The Guide to Supplements for Rheumatologic Diseases

Many people with rheumatologic diseases try supplements for symptom relief. Here’s what you need to know about some common picks.

Dietary supplements were a $159 billion business in the United States last year, and many people with rheumatologic diseases are buying in. Research suggests more than 6 in 10 people with fibromyalgia, nearly 8 in 10 people with Sjögren disease, and more than 8 in 10 people with rheumatoid arthritis (RA) take dietary supplements.

Whatever the symptom — pain, swelling, or fatigue — you can probably find a supplement purporting to relieve it. But do these supplements work, and are they safe? A study review in RMD Open comprising 24 systematic reviews and 150 original articles suggests more high-quality research is needed on the effects of dietary supplements on rheumatologic diseases. Most studies have focused on RA or osteoarthritis (OA), where the evidence level is moderate at best.

“The studies in this space are usually not very high quality because there’s no money to support them, among other things, plus the products are disparate,” said Janet Funk, MD, MS, professor in the School of Nutritional Sciences and Wellness at the University of Arizona, Tucson, Arizona. She recommended brushing up on supplements and finding out what patients are taking so you can offer advice and watch for drug-supplement interactions.

When asked for a medication list, many patients forget to report supplements, Funk said. “You have to prompt them specifically,” she said. “I think some physicians have very negative views about supplements because so little data is known, and patients might pick up on that and decide not to report their use.” Say something like: To give you the best possible care, I want to know everything you’re taking, including supplements. The things I’m prescribing could maybe interact with the things you’re taking, so I want to make sure I know about all of it so that together we can figure out if the combination of things is safe.

The quality of dietary supplements varies, and they aren’t regulated like drugs by the US Food and Drug Administration. Funk recommended selecting products verified by NSF or ConsumerLab. They test supplements to ensure the label reflects what’s inside.

We scoured the literature and asked experts to weigh in on the evidence behind popular supplements in rheumatology today.

SUBHEAD – The Essential Nutrients

Vitamin supplements are a staple in many homes — but are they helpful? “Individual vitamin supplements will not provide any benefit unless the person is deficient in a specific vitamin or mineral,” according to Elena Philippou, PhD, RD, associate professor of nutrition-dietetics at the University of Nicosia, Nicosia, Cyprus, and Elena Nikiphorou, MBBS, a rheumatologist at King’s College London, London, England. For some patients, deficiency is a reality. A retrospective cohort study in Journal of Clinical Medicine found that people with RA were 17% more likely than age-matched control individuals to have nutrient deficiencies, perhaps because symptoms like fatigue, pain, and nausea affect their eating habits. Here’s what the science says about common vitamin supplements.

Vitamin D. This hormone-like vitamin, which attaches to receptors on immune cells to tamp down inflammation, was the most popular dietary supplement among rheumatology patients in a recent study from the UK. Vitamin D deficiency is common in people with RA, lupus, Sjögren disease, ankylosing spondylitis, systemic sclerosis, and fibromyalgia. In some cases, vitamin D levels track with disease activity, research suggests. Corticosteroids can also make vitamin D deficiency more likely. Can supplements help?

In RA, evidence points to small improvements. A systematic review of 11 studies including 3049 patients published in Nutrition Reviews showed that vitamin D supplements significantly reduced patients’ pain and Disease Activity Score in 28 joints (DAS28) using both C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR).

The research is mixed on the benefits of vitamin D supplementation for fibromyalgia symptoms, according to a study review in SN Comprehensive Clinical Medicine that included two studies and 80 patients on supplementation. However, researchers said it’s still worth discussing the potential benefits of taking vitamin D.

“Vitamin D supplementation is important in the context of various rheumatic diseases to prevent or treat bone disease,” said Philippou and Nikiphorou. “People with rheumatic disease should speak to their healthcare provider and ask to check their blood vitamin D concentration.” The results can help you recommend a dose.

