Can You Take Ashwagandha and Magnesium Together?

Yes, for most healthy adults. Neither NIH fact sheet lists the other supplement as an interaction^{1, 2}, and in the one trial that paired a multi-ingredient morning ashwagandha blend with a multi-ingredient evening magnesium blend, the morning blend alone scored better on sleep quality³.

Taking both is reasonable but unproven as a combination. The real risks come from ashwagandha (rare liver injury, pregnancy, thyroid and sedative medicines) and from magnesium (kidney disease, some antibiotics and bone drugs)^{1, 2}.

No interaction between the two is documented. NCCIH's ashwagandha fact sheet names medicines for diabetes and high blood pressure, immunosuppressants, sedatives, anticonvulsants and thyroid hormone medicines as possible interactions, and magnesium is not on that list¹. The NIH magnesium fact sheet names oral bisphosphonates, tetracycline and quinolone antibiotics, diuretics and proton pump inhibitors, and ashwagandha is not on that list either².

That is an absence of reports, not a trial result: we found no randomized trial comparing ashwagandha plus magnesium with each alone.

The closest evidence is a 2026 trial in 103 healthy, physically active adults³. They were randomized to a morning blend of 600 mg ashwagandha and 300 mg Rhodiola rosea, an evening blend of 2 g magnesium L-threonate (delivering 145 mg of magnesium), 200 mg L-theanine and 50 mg apigenin, both blends, or placebo, for two weeks³.

• Morning blend alone: lower weekly perceived stress (p = 0.034), fewer sleep-related impairments (p = 0.032) and less time awake after sleep onset (p = 0.047)³.
• Morning blend versus both blends: sleep quality on the Pittsburgh Sleep Quality Index was better with the morning blend alone, by a mean difference of 0.66 points (p < 0.001)³.

Three limits apply. Both blends held other ingredients, so the result cannot be pinned on magnesium. The supplementation lasted two weeks. The authors note that minimal effects on other outcomes may reflect limited benefit in healthy people over a short period³.

Read it as "adding an evening magnesium blend did not help here", not as proof of harm.

The case for taking both comes from separate bodies of evidence. Where reviews graded certainty, they rated it low to very low.

Ashwagandha

• Sleep: a 2021 meta-analysis of 5 randomized trials in 400 adults found a small effect (standardized mean difference -0.59, 95% CI -0.75 to -0.42), larger in people with insomnia, at doses of 600 mg a day or more, and over 8 weeks or longer⁴. An 8-week trial in 80 adults (40 healthy, 40 with insomnia) found shorter sleep onset latency in the insomnia group (p = 0.013)⁵.
• Anxiety and insomnia: a 2024 meta-analysis of 5 trials in 254 patients found lower Hamilton Anxiety scores (mean difference -5.96 points), but heterogeneity was extreme (I² = 98%), so the size of the effect is uncertain⁶. NCCIH calls the evidence on anxiety unclear¹.
• Stress: a meta-analysis of 12 trials in 1,002 adults found lower anxiety (SMD -1.55) and stress (SMD -1.75), with low certainty of evidence⁷.
• Cortisol: a 2025 meta-analysis (7 trials on cortisol, 6 on perceived stress, 488 participants) found cortisol fell by 1.16 µg/dL, but perceived stress did not change significantly⁸.

Pair pages cover the details for ashwagandha for insomnia, ashwagandha for cortisol reduction and ashwagandha for anxiety.

Magnesium

• Insomnia in older adults: a meta-analysis of 3 trials in 151 older adults found sleep onset 17.36 minutes shorter than with placebo (95% CI -27.27 to -7.44); total sleep time rose 16.06 minutes, which was not significant, and the evidence was low to very low quality⁹.
• Poor sleepers: in 155 adults, 250 mg of elemental magnesium as bisglycinate cut Insomnia Severity Index scores by 3.9 points versus 2.3 with placebo at week 4 (p = 0.049; effect size 0.2, described as small)¹⁰.
• Overall: a 2026 review of 12 trials called the evidence inconsistent and low to very low in certainty, and concluded it does not support magnesium as a routine insomnia treatment¹¹. A 2024 review of 15 trials found improved self-reported anxiety in 5 of 7 studies that measured it, and suggested the benefit is most likely in people with low magnesium status¹².

See magnesium for insomnia and magnesium for anxiety for the full trial lists.

They are different kinds of supplement. Magnesium is a mineral the body requires, with Recommended Dietary Allowances of 310 to 420 mg a day for adults from food and supplements combined². Ashwagandha is an herb with no required intake. Glycinate is one form of magnesium, so "ashwagandha versus magnesium glycinate" compares a herb with a mineral.

