12 supplements for stress and fatigue: effective forms, dosages, and scientific research
Not just ashwagandha: what is the difference between L-theanine, saffron, rhodiola, glycine, and other supplements? When are their effects most relevant, which forms have been studied, and what results have actually been recorded?
Updated October 2026 · Informational content
How to choose based on your needs?
| Need | Most relevant candidates | What to expect |
|---|---|---|
| Long-term tension | Ashwagandha, saffron | Changes in indicators of stress or emotional well-being over several weeks |
| Mental tension | L-theanine, lemon balm | Subjective calmness, changes in certain cognitive indicators |
| Mental fatigue | Rhodiola, bacopa | Indicators of fatigue or cognitive function, depending on the study |
| Poor sleep | Glycine, magnesium (if deficient) | Morning freshness and sleep quality |
| Athletic training load | Phosphatidylserine | Change in cortisol response to exertion in a small study |
| Stress and digestion | Specific psychobiotics | Strain-specific psychological and digestive indicators |
12 supplements: forms, dosages, and results
1. Ashwagandha
When relevant: Prolonged tension, sleep difficulties.
Form: Standardized root or root and leaf extract; check the vitanolide content.
Dosage/duration used in research: 125–600 mg/day, 30–90 days.
What to watch out for: Avoid during pregnancy and breastfeeding; use caution regarding liver, thyroid, and drug interactions.
2. Rhodiola (Rhodiola rosea)
When relevant: Mental fatigue, heavy workload.
Form: Standardized root extract; check the declaration of rosavins and salidroside.
Dosage/duration used in research: 200–400 mg/day in common studies.
What to watch out for: May be stimulating; use caution when taking psychotropic medications.
3. L-theanine
When relevant: Situational mental tension, focus, and sleep quality.
Form: Pure L-theanine (not general green tea extract).
Dosage/duration used in research: 200 mg/day, 4 weeks.
What to watch out for: Potential drowsiness, individual reactions.
4. Phosphatidylserine
When relevant: Response to intense physical exercise.
Form: Phosphatidylserine (PS); distinguish from mixtures of PS and phosphatidic acid.
Dosage/duration used in research: 600 mg/day, 10 days in a small study.
What to watch out for: There is no basis for constantly suppressing a normal physiological response to exercise.
5. Magnesium
When relevant: Low magnesium intake, muscle tension, sleep difficulties.
Form: Bisglycinate or citrate; assess the elemental magnesium content.
Dosage/duration used in research: 100–300 mg of elemental magnesium/day – a practical range, not a proven cortisol dosage.
What to watch out for: In cases of kidney disease or when taking certain antibiotics, safety must be evaluated; higher doses may have a laxative effect.
6. Omega-3 (EPA and DHA)
When relevant: Low consumption of oily fish, general recovery.
Form: Fish or algae oil, with clearly indicated EPA and DHA content.
Dosage/duration used in research: Studies often use 1–2.5 g of EPA+DHA/day.
What to watch out for: Discuss higher doses and use with anticoagulants with a specialist.
7. Saffron extract
When relevant: Emotional tension, low mood.
Form: Standardized Crocus sativus stigma extract, e.g., the studied affron®.
Dosage/duration used in research: 28 mg/day, 4–12 weeks.
What to watch out for: Not a substitute for depression treatment; use caution with concentrated extracts during pregnancy.
8. Glycine
When relevant: Poor sleep and morning fatigue.
Form: Pure glycine powder.
Dosage/duration used in research: 3 g before sleep in a small study.
What to watch out for: May cause digestive discomfort; effects are not the same for everyone.
9. Lemon balm (Melissa officinalis)
When relevant: Short-term tension and relaxation.
Form: Standardized lemon balm leaf extract.
Dosage/duration used in research: 300–600 mg single dose in laboratory studies.
What to watch out for: Potential drowsiness; mg of extract are not equal to mg of dried leaves.
10. Specific psychobiotics
When relevant: Stress accompanied by digestive discomfort.
Form: L. helveticus R0052 + B. longum R0175 – precise strain codes are essential.
Dosage/duration used in research: A specific formula was studied for 30 days; dosage depends on the product.
What to watch out for: Discuss probiotic use with a doctor in cases of immunosuppression or serious illness.
11. Magnolia and Phellodendron extract complex
When relevant: Subjective stress and tension.
Form: Standardized magnolia and Phellodendron complex, e.g., Relora®.
Dosage/duration used in research: 500 mg/day in a small study.
What to watch out for: Potential sedative effect; limited long-term usage data.
12. Bacopa (Bacopa monnieri)
When relevant: Attention, memory, mental fatigue.
Form: Standardized extract, specify bacosides.
Dosage/duration used in research: 300 mg/day, 12 weeks in a newer study.
What to watch out for: Potential digestive issues; effects are measured in weeks, not hours.
What is the difference between milligrams on the label?
"300 mg of extract" and "300 mg of plant powder" are not the same. In herbal supplements, the plant part, extraction ratio, and standardization are important. In the case of magnesium, it is necessary to check the elemental magnesium content, and for omega-3, not the weight of fish oil, but the separately indicated milligrams of EPA and DHA. For probiotics, precise strain codes are important.
How to evaluate if a supplement is helping?
Before starting, it is worth recording your baseline state: stress rating 0–10, time to fall asleep, number of night awakenings, morning freshness, and tolerance for mental work. Evaluate over the period used in the specific study. If adverse reactions occur, discontinue use and consult a specialist.
Frequently Asked Questions
Do all of these supplements lower cortisol?
No. Part of the research measured perceived stress, sleep, mood, or fatigue, rather than cortisol. Direct cortisol reduction has been studied more clearly for ashwagandha and, in a small study of physical exertion, for phosphatidylserine.
Does a higher dose mean a stronger effect?
Not necessarily. In the saffron study, 28 mg per day yielded better results than 22 mg, but that does not mean a larger dose would be more useful. The dosage cannot be separated from the specific extract.
What to choose if mental performance is most important?
In the context of short-term tension, it is worth exploring L-theanine, in studies related to fatigue, rhodiola, and for longer-term evaluation of cognitive functions, bacopa.
Can several supplements be combined?
Just because substances act through different mechanisms does not prove the safety or efficacy of a combination. Combinations are especially important to consider when taking medications or in cases of thyroid, liver, or kidney diseases.
When is fatigue not just stress?
If the fatigue is new, getting worse, severe, or accompanied by weight changes, shortness of breath, fainting, fever, or other symptoms, it is worth investigating the cause with a doctor rather than masking it with supplements.
Scientific sources
- Ashwagandha – clinical study or scientific information source
- Rhodiola (Rhodiola rosea) – clinical study or scientific information source
- L-theanine – clinical study or scientific information source
- Phosphatidylserine – clinical study or scientific information source
- Magnesium – clinical study or scientific information source
- Omega-3 (EPA and DHA) – clinical study or scientific information source
- Saffron extract – clinical study or scientific information source
- Glycine – clinical study or scientific information source
- Lemon balm (Melissa officinalis) – clinical study or scientific information source
- Specific psychobiotics – clinical study or scientific information source
- Magnolia and Phellodendron extract complex – clinical study or scientific information source
- Bacopa (Bacopa monnieri) – clinical study or scientific information source
- NCCIH: effectiveness and safety of ashwagandha
This text is intended for educational purposes. Dietary supplements are not a substitute for medication or individual medical examination. When publishing, product advertisements must separately evaluate EU-authorized health claims; a clinical trial result is not in itself permission to claim that a product treats stress or disease.
