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Supplements for Scleroderma: What the Trials Show for Raynaud's, Gut Symptoms and Vitamin D

Supplements don't treat scleroderma (systemic sclerosis); your rheumatologist's medicines do. Probiotics, the best-tested option, left overall gut scores unchanged in two small trials, with less reflux in one (grade C), and fish oil, NAC pills, L-arginine and an antioxidant mix did not help Raynaud's caused by scleroderma or a similar disease (grade C). Take iron only for a tested deficiency, and check antacids and grapefruit with your pharmacist.

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Supplements don't treat scleroderma; your rheumatologist does. Systemic sclerosis, the form of scleroderma that can reach the blood vessels, gut, lungs, heart and kidneys, is lifelong, but its symptoms and complications can usually be managed (NHS). The 2023 European (EULAR) recommendations cover Raynaud's, finger ulcers, lung and kidney problems, skin hardening and the gut, and name immune-suppressing and anti-fibrosis medicines such as mycophenolate, nintedanib, rituximab and tocilizumab for skin and lung disease (Del Galdo 2025). Other treatments include methotrexate, cyclophosphamide, ACE inhibitors for the kidneys, acid-reducing medicines for reflux, and bosentan and sildenafil (MedlinePlus). Keep taking what you are prescribed; this guide covers what supplements add, in adults.

The short version

  • Probiotics for gut symptoms (adults with systemic sclerosis, against placebo): no change in overall gut scores in two trials; in one, reflux was lower at 120 days than in a group that started probiotics halfway through, not against placebo. Grade C, mixed (Low 2019; Marighela 2019).
  • Raynaud's with scleroderma: fish oil helped only Raynaud's without another disease, and NAC pills, L-arginine and an antioxidant mix (given with the gout drug allopurinol) did no better than placebo. Grade C (DiGiacomo 1989; Correa 2014; Herrick 2000).
  • Vitamin D: low levels are common, but no adequate trial shows supplements change the disease. Grade D (Diaconu 2021).
  • Vitamin E gel on finger ulcers (a cream, not pills): faster healing in one small open trial. Grade C (Fiori 2009).
  • Iron only for a measured deficiency: anemia is common, most often from iron deficiency, and often from bleeding in the gut, which needs finding (Gachet 2024).
  • Watch the medicine pairs: magnesium or aluminum antacids and some binders lower mycophenolate levels, and grapefruit raises nifedipine levels (mycophenolate label; nifedipine label).
Option (who, compared with what)What trials foundSize of effectGrade
Probiotics (113 adults with scleroderma in 2 trials, vs placebo)Overall gut scores unchanged; in one, less reflux at 120 days than a group that started probiotics laterSmall, mixedC, mixed
Fish oil (32 people with Raynaud's, vs olive oil)Benefit only in Raynaud's without another diseaseNone with sclerodermaC
NAC pills (42 adults with scleroderma, vs placebo)No change in finger blood flow; attacks eased equallyNoneC
Antioxidant mix plus allopurinol (33 adults with limited scleroderma, vs placebo)No clinical benefitNoneC
Vitamin E gel on ulcers (27 adults, vs usual care, open)Ulcers healed fasterAbout 13 vs 21 weeksC
Oral type I collagen (168 adults with diffuse scleroderma, vs placebo)No change in skin scoreNone overallC

What helps scleroderma most?

Prescribed treatment and specialist checks. Your team picks medicines by which organs are involved and checks your blood pressure and organs regularly; physiotherapy and stretching may help keep muscles supple and loosen tight skin (NHS). For Raynaud's, keep hands and feet warm, don't smoke, and go easy on caffeine, which may trigger attacks; a GP may prescribe nifedipine (NHS Raynaud's). Supplements are, at most, small add-ons, and several interact with scleroderma medicines (see below).

Do probiotics help scleroderma gut symptoms?

Grade C, mixed: small trials, mostly no change. In 73 adults, an 8-week multi-strain probiotic left gut symptom and disability scores no different from placebo (Marighela 2019). In 40 adults, a high-dose multi-strain product did not improve overall gut scores against placebo at 60 days, the main outcome; after everyone took the probiotic for the next 60 days, reflux scores were lower in those who had taken it from the start, a secondary outcome (Low 2019). An earlier uncontrolled pilot reported less bloating after 2 months, with no comparison group (Frech 2011).

