Ashwagandha Advantages: Evidence-Based Benefits, Risks, and How to Use It

What Is Ashwagandha and How Does It Work?

Ashwagandha (withania somnifera) is an adaptogenic shrub that has been used in ayurvedic medicine for over 3,000 years across India, the Middle East, and parts of Africa. Traditionally classified as a “Rasayana” herb, it was prescribed to promote vitality, resilience, and longevity.

Modern ashwagandha supplements are typically made from standardized root extract, though some products include leaf extracts as well. You’ll often see it marketed as “indian ginseng” or “winter cherry,” though it’s botanically unrelated to true ginseng.

The key bioactive compounds include:

Withanolides (especially withaferin A and withanolide A)

Sitoindosides

Various alkaloids and saponins

These compounds are thought to influence the stress response, reduce inflammation, and modulate hormone signaling throughout the body.

So what exactly is an “adaptogen”? In everyday terms, it’s a plant that appears to help your body balance its response to physical and emotional stress. Ashwagandha does this primarily by modulating the HPA (hypothalamic–pituitary–adrenal) axis—the system that controls cortisol and other stress hormones.

Most modern scientific evidence comes from randomized controlled trials and systematic reviews published through around 2021. While the data is promising, sample sizes have generally been small and study durations short. This means we have good signals but not definitive proof for many claimed advantages.

Advantages for Stress, Anxiety, and Mood

Stress and anxiety relief is the best-supported advantage of ashwagandha in current clinical research. If you’re looking for one reason to consider this herbal supplement ashwagandha, this is it.

Several randomized controlled trials conducted between 2012 and 2021 found that daily ashwagandha extract significantly reduced perceived stress scores and serum cortisol levels compared with a placebo group. In a 2019 placebo controlled study, adults experiencing high stress showed cortisol reductions in the range of 20–30% after 8 weeks of supplementation.

What the Research Shows

Outcome	Typical Improvement	Study Duration
Perceived Stress Scale (PSS)	Significant reduction vs placebo	6–8 weeks
Serum cortisol levels	20–30% decrease	8 weeks
Hamilton Anxiety Rating Scale (HAM-A)	Statistically significant improvements	6–12 weeks

A 2021 systematic review found that doses of approximately 300–600 mg/day of high-concentration root extract (such as KSM-66 or similar standardized ashwagandha products) appear more effective than lower doses for anxiety reduction.

Participants in these trials often reported:

- Reduced feelings of stress and anxiety

- Improved overall well-being

- Better ability to concentrate

- Less irritability and fatigue

However, most trials were short (6–12 weeks) and involved relatively small sample sizes—often under 150 participants. This limits how confidently we can generalize the findings.

The Canadian Network for mood and anxiety treatments has provisionally suggested 300–600 mg/day for generalized anxiety disorder as an alternative medicine approach. But researchers emphasize the need for more large, long-term trials before firm guidelines can be established.

The mechanism appears to involve modulating stress hormones through the HPA axis, along with GABA-mimetic effects that may calm the nervous system without the heavy sedation of benzodiazepines.

Advantages for Sleep Quality and Insomnia

The species name “somnifera” literally means “sleep-inducing”—a reflection of ashwagandha’s traditional use for calming the mind and improving rest. Modern research suggests this traditional wisdom has merit.

Clinical trials have found that standardized ashwagandha root extracts produce small but meaningful improvements in sleep quality compared with placebo. These advantages are most pronounced in people diagnosed with insomnia.

Key Sleep Findings

A 2021 systematic review found more pronounced advantages on sleep when:

- Doses of around 600 mg/day were used

- Supplementation continued for 8 weeks or longer

- Participants had baseline sleep complaints

Studies using branded extracts such as KSM-66 and Shoden reported:

- Better subjective sleep quality scores

- Reduced sleep onset latency (falling asleep faster)

- Improved sleep efficiency (more time asleep vs. time in bed)

- Fewer nighttime awakenings

Individual responses can vary considerably. Some people notice improvements within 2–3 weeks, while others may need the full 8-week period to experience meaningful changes.

Important cautions:

- Do not stop prescribed sleep medications without medical supervision

- Ashwagandha may cause drowsiness and should be used carefully alongside other sedatives

- The calming effect is generally milder than prescription sleep aids

Advantages for Physical Performance, Muscle Strength, and Recovery

The Sanskrit name “ashwagandha” roughly translates to “smell of the horse,” implying the strength and stamina the herb was traditionally believed to confer. Modern research has begun to validate some of these claims, though the evidence remains preliminary.

Strength and Muscle Building

A 2018 randomized placebo controlled trial in resistance-trained men found that approximately 500 mg/day of ashwagandha root extract improved:

- Maximal strength on bench press and squat

- Muscle size (cross-sectional area)

- Reduced exercise-induced muscle damage markers

Participants taking ashwagandha showed statistically significant improvements over the placebo group after 8 weeks of training.

