The Swank diet appeared in the 1950s as a treatment for people with multiple sclerosis. Supporters claim it can reduce the frequency of flares and the severity of symptoms.
A central feature of the diet is that it limits fat — especially saturated fat — and focuses on lean fish, non-fat dairy products, fruits, vegetables, and whole grains.
Dr. Roy Swank began studying multiple sclerosis (MS) in the 1940s. His research in Canada and Norway led him to conclude that MS was less common in coastal fishing towns, where people ate more fish than in the mountains, where there was a higher intake of meat.
Working with a dietitian, Aagot Grimsgard, Dr, Swank developed a low-fat diet. He published a book on the diet in 1987.
In this article, we look at what the Swank diet consists of and the effect it might have on multiple sclerosis (MS).
What is MS? Find out here.
The Swank diet gives guidance on how much of various food types a person should eat.
The diet recommends consuming:
- no more than 15 grams (g) of saturated fat per day
- no less than 20 g of unsaturated fat per day
- no more than 50 g of total fat per day
A person can consume plant oils, such as olive oil, canola oil, soybean oil, peanut oil, and flax oil on the Swank diet because they contain mostly unsaturated fat.
Oils to avoid include:
- coconut and palm oils, as they are high in saturated fat
- butter, lard, margarine, shortening, and hydrogenated oils, as they are high saturated or trans fat
A person can eat nuts, nut butter, and seeds as snacks, but they must count them in the daily fat total.
What are healthful fats? Learn more here.
Fruits and vegetables
The Swank diet encourages a person to consume at least 2 servings each of fruits and vegetables per day.
A person can eat most fruits and vegetables on the Swank diet without restriction. However, if a fruit naturally contains fat, such as avocados and olives, the person must count this towards their daily fat total.
Meats and poultry
A person cannot consume red meat and pork during the first year of the diet. After that, they may eat 3 ounces (oz) of cooked red meat.
However, people can eat 4 oz skinless white chicken and turkey meat but should avoid dark poultry meat and processed poultry products.
Whitefish and shellfish are suitable, and there is no limit to the portion size, but people with high cholesterol levels should limit their shellfish consumption.
When eating fatty fish, such as salmon and tuna, people must include it in their daily fat total.
Dairy and eggs
The Swank diet recommends 2 servings a day of non-fat or low-fat dairy products.
There is no restriction on servings of some dairy products, such as non-fat milk, non-fat cottage cheese, and fat-free cheese.
Egg yolks contain saturated fat, so a person should eat no more than one whole egg three times a week.
The Swank diet recommends consuming 4 servings of grain products a day.
People can eat bread, low-fat cereals, rice, pasta, and certain crackers, preferably whole grain products.
People should avoid cakes and other baked goods that contain a fat source, such as butter or lard.
Caffeine and alcohol
A person should consume no more than three caffeinated beverages a day. They can also consume 1 serving per day of wine or liquor.
The diet recommends specific vitamin and mineral supplements, including:
- cod liver oil
- a multivitamin with minerals
- vitamin C
- vitamin E
Dr. Swank published several articles advocating the benefits of a low-fat diet for people with MS, and these included research based on the findings of his original studies.
In 1990, he published a 34-year follow-up study on 144 people with MS. He reported that those who ate less than 20 g of saturated fat per day had less disease progression and were less likely to die than those who ate more saturated fat.
However, the study had several weaknesses:
- there was no control group for comparison
- the study lacked strict inclusion criteria
- there was a high drop-out rate among participants
Expanding on Dr. Swank’s work, a 2016 study looked at how following another plan, the McDougall Program, for 1 year affected people with MS.
The McDougall Program is another very low-fat diet, but it also excludes meat, fish, eggs, dairy, and vegetable oils.
Those who followed the program did not see improvements in their brain scans or the number of flares they experienced, compared with the control group. However, they did report improved energy levels and positive changes in their BMI.
