Intermittent fasting has become popular as a diet trend. It’s often promoted as a way of losing weight and fighting off certain diseases. But what exactly is intermittent fasting, and does it have benefits for people with MS?

As one MyMSTeam member put it, “I’ve heard of people who do fasting (going without food for days), and I’m just wondering if someone on an MS medication (or not) would be advised against it.”

It’s important to know that there is no diet that can cure or slow MS, although healthy eating can help you feel better overall and alleviate some MS symptoms. Disease-modifying treatments (DMTs) are the only treatment proven to slow the progression of MS.

Because MS shows up so differently for each person, the eating plan that energizes one person might zap another’s strength. Before you try intermittent fasting, or any new diet plan, check with your doctor to make sure it won’t interfere with your treatments. For example, if you have medication you need to take with food, it will be important to eat as needed. Skipping meals can also contribute to fatigue, brain fog, and mood swings for many people.

Read on to learn more about what fasting is, its potential risks and benefits, and how it may impact symptoms of MS.

What Is Intermittent Fasting?

Intermittent fasting involves not eating for a certain length of time on a regular schedule. Unlike most diets that are focused on the foods you eat, fasting mainly focuses on the times you eat it. It isn’t about starving yourself or being on a trendy diet for rapid weight loss. It’s about calorie restriction for brief, defined periods of time. The theory is that your body will learn to use its energy stores differently and to be satisfied with smaller portions.

Fasting has been studied for many years. It is thought that humans have evolved to survive with periods of fasting (when food was simply unavailable) since prehistoric times. In the last 50 years, fasting became popular again as more people struggled to maintain a healthy active lifestyle and snacking became a habit.

Types of Intermittent Fasting Diets

There are several types of fasting schedules. The most common forms of intermittent fasting include:

• 5:2 fasting — Limiting food or calories two days a week, and eating as you usually would five days a week
• Daily, time-restricted fasting — Fasting for a certain time period every day
• Alternate-day fasting — Fasting or limiting calories every other day
• Occasional 24-hour fasting — Avoiding all food for 24 hours once or twice a week

In daily, time-restricted fasting, people eat as they normally would, but only during a defined time period of the day. The most common plans are the 16/8 or 14/10 methods. For example, with the 16/8 method, people eat within an eight-hour period each day — for instance, between 10 a.m. and 6 p.m. The remaining 16 hours of the day is dedicated fasting time. It’s key that most of the calories are consumed before nighttime.

In alternate-day fasting, people will eat regularly on one day, and the following day they’ll either completely fast or eat one very small meal.

The 5:2 fasting schedule, also called the “twice a week” method, involves eating a maximum of 500 calories on each of two days per week. The other five days of the week, people will eat a normal, well-balanced diet, including plenty of fruit, vegetables, whole grains, and lean proteins. There must be at least one nonfasting day in between the two fasting days.

In a 24-hour fast, one fasts for a full 24 hours, typically from breakfast to breakfast or lunch to lunch. For this schedule, most people do the 24-hour fast once or twice per week.

Whenever fasting, it’s important to stay hydrated and drink plenty of water. Black coffee and unsweetened tea are also usually allowed on most fasting plans.

Benefits of Intermittent Fasting Diets

There are many claims that intermittent fasting is good for your health, can prevent disease, or can even reverse a disease you may already have. Beware of misinformation and claims that fasting offers quick health cures.

Some benefits of fasting reported by Johns Hopkins University include improved:

• Heart health (lowered blood pressure or heart rate)
• Thinking and memory
• Weight loss

It’s also been proposed that intermittent fasting can benefit people with diabetes, although anyone with diabetes should only make major dietary changes with a doctor’s supervision.

Intermittent Fasting and MyMSTeam Members

MyMSTeam members have shared both positive and negative experiences with fasting.

One member described how intermittent fasting helped with their pain relief: “Has anyone had any experience with fasting? I was unable to eat yesterday due to its hectic pace. And amazingly, my pain felt so much better as time passed. Even this morning waking up, I hurt a lot less.”

Another member wrote, “On keto and intermittent fasting. Down 26 pounds and feel better than I have ever felt since being diagnosed with MS.” A third member shared, “I am trying intermittent fasting and honestly, it helps with spasticity. I don’t move faster, but I have less pain when I do move. Start small if you try this and listen to your body and eat if you feel weak.”

However, some MyMSTeam members have had side effects from fasting. One member said, “My chronic fatigue is currently worse from fasting.” Another member described concerns about “putting more stress on my body.” “I feel worse when I fast,” said a third member. “I have terrible tremors, and a lack of food just makes them worse.”

Potential Benefits of Fasting for MS

Many people living with MS wonder if intermittent fasting can ease their symptoms. Only disease-modifying therapies are proven in scientific studies to treat MS itself — to reduce flares and slow disease progression. There is no evidence that diets and fasting can cure or slow MS, but healthy eating can help you feel better overall. Any diet plan should only be used in combination with the treatment plan you devise with your neurologist.

Research on fasting for people with MS is still in the early stages. One small clinical trial of 31 people with MS found intermittent fasting was a safe and effective way for people with MS to lose weight over two months. It also led to better emotional health and reduced the participants’ levels of memory T cells. T cells are involved in the immune response in MS. The long-term impact of these findings are still unclear, and more research is needed.

Research is ongoing to discover the connections between fasting, gut health (gut microbiome bacteria), and the immune system in people with MS. At this point, there is not enough data to draw any conclusions. It’s important to note that the few studies done so far have lasted only a few months, and they haven’t examined whether effects last beyond the end of the diet or deliver long-term results.

Potential Risks of Intermittent Fasting

There are several risks of intermittent fasting, and they can range in severity.

Known risks of intermittent fasting include:

• Headaches
• Low energy or fatigue
• Constipation
• Binge eating or overeating between fasts
• Lack of necessary nutrients
• Dehydration
• Losing too much weight
• Mood swings and mental health challenges

If you are predisposed toward eating disorders, intermittent fasting can be risky. It can also be dangerous to fast if you take certain medications or have certain medical problems, such as diabetes. Fasting improperly with a medical condition could lead to a life-threatening emergency. It’s critical to always talk to your doctor before deciding to fast or making changes to your diet.

Talk With Others Who Understand

MyMSTeam is the social network for people with MS and their loved ones. On MyMSTeam, more than 198,000 members come together to ask questions, give advice, and share their stories with others who understand life with MS.

Have you tried intermittent fasting or talked to your doctor about it? Share your experience in the comments below, or start a conversation by posting on your Activities page.