Many people are interested in using vitamins and supplements to help manage autoimmune diseases like multiple sclerosis (MS). In autoimmune diseases, the immune system mistakenly attacks the body’s healthy cells, causing inflammation and other symptoms. Vitamin C plays many important roles in your body, and for some people, supplementing vitamin C may improve overall health.

Although other animals make vitamin C in their bodies, humans don’t. That means you need to get it from other sources, primarily your diet. We know vitamin C is necessary for producing certain neurotransmitters (chemicals nerves use to communicate), so we know that vitamin C is active in the nervous system. Does that mean taking extra vitamin C might be beneficial for MS? Can taking vitamin C supplements cause any potential risks?

In this article, we’ll explore what research has uncovered about the relationship between vitamin C and MS.

What Is Vitamin C?

Vitamin C, also called L-ascorbic acid, is an essential part of your diet. It’s a water-soluble vitamin, which means it dissolves in water. When you consume vitamin C in foods or as a dietary supplement, it travels through your tissues to support healthy bodily functions. Vitamin C is an essential element, but you only need it in small amounts.

Vitamin C for Protein Building

Vitamin C is an ingredient of various proteins in your body including collagen. Think of collagen as a building block of connective tissue. When you’re injured, vitamin C supports the healing process.

Vitamin C as an Antioxidant

Antioxidants like vitamin C protect your cells from damage and may help slow the aging process. In addition to being an antioxidant itself, vitamin C also supports the function of other antioxidants like vitamin E. Further research is needed to determine if vitamin C as an antioxidant helps prevent or delay certain long-term diseases like heart disease and specific types of cancer.

Vitamin C for Immunity

Vitamin C is also active in the immune system. It’s a common ingredient in immune-support supplements because it helps immune cells protect you from disease-causing germs.

Where To Get Vitamin C

Healthy eating for MS is important for the health and function of your nervous system, and you can get vitamin C from many fruits and vegetables. A few rich sources of vitamin C include:

• Red bell peppers
• Oranges and other citrus fruits
• Kiwis
• Green peppers
• Strawberries
• Brussels sprouts
• Broccoli
• Spinach

Cooking vitamin C-rich veggies may reduce their vitamin C content, so you’ll get the most vitamin C by eating them raw. You can also get vitamin C by taking vitamin C dietary supplements or, in some specific settings, getting vitamin C intravenous (into a vein) infusions.

Vitamin C Deficiency

Because vitamin C supports healthy bodily functions, low levels of vitamin C can cause serious problems. Not getting enough vitamin C can lead to scurvy and poor immunity, which increases your risk for infections.

Scurvy causes a wide range of symptoms and health concerns including:

• Fatigue
• Joint pain
• Irritability
• Anemia
• Gum disease
• Rough skin
• Easy bruising

Scurvy only occurs as a result of vitamin C deficiency, and it’s rare in the United States and other countries because most people get enough vitamin C in their diets. Smoking is a risk factor for vitamin C deficiency, as it reduces your absorption of vitamin C. You’re also at a higher risk if you eat very little due to medical conditions like anorexia or medical treatments like chemotherapy.

Can You Have Too Much Vitamin C?

If you consume more than you need in a day, any excess vitamin C leaves your body in your urine. However, taking more vitamin C than your digestive tract can absorb can cause side effects including:

• Nausea
• Diarrhea
• Stomach cramps

In some people, taking too much vitamin C might cause kidney stones. High doses of vitamin C may make certain health conditions worse.

Vitamin C and MS

Some MyMSTeam members have shared their experiences taking vitamin C to feel better with MS. “Vitamin C is working well for me,” wrote one member. “I haven’t walked this good in months.” Another said, “I've had some success taking large quantities of vitamin C for bladder issues.”

Here’s what research says about MS and vitamin C.

Potential Benefits of Vitamin C for MS

Because vitamin C plays an important role in building collagen, it’s also involved in the formation of myelin. Myelin is a fatty coating around your nerve fibers that protects and insulates them. It allows nerve signals to travel quickly. When you have MS, your immune system damages the myelin around the nerves in your brain and spinal cord.

Research shows that vitamin C helps rebuild myelin around peripheral nerves after damage from injuries. It helps Schwann cells, the cells responsible for creating myelin in your peripheral nervous system, create myelin to insulate nerves. Other brain cells build myelin in your central nervous system (CNS), but are damaged by your immune system if you have MS. In a study on mice, vitamin C helped rebuild myelin in the CNS. More research is needed to determine if vitamin C supplements can help rebuild CNS myelin in humans with MS.

Vitamin C is an antioxidant, and there’s some evidence that antioxidant vitamins are beneficial for MS and other neurodegenerative diseases. Limited research suggests that oxidant activity in the CNS is responsible for some MS-related damage, and antioxidants might protect your CNS from such damage. More large-scale clinical trials are needed to confirm any benefits of antioxidants for MS.

Potential Risks of Using Vitamin C for MS

Although vitamin C has possible benefits for people with MS, there are risks of using large doses. High doses of vitamin C can cause what’s called the Fenton reaction in your brain and spinal cord. The Fenton reaction causes inflammation and might make inflammatory diseases like MS worse.

Because MS is an autoimmune disease, some antioxidants may be risky because they stimulate the immune system. This could cause MS symptoms to get worse. One MyMSTeam member said, “I’m worried about taking anything that would boost my immune system since with MS, our immune response is already overactive.”

Using Vitamin C for MS

You can usually get enough antioxidants by eating two to four servings of fruit and three to four servings of vegetables each day. According to the journal Nutrients, the recommended daily vitamin C intake is 75 milligrams for women and 90 milligrams for men. If you smoke, you should increase your daily vitamin C intake by at least 35 milligrams beyond the standard recommendation. There’s no clear evidence that you should supplement your vitamin C intake due to your MS.

If you’re thinking about purchasing vitamin supplements or getting vitamin infusions, talk to your neurology team first. They can tell you of any possible medication interactions or side effects and help you use vitamins and supplements safely.

Talk With Others Who Understand

MyMSTeam is the social network for people with MS and their loved ones. On MyMSTeam, more than 216,000 members come together to ask questions, give advice, and share their stories with others who understand life with MS.

Have you taken vitamin C supplements to manage MS symptoms or support your overall health? Have you noticed any changes? Share your experience in the comments below, or start a conversation by posting on your Activities page.