulating, confirming the link will require more research.
Biotin is a form of vitamin B, and some people call it vitamin H.
It occurs in many foods, but good sources include:
- beef liver
- sunflower seeds
- whole-wheat bread
Researchers have been looking into whether biotin might benefit people with MS. Findings from small studies indicate that a high dosage of biotin — between 100 and 600 milligrams per day — could help people with progressive MS, in which symptoms gradually become more severe.
Confirming and specifying the benefits of biotin supplementation will require more research, but following a healthful diet can often ensure that a person is consuming enough of this vitamin.
Polyunsaturated fatty acids
Investigations into whether a diet rich in polyunsaturated fatty acids (PUFAs) directly helps relieve MS symptoms have yielded mixed results. However, there is evidence that these acids help support a healthy body and control inflammation.
A study published in 2017 concluded that a low intake of PUFAs may increase the risk of MS. The study looked at data from more than 170,000 women.
PUFAs appear to boost bodily functions ranging from cardiac health to the ability to think. Examples of foods that contain PUFAs include fatty fish, such as salmon and mackerel, and some plant-based oils.
Many vegetable-based foods contain substances called polyphenols, which have antioxidant and anti-inflammatory effects on the body's cells. These effects may help prevent cell damage, making polyphenols potentially useful for people with MS.
Sources of polyphenols include:
Antioxidants can also help prevent oxidative stress, which researchers have linked to a wide range of health problems.
Some antioxidants — specifically resveratrol, which occurs in grapes — appear to help protect the nervous system.
A review published in 2016 concluded that obesity during childhood and adolescence might increase the risk of developing MS. The researchers also noted that obesity could affect the progression of the disease.
In addition, a person with MS who loses mobility or who finds movement more challenging may have a higher risk of putting on extra weight.
Managing the diet to prevent weight gain may also help prevent MS symptoms from worsening. These types of dietary changes may boost a person's sense of well-being and reduce the risk of additional health conditions, such as cardiovascular disease.
Some foods may be harmful to people with MS.
Saturated fats and processed foods
Processed foods can have a negative impact on a person's health, especially if they contain high levels of:
- saturated fats, trans fats, and hydrogenated oils
- added sodium, or salt
- added sugar
An article published in ASN Neuro in 2015 noted that people with MS who have a moderate or high sodium intake are more likely to experience a relapse of symptoms or develop a new lesion.
The authors also suggested avoiding:
- sugar-sweetened drinks
- excessive quantities of red meat
- fried foods
- low-fiber foods
These, they point out, can trigger inflammation in the body. A healthful diet that includes fresh fruits and vegetables can reduce inflammation, due to its antioxidant effects.
Anyone on a specific diet needs to be sure that they are consuming all the required daily nutrients. A person who eliminates a particular food or food group should ensure that they replace any nutrients lost.
Research has not confirmed a link between gluten and MS, but people with MS appear to have a higher likelihood of developing celiac disease, which prevents the body from tolerating gluten. Both diseases seem to stem from a problem with the immune system.
Foods that contain gluten include:
- wheat products, such as breads, baked goods, and many premade soups and salad dressings
- barley products, such as malt, soups, beer, and brewer's yeast
- rye, which is often present in bread, rye beer, and cereals
People who follow a gluten-free diet may miss out on important nutrients, including fiber, which is present in whole grains. They should boost their fiber intake by eating plenty of fresh vegetables, fruits, nuts, seeds, and pulses.
Anyone considering a gluten-free diet should speak to their doctor first.
Many people on the Paleo, or Paleolithic, diet believe that the human body has not evolved to eat the highly processed foods that we now consume.
The diet involves switching to foods that were likely eaten by hunter-gatherers. The first step is to choose natural foods over processed foods, with an emphasis on meat and plant-based foods, but not grains.
In a 2019 review, researchers, including an advocate of the Paleo diet, compared a modified version of it with another diet — the Swank diet — to test, among other factors, the effects on MS-related fatigue. There is some evidence that the diets may reduce this fatigue, but confirming this will require more research.
Doctors developed the Swank diet as an MS treatment in the 1950s.
It reduces saturated fat intake to, at most, 15 grams per day and recommends limiting unsaturated fat intake to 20–50 grams per day.
People on this diet:
- cannot eat processed foods or dairy fats
- cannot eat red meat, during the first year
- can eat as much white fish and shellfish as they like
- should eat at least 2 cups each of fruits and vegetables every day
- should eat whole-grain pasta
- should take cod liver oil and multivitamins every day
While some consider the diet to be dated, others report that it helps.
How do the diets compare?
In 2015, the National MS Society reviewed a number of diets and their impact on the disease. The authors conclude that there is not enough evidence to recommend one diet over another and acknowledge that most of the diets restrict or leave out the same types of food.
A person should avoid foods that:
- are highly processed
- are high in saturated fat
- have high glycemic index ratings, suggesting that they contain high levels of sugar or are significantly processed
In general, the diets tend to involve eating:
- less fatty red meat
- more fruits and vegetables
A healthful diet for a person with MS is one that supports the immune system.
Additional changes that may help include:
- increasing sunlight exposure to boost vitamin D levels
- exercising to help maintain strength and flexibility and support overall health and well-being
- quitting smoking and avoiding secondhand smoke
Anyone considering making major changes to their diet or lifestyle should talk to a doctor first.
MS can affect any part of the body. The most common symptoms include:
Changes in thinking: These can involve attention-related difficulties, memory loss, forgetting certain words, and problems with abstraction.
Vision problems: A person may experience blurred or double vision, red-green color distortion, or partial or complete vision loss in one eye.
Muscle problems: These can include weakness, numbness, and difficulty with coordination and balance. In severe cases, MS can result in partial or complete paralysis.
Changes in sensation: Tingling, numbness, and pain may occur.
People with MS can also experience bladder problems, falls, depression, or a range of other secondary symptoms.
MS affects the nervous system and can lead to a wide variety of primary and secondary symptoms and health issues. It is a lifelong condition that may come and go or progress steadily, depending on the type.
Some people only ever experience mild tingling, while others become unable to move or talk. Most people with MS remain mobile, however, and the majority of people with MS have the same life expectancies as people without the condition.
Healthful dietary choices can benefit people with MS, and certain changes may alter the progress of the condition or prevent specific symptoms.
In general, a healthful diet can boost a person's overall well-being and quality of life, while preventing complications such as cardiovascular disease.