As far as I am concern, unless lactoferrin has direct affect on...

As far as I am concern, unless lactoferrin has direct affect on the activity of secretion of lactase or/and alter the molecular structure of lactose in human gut then there will be no affect when it comes to lactose intolerance. Also, when it comes to “antimicrobial” properties of lactoferrin, by default you need to maintain a good flora of bacteria in your gut, the good bacteria. Antimicrobial effects that alter the balance of such bacteria would have profound detrimental impact on gut health. This is why doctors often prescribe probiotics to be taken along with antiobiotics. The profound effect of which, I would assume to be more pronounced in infants if not downright dangerous.