People living with HIV have an increased risk of insufficient vitamin D levels, or a vitamin D deficiency. This may be due to side effects of antiretroviral therapy, which is any HIV treatment that combines two or more drugs.
Research from 2019 notes that vitamin D deficiency is common across the globe and affects over 75% of the population in the United States. However, it is particularly common in people living with HIV.
Supplementing vitamin D may help restore its levels in HIV-positive people.
In this article, we look at the link between HIV and low vitamin D levels. We also discuss the effects of vitamin D supplementation.
People living with HIV may have an increased risk of vitamin D deficiency.
There are several
- lack of sun exposure
- lack of dietary sources of vitamin D or malabsorption
- dark skin pigmentation
- intravenous drug use
- liver disease
- kidney disease
- older age
People living with HIV may also have an increased risk of vitamin D deficiency due to:
- certain antiretroviral therapy
- chronic inflammation
- immune activation
- the effect of HIV proteins on enzymes that play a role in vitamin D production in the body
HIV-1 affects how the body metabolizes vitamin D. HIV-1 can cause an increase in pro-inflammatory cytokines, a type of protein that prevents the body from synthesizing active vitamin D.
Certain antiretroviral therapies may also have an impact on vitamin D levels in the body.
According to a
Efavirenz also appears to decrease vitamin D levels. A
Tenofovir disoproxil fumarate (TDF) may also affect how the body metabolizes vitamin D, and it may increase the likelihood of bone loss.
Vitamin D plays an important role in the body’s immune response, which is how the body reacts to foreign or harmful substances and infections.
Researchers still need more evidence to determine whether regular vitamin D supplementation can prevent or alter the course of inflammatory or autoimmune conditions in people at risk.
The article concludes that vitamin D plays an important role in immune function and that avoiding vitamin D deficiency helps improve immune health and decreases the risk of autoimmune conditions.
Doctors can monitor vitamin D in HIV-positive people to ensure they have sufficient levels.
If a person is taking certain antiretrovirals that decrease the amount of vitamin D in the body, they may consult their doctor about a change in antiretroviral therapy.
The Department of Health and Human Services suggests changing certain drugs, if possible, such as switching from TDF to tenofovir alafenamide (TAF). If individuals are using TDF, they may need to use a vitamin D3 supplement.
The source recommends people on antiretroviral therapy take up to 4,000 international units (IU) of vitamin D3 daily.
Authors of a 2019 review of 29 clinical studies report that vitamin D supplementation can effectively restore sufficient levels of the vitamin in people with HIV who have low vitamin D levels or vitamin D deficiency.
The studies included daily doses ranging from 400 to 14,000 IU. Doses between 4,000 and 7,000 IU were the most common.
In severe cases of vitamin D deficiency, a daily dose of 7,000 IU turned out to be the most effective across the studies. Supplementation at this level restored vitamin D to a sufficient level in 80% of the participants, with levels increasing after 12 months of treatment.
Once people reached a sufficient amount of vitamin D in the body, researchers recommended a maintenance dose to keep vitamin D levels stable.
However, high doses of vitamin D may pose risks. If calcidiol, which is a form of vitamin D, increases beyond 100 nanograms per milliliter (ng/ml), or if calcium in the blood increases beyond 2.70 millimoles per liter (mmol/l), it could produce adverse effects.
Nine of the trials included vitamin D supplementation that exceeded the recommended upper limit of 4,000 IU per day. Among all of the studies in the review, all supplementation turned out to be safe, with no reports of adverse effects.
However, each of the studies had a relatively short follow-up period, and therefore further research may provide more details about the long-term effects and safety of vitamin D supplementation.
Vitamin D supplementation can help increase vitamin D levels in people with HIV-1 who have a vitamin D deficiency. Supplementation has proven effective regardless of:
- combination antiretroviral therapy
- geographical location
In addition to preventing symptoms of deficiency, increased vitamin D levels may reduce the risk of potential HIV complications, such as:
- microbial infections, such as tuberculosis
- chronic inflammation
- bone turnover, which is when the body reabsorbs old tissue and forms new bone tissue
Additionally, supplementation may increase the amount of the type of lymphocytes that HIV destroys, which are cells that help stimulate and regulate the immune system.
Researchers are still unclear about whether vitamin D supplementation has any effect on viral load, which is the amount of HIV per ml of blood.
Vitamin D deficiency is common in people living with HIV. This may be due to a combination of the direct effects of HIV on the body and of antiretroviral therapy, both of which can suppress the body’s ability to produce vitamin D.
Many studies have shown that vitamin D supplementation is safe for people living with HIV and that it can effectively restore sufficient levels of the vitamin.