Vitamin D and Lupus

What is lupus?

Systemic lupus erythematosus (SLE), or lupus, is a chronic disease that affects many systems in the body, such as the skin, heart and muscles. Lupus develops when an individual’s immune system begins to function abnormally. SLE is an autoimmune disease, which means that the immune system has a hard time telling the difference between its own healthy cells and foreign substances like germs, bacteria or viruses. This causes the body to attack its own healthy tissue, which can cause inflammation and pain. It is common for people with lupus to have periods of flares, characterized by increased symptom severity, and periods of remission, when the symptoms have improved or disappeared completely. When lupus symptoms are flaring up, the disease is considered “active”. Lupus can be hard to diagnose, because many of the symptoms are similar to other autoimmune diseases¹.

How common is lupus?

About 5 million people around the world have some type of lupus. SLE mostly affects women of reproductive age, but men and children can also develop the disease. There are some risk factors that increase your chances of getting lupus, such as:[1]

• Gender: 9 out of 10 people who have lupus are females.
• Race: African-Americans are three times more likely to develop lupus than Caucasians. Other races that have an increased risk are Hispanics, Native Americans, Asian-Americans and Pacific Islanders.
• Age: Lupus usually develops between the ages of 15 and 45.
• Genetics: Family history of lupus increases the risk of developing lupus.
• Smoking: Some research has shown that smoking may increase one’s chances of developing lupus.

What are the symptoms of lupus?

Since lupus can affect so many different body systems, there is a wide range of symptoms that can vary from person to person. The most common symptoms include: [2],[3]

• Fatigue
• Fever
• Joint and muscle pain
• Chest pain
• Swelling in feet, legs, or hands
• Rashes
• Sensitivity to the sun
• Hair loss
• Sores in the mouth or nose

Some people with lupus might have symptoms that involve specific body parts, such as:

• Digestive system: nausea, vomiting, stomach pain
• Heart: People with lupus have increased chances of developing heart disease, because it can cause inflammation around the heart or a buildup of plaque in the blood vessels.
• Lungs: Difficulty breathing
• Nervous system: Headaches, numbness or tingling, problems with eyesight and seizures
• Bones: People with lupus have increased chances of bone fractures or developing osteoporosis.[4]

What causes lupus?

It is not fully understood what causes lupus or how it develops. Researchers think that lupus is caused by a combination of genetics, hormones and the environment. Since most of the people with lupus are female, it is possible that estrogen might play a role in SLE. Most researchers believe that lupus results when an environmental trigger interacts with an individual who is genetically predisposed to the disease. In lupus, environmental triggers can also cause the disease to flare up. The immune system will start making proteins called auto-antibodies, which is what will attack the healthy cells in the body, causing inflammation and pain¹. The most common environmental triggers that can cause lupus flares include¹:

• UVB light
• Infections or viral illnesses
• Exhaustion or emotional stress
• Stress to the body, such as surgery, pregnancy or trauma
• Some medications

What is the link between lupus and vitamin D?

Many studies have shown that there is a link between vitamin D and lupus. People who have lupus are more likely to have low levels of vitamin D. In addition, disease severity has been linked to low vitamin D levels. This may be because people with lupus are sensitive to the sun, so they often either wear high SPF sunscreen or avoid being outdoors. However, researchers think that not getting enough vitamin D may also be an environmental trigger that increases the risk of having a flare up and increases the chances of developing lupus.[5] Vitamin D receptors are found on the surface of a cell where they receive chemical signals. By attaching themselves to a receptor, these chemical signals direct a cell to do something. For example, to act in a certain way, divide or die. There are vitamin D receptors found on cells in the immune system, and vitamin D can bind to these receptors. This can cause the auto-antibodies to decrease and stop attacking the healthy cells in the body. Therefore, it is believed that vitamin D can help prevent lupus flares by reducing inflammation in the body.[6],[7],[8] In addition, when one has systemic lupus, vitamin D does not limit production of B cells and T helper cells. B cells produce antibodies which are associated with disease activity, and T helper cells are pro-inflammatory.[9] While it is thought that having enough vitamin D can help prevent flares in people who have lupus, more experiments need to be done to determine definitively if taking vitamin D supplements can help prevent or treat lupus. Research hasn’t been able to show yet that low vitamin D levels cause lupus.

