Supplements to reduce cortisol can play an important role in managing stress and supporting overall wellbeing. Cortisol is the body’s primary stress hormone, released by the adrenal glands in response to physical or emotional stress. While cortisol is essential for energy, immune function, and the fight-or-flight response (Sympathetic Nervous System activation), chronically elevated levels can contribute to anxiety, poor sleep, weight gain, and inflammation.

Lowering cortisol naturally can help calm the nervous system, improve mood, and support better stress resilience. In this article, I explore evidence-backed supplements including amino acids, minerals, probiotics, omega-3s, and herbs - helping answer the question of what supplements lower cortisol - to support a balanced stress response and improve overall mental and physical wellbeing.

Supplements to Reduce Cortisol Naturally: L-Theanine

In another study, 30 adults took 200 mg L-Theanine daily for four weeks. They experienced reduced stress, anxiety, and depressive symptoms, and also improved sleep quality and cognitive performance (Hidese et al., 2019).

A further study demonstrated that L-theanine helped calm the brain during a mental stress test, with more alpha waves and lower cortisol levels (Evans et al., 2021). Overall, these findings suggest L-theanine supports mental health, stress management, sleep, and focus.

Ask your Naturopath to consider whether prescribing L-Theanine is right for you.

Magnesium: Supporting Healthy Stress Hormones

The next worthy supplement is magnesium. Magensium helps reduce cortisol and strengthens the body’s stress response. In a study of adults, 350 mg of Magnesium was taken daily for 24 weeks which significantly lowered cortisol and improved enzyme activity that regulates cortisol, suggesting it may help the body manage stress more effectively (Schutten et al., 2021).

Similarly, amateur rugby players taking 500 mg daily for four weeks had lower cortisol before and during games, and reduced markers of inflammation (Dmitrasinovic et al., 2016). Therefore, magnesium appears to support both mental and physical wellbeing by moderating stress hormones.

Having adequate magnesium reserves in your body is essential to a healthy stress response. Consider a HTMA to ascertain how much you require.

Probiotics for Cortisol Reduction

Another worthy supplement is probiotics. Certain probiotics may support a healthier stress response and reduce cortisol levels. For example, a meta-analysis of 46 randomized controlled trials found that single-strain probiotics lowered cortisol (Jain et al., 2024). Another large review of many studies found probiotics modestly improved mental wellbeing, reducing stress, anxiety, low mood, and cortisol levels (Ben Fredj et al., 2026).

Some single strains, such as Lactobacillus plantarum P-8, improve stress and anxiety in high-stress adults (Ma et al., 2021). This likely results from gut microbiome changes, which regulates the gut–brain axis, influencing emotional wellbeing. Importantly, the improvements are not just due to increased bacterial diversity, but to shifts in microbial function, supporting a calmer, more balanced stress response (Ma et al., 2021).

Consider speaking with your naturopath about adding a high-quality probiotic to your routine to help reduce anxiety.

Omega-3 Fatty Acids: Another Low Cortisol Supplement

A large study of over 2,700 adults found higher omega-3 levels, including DHA, were linked to lower evening cortisol, reduced inflammation, and calmer heart rates -all indicators of a calmer stress response (Thesing et al., 2018). Another study in men undergoing alcohol rehabilitation showed fish oil for three weeks lowered basal cortisol throughout the day, although peak stress responses occurred earlier (Barbadoro et al., 2013). Overall, taking an omega-3 high quality supplement daily can support stress regulation and overall wellbeing, and nearly everyone should consider this.

Herbs to Decrease Cortisol: Withania somnifera (Ashwagandha) 

Not only can supplements help reduce high cortisol levels, but herbs such as Withania somnifera, commonly known as Ashwagandha, are also well-researched and highly effective for reducing anxiety and cortisol (and depression and insomnia) (Speers et al., 2021). For instance, studies suggest Ashwagandha modulates the hypothalamic-pituitary-adrenal (HPA) axis, lowering stress hormone levels (Lopresti et al., 2019).

A systematic review of clinical trials examining the effect of Ashwagandha supplementation on stressed individuals found that it significantly reduces cortisol without major adverse effects. Although, long-term safety studies are still lacking, so use under a qualified health practitioner is recommended (Porta et al., 2023).

In another study, participants had a significant reduction in serum cortisol. They also reported improvements in their stress, anxiety levels and mood . These results show that Ashwagandha produces real, felt reductions in stress and anxiety (West et al., 2026) and should be considered with your Naturopath as part of your anxiety reducing regime. 

Herbs to Lower Stress Hormones: Magnolia Bark and Phellodendron 

Another couple of herbs have been shown to be effective too. A four-week study in adults with moderate stress showed that a combination of Magnolia and Phellodendron bark extracts significantly reduced salivary cortisol by 18%. Participants also reported improved mood and reduced tension, depression, anger, fatigue, and confusion, while experiencing higher vigour and overall wellbeing (Talbott et al., 2013).

These natural extracts appear to be an effective approach for lowering stress hormones and supporting daily mood.

Our Final Cortisol Reduction Supplement: Rhodiola rosea

Lastly, Rhodiola rosea has been studied for its effects on stress, fatigue, and burnout. Clinical and preclinical studies indicate that supplementation reduces cortisol responses to stress, improves mental performance, and alleviates stress-related symptoms (Stojcheva and Quintela, 2022). Consequently, Rhodiola may help support resilience and moderate the physiological stress response during periods of chronic stress. This is the last important herb for you and your Naturopath to consider in lowering your cortisol levels. 

Conclusion

Addressing the Root Cause of Stress and Anxiety

Effectively managing stress requires a combination of lifestyle strategies and targeted nutrition. Providing the body with essential minerals and nutrients is key to addressing the root cause of anxiety. In some cases, imbalances such as copper excess or other heavy metal accumulation may contribute, and restoring mineral balance can support noticeable improvements. In addition, supplements to reduce cortisol can support the body’s stress response, lower cortisol, and promote a calmer, more balanced mood. Evidence-backed options such as L-theanine, magnesium, probiotics, omega-3 fatty acids, and adaptogenic herbs like Ashwagandha, Rhodiola, Magnolia, and Phellodendron may support both mental and physical wellbeing.

Building a Sustainable Stress Response

However, supplements work best alongside healthy habits, including adequate sleep, regular movement, mindfulness practices, and a nutrient-rich diet. Together, these approaches help manage stress, support hormone balance, and protect against the effects of chronically elevated cortisol. Ultimately, by understanding how cortisol affects the body and choosing the right strategies to lower it, including what supplements lower cortisol, you can support resilience, reduce anxiety, and feel more in control of your stress levels.