Neither is clearly better. No trial compared them head to head, and comparing separate trials is unreliable because the populations and outcomes differ. Magnesium is the better-founded choice if your intake is low^{2, 12}. The ashwagandha trials were done in stressed or sleep-disturbed adults, so it fits those groups better^{4, 7}.

For the choice between magnesium forms, see our guides to glycinate versus citrate and threonate versus glycinate.

No trial compared timings, and with no documented interaction there is no reason to separate them for absorption. The trials show three patterns:

• Twice daily: 300 mg of ashwagandha root extract morning and evening for 10 weeks in 60 adults with insomnia and anxiety¹³.
• Once at night: 500 mg of a 2.5% withanolide extract once daily at night for 60 days in 54 adults with mild to moderate stress and anxiety¹⁴.
• Split: ashwagandha in the morning and a magnesium blend in the evening, as in the 103-adult trial above³.

Ashwagandha can cause drowsiness in some people¹. If it makes you sleepy, take it in the evening. If it does not, either time fits the trials. For magnesium timing, see when to take magnesium.

How long to wait: the trials above ran 8 to 10 weeks, and the sleep meta-analysis found larger effects at 8 weeks or longer^{4, 13, 14}.

These are the doses the trials used. For self-use in adults, keep supplemental magnesium at or below the 350 mg limit².

• Ashwagandha: 300 mg of extract twice daily in the 10-week insomnia trial¹³. A dose-response analysis found a benefit for stress at 300 to 600 mg a day⁷.
• Magnesium: 250 mg of elemental magnesium in the bisglycinate trial¹⁰, and, in an older-adult insomnia trial, 500 mg a day for 8 weeks in 46 people (the abstract does not say whether this was elemental)¹⁵. The Tolerable Upper Intake Level for supplemental magnesium is 350 mg a day for adults², so 500 mg is above it and not a self-use dose.

The upper limit applies to elemental magnesium in the product, not the weight of the whole compound, so read the elemental figure on the label². NIH says the typical migraine-prevention dose exceeds the limit, so it should be used only under a health care provider's supervision².

Most of the risk sits with one supplement at a time, not with the pair.

Ashwagandha's documented risks

Liver injury is rare but documented. In a case series of 5 patients, jaundice, nausea, lethargy, itching and abdominal discomfort began 2 to 12 weeks after starting, and liver tests normalized within 1 to 5 months in four of them¹⁶. An Indian series of 8 patients taking single-ingredient products found that 5 had underlying chronic liver disease, and 3 of those developed acute-on-chronic liver failure and died¹⁷.

NCCIH adds that ashwagandha should be avoided during pregnancy and not used while breastfeeding, and is not recommended before surgery or with autoimmune or thyroid disorders. People with hormone-sensitive prostate cancer should avoid it because it may raise testosterone. It may be safe for up to 3 months, and there is not enough information on long-term use¹.

Magnesium's documented risks

• Kidney disease: the risk of magnesium toxicity rises with impaired kidney function because the body removes less of the excess².
• Digestive effects: high supplemental doses can cause diarrhea, nausea and abdominal cramping².
• Timing with drugs: take tetracycline or quinolone antibiotics at least 2 hours before or 4 to 6 hours after magnesium, and oral bisphosphonates at least 2 hours apart².

Children: the trials above enrolled adults. NIH sets much lower supplemental magnesium limits for young children (65 mg a day at ages 1 to 3, 110 mg at ages 4 to 8, 350 mg from age 9), and fatal magnesium toxicity has been reported in a toddler². Ask a pediatric clinician before giving either supplement to a child.

Conditions to discuss first: chronic kidney disease and hypothyroidism. Our guide to what not to take with magnesium covers more interactions.

Use this checklist before starting.

• Healthy adult, no medicines: taking both is reasonable. Add one at a time, a week or two apart, because both can upset the stomach (diarrhea, stomach upset or vomiting from ashwagandha; diarrhea, nausea and cramping from high magnesium doses) and you want to know which is responsible^{1, 2}.
• On thyroid, diabetes, blood pressure, sedative, anticonvulsant or immunosuppressant medicines: ask a prescriber or pharmacist before ashwagandha¹.
• On antibiotics, bisphosphonates, diuretics or acid reducers: keep magnesium apart from antibiotics and bisphosphonates, and ask about magnesium status with long-term diuretics or acid reducers².
• Kidney disease: do not self-supplement magnesium².
• On an antidepressant: ask a pharmacist before adding either supplement, and see SSRIs and supplements.

Related reading: stress management and improved sleep quality.