What does the research say in general about vitamin D and lupus?

Preventing lupus

Most research on lupus prevention hasn’t been able to find a clear link between vitamin D and lupus. A study that followed a large group of women for many years found that there was no link between vitamin D intake or sun exposure in adolescence and their chances of developing lupus later in life. However, the researchers didn’t look at vitamin D levels in the body and only relied on what the women could remember about how much vitamin D they consumed or sunlight to which they were exposed.[10] More studies are needed to determine if there is a link between vitamin D levels during childhood and adolescence and the chances of developing lupus later in life.

Managing and treating lupus

People with lupus are very likely to have low levels of vitamin D. This may be because people with lupus are sensitive to the sun, so they often avoid being outdoors or wear high SPF sunscreen. Those with active lupus often take medications that can interfere with vitamin D in their body, which may make them more likely to become vitamin D deficient.[11] Studies have shown that people with higher levels of vitamin D have fewer lupus symptoms. Those living in places where there is more sunlight have a lower risk of developing autoimmune diseases.[12] African-Americans with lupus have been found to have lower levels of vitamin D than Caucasian people with lupus.[13] Researchers have found that in winter months with low sunlight, people with lupus are more likely to have active symptoms, as well as more likely to have low levels of vitamin D. People with lupus are also more likely to have more flares during low sunlight months compared to high sunlight months.[14] In a systematic review, the majority of studies showed that people with lower levels of vitamin D were more likely to have more severe lupus symptoms. Severity of lupus symptoms is related to increased risk of damage to other organs, like the heart or kidneys.[15] To date, most of the research that has been conducted is observational, meaning that researchers can’t say for sure whether or not low levels of vitamin D cause lupus, or if it is having lupus that causes low levels of vitamin D.

What does recent research say about vitamin D and lupus?

An experiment conducted in Egypt in 2012looked at vitamin D levels and symptoms in people with lupus before and after supplementing with vitamin D. There were 2 groups in this study. The first group received 2,000 IU of vitamin D per day for 12 months, and the second group got a placebo pill. The researchers found that:[16]

• The people in the vitamin D group had an improvement in lupus symptoms and had fewer flare occurrences, compared to the people who received the placebo pill.
• Vitamin D levels were lowest in those who had the most active lupus.
• People in the vitamin D group had lower levels of inflammation in their body than those getting the placebo pills.

This study shows that having low levels of vitamin D may result in increased severity of lupus activity, symptoms and flares. The researchers suggested that vitamin D may help to normalize the immune system in people with lupus. They concluded with a recommendation that people with lupus could benefit from supplementing with vitamin D, but also that more trials are needed to confirm these results. An experiment published in 2014looked at people with cutaneous lupus erythematosus, a form of lupus that only affects the skin. The researchers first looked at vitamin D levels in people with lupus compared to people who didn’t have the disease. Then, they gave vitamin D supplements to the subjects with lupus who had low vitamin D levels. The researchers administered 1,400 IU vitamin D with 1,250 mg calcium per day for 40 days, then 400 IU with 1,250 mg calcium twice a day for 1 year after that. They found that:[17]

• Vitamin D levels were lower in the people with lupus compared to the people without lupus.
• The people who were given the vitamin D supplements had significant improvements in their lupus disease activity, as well as lower numbers of lesions on their skin.

