Life Extension Magazine logo 2023

Experts recommend that adults get seven or more hours of sleep each night

Nearly a third of U.S. adults get less sleep than they should.

Those who rely on medications confront tolerance whereby even higher doses fail to enable restorative sleep.

In an effort to improve sleep without drugs, researchers conducted randomized clinical trials on plant-derived extracts used in traditional medicine.

One of these extracts improved sleep efficiency by 74%, while another enhanced restorative sleep measures by 72%.

This article describes findings from placebo-controlled studies in sleep-challenged humans.

Sleep Deprivation and Human Longevity

Experts recommend that adults get seven or more hours of sleep each night.

Yet around 40% of elderly adults suffer from some form of sleep problem.

For every one-hour reduction in sleep per night, there’s about a 6% increase in risk of death from any cause.

Effects of Plant Extracts

Sleep Deprivation and Human Longevity

Two extracts have been individually tested in randomized placebo-controlled clinical trials, to promote deep, restorative sleep.

1) Black cumin is an herb long used in Indian and Arab traditional medicine. Its health properties come from the seed oil, which contains the active compound thymoquinone.

Scientists developed a black cumin seed extract standardized to 5% thymoquinone, higher than other cumin extracts.

In a small pilot study of healthy subjects with sleep disturbances, it improved sleep quality and duration, and relieved stress and anxiety. This result was confirmed in a larger trial in healthy people with self-reported unsatisfactory sleep (discussed later).

2) Ashwagandha is an herb used for thousands of years in traditional Indian medicine that has been shown to have anxiety-reducing effects. Its roots and leaves contain active compounds called withanolide glycosides.

One clinical trial showed that an extract standardized to 35% withanolide glycosides lowered the stress hormone cortisol, which can help promote sleep.

Clinical Trials with Black Cumin

black cumin extract nightly before bedtime

A study published in 2023 enlisted healthy volunteers who reported non-refreshing sleep. This included waking multiple times nightly or being unable to achieve sound sleep.

Participants were given a placebo or 200 mg of black cumin extract nightly, 20-30 minutes before bedtime. All subjects refrained from caffeine, alcohol, and tobacco.

Beneficial effects were reported by 62% of the black cumin group after a single dose. This rose to an astonishing 88% on day 90.

After 90 days, compared to placebo, the black cumin users were evaluated using a validated self-reported sleep questionnaire. They reported not only better, longer sleep but also improved functioning during the day. Researchers reported improvements of sleep parameters:

  • 74% in sleep efficiency (time asleep out of total time in bed),
  • 56% in sleep latency (time needed to fall asleep after going to bed),
  • 49% in sleep quality,
  • 45% in daytime function,
  • 22% in sleep disturbance, and
  • 20% in sleep duration.

Unlike those using prescription sleep meds, these people performed better the next day without drowsiness.

In a second trial, subjects with non-refreshing sleep took a placebo or 200 mg of black cumin extract nightly, 10-30 minutes before bedtime.

All participants wore an actigraphy wristwatch sensor that monitors rest/activity, a validated objective evaluation of sleep quality and duration.

After just seven days, extract users had meaningfully improved their sleep duration, efficiency, and time to fall asleep, as evaluated by the objective actigraphy sensor. Compared to the placebo, researchers reported improvements of sleep parameters:

  • 69% in restorative sleep,
  • 35% in sleep latency, (amount of time to fall asleep),
  • 23% in time spent awake after sleep onset, (wakefulness time after defined sleep onset),
  • 19% in total sleep time, (from an average 6.4 hours to >7-hour sleep, as recommended by the CDC), and
  • 8% in sleep efficiency (time asleep out of total time in bed).

Compared to the baseline there was 75% improvement in restorative sleep in the group that received the extract. This specific black cumin seed extract, standardized to 5% thymoquinone, safely promotes deeper, more healthful sleep.


Get Deep, Stress-Free Sleep

insufficient or poor-quality sleep

  • Over a third of Americans get insufficient or poor-quality sleep. This increases the risk of many chronic diseases, including heart disease, dementia, and some cancers, and of all-cause mortality.
  • Clinical studies show that two plant extracts safely promote high-quality sleep and reduce stress and anxietywithout compromising daytime functioning.
  • black cumin seed extract improved sleep efficiency by 74% and reduced the time needed to fall asleep by 56%.
  • An ashwagandha extract improved restorative sleep by 72%, reduced stress by 62%, and lowered levels of cortisol (the “stress hormone”) by 67%.
  • Together, these extracts offer a melatonin-free choice for those seeking stress relief and a deeper, more restorative sleep.

Clinical Trials with standardized Ashwagandha

Clinical Trials with standardized Ashwagandha

To test an ashwagandha extract standardized to 35% withanolide glycosides, scientists enlisted 150 volunteers suffering from non-restorative sleep. Half the subjects took a placebo and half took 120 mg of ashwagandha each night for six weeks.

All participants wore an actigraphy wristwatch that monitors rest/activity and evaluates sleep duration, efficiency, and latency.

Those taking ashwagandha had improvements of:

  • 72% in restorative sleep,
  • 27% in sleep latency,
  • 15% in time spent awake after sleep onset,
  • 5% in total sleep time, and
  • 5% in sleep efficiency.

A second clinical study enlisted volunteers with moderate anxiety and elevated cortisol, which can lead to sleep issues. Participants were randomized to receive either ashwagandha 60 mg or 120 mg, or a placebo. They were evaluated at baseline and after 15, 30, 45 and 60 days.

After 60 days, those taking 120 mg of ashwagandha had:

  • 67% reduced cortisol levels,
  • 59% reduced anxiety, and
  • 62% reduced stress.

Standardized to 35% withanolide glycosides, this novel ashwagandha extract safely lowered anxiety and promoted more restful sleep.

Black cumin and ashwagandha extracts have been shown to improve parameters of restorative sleep.


Many Americans turn to medications to cope with poor sleep, but they come with side effects.

Two plant extracts have been shown to improve sleep onset, efficiency, and total sleep time, and reduce anxiety without compromising daytime function.

In clinical studies, a black cumin seed extract improved sleep efficiency by 74% and perceived stress by 44% – leading to improved daytime functioning.

An ashwagandha extract improved restorative sleep by 72% and lowered stress by 62%.

These plant extracts provide an opportunity for more Americans to achieve healthy restorative sleep.

If you have any questions on the scientific content of this article, please call a Life Extension® Wellness Specialist at 1-866-864-3027.

melatonin support for sustained, restful sleep

Recent Issues

life extension magazine july 2024 issue

July 2024

How Aged Black Garlic
Protects the Heart

Read Issue

life extension magazine june 2024 issue

June 2024

Soothe Lower
Back Pain

Read Issue

life extension magazine may 2024 issue

May 2024

Three Nutrients for
Healthy Aging

Read Issue

life extension health magazine april 2024 issue

April 2024

Protect Your Eyes
Against Vision Loss

Read Issue

life extension magazine march 2024 issue

March 2024

Optimize the
Benefits of Broccoli

Read Issue

life extension magazine february 2024 issue

February 2024

Reconnect Aging
Brain Cells

Read Issue

life extension magazine januuary 2024 issue

January 2024

Deliver More
Quercetin to Your Cells

Read Issue

life extension magazine december 2023 issue

December 2023

Sleep Deprivation
and Human Longevity

Read Issue

life extension magazine november 2023 issue

November 2023

Protect Your
Canine Companion

Read Issue