Greek yogurt does have probiotics, however if your yogurt also contains sugar, that cancels out most healthful benefits. Additionally, yogurt has only a small number of probiotics, not nearly enough to repopulate a gut that's out of balance and support the immune system as it needs.

Brenda Watson says it best, so I'm going to share 4 points she mentioned on her last PBS special, "The Road to Perfect Health". They clearly state what would be best to look for in a probiotic:

1. Look for high culture count. The culture count refers to the total amount of live, friendly bacterial cultures in a single serving. You need a least 15 billion cultures to begin to make an impact on your health—often more depending upon age or health-related concern. The more probiotics the better when it comes to the culture count in probiotic supplements.

2. Check out the number of strains. There are over 1,000 strains of beneficial bacteria in the gut. A good rule of thumb is that a variety of strains more closely resemble the diversity that naturally exists in the gut. Look for the naturally occurring strains that begin with Ls and Bs, like lactobacilli and bifidobacteria. A good way to remember is that the L strains are good for the little (small) intestine. The B strains are good for the big (large) intestine or colon. It’s also important to get a variety of strains because each person’s body has a different bacterial footprint and utilizes some bacterial strains better than others. Cover all the bases with one supplement for best results.

3. Make sure the capsule is designed for delayed release. Probiotics must travel through the harsh stomach environment and be delivered to the intestines to be effective. If they never make it through the stomach acid, they won’t do you any good. Delayed-release capsules are engineered to remain intact through the stomach and begin dissolving in the intestine, where they are needed most.

4. Look for potency at time of expiration, not manufacture. Any probiotic is fresh when manufactured, but very few remain at full strength through their expiration date. A probiotic supplement, when delivered to the right place, with the right amount of cultures and strains, can help promote digestive health, bowel regularity and strengthen the body’s natural immune defenses. Be sure to read the label, so you’ll know you’re giving your body the probiotic it needs.