The pooled analyses disagree. A 2024 review of 4 trials (176 people) found less reflux and bloating, but one of its trials added a yeast probiotic to an antibiotic and compared it with the antibiotic alone, not with a placebo (Ranjbar 2024). A 2025 review of 4 trials (190 people) judged its certainty low or very low and found no clear change in overall gut scores, quality of life or side effects, though social functioning scored slightly better (Wach 2025).

Bacterial overgrowth in the small intestine (SIBO) affects up to 60% of people with systemic sclerosis and improves with antibiotics. In 40 adults with SIBO, an open trial without placebo cleared it in 55% given the antibiotic metronidazole plus the yeast probiotic Saccharomyces boulardii, 33% given the yeast alone and 25% given metronidazole alone (García-Collinot 2020). Test and treatment belong with your team; see small intestinal bacterial overgrowth.

Does anything help Raynaud's with scleroderma?

Grade C: the supplements tested in scleroderma did no better than placebo.

  • Fish oil: in 32 people with Raynaud's taking fish oil capsules or olive oil daily, cold water no longer triggered an attack in 5 of the 11 on fish oil who had primary Raynaud's (no underlying disease), versus 1 of 9 given olive oil, a difference that was borderline; the authors found no benefit in Raynaud's secondary to another disease such as scleroderma (DiGiacomo 1989).
  • NAC by mouth: in 42 adults with scleroderma, NAC pills for 4 weeks did not change finger blood flow, and attacks eased as much on placebo (Correa 2014). The encouraging NAC study was a 5-day drip into a vein with no comparison group, a different route (Sambo 2001).
  • L-arginine: in a crossover trial in scleroderma, 4 weeks of L-arginine did not change finger blood vessel responses against placebo (Khan 1999).
  • Antioxidants: in 33 adults with limited scleroderma, a mix of selenium, vitamins C and E, beta-carotene and methionine, given with the gout drug allopurinol, gave no clinical benefit over placebo in the first 10 weeks (Herrick 2000).
  • Ginkgo: its three trials were in primary Raynaud's, one excluding scleroderma, and they disagree: attacks fell more than on placebo in one, the same as on placebo in another, and less than on nifedipine in the third (Muir 2002; Bredie 2012; Choi 2009). A PubMed search on 9 November 2026 lists 4 papers on ginkgo and scleroderma, none a trial in people with scleroderma.

A 2009 meta-analysis that pooled 20 randomized trials of alternative therapies for Raynaud's saw no clear benefit from any of the nutritional supplements it covered; most of its trials were small, of poor quality and from before 1990 (Malenfant 2009). Our Raynaud's page shows fish oil as "improves" from the same 1989 trial; that result held only for primary Raynaud's.

Should you take vitamin D for scleroderma?

Grade D for changing the disease: no adequate trial. A 2021 review drawing on 40 studies reported that vitamin D is often low in systemic sclerosis and called the value of supplements controversial (Diaconu 2021). In the one placebo-controlled trial of calcitriol, a prescription form, too few people with systemic sclerosis took part to judge it (Hulshof 2000). If a blood test finds you low, your clinician can correct it, as for anyone. Adults should stay at or under 4,000 IU a day, the upper limit, unless advised otherwise, because too much vitamin D raises blood calcium and can calcify soft tissues (NIH ODS; check my stack).

Does vitamin E help finger ulcers?

Grade C for vitamin E gel, applied to the ulcer. In an open trial, 27 adults with 86 finger ulcers had standard ulcer care with or without vitamin E gel; ulcers healed in about 13 weeks with the gel against about 21 without it (Fiori 2009). The study was small and not blinded, and it doesn't support vitamin E pills: in 33 adults, 3 weeks of high-dose vitamin E capsules did not improve blood flow after cold or a marker of oxidative damage against placebo (Cracowski 2005). Finger ulcers need your team's care.

Iron, anemia and "watermelon stomach"

Take iron only if a test shows you need it, with your clinician. Of 502 people with systemic sclerosis, 100 had anemia, most often from iron deficiency (40%), and in 56% of the 32 whose gut was examined, bleeding was found, usually in the upper gut (Gachet 2024). One cause is gastric antral vascular ectasia (GAVE, "watermelon stomach"), fragile blood vessels in the stomach lining: in a European study it affected about 1% of people with systemic sclerosis, and 82% of them had anemia, often needing transfusion (Ghrénassia 2014). Nearly half of them (45%) needed treatment through an endoscope, so a bleed needs finding, not just topping up with iron. The adult upper limit is 45 mg a day, as more upsets the stomach. Iron tablets have also killed young children, so keep them out of reach (NIH ODS); see the iron guide.

