Zinc and ashwagandha: what the evidence says about taking them together

Nobody has tested zinc and ashwagandha together in a trial. What's known about each comes from separate studies, in different people, measuring different outcomes — zinc's trial data covers cold-lozenge duration and testosterone in men who started with low zinc status, ashwagandha's covers perceived stress and cortisol. Combining them is untested, not a proven combination.

What the evidence doesn't support

It doesn't support a claim that zinc and ashwagandha do more together than either does alone — that comparison has never been run. It doesn't support either ingredient as a treatment for a stress condition, and it doesn't support zinc as a treatment for low testosterone in a man whose zinc status is already normal. It also doesn't support assuming ashwagandha's stress-trial doses tell you anything about what a typical zinc serving would add, since the two ingredients have entirely separate literatures.

What the trials found

Ashwagandha's evidence for stress is the more consistent of the two ingredients on this page. A 2012 randomized, double-blind, placebo-controlled trial gave 64 adults with a history of chronic stress 600 mg/day of a concentrated ashwagandha root extract for 60 days; the treatment group had significantly lower stress-scale scores and lower serum cortisol than placebo by day 60. A 2024 meta-analysis pooling nine randomized trials (558 people) found ashwagandha outperformed placebo on the Perceived Stress Scale and on serum cortisol, with doses varying across the nine included trials.

Zinc's evidence runs in a different direction entirely. A 2013 Cochrane review of 16 trials (1,387 people) found zinc lozenges, started within 24 hours of a cold, shortened its length by about a day at doses of 75 mg or more per day. On testosterone, a small 1996 study found that restricting dietary zinc lowered testosterone in young men, and zinc supplementation raised testosterone in elderly men who started with low zinc status — a result that hasn't been shown in men whose zinc status is already normal. Neither of zinc's trials measured stress, mood or cortisol, and neither of ashwagandha's trials measured cold symptoms or testosterone.

No trial has measured the two given together, so there's no dose-matched evidence for a combined product, whatever each ingredient's separate literature suggests on its own. Products that pair zinc with ashwagandha are usually built around a general "vitality" or "recovery" positioning rather than a tested endpoint that covers both.

Ingredient	Best evidence	Population	Dose in that trial
Ashwagandha	Lower stress-scale scores and cortisol vs placebo (2012 RCT, n=64; 2024 meta-analysis of 9 trials, n=558)	Adults with chronic stress	600 mg/day, 60 days (2012 RCT)
Zinc	Colds ~1 day shorter (Cochrane review); testosterone rose in low-zinc-status men only (small 1996 study)	Adults with a cold; men with low zinc status	75+ mg/day lozenges; ~30 mg/day elemental for testosterone
Both together	No trial exists	—	—

Questions people ask

Can you take zinc and ashwagandha together?

There's no trial of the combination, so there's no evidence describing what taking them together does that either doesn't already on its own. Whether it's fine to combine them is a separate safety question, worth raising with a doctor or pharmacist given any medications or conditions involved.

Does ashwagandha work better with zinc?

That specific comparison hasn't been tested. Ashwagandha's own trials, described above, didn't include a zinc arm or a combination arm.

Is zinc and ashwagandha good for testosterone?

Zinc's testosterone data is a small 1996 study limited to men who started with low zinc status. No ashwagandha trial identified for this page measured testosterone as an outcome, and no trial tested the combination for it.

How much zinc and ashwagandha should I take together?

There's no studied combined dose. The 600 mg/day ashwagandha figure above comes from trials that didn't include zinc, and zinc's own trials didn't include ashwagandha, so neither number was established with the other ingredient present.

When to talk to a doctor

Persistent stress or symptoms that might suggest low testosterone are worth bringing to a doctor. Neither zinc nor ashwagandha is a treatment for a stress condition or low testosterone, and nothing in the evidence above supports using either, alone or combined, as a substitute for medical evaluation. Ashwagandha should be discussed with a doctor if you're pregnant or nursing, have a thyroid condition, or take other medication.

Related reading: zinc vs ashwagandha: what the research does and doesn't show, zinc benefits: what the research does and doesn't show, and does zinc help with depression?.