Folate. Patients on methotrexate should take folic acid supplements under the guidance of a healthcare provider, said Philippou and Nikiphorou. The reason: Methotrexate can deplete folic acid levels, increasing the risk for side effects. An analysis of adverse event reports published in the journal Pharmacoepidemiology showed that methotrexate users who took folic acid (or tumor necrosis factor alpha inhibitors) had a reduced risk for hepatotoxicity or myelosuppression. A commonly recommended dose is 1 mg/d.

Vitamin B12. In a 2024 perspective paper in Rheumatology International, researchers said physicians should assess vitamin B12 levels early in the diagnostic process of rheumatologic diseases. One reason: Many symptoms of pernicious anemia, like fatigue, mimic symptoms of rheumatologic diseases. The gastrointestinal (GI) effects of systemic sclerosis could bring on vitamin B12 deficiency. In a small study in Journal of Clinical Rheumatology, 44 of 62 patients with systemic sclerosis had low vitamin B12 levels.

Vitamin E. Vitamin E deficiency is rare in healthy adults. However, some medical conditions, like inflammatory bowel disease and malabsorption disorders, can make vitamin E deficiency more likely. In RA, a vitamin E supplement could help reduce joint swelling and sensitivity, according to a systematic review of nine studies including 39,845 patients in European Journal of Clinical Nutrition. Researchers credit the nutrient’s role in aiding intestinal repair. Use with caution, as this supplement can increase bleeding risk in doses over 1000 mg/d.

Vitamin A. Like vitamin E, vitamin A deficiency is rare in the United States. The risk of over-supplementing is higher than under-supplementing. However, vitamin A deficiency can happen in people with chronic pancreatic, liver, or GI problems. In people with deficiency, a vitamin A supplement can help relieve dry eye symptoms common in Sjögren disease, suggests a narrative review published in Nutrients. Vitamin A might help reduce ocular surface changes by supporting the production of proteins that protect the outermost surfaces of the eyes. The recommended daily allowance for vitamin A is 900 μg. High-dose supplements can cause toxicity, resulting in GI symptoms and problems like lethargy, drowsiness, increased intracranial pressure, and skin changes.

SUBHEAD – The Replacements

These substances are similar to naturally occurring compounds in our bodies. The question is whether ingesting them yields benefits.

Glucosamine and chondroitin. Glucosamine and chondroitin occur naturally in our bodies and help us form and protect connective tissues. In pill form, this combo is the most popular dietary supplement for OA, according to research in the journal Maturitas. But studies of its effectiveness yield mixed results. A systematic review of 25 studies published in Inflammopharmacology showed that in patients with knee OA, supplementation with about 1500 mg of glucosamine per day reduced tibiofemoral joint space narrowing, while supplementation with about 800 mg/d of chondroitin reduced pain intensity and improved physical function compared with placebo. The duo of glucosamine and chondroitin did not bring significant benefits, perhaps because more studies are needed. Most side effects were mild, but some literature points to the potential for glucosamine to increase warfarin’s blood-thinning effects.

Omega-3 fatty acids. Fish oil is a top-selling supplement, and it might be helpful in inflammatory rheumatologic diseases. A systematic review of 30 studies including 710 patients published in Arthritis Research & Therapy showed that omega-3 fatty acid supplements can improve pain, swollen and tender joint count, DAS28 scores, and Health Assessment Questionnaire scores in patients with RA, psoriatic arthritis, or ankylosing spondylitis. In patients with lupus, a study review that included five studies and 284 patients in International Journal of Environmental Research and Public Health suggested omega-3 fatty acid supplements could improve ESR, CRP, disease activity, inflammatory markers, and oxidative stress and improve lipid levels and endothelial function.

Omega-3 fatty acids have anti-inflammatory effects that might explain their benefits. In patients with RA, for example, fish oil supplementation was associated with elevated blood levels of resolvins and protectins, which help quell inflammation, according to a study in Prostaglandins, Leukotrienes and Essential Fatty Acids.

Philippou and Nikiphorou recommended combining food and supplements: Eat oily fish at least twice a week, regularly consume plant-based sources of omega-3s — like chia seeds, flaxseeds, or walnuts — and consider a daily supplement that contains 2 g of omega-3s from docosahexaenoic acid and eicosapentaenoic acid. Most fish oil side effects are mild, like heartburn and bad breath. Fish oil can have blood-thinning effects at high doses, so special attention is needed for patients on anticoagulants.

