[kolev]

The real yogurt is the Bulgarian yogurt, not low-fat high-sugar ones sold at store in the States. Only an idiot will eat a probiotic "yogurt" with 30g of sugars in the small container and think they are doing good to their health! Fortunately, there are two brands [0] of the original sold at Whole Foods today (one, unfortunately, available only on the East Coast [1]), but they are too sour for the American to like. Does it have questionable benefits? Maybe you should try to research how yogurt got the attention of medicine. It was eaten by my predecessors for centuries and the benefits are without doubt.

When babies are born, their gut is sterile before it gets colonized from outside. The diet definitely can affect which strain will outgrow others, but all gut bacteria is exogenous.

[0] http://www.whitemountainfoods.com/YogurtProductPage.html

[1] http://www.trimonayogurt.com/

[bch]

If one is sufficiently motivated (and can utilize all the product), it's not hard to make ones own yogurt, with starter.

For that case, you could find your favourite local milk and make yogurt who's ingredients you are certain of, because you put them in.

http://www.wikihow.com/Make-Yogurt

[kolev]

This is true and might be surprising that Bulgarians are not accustomed to make their own yogurt, because stores are full of high-quality one that's cheap (unlike the $6-7/jar in the States). Kefir is also great and can also be made at home. My favorite is Lifeway [0].

[0] http://www.lifeway.net/Products/OrganicKefir/WholeMilkKefir/...