The number of exacerbations decreased from 2.8 to 1.7 per year in the treatment group and from 2.0 to 1.7 per year in the control group. The baseline vitamin D level in the treatment group was 17 ng/mL, and 60% of those treated with vitamin D reached levels above 30 ng/mL after treatment. The vitamin D dose used in this study is lower than many vitamin D researchers now recommend. An experiment conducted in 2012 in Francelooked at subjects with lupus who had low levels of vitamin D. The researchers administered 100,000 IU vitamin D per week for 4 weeks, followed by 100,000 IU vitamin D per month for 6 months. Afterwards, they looked at the participant’s vitamin D levels and at different cells in the body that can cause the immune system to act differently. They found that:[18]

• After supplementing with vitamin D, the individuals with lupus had lower levels of cells that cause the immune system to make more antibodies, which is what causes the body to attack its own healthy cells.
• Those who took the vitamin D supplement also had higher levels of cells that can help to regulate the production of antibodies. In people with lupus, these cells can help to prevent the body from attacking its own healthy tissue.

The researchers stated that vitamin D supplementation may help the immune system function more normally in people with lupus. A study published in 2014 followed a large group of people with lupus from 7 different countries in North America, Europe and Asia. The researchers looked at their vitamin D levels, lupus disease activity levels and heart disease risk factors. They followed the participants for over 6 years and found that:[19]

• The people with the highest vitamin D levels had the lowest levels of lupus disease activity.
• The people with the lowest levels of vitamin D had higher blood pressure, amounts of fat in the blood and levels of a protein related to heart disease risk.
• The people with the highest levels of vitamin D were less likely to have an illness related to the heart, such as a heart attack or stroke.

This study was observational, which means that the researchers can’t say for sure that having low vitamin D levels caused the people to develop heart disease. A vitamin D supplementation study conducted in 2015 looked at children of mean age 10 years (26 girls, 2 boys) with lupus in Saudi Arabia with baseline vitamin D level of 20.4±13.6 ng/mL (51±34 nmol/L). Most of the patients had been taking 800 IU/d vitamin D3 prior to the study. High autoantibodies, a high protein/creatinine ratio and subnormal bone density were observed in the majority of the children. After three months of treatment with 2000 IU/d vitamin D3 plus 1200 mg/d calcium, 17 of the 28 patients had improvements in the lupus disease activity index (global index that assesses SLE disease severity) and autoimmune markers.[20]

Key points from the research

• People who have lupus are more likely to have low levels of vitamin D.
• Those with lupus who have higher levels of vitamin D tend to have less lupus disease activity, symptoms and flares.
• There are higher rates of lupus flares in winter months than in summer months.
• People with lupus who have low levels of vitamin D are more likely to have risk factors that increase their chances of developing heart disease than those with high levels of vitamin D.
• Supplementing with vitamin D results in fewer lupus symptoms and less inflammation in the body.
• Overall, more experiments are needed to provide a clearer explanation about how helpful vitamin D supplements are in the treatment or management of lupus and what the dose should be.

What does this mean for me?

Research has shown that there is a link between vitamin D and lupus. Individuals with lupus are more likely to have low levels of vitamin D, which is linked to more severe symptoms and outcomes, like heart disease. Three studies have shown that giving vitamin D supplements to people with lupus can help improve their symptoms and reduce the number of flare-ups. More research is needed to see just how effective vitamin D might be for lupus treatment, if at all. Research has not determined that low vitamin D levels cause lupus, or whether supplementing with vitamin D will help prevent lupus. If you have lupus and want to take vitamin D, it is unlikely to make your condition worse or cause you any harm, as long as you take less than 10,000 IU per day. However, it’s not proven that taking vitamin D will help to treat your lupus. If you have lupus, you shouldn’t take vitamin D in place of your treatment medications. Talk to your physician for more advice about taking supplements.

If I have lupus, can I get sun exposure?

Sunlight can often worsen lupus skin symptoms, so people with lupus are advised to wear sunscreen or avoid the sun during the middle of the day. Avoiding the sun and wearing sunscreen also means that you can’t get the vitamin D you need from the sun. If you have lupus and are sensitive to the sun, the best way to get vitamin D is from supplements.

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