Probiotics. Building up the good bacteria in your gut might help you fight the effects of rheumatologic diseases. A systematic review of 80 randomized controlled trials in BMC Medicine suggested that therapies targeting the gut microbiota might improve the symptoms or inflammatory factors in celiac disease, lupus, juvenile idiopathic arthritis, psoriasis, Sjögren disease, multiple sclerosis, systemic sclerosis, Crohn’s disease, and ulcerative colitis. Probiotics were also shown to relieve pain in fibromyalgia, but they didn’t affect scores on the Fibromyalgia Impact Questionnaire. Probiotics were not helpful in spondyloarthritis or RA. There were no adverse events. By improving the balance of bacteria in the gut, probiotics might inhibit pro-inflammatory factors and signaling pathways and regulate CD4+ T-cell differentiation, the researchers wrote.

Not all probiotic supplements are created equal. Effects can vary by microorganism and dose. Until more high-quality studies are published, Philippou and Nikiphorou recommend daily consumption of probiotic food sources such as yogurt, kefir, sauerkraut, kimchi, tempeh, miso, and kombucha, along with prebiotic food sources such as bananas, onion, artichokes, asparagus, oats, leeks, and garlic.

Collagen. An increasingly popular supplement for hair, skin, and nails, some collagen peptide or hydrolyzed collagen supplements come with claims about joint health, too. Inside our bodies, collagen helps build joints. As a supplement, the jury is still out. A systematic review of 19 studies in International Journal of Rheumatic Diseases suggested more research is needed to determine whether collagen supplements are harmful or helpful in OA or RA. Studies haven’t shown adverse events, and doses typically range from 2.5 to 15 g/d.

Coenzyme Q10 (CoQ10). This antioxidant occurs naturally in our cells and is produced through microbial fermentation for use in dietary supplements. A study review of 20 articles including 483 patients in Clinical Nutrition ESPEN concluded that CoQ10 supplementation up to 300 mg/d was beneficial in RA, fibromyalgia, or antiphospholipid syndrome (APS).

In RA, CoQ10 supplementation improved disease activity index, ESR, and cytokine levels and decreased malondialdehyde. CoQ10 might protect against the overproduction of reactive oxygen species that can promote inflammation and joint damage, the researchers said. In fibromyalgia, CoQ10 was linked with improvements in pain, fatigue, sleep, tender points count, mood disorders, and scores on the Fibromyalgia Impact Questionnaire in most of the included studies. CoQ10 might help in fibromyalgia by improving mitochondrial dysfunction. In APS, CoQ10 improved endothelial function and decreased prothrombotic and pro-inflammatory mediators. CoQ10 might change the expression of genes that promote atherosclerosis. A few patients had GI side effects like nausea and diarrhea, but the supplements were generally well tolerated.

Melatonin. Commonly touted as a sleep aid, this hormone has immune and anti-inflammatory activities that could benefit people with rheumatologic diseases. A study review of 13 articles including 533 patients in Clinical Nutrition ESPEN concluded that melatonin can help improve sleep, pain, and mood in fibromyalgia, OA, and osteoporosis but not in RA. Side effects were minimal, but a few people experienced nausea, drowsiness, nightmares, or headaches. Doses of 5-6 mg/d are likely safe for most adults.

SUBHEAD – The Plant-Derived Antioxidants

Many supplements used in rheumatology are antioxidants derived from herbs, spices, or other plants. When plants encounter stressors, like temperature changes or hungry insects, their secondary metabolism revs up and creates compounds with biological properties. Some of these substances influence inflammatory pathways in the human body, said Luís Silva, PhD, a medicinal chemistry researcher at the Polytechnic Institute of Guarda, Guarda, Portugal. “If it is possible to reduce these kinds of anti-inflammatory processes, it is also possible that we could help people with inflammatory diseases to a good life, or a better life,” he said.

