Vitamin D Levels and Lupus

People with lupus often have low levels of Vitamin D, a nutrient that is vital for bone strength and immune function.

Human beings get vitamins from the things we eat and from exposure to sunlight. However, people with systemic lupus erythematosus (SLE) often have low levels of vitamin D. This is in part due to being sensitive to UV light and not being able to tolerate sunlight, a source for vitamin D.

Vitamin D is vital to the body, but may be even more key for people with lupus. Studies on people with chronically low levels of vitamin D have revealed an interesting possibility: that vitamin D deficiency might be one of the triggers of lupus, or a reason why the symptoms get worse over time.

It’s clear that vitamin D is vital for people with lupus, but what exactly is it? And how can you get more of it?

What is Vitamin D?

Vitamin D or calciferol, is the precursor of a hormone called calcitriol that is important to calcium regulation in the body. It has many important roles in bone development, immune system activity, and the function of the brain and nervous system.

Vitamin D actually refers to two slightly different compounds:

1. D2 which is acquired through their diet
2. D3 which is produced in the skin through exposing ergosterol (which is derived from plants) to the ultraviolet light of the sun.

Not getting enough vitamin D can lead to a disease known as rickets in children and to bone issues such as osteoporosis in adults. You can read about osteoporosis and lupus here.

Good dietary sources include:

• oily fish
• liver
• egg yolks
• certain types of mushrooms

Fortified foods also contain more vitamin D than non-fortified versions. This makes them useful for people who do not eat animal products.

Once produced or digested, vitamin D travels to the liver. The liver breaks the vitamin down into an inactivated version of the hormone. From there, these dormant hormones travel to the brain, kidneys, prostate, and immune system cells. In pregnant women, it also travels to the placenta.

Vitamin D is then activated at these organs in slightly different ways, including regulating calcium:

• Kidneys
  • Vitamin D ensures that calcium doesn’t get filtered out too much, or to a dangerous degree.
• Brain and nervous system
  • Vitamin D assists the neurons with proper calcium metabolism, aiding the transmission of signals.
• Immune system and in certain other areas in the body (such as the brain and lungs)
  • Vitamin D helps to modulate the immune response and protect the body.

While all of these are important for people with lupus, the immune system effects of vitamin D could have a relation to lupus symptoms and flares.

Vitamin D and Lupus

In the body, vitamin D is an immune system modulation hormone. The vitamin acts a lot like cytokines  (immune system chemicals that help the immune system cells communicate to each other).

Vitamin D encourages the growth and production of immune system cells. While it can trigger T cells to divide and act, vitamin D can also inhibit the growth and production of T cells and inflammatory cytokines. Because it does both, vitamin D is important to proper immune system function.

Cytokine production and inflammation are natural parts of life with lupus. Modulating the immune system is key to treating lupus.

Low levels of vitamin D are found consistently across the board in people with lupus.

Some have wondered if low levels of vitamin D can cause lupus, and it may contribute. This is difficult to determine, however. In a randomized study of people with lupus, low vitamin D levels did not seem to be linked to an increased risk of developing lupus. However, people with lupus may have vitamin D deficiencies because of their lupus.

Many factors limit absorption of vitamin D into the blood stream including:

• limited time outdoors
• photosensitivity (and protection from sunlight like clothes and sunscreen)
• corticosteroids
• issues with kidney function

You can read more about photosensitivity and lupus here.

Should You Take Vitamin D Supplements?

Does vitamin D have a definite effect? That’s hard to determine.

People with SLE often have issues with bone health, including increases in fracture and osteoporosis and vitamin D can help.

Larger studies (763 patients in this case) found that supplementation with vitamin D and calcium helped reduce symptoms (as measured by SLEDAI scores.)

The exact relationship between vitamin D and lupus symptoms is hard to define. Taking supplements and otherwise getting a good amount of vitamin D (ideally both types) can help by improving overall health or by alleviating the comorbidities of lupus.

In particular, vitamin D is involved with cardiovascular health, which affects many symptoms of lupus. Heart problems or poor circulation can affect the severity of symptoms of fatigue and brain fog.  As mentioned before, vitamin D and calcium supplements can help offset bone problems associated with lupus.

Before starting any new supplements or changing your treatment plan, speak with you lupus care team