Endurance and Recovery

In several small studies from the mid-2010s, ashwagandha supplementation improved:

- Sprint and cycling time trial performance

- VO₂ max (a measure of aerobic capacity)

- Subjective recovery scores after exercise

- Quality-of-life measures in athletes

One trial using 500 mg aqueous root extract twice daily for 8 weeks showed significant improvements in time to exhaustion compared with placebo.

Testosterone and Hormonal Effects

Some research has found modest increases in testosterone levels in men with low or borderline levels. This may partially explain perceived advantages in strength, energy, or libido. However, effects on testosterone appear inconsistent across studies.

Important limitations:

- Most studies involved young, healthy men

- Sample sizes were small (typically 50–100 participants)

- Study durations were short (8–12 weeks)

- Results may not generalize to women, older adults, or people with chronic illness

Other Potential Advantages (Cognition, Immunity, Metabolic Health)

Beyond stress, sleep, and physical performance, ashwagandha is being studied for many other health benefits. However, the evidence in these areas is currently mixed or preliminary.

Cognitive Function

Small trials suggest possible advantages for:

- Memory and recall

- Attention and focus

- Information-processing speed

One study in 50 adults taking 600 mg/day for 8 weeks showed improvements in immediate and general memory compared with placebo. Research in people with bipolar disorder found better verbal working memory and reaction time with ashwagandha supplementation.

The proposed mechanisms include acetylcholinesterase inhibition (similar to some Alzheimer’s medications) and anti inflammatory properties that may protect neurons.

Immune System Effects

Early findings suggest ashwagandha may influence immune activity by:

- Increasing certain white blood cell counts

- Modulating inflammatory markers

- Enhancing antibody production

This makes it of interest in infection and autoimmune research, but also raises concerns about overstimulating the immune system in certain conditions like rheumatoid arthritis or lupus.

Metabolic Health

Preliminary data suggests ashwagandha might:

- Slightly lower blood sugar and insulin resistance

- Reduce blood pressure modestly

- Improve lipid profiles (cholesterol, triglycerides)

These findings are based on small studies and require larger, well-controlled trials before any recommendations can be made.

What Ashwagandha Is NOT Proven to Treat

There is inadequate scientific evidence to recommend ashwagandha as a treatment for:

- COVID-19 or other infections

- Asthma or respiratory conditions

- Major depression or serious psychiatric disorders

- Cancer (despite promising preclinical data)

Claims of ashwagandha being a “cure-all” are not supported by robust data. While biological psychiatry research is exploring its mechanisms, it remains a dietary supplement, not a proven treatment for serious medical conditions.

Safety, Side Effects, and Who Should Avoid Ashwagandha

Ashwagandha is generally considered “possibly safe” for most healthy adults when taken orally in typical doses for up to about 3 months. However, long term safety is not well studied, and several important adverse effects have been reported.

Common Mild Side Effects

Most side effects are dose-dependent and reversible:

- Upset stomach or nausea

- Loose stools or diarrhea

- Vomiting

- Daytime drowsiness or sedation

- Headache

If these symptoms persist, reduce the dose or discontinue use.

Serious Reported Adverse Events

Liver Injury

Case reports have documented ashwagandha induced liver injury, including:

- Cholestatic hepatitis

- Mixed-pattern liver damage

- Rare cases of severe liver failure

Drug induced hepatocellular injury has occurred within weeks to a few months of starting high-dose or multi-ingredient products. Anyone with chronic liver disease should avoid ashwagandha or use extreme caution under specialist supervision.

Thyroid Effects

Ashwagandha may increase thyroid hormone levels, potentially causing or worsening:

- Hyperthyroid symptoms (rapid heart rate, weight loss, anxiety)

- Problems in people with overactive thyroid

- Interference with thyroid hormone medications

Some studies in subclinical hypothyroid patients showed increased T3 and T4 levels, which could be beneficial for some but dangerous for others.

Who Should Avoid Ashwagandha

Population	Reason for Caution
Pregnant women	Reports of miscarriage and possible uterine-stimulating effects
Breastfeeding women	Safety unknown; not recommended without medical advice
People with autoimmune conditions	May overstimulate the immune system
Those with hormone-sensitive prostate cancer	Potential hormonal effects
People with chronic liver disease	Risk of hepatotoxicity
Patients scheduled for surgery	May affect anesthesia, blood pressure, and bleeding
People with an underactive thyroid on medication	May require dose adjustment

Drug Interactions and When to Talk to a Clinician

Ashwagandha preparations contain multiple active compounds that can interact with prescription and over-the-counter medications. Understanding these interactions is essential before taking ashwagandha supplements.

Thyroid Hormone Medications

Ashwagandha may increase thyroid hormone levels and interfere with:

- Levothyroxine (Synthroid)

- Other thyroid hormone medications

This can potentially cause symptoms like palpitations, weight loss, or worsening anxiety. If you’re on thyroid hormone medications, monitor your thyroid hormone levels closely with your healthcare professional.