Turmeric and curcumin. You might see this supplement labeled as turmeric, a golden spice in curry powder, or curcumin, an antioxidant compound known as a curcuminoid in turmeric. Curcuminoids might reduce inflammation by scavenging free radicals and inhibiting enzymes that make prostaglandins, Silva said.

Turmeric is the most popular herbal supplement for people with RA, according to Funk’s research. A study review of six publications including 539 patients in Frontiers in Immunology showed that curcumin supplements improved RA patients’ ESR, DAS, swollen joint count, and tender joint count. Turmeric could help patients with OA, too. Patients with OA who took 1000 mg/d of curcumin improved their pain and function, according to a systematic review including 12 studies and 1438 participants in the journal Nutrients. In lupus, small studies are promising but inconclusive, suggested a study review in Frontiers in Immunology.

Watch patients taking turmeric and methotrexate closely, Funk said. Both have been associated with liver problems. Some users also experience GI symptoms like diarrhea because turmeric doesn’t absorb well in the GI tract, she said.

Milk thistle (silymarin). This flowering plant is often marketed as a liver-supporting supplement, but research also suggests promise in RA and OA. A systematic review of 12 studies in Current Rheumatology Reviews suggested that silymarin supplements might help relieve pain, reduce inflammation, and protect the cartilage matrix, synovial membrane, and cartilage cells in joints. This supplement might help via immunomodulatory, anti-inflammatory, antioxidant, and anti-apoptotic properties, the researchers said. Doses of 250-750 mg appear to be safe. Side effects such as gastroenteritis, diarrhea, bloating, and headache can occur.

Boswellia serrata. Sourced from the resin of a tree that grows in dry, mountainous regions of Asia and Africa, Boswellia serrata can help relieve joint pain and stiffness and improve joint function in OA, suggested a systematic review of seven trials involving 545 patients in BMC Complementary Medicine and Therapies. Users saw benefits when taking 100-250 mg/d for 4 weeks or more. Compounds in Boswellia serrata may inhibit 5-lipoxygenase, an enzyme involved in producing inflammatory leukotrienes. No adverse events were reported. In some studies, users have reported GI side effects.

Ginger. Ginger is a popular herbal supplement among people with RA, Funk’s research suggested. One small clinical trial involving 70 patients with RA in the journal Gene showed that taking 1500 mg/d of ginger for 12 weeks improved their DAS and boosted their expression of FoxP3 genes, which are linked with the function of regulatory T cells. A meta-analysis including three studies with 330 patients taking ginger published in the journal Nutrients suggested ginger can reduce pain and systemic inflammation in people with OA. Preclinical studies suggested phenolic compounds in this spicy root, such as gingerols, reduce inflammation through multiple mechanisms.

Funk’s research revealed wide variation in the quality of ginger supplements, reinforcing the importance of selecting an independently verified product. Research suggested a safe dose is up to 2-2.5 g/kg body weight.

Resveratrol. Found in red grapes and red wine, this compound is particularly good at blocking COX-2 enzymes, an important step in the inflammatory cascade, Silva said. “Because of their chemical structure, they have great affinity to these enzymes to lead to their inhibition,” he said. A study review of five articles including 481 patients in European Journal of Rheumatology showed that people with OA, RA, or Takayasu arteritis who took 250-1000 mg/d of resveratrol saw improvements in pain, function, disease activity, joint swelling, and inflammation, with no side effects.

Cinnamon. This warming spice is gaining popularity as a supplement, reported the American Botanical Council. Cinnamon is often marketed as lowering blood sugar and supporting bone health. In a small study of 36 women with RA published in Journal of the American College of Nutrition, participants who consumed 2 g/d of cinnamon powder had reduced DASs along with reduced pain and tender and swollen joint counts. Cinnamon may reduce pain by inhibiting prostaglandin and blunt inflammation by reducing the release of arachidonic acid from cell membranes, according to a study review in Frontiers in Pharmacology. GI problems and allergic reactions are among the most common side effects.

Funk, Nikiphorou, Philippou, and Silva all had no relevant disclosures.