We searched for trials and reviews of ashwagandha, magnesium and the two combined, then read the PubMed records of 15 journal papers (meta-analyses, randomized trials and liver-injury case series) and two NIH fact sheets, and cited all of them. We prioritized systematic reviews and trials in adults. We found no randomized trial of ashwagandha plus magnesium alone, so the combination rests on two separate bodies of evidence and one mixed-blend trial. Researched on 30 October 2026.

1. National Center for Complementary and Integrative Health. Ashwagandha: Usefulness and Safety. https://www.nccih.nih.gov/health/ashwagandha
2. National Institutes of Health, Office of Dietary Supplements. Magnesium: Fact Sheet for Health Professionals. https://ods.od.nih.gov/factsheets/Magnesium-HealthProfessional/
3. Mastrofini GF, et al. Modulating stress and sleep through a multi-compound dietary supplement: a randomized, double-blind, placebo-controlled trial. J Int Soc Sports Nutr. 2026;23(1):2740227. doi:10.1080/15502783.2026.2740227
4. Cheah KL, et al. Effect of Ashwagandha (Withania somnifera) extract on sleep: A systematic review and meta-analysis. PLoS One. 2021;16(9):e0257843. doi:10.1371/journal.pone.0257843 Our study summary.
5. Langade D, et al. Clinical evaluation of the pharmacological impact of ashwagandha root extract on sleep in healthy volunteers and insomnia patients: A double-blind, randomized, parallel-group, placebo-controlled study. J Ethnopharmacol. 2021;264:113276. doi:10.1016/j.jep.2020.113276 Our study summary.
6. Fatima K, et al. Safety and efficacy of Withania somnifera for anxiety and insomnia: Systematic review and meta-analysis. Hum Psychopharmacol. 2024;39(6):e2911. doi:10.1002/hup.2911 Our study summary.
7. Akhgarjand C, et al. Does Ashwagandha supplementation have a beneficial effect on the management of anxiety and stress? A systematic review and meta-analysis of randomized controlled trials. Phytother Res. 2022;36(11):4115-4124. doi:10.1002/ptr.7598 Our study summary.
8. Albalawi AA. Dual impact of Ashwagandha: Significant cortisol reduction but no effects on perceived stress - A systematic review and meta-analysis. Nutr Health. 2025;31(4):1395-1408. doi:10.1177/02601060251363647 Our study summary.
9. Mah J, et al. Oral magnesium supplementation for insomnia in older adults: a Systematic Review & Meta-Analysis. BMC Complement Med Ther. 2021;21(1):125. doi:10.1186/s12906-021-03297-z Our study summary.
10. Schuster J, et al. Magnesium Bisglycinate Supplementation in Healthy Adults Reporting Poor Sleep: A Randomized, Placebo-Controlled Trial. Nat Sci Sleep. 2025;17:2027-2040. doi:10.2147/NSS.S524348 Our study summary.
11. Lopresti AL, et al. Magnesium Supplementation for Sleep in Adults: A Systematic Review of Randomized Controlled Trials. J Diet Suppl. 2026;23(5):553-581. doi:10.1080/19390211.2026.2719670
12. Rawji A, et al. Examining the Effects of Supplemental Magnesium on Self-Reported Anxiety and Sleep Quality: A Systematic Review. Cureus. 2024;16(4):e59317. doi:10.7759/cureus.59317 Our study summary.
13. Langade D, et al. Efficacy and Safety of Ashwagandha (Withania somnifera) Root Extract in Insomnia and Anxiety: A Double-blind, Randomized, Placebo-controlled Study. Cureus. 2019;11(9):e5797. doi:10.7759/cureus.5797 Our study summary.
14. Majeed M, et al. A standardized Ashwagandha root extract alleviates stress, anxiety, and improves quality of life in healthy adults by modulating stress hormones: Results from a randomized, double-blind, placebo-controlled study. Medicine (Baltimore). 2023;102(41):e35521. doi:10.1097/MD.0000000000035521 Our study summary.
15. Abbasi B, et al. The effect of magnesium supplementation on primary insomnia in elderly: A double-blind placebo-controlled clinical trial. J Res Med Sci. 2012;17(12):1161-9. https://pubmed.ncbi.nlm.nih.gov/23853635/ Our study summary.
16. Björnsson HK, et al. Ashwagandha-induced liver injury: A case series from Iceland and the US Drug-Induced Liver Injury Network. Liver Int. 2020;40(4):825-829. doi:10.1111/liv.14393
17. Philips CA, et al. Ashwagandha-induced liver injury-A case series from India and literature review. Hepatol Commun. 2023;7(10). doi:10.1097/HC9.0000000000000270