The fast-paced routine and continuous information overload have transformed stress and anxiety into almost constant presences in modern day-to-day life. In an attempt to find a counterpoint to this frenetic pace, thousands of people have revived the ancestral habit of preparing calming teas before bed.
And modern medicine has focused on the biochemistry of these herbs to understand their real neurological impact. The finding is clear: nature has powerful chemical tools to intervene in our mental health.
To decipher which infusions truly deliver evidence-based results, the CNN Brazil spoke with doctor Inácia Simões, specialist in Anesthesiology and Pain at the Saint Moritz Clinical Center.
She explains that tradition finds strong support in current science. “Based on medical literature, five examples of teas with calming properties include chamomile, valerian, passionflower (passionflower), lavender and lemon balm (lemon balm)”, says the doctor.
These herbal medicines do not act through a placebo effect; according to the expert, “these teas demonstrate sedative properties in clinical studies, with mechanisms of action that mainly involve the modulation of the GABAergic system”.
The chemistry of relaxation and the power of GABA
To understand how a simple cup acts on the brain, you need to look at neurotransmitters. This occurs, in large part, due to hyperactivity of neuronal networks.
According to the expert, most of these herbal herbs act by modulating the GABAergic system, which is exactly the same target as conventional pharmaceutical anxiolytics. The big advantage, however, is in the profile, which offers this relaxation with fewer cognitive adverse effects and a lower risk of withdrawal symptoms.
The doctor highlights that the role of these plants in the body is systemic and complex. Additional mechanisms include modulation of monoaminergic and serotonergic pathways, regulation of the hypothalamic-pituitary-adrenal axis, and important anti-inflammatory effects.
The top 5 herbs with proven neurological action
Medical literature breaks down the clinical behavior of each of these five herbs, revealing that each plant has its own specialties and characteristics in combating stress and insomnia.
- Chamomile (Matricaria recutita): one of the most popular plants in the world, chamomile has notable anxiolytic, sedative and antinociceptive effects (capable of inhibiting the perception of pain). Its effectiveness is explained by GABAergic modulation and inhibition of the FAAH enzyme, which metabolizes endocannabinoids. It also contains glucuronoxylan, a compound with direct action on the central nervous system. Its effectiveness has been demonstrated in systematic reviews and meta-analyses of randomized clinical trials, although the literature points to a high risk of bias in these studies.
- Valerian (Valeriana officinalis): known for its strong aroma, this root focuses on sedative and anxiolytic effects through the direct modulation of GABA-A receptors and its action on the GABAergic system. Although the evidence is considered inconclusive due to the low number of robust studies, the plant has been clinically identified as one with the greatest potential for treating anxiety-related insomnia.
- Passionflower / Passiflora (Passiflora incarnata): the leaves of this tropical plant deliver classic anxiolytic and sedative effects via GABAergic modulation. Doctor Inácia highlights that there is promising evidence in meta-analysis networks, pointing out that combinations with valerian show better results, achieving efficacy comparable to conventional treatments.
- Lavender (Lavandula angustifolia): more than an aromatherapy ally, ingesting lavender brings anxiolytic effects and direct benefits for depression and insomnia, also through GABAergic modulation. Currently, it has the best evidence available among herbal medicines, with efficacy comparable to first-line treatments. A patented form of the herb, known as Silexan, demonstrates a significant reduction in anxiety scores.
- Lemon balm / Melissa (Melissa officinalis): bringing anxiolytic and calming effects based on GABAergic modulation, lemon balm is considered possibly safe and possibly effective. Evidence from clinical trials strongly supports its use in patients diagnosed with anxiety disorders.
The myth that “natural doesn’t hurt”: safety and risks
There is a popular belief that natural products are free from side effects, which is a huge medical error. Although all of the teas mentioned have favorable safety profiles when compared to conventional medicines, precautions are essential.
The specialist warns about the particularities of each substance. While chamomile and lavender are generally well tolerated with minimal adverse effects, other plants require attention. “Valerian can cause headaches and side effects, with rare hepatotoxicity”, he warns.
The use of passion fruit can cause unwanted sedation and, in high doses, lead to ataxia (loss of coordination) and depression of the central nervous system. Lavender requires caution, as it can increase the sedative effects of narcotics or other pharmaceutical sedatives.
Science still under construction
Despite their broad historical use, the consolidation of these herbs in formal medicine still faces academic barriers. Dr. Inácia remembers that the evidence has clear limitations. Although the results are very promising, many studies have a small number of participants and a high risk of errors.
“Medicine requires that larger clinical trials be conducted with adequate methodological design in order to establish definitive and standardized recommendations. Furthermore, effectiveness in clinical practice can depend drastically on the duration of treatment, the type of patient, the chosen route of administration and the method of preparing the infusion”, he concludes.
