Effects of a nutritional intervention with yogurt on lymphocyte subsets and cytokine production capacity in anorexia nervosa patients.

BACKGROUND

The benefits of probiotic therapy in immunocompromised subjects still need strong scientific evidences.

AIM OF THE STUDY

To assess the effects of yogurt on certain immunological parameters in anorexia nervosa (AN) patients during refeeding.

METHODS

A parallel 10-week nutritional intervention with yogurt was conducted on a group of patients with AN and on a group of healthy adolescents (HA). In total, 16 AN patients and 16 HA consumed 375 g/d of yogurt containing L. bulgaricus and S. thermophilus (groups AN-y and HA-y, respectively). The control groups for AN patients (n = 14) and healthy subjects (n = 19) consumed 400 ml/d of semi-skimmed milk (groups AN-c and HA-c, respectively). Blood lymphocyte subsets were assessed by flow cytometry and the in vitro production of IL-2, IFN-gamma, IL-1, IL-6 and TNF-alpha by PHA-stimulated PBMC was measured by ELISA.

RESULTS

A significant combined effect of time and nutritional intervention was found for the CD8+ subset and IFN-gamma production, both in HA and AN patients. The CD8+ subset showed a significant increase after 10 weeks in HA-c and AN-c. As a consequence, the CD4+/CD8+ ratio was significantly lower in AN-c than in AN-y after treatment. A significant increase in IFN-gamma production was found after yogurt intake in AN-y, while it decreased significantly in AN-c.

CONCLUSION

The findings suggest that the inclusion of yogurt in the refeeding therapy of AN patients may exert positive effects on the immunological markers related to the nutritional status of these patients, such as the CD4+/CD8+ ratio and the production of IFN-gamma by lymphocytes.