M was diagnosed with a dairy and soy allergy when he was 3 months old.
His pedi said some babies outgrow the allergies by 6 months, and I could
try reintroducing those products back into my diet as a test to see if
he still has a problem. I'm not really sure how I should do that though.
His tell-tale allergy sign was blood in his stool, but now he's eating
solids, so his stools are much different than they used to be. Would I
still be able to notice a tiny speck of blood? I ate a small piece of
cheese on Saturday, and he seemed fussier than usual on Saturday night,
but I don't know if that's related to the cheese or a coincidence. We also went to a party on Saturday, so he could've been overstimulated. I
didn't notice any blood in his diaper. Sigh. This is going to be harder
than I thought. I could go gung-ho and eat a huge plate of mac and
cheese or something (oh God that would be divine), but I don't want to
eat so much that I screw him up for a week if he's still allergic. How
did others test these allergies? When did your LO outgrow them?

Re: Reintroducing dairy/soy? How?
Does that mean you didn't reintroduce dairy into your diet until C was 1 year?
I've also been wondering what happens if M is still allergic at 1 year. I don't mind extended BFing if he needs it due to allergies, but I really want to ditch my pump in August!
Yup. But, I never had to be very strict to begin with (I still had soy, goat/sheep cheese).
I think 6mo is too young
I re-introduced dairy into my diet when DD was 9.5 mo old, OMG that 1st scoop of real ice cream was DIVINE!! I ate it and she was fine!! so then I gave her dairy - baby yogurt (immediate allergic reaction - face all red), Greek yogurt - the same; cheeses - the same (this was over a period of weeks).
I was able to eat dairy at that point and tried giving her cow dairy at 12.5mo (waited til after her b-day party), she did fine w/ yogurt and I was able to stop BFing and go to cow milk at 14mo old. so in our case - we lucked out and she outgrew the dairy intolerance but it was a tough 1st year.
I would wait another 3 mos, your DS is just starting solids, it's a lot for his little system, wait til he's on solids for a few months and then drink a glass of milk or have an ice cream cone or mac-n-cheese and see how he reacts over the next several days.
I have no clue about the timing and whether he is old enough, but if you're reintroducing dairy AND soy - you need to do them separately. That way, if he has a reaction you know what the cause is. You can try eating dairy for a week and look for any changes. Then avoid both for another week and then add soy. Ideally you would want to add them a month apart. Some people have a delayed reaction and it could take awhile to see a response or if there is a reaction for the reaction to fully go away.
Also - when he gets older, you can get the blood RAST tests. They only check for true allergies though. You can have an intolerance to a food that is not a true allergy and wouldn't show on the blood test. Skin prick tests provide a lot of false positives for food allergies.
Was the milk allergy diagnosed through testing or observation? DS #3 was diagnosed at seven months through a blood test. He had reactions to BM which first tipped us off. I eliminated milk products and he was better but would still have random hives. We saw an allergist and that's when we found out he is allergic to milk, eggs and peanuts.
What kind of reactions did your LO have? Were they strictly gastrointestinal or were they anaphylactic (hives, throwing up, etc)? You might take him to an allergist just to be sure before you try to start reintroducing things he is truly allergic to.
My twins are 5! My baby is 3!
DS#2 - Allergic to Cashew, Pistachio, Kiwi
DS#3 - Allergic to Milk, Egg, Peanut, Tree Nuts and Sesame