Interestingly, cholesterol and insulin levels were lower in the diet group after 6 months, but not when the study ended.
There are some drawbacks to the Swank diet:
- It is very restrictive, and some people may find it challenging to follow over a long period.
- One study found that people who followed the diet did not get enough vitamin C, A, E, or folate.
- People on a very low-fat diet, such as the Swank diet, may also experience drier skin and hair and have lower energy levels than other people.
Many people with MS use nutrition as a form of complementary or alternative treatment.
The National Multiple Sclerosis Society state that there is not enough evidence to recommend which specific diet is best for people with MS.
A small survey completed in 2014 found that almost 30 percent of people with MS followed a special diet as part of their treatment.
Some people advocate a version of the Paleolithic, or “paleo” diet. Terry Wahls is a doctor, author, published researcher, and a clinical professor of medicine who also has a progressive form of MS.
She has developed the Wahls protocol, which emphasizes a Paleolithic-style diet and excludes grains and gluten.
A 2017 study found that it might help as part of a complementary approach to the management of progressive MS.
Research is ongoing.
In 2009, researchers found higher levels of gluten antibodies in people with MS, compared with those without the condition. The authors suggested that a gluten-free diet might help in some cases.
Whether or not grains, gluten, or fat play a role in MS, all people are likely to benefit from a healthful diet.
A healthful diet involves:
- a low intake of sugar and salt
- a low consumption of processed foods
- a high-fiber diet, including fresh fruits, vegetables, lean proteins, and healthful fats
What is the gluten-free diet? Find out more.
Researchers have looked at certain nutrients to see if they might help with MS symptoms.
Sodium and salt
Scientists have looked at how dietary salt might impact be a factor in MS activity.
Some researchers have found evidence of:
- a link between dietary salt, increased inflammation of the nervous system, and decreased immune system function in mice
- a higher dietary salt intake and a higher chance of brain scarring and more frequent symptom flares in people with MS
However, later studies have found no links between salt and MS symptoms.
Researchers need to do further studies to confirm whether a high salt intake increases the frequency or severity of MS symptoms.
MS and fish oil
Fish oil contains omega-3 oil, which may be beneficial for nerve function and thinking. Some researchers believe that fish oil can help treat MS. CHEC
In 2016, however, another study, concluded that fish-based omega-3s might reduce the risk of an MS diagnosis over a year.
Learn more here about how fish oil might benefit a person’s health.
MS and vitamin D
People with MS are more likely to have lower levels of vitamin D than other people.
A small study indicated that vitamin D might reduce the occurrence of MS attacks. Participants who took a vitamin D supplement also had fewer nervous system scars visible on imaging.
Find out more about dietary tips for MS here.
Nutrition may play a role in treating MS, and it can help maintain overall health.
Many people now consider the Swank diet outdated. Other dietary options may help, but there is no evidence to confirm one diet over another.
Consuming plenty of fresh fruits and vegetables and avoiding processed foods and added salt and sugar are an excellent dietary choice for everyone.
As a 2019 review of web-based recommendations for MS points out, much of the advice that is available online is contradictory.
Anyone who is considering following a special diet, changing their diet, or using supplements for MS should first speak to their doctor or dietitian, as some choices may not be suitable for all and may interact with other types of treatment.
As a registered dietitian, would you recommend the Swank diet? Isn’t it a bit old now?
Since there is no evidence confirming that a specific diet helps everyone with MS, I would recommend individualizing a healthful diet plan.
I would begin with the basics that we all know are beneficial for most people. This includes consuming a variety of nutrient-dense foods, including lean proteins and low-fat dairy products, limiting saturated fat, sodium, sugar, and cholesterol, consuming whole fruits and fiber-rich vegetables every day, choosing whole grains instead of refined grains, eating more fatty fish, and opting for healthier beverages.
From there, I would help to set individualized goals that would be therapeutic to the person with MS.
Katherine Marengo LDN, RD Answers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.