Nutritional roles of lactoferrin.
OBJECTIVE
Until relatively recently, the only significant source of lactoferrin in the diet was human lactoferrin, provided in breast milk. Today, however, bovine lactoferrin, isolated by dairy technology, as well as recombinant human lactoferrin are commercially available and can be added to foods and clinical products with perceived benefits to the consumer. In this review, the potential biological functions of dietary lactoferrin are described and critically examined.


RESULTS
Ingested lactoferrin has been suggested to exert antibacterial and antiviral activities in the intestine, in part through a direct effect on pathogens, but possibly also affecting mucosal immune function. The latter function is most likely mediated by lactoferrin being taken up by cells via a unique receptor-mediated pathway and affecting gene transcription. Lactoferrin has also been shown to enhance iron status of infants and pregnant women, possibly also via the receptor-mediated pathway. In addition, lactoferrin can stimulate intestinal cell proliferation and differentiation, causing expansion of tissue mass and absorptive capacity. On the contrary, lactoferrin has been shown to inhibit carcinogenesis. Recent findings also suggest that oral lactoferrin treatment may have an anti-inflammatory effect on pregnant women, reducing pregnancy complications.


CONCLUSIONS
Lactoferrin treatment may have beneficial preventive and therapeutic effects on infection, inflammation, and cancer as well as enhancing iron status and growth in vulnerable groups.
Lönnerdal
Bo
B
Department of Nutrition, University of California, Davis, California 95616, USA. bllonnerdal@ucdavis.edu