Do nutrition drinks help weight loss in scleroderma?

Grade D: one small uncontrolled study. Gut problems affect over 90% of people with systemic sclerosis, and up to 18% score as high-risk on a malnutrition screening tool (Harrison 2012). In 11 malnourished patients, a high-protein nutrition drink improved nutrition scores and lean tissue from baseline, holding at 12 months, with no comparison group (Wojteczek 2024). Ask for nutrition screening and a dietitian; vitamin D, B12, folate, selenium, zinc and iron are often low (Nguyen 2022). See do oral nutrition supplements help malnutrition?

What we'd skip

  • Oral collagen for skin hardening: in 168 adults with diffuse scleroderma, a daily dose of micrograms of bovine type I collagen did not change skin scores over 12 months; only an after-the-fact subgroup improved (Postlethwaite 2008).
  • Aminobenzoate potassium: in 146 people, it did no better than placebo for skin, and 18 stopped it for side effects against 6 on placebo (Clegg 1994).
  • NAC pills, L-arginine, vitamin E pills or antioxidant blends for Raynaud's, for the reasons above.
  • St John's wort if you take nintedanib, whose label says to avoid it because it lowers nintedanib levels (nintedanib label).

Medicines and supplements: what to watch

  • Mycophenolate: magnesium or aluminum hydroxide antacids lower its levels, so take them at least 2 hours after it; acid-reducing proton pump inhibitors, calcium-free phosphate binders and cholestyramine also lower it (mycophenolate label). Ask your pharmacist before adding any magnesium product.
  • Methotrexate: folic acid or folinic acid is given with it to cut side effects, in the dose your prescriber sets, so avoid adding extra folic acid by yourself (methotrexate label).
  • Nintedanib: besides St John's wort, the label asks you to mention laxatives and supplements that can cause diarrhea, a side effect it warns about (nintedanib label).
  • Calcium-channel blockers for Raynaud's: grapefruit about doubles nifedipine levels, so avoid it (nifedipine label); the amlodipine label reports no effect of grapefruit juice (amlodipine label).
  • Cyclophosphamide: its label asks for plenty of fluid around each dose to protect the urinary tract (cyclophosphamide label).

Safety and interactions

  • Fish oil: across 7 heart trials (81,210 people), omega-3 pills raised the chance of atrial fibrillation, a common heart-rhythm problem, by a quarter, with a bigger rise in trials giving over 1 g a day (Gencer 2021). According to the FDA, supplements supplying no more than 5 g of EPA plus DHA daily are safe (NIH ODS). At high doses fish oil can slow blood clotting, and with warfarin it might raise the INR (a clotting test), though most research found 3 to 6 g a day did not significantly change warfarin's effect (NIH ODS). On any blood thinner, ask your prescriber first; see can I take fish oil with Eliquis?
  • Ginkgo: may raise bleeding risk with warfarin and other blood thinners, and may be unsafe in pregnancy (NCCIH).
  • Probiotics: of 93 published cases of infection linked to probiotics, half involved a Saccharomyces yeast (Costa 2018); on immune-suppressing medicines, ask your rheumatologist first.
  • Pregnancy: scleroderma pregnancies carry more risk of miscarriage, poor fetal growth, preterm birth and high blood pressure (Blagojevic 2020), so plan any pregnancy with your rheumatologist and obstetric team while the disease is stable (NHS). Mycophenolate, methotrexate and cyclophosphamide can harm a baby; the mycophenolate label requires birth control during treatment and for 6 weeks after (mycophenolate label; methotrexate label; cyclophosphamide label). Use any supplement only as advised by your midwife or obstetric team.
  • Breastfeeding? Ask your midwife, doctor or a lactation specialist, who can check what passes into breast milk, and your rheumatologist about your medicines.
  • Children: ask your child's doctor before any supplement.

When to see a doctor

  • Get urgent care for new or worse breathlessness, which can mean lung scarring or high blood pressure in the lungs (MedlinePlus).
  • The same day for a sudden jump in your blood pressure readings or far less urine than usual. Scleroderma renal crisis, very high blood pressure with kidney injury, is life-threatening and treated with ACE inhibitors (Hudson 2021).
  • Promptly for black or tarry stools, vomiting blood, or new tiredness and paleness, which can mean gut bleeding and anemia (Gachet 2024; Ghrénassia 2014).
  • Soon for trouble swallowing or skin that keeps thickening (MedlinePlus), or weight loss you didn't plan, a warning sign of malnutrition (Harrison 2012).

