Griffonia: origins, benefits, and precautions for use

Griffonia, or Griffonia simplicifolia, is a climbing plant native to West and Central Africa. It belongs to the Fabaceae botanical family. In current uses, it is mainly its seeds that are exploited, as they naturally contain 5-hydroxytryptophan. 5-hydroxytryptophan is an amino acid, i.e., a molecule involved in many biological reactions. In humans, it plays a special role as it is the direct metabolic precursor of serotonin.

The properties attributed to griffonia are based almost entirely on its content of 5-hydroxytryptophan (5-HTP). From a biological perspective, this substance is involved in a well-established metabolic pathway: once absorbed, it is converted into serotonin by a specific enzyme.

Serotonin is a neurotransmitter, that is, a chemical messenger responsible for transmitting signals between nerve cells in the brain. It plays a role in several functions of the central nervous system, particularly those related to sleep, mood and certain cognitive processes.

This mechanism is recognised independently of any nutritional application and is well documented in pharmacological research, notably through data derived from oxitriptan, the medicinal form of 5-HTP.

The effects attributed to griffonia are based exclusively on clinical studies conducted using 5-hydroxytryptophan (5-HTP), rather than the whole plant. These studies were carried out in defined populations and under specific experimental conditions.

In older adults, 5-HTP supplementation has been associated with a reduction in sleep onset latency, measured using objective assessment tools. This effect was observed after four and eight weeks of supplementation, but was no longer statistically significant after twelve weeks of follow-up.

In a different clinical context, individuals with Parkinson’s disease and REM sleep behaviour disorder exhibited changes in certain sleep parameters, without any reported worsening of nocturnal symptoms. In addition, a 12-week controlled trial conducted in elderly participants reported a moderate increase in scores on the Montreal Cognitive Assessment (MoCA), a standardised test used to evaluate overall cognitive function. The same study also observed an increase in circulating serotonin levels.

These findings must be interpreted within their specific experimental frameworks. They cannot be generalised to the broader population, nor can they be used to substantiate health claims.

In the context of food supplements, griffonia is available in various forms, most commonly as capsules containing a standardised extract of 5-hydroxytryptophan (5-HTP). The clinical studies available to date have used clearly defined doses of 5-HTP, for example 100 mg per day in certain trials conducted in older adults. It is important to clearly distinguish these uses from those of medicinal products containing oxitriptan, for which dosages are significantly higher and strictly regulated under a marketing authorisation.

Griffonia is generally taken in the evening because of its physiological mode of action, which is directly linked to the presence of 5-hydroxytryptophan (5-HTP). During the evening and night, serotonin acts as a precursor to melatonin, a hormone involved in the regulation of the biological clock and sleep–wake cycles.

From a chronobiological perspective, evening intake is therefore consistent with the body’s natural rhythms, supporting the mechanisms involved in preparing for sleep and regulating circadian timing. This timing may be relevant when the intended use is to support sleep onset or contribute to sleep quality.

Other natural substances can produce similar effects. 

The most robust tolerance data concern 5-HTP used as a medication. In this context, the reported side effects are mainly digestive, with nausea and vomiting frequently described. Serotonin syndrome is also mentioned as a very rare side effect. This is a set of clinical manifestations related to excessive serotonin activity in the central nervous system. It can include agitation, digestive disorders, increased heart rate, and neuromuscular abnormalities. These factors highlight the need for increased vigilance when several substances acting on serotonin are combined.

The contraindications for griffonia are mainly related to its main active ingredient, 5-hydroxytryptophan (5-HTP), an amino acid naturally present in the body and a direct precursor of serotonin, a neurotransmitter involved in regulating mood, sleep, and appetite.

Griffonia is contraindicated when taken concomitantly with drugs that act on serotonin, such as serotonin reuptake inhibitors, serotonin and norepinephrine reuptake inhibitors, monoamine oxidase inhibitors, or certain migraine treatments. This combination exposes the patient to a risk of serotonin syndrome, a rare but potentially serious condition linked to excess serotonin in the nervous system.

Its use is also not recommended in people with a history of severe psychiatric disorders, particularly bipolar disorder, due to the risk of mood imbalance. As a precautionary measure, griffonia is not recommended during pregnancy and breastfeeding, as there is insufficient clinical data. Finally, anyone suffering from a chronic condition or undergoing medical treatment should seek medical advice before taking it, to ensure appropriate and safe use.

Certain situations warrant particular attention. When used as a medication, 5-HTP is contraindicated in cases of severe renal failure, small intestine carcinoid tumors, or when combined with non-selective monoamine oxidase inhibitors. Drug interactions have been documented with several treatments that increase serotonergic activity, exposing patients to a risk of serotonin syndrome. These data must be taken into account when using dietary supplements containing griffonia, particularly in people undergoing treatment.