Ashwagandha vs. Melatonin for Sleep: New Study Finds the Combination Works Best

Getting enough quality sleep isn't just about feeling rested.

Sleep plays a vital role in muscle recovery, immune function, hormone regulation, mental performance, and overall health. Yet millions of adults struggle to fall asleep, stay asleep, or wake up feeling refreshed.

Two of the most popular natural sleep supplements are melatonin and ashwagandha.

Melatonin is well known for helping regulate the body's internal clock, while ashwagandha has gained popularity for its ability to reduce stress and promote relaxation.

But which one works better?

A new randomized, double-blind, placebo-controlled clinical trial set out to answer that question by comparing ashwagandha alone, melatonin alone, their combination, and a placebo in 200 adults with sleep disturbances.

The results were impressive.

While both supplements improved sleep compared with placebo, the combination of ashwagandha and melatonin consistently produced the greatest improvements in sleep quality, sleep duration, sleep efficiency, anxiety, and morning alertness.

Let's take a closer look at what this study found and what it means if you're looking for better sleep.

Why Sleep Matters

Sleep is one of the most powerful recovery tools your body has.

During sleep your body:

• Repairs muscle tissue
• Consolidates memories
• Supports immune function
• Regulates hormones
• Restores mental energy
• Helps regulate appetite and metabolism

Unfortunately, sleep disturbances are increasingly common.

Difficulty falling asleep, frequent nighttime awakenings, and poor sleep quality can affect everything from athletic performance to mood and long-term health.

Ashwagandha and Melatonin Work Differently

Although both supplements are commonly used for sleep, they work through different mechanisms.

Melatonin

Melatonin is a hormone naturally produced by the pineal gland in response to darkness.

Rather than acting as a sedative, melatonin helps regulate your circadian rhythm, signaling to your brain that it's time to sleep.

It's particularly helpful for people who have difficulty falling asleep or whose sleep schedule has been disrupted.

Ashwagandha

Ashwagandha (Withania somnifera) is an adaptogenic herb that has traditionally been used to help the body better cope with stress.

Instead of directly inducing sleep, ashwagandha may improve sleep indirectly by helping reduce stress and anxiety, two of the most common contributors to insomnia.

Because these supplements target different pathways, researchers wondered whether combining them could produce greater improvements than using either one alone.

The Study

Researchers recruited 200 adults between the ages of 18 and 50 who met the DSM-5 criteria for sleep disturbances.

Participants reported:

• Difficulty falling asleep
• Sleeping 6.5 hours or less per night
• Daytime symptoms related to poor sleep

The participants were randomly assigned to one of four groups:

• Placebo
• Ashwagandha only
• Melatonin only
• Ashwagandha plus melatonin

The study lasted eight weeks, and neither the participants nor the researchers knew who received which treatment until the study ended.

The Dosages Used

Researchers used clinically relevant doses of both supplements.

Ashwagandha

• 300 mg of KSM-66® Ashwagandha root extract
• Taken twice daily
• Total daily dose: 600 mg

Melatonin

• 3 mg
• Taken once daily after dinner

The combination group received both supplements for the full eight-week study.

How Sleep Was Measured

One of the strengths of this study is that researchers didn't rely only on participants' opinions.

They evaluated sleep using both objective and subjective measurements.

Objective assessments included:

• Sleep onset latency (how long it took to fall asleep)
• Total sleep time
• Wake after sleep onset
• Sleep efficiency

Researchers also measured:

• Pittsburgh Sleep Quality Index (PSQI)
• Hamilton Anxiety Rating Scale (HAM-A)
• Morning Alertness Rating Scale (MARS)
• Daily sleep diaries

Using multiple assessment tools gives researchers a much more complete picture of how well the treatments worked.

What Did Researchers Find?

The results were remarkably consistent.

Compared with placebo, all three active treatment groups showed improvements in sleep.

However, the combination of ashwagandha and melatonin consistently outperformed either supplement used alone.

Participants taking both supplements experienced the greatest improvements in:

• Sleep onset latency (falling asleep faster)
• Total sleep time
• Sleep efficiency
• Overall sleep quality
• Morning alertness
• Anxiety scores

These improvements were observed using both objective measurements (actigraphy) and validated sleep questionnaires, strengthening confidence in the findings.

Why Might the Combination Work Better?

One of the most interesting aspects of this study is that the two supplements work through different biological pathways.

Melatonin Helps Set the Clock

Melatonin is often called the body's "sleep hormone."

As darkness falls, your brain naturally releases melatonin to signal that it's time to sleep. Supplementing with melatonin can help reinforce this signal, particularly for people who have difficulty falling asleep or whose sleep schedule has been disrupted.

Ashwagandha Helps Quiet the Mind

Ashwagandha doesn't tell your body when to sleep.

Instead, research suggests it may help reduce stress and anxiety while promoting relaxation.

For many people, racing thoughts and elevated stress—not a lack of melatonin—are what keep them awake at night.

Two Different Mechanisms, One Better Outcome

Because melatonin targets your circadian rhythm while ashwagandha targets stress and anxiety, combining the two may address multiple causes of poor sleep at the same time.

That likely explains why the combination therapy produced the greatest improvements across nearly every sleep outcome measured in the study.