Sedatives and CNS Depressants

Ashwagandha can enhance sedative effects when combined with:

- Benzodiazepines (Xanax, Valium, Ativan)

- Prescription sleep medications

- Opioid pain medications

- Alcohol

This increases the risk of excessive drowsiness, confusion, or slowed breathing.

Blood Pressure and Diabetes Medications

Ashwagandha may lower blood pressure and blood sugar, which can be problematic if you take:

- Antihypertensive medications (may lower blood pressure too much)

- Insulin or oral diabetes medications (may cause hypoglycemia)

People with high blood pressure or diabetes should only use ashwagandha under medical supervision with close monitoring.

Immunosuppressants

Because ashwagandha may stimulate immune function, it can counteract drugs designed to suppress immunity:

- Medications for autoimmune disease

- Anti-rejection drugs for organ transplant

- Certain cancer treatments

Before Starting Ashwagandha

Always bring a full list of all medications and supplements to your healthcare provider. Key recommendations:

- Discuss potential interactions before starting

- Stop ashwagandha at least 1–2 weeks before planned surgery

- Report any new symptoms promptly

- Consider a clinical evaluation before and during use if you have complex health conditions

How to Choose and Use Ashwagandha Supplements

Quality and standardization vary widely between brands. Many reported problems with herbal supplements arise from contamination, adulteration, or inaccurate labeling. Choosing wisely can help you maximize potential advantages while minimizing risks.

What to Look For

Standardization

Products should specify withanolide content (typically 2.5–5% or higher)

Look for novel standardized ashwagandha products with defined phytochemical profiles

Extract Type

Root-only extracts are most commonly studied

Some products mix root and leaf; be aware of what you’re getting

Third-Party Testing

Look for certifications from NSF, USP, or ConsumerLab

Independent testing helps verify purity and potency

Reputable Brands

Clinically tested extracts like KSM-66 or Shoden have more research behind them

Avoid products with excessive additional ingredients

Typical Dosing Ranges

Based on modern clinical trials:

Purpose	Dose Range	Duration
Stress and anxiety	300–600 mg/day	6–12 weeks
Sleep quality	300–600 mg/day	8+ weeks
Physical performance	500–1000 mg/day	8–12 weeks

Practical tips:

- Take with food to reduce upset stomach

- Start with the lowest effective dose

- Gradually increase if tolerated

- Watch for side effects (digestive issues, fatigue, mood changes)

Setting Realistic Expectations

Ashwagandha should be viewed as an adjunct, not a replacement, to evidence-based treatments and lifestyle strategies for managing stress, improving sleep, or addressing chronic health conditions.

Encourage a time-limited trial approach:

1. Start supplementation with clear goals in mind

2. Use for 8–12 weeks

3. Reassess with your clinician

4. Decide whether advantages outweigh any side effects before continuing

Western medicine approaches may still be necessary for serious conditions, and herbal medicine like ashwagandha works best as part of a comprehensive health strategy.

FAQs About Ashwagandha Advantages

Can I take ashwagandha every day?

Most clinical trials have used daily dosing for 6–12 weeks and found it generally safe in healthy adults. However, there is little data beyond about 3 months of continuous use. If you plan to use ashwagandha longer term, consider taking periodic breaks (for example, one week off every two months) and check in with a healthcare provider to monitor for any emerging issues.

How long does it take to notice advantages for stress or sleep?

Some participants in placebo controlled trials reported improvements in stress or sleep within 2–4 weeks. However, most randomized controlled trials measured meaningful changes by 6–8 weeks. Individual responses vary considerably based on baseline stress levels, sleep habits, and overall health. Unlike some prescription medications that work immediately, ashwagandha appears to work gradually through its effects on the stress response system.

Is ashwagandha safe for teenagers or older adults?

The bulk of research involves adults between about 18 and 65 years of age. Data in adolescents is extremely limited, and studies specifically in older adults are scarce. Minors, people over 65, and those taking multiple medications should only consider taking ashwagandha under direct medical supervision. The ashwagandha plant’s effects on developing endocrine systems or in polypharmacy situations are not well understood.

Can I combine ashwagandha with other adaptogens like rhodiola or holy basil?

Combinations are common in traditional herbal medicine practices but are not well studied in modern clinical trials. Combining multiple adaptogens may increase both potential advantages and risks. The safest approach is to introduce only one new product at a time, observe your response over several weeks, and discuss any planned combinations with your healthcare professional before adding additional herbs.

Does ashwagandha cause weight gain or weight loss?

Current evidence does not show a consistent effect on body weight from withania somnifera root extract. Some people may indirectly experience weight changes if stress levels, appetite, sleep patterns, or physical activity shift while taking ashwagandha. It should not be viewed as a weight-control supplement. If you’re concerned about weight changes, track your diet and activity levels separately and discuss any significant shifts with your healthcare provider.