Hi Johanne, my sister in law is right up on these sort of topics. I recently changed my son from cows to goats milk (fresh not formula) as he was always mucusy. I asked my sister in law for advice as I too was thinking soya. She said there is a lot of new study out showing that soya is not suitable for babies as it has a very high natural form of female hormones in it. I just changed him straight to goats milk and he really likes it!! I guess this would be the same for either fresh or formula. My sister in law reads anything she can relating to this subject and explores further into things. Her son has a lot of medical problems so she needs to be on top of everything.Hope this helps.