- Women with vitamin D deficiency were more likely to have moderate-to-severe pain in the first 24 hours after breast cancer surgery and used more opioid medication.
- The new study builds on a growing body of research suggesting vitamin D plays a role in how the body senses and regulates pain.
- Other studies reinforce the link but caution that controlled trials are needed before vitamin D can be recommended as a pain treatment.
Evidence continues to grow that vitamin D could help manage pain, something that has been suggested for some time.
In a just-published study in the journal Regional Anesthesia & Pain Medicine, a group of researchers from Egypt found that women who have low levels of vitamin D experienced more pain and sought “significantly more” opioid medication after undergoing breast cancer surgery. But the findings are believed to have broader implications than breast cancer surgery and actually build on similar results from a diverse array of studies.
The researchers, from the Fayoum University faculty of medicine, concluded that a deficiency in vitamin D was associated with a “higher occurrence of moderate to severe postoperative pain and increased opioid consumption in patients” who had undergone the surgery. They concluded patients facing breast cancer surgery would benefit from supplementing vitamin D prior to the operation.
But per Science Daily, the findings go beyond that surgery. The team noted that evidence is mounting that vitamin D is important to how the body senses and regulates pain. “Scientists believe this may be connected to the vitamin’s anti-inflammatory properties and its effects on the immune system.”
What is vitamin D good for?
It has long been known that vitamin D helps the body absorb calcium and the two together help prevent osteoporosis. The National Institutes of Health calls the vitamin vital for nerves, so they can carry messages between the brain and body. It also helps the immune system combat viruses and bacteria.
Sunshine is not the only way to get vitamin D. Fortified milk contains vitamin D. Fatty fish and fish liver oils provide decent amounts. You can get a little from beef liver, egg yolks and cheese. Mushrooms that were exposed to ultraviolet light also have vitamin D.
The study’s design
For this research, 184 female patients who were scheduled to undergo elective one-sided modified radical mastectomy were tested to determine their vitamin D levels and were sorted into two groups: those with sufficient vitamin D and those who were deficient.
The doctors and nurses had no idea whether a patient had enough vitamin D or not. They were all treated the same, including receiving fentanyl during the surgery. Afterward, they each got intravenous acetaminophen for eight hours, but could self-administer tramadol, another opioid pain medication, by pushing a button. There were, of course, limits.
Pain levels were noted right after surgery and every six hours up to 24 hours after surgery. Vomiting, nausea, sedation level and how long they were in the hospital was also tracked.
“Patients with vitamin D deficiency were three times more likely to experience moderate to severe pain during the first 24 hours after surgery compared with patients who had adequate vitamin D levels,” per the study. The difference was in moderate pain; none of the patients in either group had severe pain. But to keep pain under control, the vitamin D-deficient group used additional opioid medication.
In the study, those who were deficient in vitamin D also experienced more of the side effects and none of those with adequate vitamin D vomited after surgery, though even among them it was uncommon.
There were limitations. The study was observational and small, confined to one treatment center, so researchers can’t say for certain that vitamin D deficiency was directly to blame for the higher pain level. They didn’t measure confounders that could account for the finding, like increased inflammation or whether people had depression, or sleep problems, among other factors that could influence pain.
Even so, they concluded that the deficiency was linked to the higher levels of moderate to severe pain.
Vitamin D and pain management
Opioids can control pain, but they may also have side effects, including nausea, vomiting, drowsiness and confusion. There’s also risk of overdose and/or addiction.
A study from Sweden in the International Journal of Molecular Sciences describes vitamin D as a hormone synthesized in the skin in the presence of sunlight and notes that it plays a role “in a wide range of processes in the body.”
Including, possibly, in pain. “In observational studies, low vitamin D levels have been associated with increased pain and higher opioid doses,” the researchers wrote. “Recent interventional studies have shown promising effects of vitamin D supplementation on cancer pain and muscular pain — but only in patients with insufficient levels of vitamin D when starting intervention.”
They are among researchers who suggest that vitamin D reduces inflammation, among other possible mechanisms of pain relief. Per their study, “Our conclusion is that vitamin D may constitute a safe, simple and potentially beneficial way to reduce pain among patients with vitamin D deficiency, but that more randomized and placebo-controlled studies are needed before any firm conclusions can be drawn.”
They add that vitamin D supplementation has not caused adverse effects. And it’s easy to administer.
A UK study also looked at vitamin D levels, this time in cases where people have chronic pain. Published in the journal Therapeutic Advances in Musculoskeletal Disease, the researchers reviewed numerous studies linking vitamin D deficiency to pain and noted that while there’s growing evidence of it, it’s not clear how it prevents or ameliorates chronic pain.
But there’s no question, per the British team’s review of data, that pain is influenced by vitamin D insufficiency and that supplementing it could offer “numerous health benefits.” But they added that it’s not ready, however, to be used as an effective treatment on its own for chronic pain.