Original Article | Published:

Impact of consuming a milk drink containing a probiotic on mood and cognition

European Journal of Clinical Nutrition volume 61, pages 355361 (2007) | Download Citation

Guarantor: D Benton.

Contributors: DB was responsible for the design and analysis while CW and AB ran the study and collected the data.




The impact on mood and memory of consuming a probiotic containing milk drink, or a placebo, was examined as, previously, a poor mood has been found to correlate with the frequency of constipation.


A double-blind placebo-controlled trial with random allocation of subjects.


Subjects went about their normal life in the community apart from three visits to the laboratory.


One hundred and thirty-two healthy members of general population, mean age 61.8 years, volunteered in response to local media coverage. One hundred and twenty-four finished the trial.


For a 3-week period, either a probiotic containing milk drink, or a placebo, were consumed daily. Mood and cognition were measured at baseline, and after 10 and 20 days of consumption.


At baseline those who reported themselves to be less frequently constipated were more clearheaded, confident and elated. Although the taking of the probiotic did not generally change the mood, this appeared to be a reflection of the generally good mood in this sample. When those in the bottom third of the depressed/elated dimension at baseline were considered, they selectively responded by reporting themselves as happy rather than depressed after taking the probiotic. The intervention did not, however, influence the reported frequency of defaecation, probably a reflection of the initially low incidence of constipation. An unexpected and possibly chance finding was that the consumption of probiotics resulted in a slightly-poorer performance on two measures of memory.


The consumption of a probiotic-containing yoghurt improved the mood of those whose mood was initially poor. This improvement in mood was not, however, associated with an increased frequency of defaecation.


Funded by Yakult, Japan.

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  1. , (2006). Executive function and the frontal lobes: a meta-analytic review. Neuropsychol Rev 16, 17–42.

  2. (2001). Well-being, gastro-intestinal function and other reactions to food. Proc Nutr, Soc 6, 190A.

  3. , (1999). The effects of nutrients on mood. Public Health Nutr 2, 403–409.

  4. , (2006). Probiotics and chronic disease. J Clin Gastroenterol 40, 270–274.

  5. , , , (2000). Leisure time physical activity in Australian women: relationship with well being and symptoms. Res Q Exerc Sport 71, 206–216.

  6. , , , , (1987). Do patients with disordered defecation have a primary personality disorders? Gut 28, A1373.

  7. , (1997). Quality of life in patients with different types of functional constipation. Quality of life in patients with different types of functional constipation. Scand J Gastroenterol 32, 1083–1089.

  8. , , (1977). Some methodological problems with feeling of knowing studies. Acta Psychologia 41, 365–371.

  9. , , (1986). Assessing intellectual deterioration. Br J Clin Psychol 25, 119–124.

  10. , , , , , (1992). Defecation and timing and stool form in the general population: a prospective study. Gut 33, 818–824.

  11. (2001). Prophylactic and therapeutic uses of probiotics: a review. J Am Dietet Assoc 101, 229–238.

  12. (2000). The feeling of knowing: some metatheoretical implications for consciousness and control. Consciousness Cogn 9, 149–171.

  13. , , (1998). The relation between irregular bowel movement and the lifestyle of working women. Hepato-Gastroenterology 45, 956.

  14. , (2005). Major depressive disorder: probiotics may be an adjuvant therapy. Med Hypotheses 64, 533–538.

  15. , (1984). Profile of mood states. Educational and Industrial Testing Service: San Diego.

  16. , (1991). National Adult Reading Test (NART), 2nd edn. NFER-Nelson: Windsor.

  17. (2006). Constipation in older patients: effects on quality of life. Br J Nurs 15, 188–192.

  18. (2006). Emotion and cognition: insights from studies of the human amygdala. Annu Rev Psychol 57, 27–53.

  19. , , (1984). Psychiatric assessment of patients with severe constipation. Gut 25, A582.

  20. , (1992). Participation in physical activity and cardiovascular fitness have different effects on mental health and mood. J Psychosomat Res 36, 657–665.

  21. , , , (1992). Psychological evaluation of patients with severe idiopathic constipation. Which instruments to use? Am J Gastroenterol 87, 977–980.

  22. , , (1989). Psychological and physiological characterististics of patients with severe idiopathetic constipation. Gastroenterology 97, 932–937.

  23. (1998). Wechsler Memory Scale 3rd Edn. (WMS-III) The Psychological Corporation: London.

  24. (2004). Contributions of metaknowledge to retrieval of natural categories in semantic memory. J Exp Psychol Learn Mem Cogn 30, 909–916.

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The funding of this study by Yakult, Japan is gratefully acknowledged.

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  1. Department of Psychology, University of Wales Swansea, Wales, UK

    • D Benton
    • , C Williams
    •  & A Brown


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Correspondence to D Benton.

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