Don't stop a prescribed medicine on your own; ask the prescriber or pharmacist. Under 18? A clinician should advise you first.

FAQ

What supplements help scleroderma? None is a treatment for the disease. Probiotics gave mixed results for gut symptoms (grade C), vitamin E gel sped finger-ulcer healing in one small trial (grade C), and supplements tested for Raynaud's with scleroderma did no better than placebo (grade C). Your rheumatologist's medicines come first.

Does vitamin D help scleroderma? Many people with scleroderma run low, yet no adequate trial shows that supplements alter the disease (grade D). If a blood test finds you low, correct it with your clinician, staying within 4,000 IU a day unless they advise more, because too much raises blood calcium.

Does fish oil help Raynaud's from scleroderma? In the one trial, fish oil helped only primary Raynaud's; people whose Raynaud's came with a disease such as scleroderma did not benefit (grade C). In heart trials, omega-3 pills raised the chance of atrial fibrillation, more so above 1 g a day.

Can I take antacids or magnesium with mycophenolate? Magnesium or aluminum hydroxide antacids lower mycophenolate levels; the label says to take them at least 2 hours after it. Ask your pharmacist before adding any magnesium product.

Sources

  1. Del Galdo F, et al. EULAR recommendations for the treatment of systemic sclerosis: 2023 update. Ann Rheum Dis. 2025. PubMed 39874231 · doi:10.1136/ard-2024-226430
  2. Low AHL, et al. A double-blind randomized placebo-controlled trial of probiotics in systemic sclerosis associated gastrointestinal disease. Semin Arthritis Rheum. 2019. PubMed 31208714 · doi:10.1016/j.semarthrit.2019.05.006
  3. Marighela TF, et al. Effect of probiotics on gastrointestinal symptoms and immune parameters in systemic sclerosis: a randomized placebo-controlled trial. Rheumatology (Oxford). 2019. PubMed 31056685 · doi:10.1093/rheumatology/kez160
  4. DiGiacomo RA, et al. Fish-oil dietary supplementation in patients with Raynaud's phenomenon: a double-blind, controlled, prospective study. Am J Med. 1989. PubMed 2536517 · doi:10.1016/0002-9343(89)90261-1
  5. Correa MJ, et al. [Oral N-acetylcysteine in the treatment of Raynaud's phenomenon secondary to systemic sclerosis: a randomized, double-blind, placebo-controlled clinical trial]. Rev Bras Reumatol. 2014. PubMed 25458027 · doi:10.1016/j.rbr.2014.07.001
  6. Herrick AL, et al. A double-blind placebo-controlled trial of antioxidant therapy in limited cutaneous systemic sclerosis. Clin Exp Rheumatol. 2000. PubMed 10895372
  7. Diaconu AD, et al. Role of Vitamin D in Systemic Sclerosis: A Systematic Literature Review. J Immunol Res. 2021. PubMed 34881335 · doi:10.1155/2021/9782994
  8. Fiori G, et al. Vitamin E gel reduces time of healing of digital ulcers in systemic sclerosis. Clin Exp Rheumatol. 2009. PubMed 19796562
  9. Gachet B, et al. Prevalence, causes, and clinical associations of anemia in patients with systemic sclerosis: A cohort study. J Scleroderma Relat Disord. 2024. PubMed 39493735 · doi:10.1177/23971983241238921
  10. Frech TM, et al. Probiotics for the treatment of systemic sclerosis-associated gastrointestinal bloating/ distention. Clin Exp Rheumatol. 2011. PubMed 21586214
  11. Ranjbar M, et al. Effects of probiotics supplementation in gastrointestinal complications and quality of life of patients with systemic sclerosis: A systematic review. Heliyon. 2024. PubMed 39247342 · doi:10.1016/j.heliyon.2024.e36230
  12. Wach AA, et al. The efficacy of probiotics, prebiotics or synbiotics in scleroderma: A systematic review. Clin Nutr ESPEN. 2025. PubMed 40311922 · doi:10.1016/j.clnesp.2025.04.004
  13. García-Collinot G, et al. Effectiveness of Saccharomyces boulardii and Metronidazole for Small Intestinal Bacterial Overgrowth in Systemic Sclerosis. Dig Dis Sci. 2020. PubMed 31549334 · doi:10.1007/s10620-019-05830-0
