Le bâillement, du réflexe à la pathologie
Le bâillement : de l'éthologie à la médecine clinique
Le bâillement : phylogenèse, éthologie, nosogénie
 Le bâillement : un comportement universel
La parakinésie brachiale oscitante
Yawning: its cycle, its role
Warum gähnen wir ?
 
Fetal yawning assessed by 3D and 4D sonography
Le bâillement foetal
Le bâillement, du réflexe à la pathologie
Le bâillement : de l'éthologie à la médecine clinique
Le bâillement : phylogenèse, éthologie, nosogénie
 Le bâillement : un comportement universel
La parakinésie brachiale oscitante
Yawning: its cycle, its role
Warum gähnen wir ?
 
Fetal yawning assessed by 3D and 4D sonography
Le bâillement foetal
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mystery of yawning 

 

 

 

 

mise à jour du
19 juin 2018
Clinical Research in Neurology
2018;1(1):1-4
Elevation of Cortisol Levels by Ingesting Liquorice
Simon B. N. Thompson, Dilara Sava
Department of Psychology, Faculty of Science & Technology

Chat-logomini

Abstract
The effects of liquorice on the hormone cortisol are known but are not well understood. It has been noted anecdotally, but there remains little scientific literature on the link between the effects of liquorice on the body and the fact that cortisol is consistently implicated. This study demonstrates the link between liquorice and cortisol and the role that cortisol plays, together with yawning, in regulating brain temperature which is often compromised in certain neurological disorders such as multiple sclerosis. 13 volunteers aged between 21 and 28-year-old ingested liquorice as well as completing the Hospital Anxiety and Depression Scale, General Health Questionnaire, and demographic and health details. Saliva cortisol samples were collected before and after ingesting liquorice. In all cases, cortisol levels were significantly elevated after ingesting liquorice.
 
Résumé
Les effets de l'ingestion de réglisse sur le cortisol sont connus mais ne sont pas bien compris. Des données anecdotiques, mais peu de littérature scientifique ont évoqué un lien entre les effets de la réglisse sur le corps et le fait que le cortisol est systématiquement impliqué. La présente étude démontre un lien entre la réglisse et le cortisol et le rôle que joue le cortisol, associé au bâillement, dans la régulation de la température cérébrale souvent compromise dans certains troubles neurologiques comme la sclérose en plaques. 13 volontaires âgés de 21 à 28 ans ont ingéré de la réglisse et ont rempli l'échelle d'anxiété et de dépression de l'hôpital, le questionnaire général sur la santé et les données démographiques et de santé. Des échantillons de cortisol salivaire ont été prélevés avant et après l'ingestion de réglisse. Dans tous les cas, les taux de cortisol étaient significativement élevés après ingestion de réglisse

Thompson Cortisol Hypothesis : all the publications
INTRODUCTION
 
The hormone cortisol has been associated with yawning and has been described in the Thompson Cortisol Hypothesis[1,2] that suggests links the rise in cortisol triggers which in turn lowers brain temperature. Threshold level rises of cortisol are proposed to be part of a complex mechanism since brain temperature can rise dramatically in people with MS[3] possibly due to excessive fatigue and irregular sleep patterns.[4] Cortisol is thought to regulate brain temperature within the hypothalamus-pituitary-adrenal (HPA)-axis,[5] which is a natural feedback loop to protect our bodies,[6] and cortisol may communicate directly with the motor cortex[7] as evidenced in mice by Hasan et al.[8] where sophisticated cortisol-specific receptors were involved during motor learning tasks.
 
Cortisol is implicated during stressful events and might be modulated by contagious yawning.[9] Curiously, the hormone is thought to rise during ingestion of liquorice because of the effects of the main ingredient, glycyrrhizic acid[10] on the kidneys. This may be because of inhibition of the enzyme 11_-hydroxysteroid dehydrogenase type 2 which normally inactivates cortisol in the kidney. Liquorice is likely to inhibit this enzyme and so results in increases in cortisol levels. Since the first description of side effects of liquorice,[11] some researchers have found that girls exposed to high maternal liquorice consumption through mothers during pregnancy had higher body mass index for age and reported more advanced pubertal development as compared with boys.[12] Støving et al.[13] suggested that increased sensitivity to glycyrrhizic acid may also arise in anorexia nervosa which may cause severe hypokalemia when combined with bizarre eating habits. Anecdotally, it would seem that people can overdose on liquorice consumption[14] which can cause rhabdomyolysis, the breakdown of skeletal muscle causing the release of myoglobin into the bloodstream.[15] Myoglobin is the protein that stores oxygen in muscles; too much myoglobin in the blood can lead to kidney damage.
 
Ottenbacher and Blehm[16] found that liquorice ingestion can lead to increased hypertension and others have shown that there may be many complications arising from liquorice consumption[17] including preterm labor,[18] and ocular complications.[19,20] The link between cortisol and yawning is now established,[1,7] and it is interesting to note that liquorice may now also play a role in creating artificially induced levels of the hormone for effects that might be used usefully for diagnosis or treatment monitoring.
 
DISCUSSION
 
This study presents interesting findings in respect of cortisol elevations. The level of cortisol found in the first saliva samples was lower than that found in the second sample after participants had ingested liquorice. Furthermore, a significant difference was found between the levels of cortisol in the first sample compared with the second sample after liquorice ingestion. This concords with studies that have suggested liquorice ingestion acts on the receptors responsible for cortisol release and causes elevation in blood.[10]
 
Despite reports of possible side effects of liquorice ingestion in terms of its effects on body organs and functionality, it appears that it may be worthwhile investigating further this natural plant for its potential properties in affecting cortisol levels, especially in those who are affected by low cortisol production or an irregular release of the hormone, such as Cushing's syndrome.[27]
The authors acknowledge that it is a small sample study but also that it supports previous findings that indicate liquorice may be a natural product with potentially far-reaching benefit.