Anxiety Improved Too

Sleep and anxiety often go hand in hand.

Poor sleep can increase anxiety, while anxiety frequently makes it harder to fall asleep.

Researchers measured anxiety using the Hamilton Anxiety Rating Scale (HAM-A) and found that participants taking the combination of ashwagandha and melatonin experienced larger reductions in anxiety than those taking either supplement alone.

While the study wasn't designed specifically as an anxiety trial, these findings suggest that reducing stress may have contributed to the improvements in sleep.

Morning Alertness Also Improved

One concern many people have about sleep supplements is waking up groggy.

To evaluate this, researchers measured Mental Alertness on Rising (MARS) each morning.

Interestingly, participants taking the combination therapy reported better morning alertness despite sleeping longer and more efficiently.

This suggests the improvements weren't simply due to sedation but rather to better overall sleep quality.

Were There Any Side Effects?

Safety is always an important consideration when evaluating supplements.

The researchers reported that:

• Both ashwagandha and melatonin were well tolerated
• Only mild adverse events occurred during the study
• No major safety concerns were identified over the eight-week intervention

While these results are reassuring, supplements can still interact with medications or may not be appropriate for everyone. It's always a good idea to discuss new supplements with your healthcare provider, especially if you're pregnant, have a medical condition, or take prescription medications.

Important Limitations

Although this was a well-designed clinical trial, it's important to keep the findings in perspective.

The study included:

• Adults aged 18 to 50 years
• Participants with sleep disturbances
• An eight-week intervention period

It did not include:

• Older adults
• Shift workers
• People with sleep apnea
• Individuals with significant psychiatric disorders
• Long-term follow-up beyond eight weeks

That means we can't assume the same results would apply to every population.

Additional studies with longer follow-up and more diverse participants are still needed.

Which Supplement Should You Choose?

The answer depends on why you're having trouble sleeping.

Melatonin May Be Best If You:

• Have trouble falling asleep
• Experience jet lag
• Work irregular hours
• Need help resetting your sleep schedule

Ashwagandha May Be Helpful If You:

• Feel stressed or anxious at bedtime
• Have trouble relaxing before sleep
• Wake up feeling mentally drained

Consider Both If:

Your sleep problems appear to be related to both stress and difficulty falling asleep.

This study suggests that combining ashwagandha with melatonin may provide greater improvements than either supplement alone, though more long-term research is needed before making broad recommendations.

The Bottom Line

This high-quality randomized clinical trial provides encouraging evidence that both ashwagandha and melatonin can improve sleep in adults experiencing sleep disturbances.

However, the biggest finding was that combining the two supplements consistently produced the greatest improvements in:

• Falling asleep faster
• Sleeping longer
• Better sleep efficiency
• Higher overall sleep quality
• Reduced anxiety
• Better morning alertness

These findings make sense because the two supplements target different aspects of sleep, melatonin helps regulate the body's sleep-wake cycle, while ashwagandha may help reduce stress and promote relaxation.

Although more long-term research is needed, this study suggests that combining these supplements may be a promising option for adults whose sleep difficulties are influenced by both circadian rhythm and stress.

Simply Good Tip

Supplements can support better sleep, but they're most effective when paired with healthy sleep habits.

Try to keep a consistent bedtime, avoid caffeine late in the day, reduce screen exposure before bed, and make your bedroom cool, dark, and quiet. If you're considering melatonin or ashwagandha, choose high-quality products and use them as part of an overall sleep routine—not as a substitute for healthy habits.

References

1. Efficacy and Safety of Ashwagandha Root Extract, Melatonin, and Their Combination in Adults with Sleep Disturbances: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial. Clocks & Sleep. 2026.
2. 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, placebo-controlled study. Journal of Ethnopharmacology. (Referenced within the study.)
3. Xu H, et al. Efficacy of melatonin for sleep disturbance in middle-aged primary insomnia: A double-blind, randomized clinical trial. Sleep Medicine. (Referenced within the study.)
4. Buysse DJ, et al. The Pittsburgh Sleep Quality Index: A New Instrument for Psychiatric Practice and Research. (Referenced within the study.)

FAQ

Is it safe to take ashwagandha and melatonin together?

In this eight-week clinical trial, the combination of 600 mg of KSM-66® ashwagandha daily and 3 mg of melatonin nightly was well tolerated, with only mild adverse events reported. However, you should consult your healthcare provider before combining supplements, particularly if you take medications or have underlying health conditions.

Is ashwagandha or melatonin better for sleep?

Both supplements improved sleep compared with placebo, but the combination of ashwagandha and melatonin produced the greatest overall improvements in sleep onset, sleep duration, sleep efficiency, sleep quality, anxiety, and morning alertness in this study.

How much ashwagandha and melatonin did researchers use?

Participants in the combination group took 300 mg of KSM-66® ashwagandha twice daily (600 mg/day total) along with 3 mg of melatonin once daily after dinner for eight weeks.

Can these supplements replace good sleep habits?

No. While the study found meaningful improvements with supplementation, healthy sleep habits—such as maintaining a regular sleep schedule, limiting evening screen time, and creating a comfortable sleep environment—remain the foundation of good sleep. Supplements are best viewed as an addition to, not a replacement for, those habits.