Appendix: Vitamin B and Vitamin D

People living with HIV often have lower than normal levels of micronutrients, and healthcare providers often recommend that everyone with HIV take a complete multivitamin-mineral supplement daily to maintain optimal levels. However, two specific vitamins, vitamin B and vitamin D, are of particular concern because of their many effects in the body.

Vitamin B₁₂

A large percentage of people living with HIV have vitamin B₁₂ deficiency, which can begin early on. Vitamin B₁₂ deficiency can result in neurologic symptoms — for example, numbness, tingling and loss of dexterity — and the deterioration of mental function, which causes symptoms such as foggy thinking, memory loss, confusion, disorientation, depression, irrational anger and paranoia. Deficiency can also cause anemia. It has also been linked to lower production of the hormone melatonin, which can affect the wake-sleep cycle.

If you have developed any of the emotional or mental symptoms mentioned above, especially combined with chronic fatigue, vitamin B₁₂ deficiency could be contributing. This is especially true if you also have other symptoms that this deficiency can cause, including neuropathy, weakness and difficulty with balance or walking. On the other hand, these symptoms can also be associated with HIV itself, with hypothyroidism, severe anxiety, depression or an advanced stage of syphilis called neurosyphilis. A thorough workup for all potential diagnoses is key to determining the cause.

The dose of vitamin B₁₂ required for supplementation varies from individual to individual, and working with a healthcare provider is recommended to determine the correct dose. Vitamin B₁₂ can be taken as a pill, by nasal gel or by injection. The best way to take it depends on the underlying cause of the deficiency, so it’s important to be properly assessed before starting supplements. For oral therapy, a typical recommendation is 1,000 to 2,000 mcg daily.

One way to know if supplementation can help you is to do a trial run of vitamin B₁₂ supplementation for at least six to eight weeks. If you are using pills or sublingual lozenges, the most useful form of vitamin B₁₂ is methylcobalamin. Talk to your healthcare provider before starting any new supplement to make sure it is safe for you.

Some people will see improvements after a few days of taking vitamin B₁₂ and may do well taking it in a tablet or lozenge that goes under the tongue. Others will need several months to see results and may need nasal gel or injections for the best improvements. For many people, supplementation has been a very important part of an approach to resolving mental and emotional problems.

Vitamin D

Some studies show that vitamin D deficiency, and often quite severe deficiency, is a common problem in people living with HIV. Vitamin D is intimately linked with calcium levels, and deficiency has been linked to a number of health problems, including bone problems, depression, sleep problems, peripheral neuropathy, joint and muscle pain and muscle weakness. It is worth noting that, in many of these cases, there is a link between vitamin D and the health condition, but it is not certain that a lack of vitamin D causes the health problem.

A blood test can determine whether or not you are deficient in vitamin D. The test measures levels of the storage form – vitamin D₂. If you are taking vitamin D (usually this is in the form of vitamin D₃), the test will show whether you are taking a proper dose for health, and reduce the risk of taking an amount that could be toxic (although toxicity from vitamin D₃ is highly unlikely, even in large doses up to 10,000 IU daily when done under medical supervision over the medium term). The cost of the test may not be covered by all provincial or territorial healthcare plans or may be covered only in certain situations. Check with your healthcare provider for availability in your region.

The best test for vitamin D is the 25-hydroxyvitamin D blood test. There is some debate about the best levels of vitamin D, but most experts believe that the minimum value for health is at least 70 nmol/l. Many people use supplements to boost their levels to around 100 nmol/l. Vitamin D levels fall during winter and during periods of infections cold, flu and COVID-19. 

While sunlight, salmon and fortified foods are possible sources of vitamin D, the best way to get adequate levels of this vitamin is by taking a supplement. The best dose to take depends on the person. A daily dose of 1,000 to 2,000 IU is common, but your healthcare provider may recommend a lower or higher dose for you, depending on the level of vitamin D in your blood and any health conditions you might have. People should not take more than 4,000 IU per day without letting their healthcare provider know. Look for the D₃ form of the vitamin rather than the D₂ form. Vitamin D₃ is the active form of the vitamin and there is some evidence that people living with HIV have difficulty converting vitamin D₂ to vitamin D₃. Vitamin D₃ supplements are less commonly associated with toxicity than the D₂ form. Some people living with HIV may take months or even years to reach adequate levels of vitamin D in their blood despite taking several thousand units per day of vitamin D₃. This slow rate of replenishment may occur because of inflammation or other conditions. Medicines that can reduce vitamin D levels include HIV protease inhibitors, drugs used to prevent or treat anxiety, depression, inflammation and seizures. Corticosteroids (also known as glucocorticoids) can also reduce vitamin D levels.

It is best to do a baseline test to know your initial level of vitamin D. Then, have regular follow-up tests (usually once a year) to see if supplementation has restored vitamin D to an optimal level. Regular testing is the only way to be sure you attain — and maintain — the optimal level for health.

With proper supplementation, problems caused by vitamin D deficiency can usually be reversed.