Mediterranean Diet

Because of the prevalence of anxiety during pregnancy, a study was conducted at a hospital in Spain to see if the Mediterranean diet could help prevent this condition (Casas et al., 2023).  This study was a randomized controlled trial, where 680 women whose pregnancies were considered to be high risk were randomly assigned to either follow a Mediterranean diet, or simply receive standard care.  The Mediterranean diet included extra-virgin olive oil (two liters per month) and walnuts (15 grams per day), whole grains, fruits and vegetables, legumes, dairy, fish, and white meat.  The women began their participation during their second trimester, and their anxiety levels were measured with a questionnaire that had been validated to ensure its accuracy.  They completed the questionnaire again about a month before their due dates, and the women who had been following the Mediterranean diet had lower anxiety levels than those who simply received standard care.  Not only that, they reported lower levels of perceived stress, they scored better on the well-being questionnaire, and they were sleeping better at night, which would be greatly appreciated by any pregnant woman approaching her due date.

Cortisol is a hormone involved with stress, and in this study, cortisol levels were measured in the women’s urine, along with cortisone, which is the inactive form of the hormone.  These two levels were used to estimate how much of an enzyme called 11β-Hydroxysteroid Dehydrogenase Type 2 the women were producing, since this enzyme converts cortisol to inactive cortisone.  Estimated levels of this enzyme were higher in the women on the Mediterranean diet, indicating that the diet was helping them to deactivate their stress hormones, resulting in lower anxiety levels.  The authors go on to describe other studies where specific foods found in the Mediterranean diet that are high in antioxidants and omega-3 fatty acids such as the whole grains, fruits and vegetables, legumes, extra-virgin olive oil and nuts, were associated with lower levels of anxiety, while ultra-processed foods, red meat, processed meat, margarine and artificial juice were associated with higher levels of anxiety. 

Reference:

Casas, I., Nakaki, A., Pascal, R., Castro-Barquero, S., Youssef, L., Genero, M., Benitez, L., Larroya, M., Boutet, M. L., Casu, G., Gomez-Gomez, A., Pozo, O. J., Morilla, I., Martínez-Àran, A., Vieta, E., Gómez-Roig, M. D., Casas, R., Estruch, R., Gratacos, E., … Crovetto, F. (2023). Effects of a Mediterranean Diet Intervention on Maternal Stress, Well-Being, and Sleep Quality throughout Gestation-The IMPACT-BCN Trial. Nutrients, 15(10).