  14. Sambo P, et al. Intravenous N-acetylcysteine for treatment of Raynaud's phenomenon secondary to systemic sclerosis: a pilot study. J Rheumatol. 2001. PubMed 11669166
  15. Khan F, et al. Skin blood flow in patients with systemic sclerosis and Raynaud's phenomenon: effects of oral L-arginine supplementation. J Rheumatol. 1999. PubMed 10555898
  16. Muir AH, et al. The use of Ginkgo biloba in Raynaud's disease: a double-blind placebo-controlled trial. Vasc Med. 2002. PubMed 12710841 · doi:10.1191/1358863x02vm455oa
  17. Bredie SJ, et al. No significant effect of ginkgo biloba special extract EGb 761 in the treatment of primary Raynaud phenomenon: a randomized controlled trial. J Cardiovasc Pharmacol. 2012. PubMed 22030896 · doi:10.1097/FJC.0b013e31823c0bed
  18. Choi WS, et al. To compare the efficacy and safety of nifedipine sustained release with Ginkgo biloba extract to treat patients with primary Raynaud's phenomenon in South Korea; Korean Raynaud study (KOARA study). Clin Rheumatol. 2009. PubMed 19159999 · doi:10.1007/s10067-008-1084-9
  19. Malenfant D, et al. The efficacy of complementary and alternative medicine in the treatment of Raynaud's phenomenon: a literature review and meta-analysis. Rheumatology (Oxford). 2009. PubMed 19433434 · doi:10.1093/rheumatology/kep039
  20. Hulshof MM, et al. Double-blind, placebo-controlled study of oral calcitriol for the treatment of localized and systemic scleroderma. J Am Acad Dermatol. 2000. PubMed 11100017 · doi:10.1067/mjd.2000.108369
  21. Cracowski JL, et al. Effects of short-term treatment with vitamin E in systemic sclerosis: a double blind, randomized, controlled clinical trial of efficacy based on urinary isoprostane measurement. Free Radic Biol Med. 2005. PubMed 15589377 · doi:10.1016/j.freeradbiomed.2004.09.032
  22. Ghrénassia E, et al. Prevalence, correlates and outcomes of gastric antral vascular ectasia in systemic sclerosis: a EUSTAR case-control study. J Rheumatol. 2014. PubMed 24293584 · doi:10.3899/jrheum.130386
  23. Harrison E, et al. Malnutrition in systemic sclerosis. Rheumatology (Oxford). 2012. PubMed 22850183 · doi:10.1093/rheumatology/kes160
  24. Wojteczek A, et al. High-Protein Nutritional Supplements Improve Nutritional Status in Malnourished Patients with Systemic Sclerosis. Nutrients. 2024. PubMed 39203760 · doi:10.3390/nu16162622
  25. Nguyen AD, et al. Micronutrient Deficiencies in Systemic Sclerosis: A Scoping Review. Open Access Rheumatol. 2022. PubMed 36571105 · doi:10.2147/OARRR.S354736
  26. Postlethwaite AE, et al. A multicenter, randomized, double-blind, placebo-controlled trial of oral type I collagen treatment in patients with diffuse cutaneous systemic sclerosis: I. oral type I collagen does not improve skin in all patients, but may improve skin in late-phase disease. Arthritis Rheum. 2008. PubMed 18512816 · doi:10.1002/art.23501
  27. Clegg DO, et al. Comparison of aminobenzoate potassium and placebo in the treatment of scleroderma. J Rheumatol. 1994. PubMed 8151563
  28. Gencer B, et al. Effect of Long-Term Marine ɷ-3 Fatty Acids Supplementation on the Risk of Atrial Fibrillation in Randomized Controlled Trials of Cardiovascular Outcomes: A Systematic Review and Meta-Analysis. Circulation. 2021. PubMed 34612056 · doi:10.1161/CIRCULATIONAHA.121.055654
  29. Costa RL, et al. Infectious complications following probiotic ingestion: a potentially underestimated problem? A systematic review of reports and case series. BMC Complement Altern Med. 2018. PubMed 30541524 · doi:10.1186/s12906-018-2394-3
  30. Blagojevic J, et al. Pregnancy in Systemic Sclerosis: Results of a Systematic Review and Metaanalysis. J Rheumatol. 2020. PubMed 31474594 · doi:10.3899/jrheum.181460
  31. Hudson M, et al. Scleroderma renal crisis. Presse Med. 2021. PubMed 33548376 · doi:10.1016/j.lpm.2021.104063