A large analysis reviewed available research and determined that probiotics help lower blood pressure by improving lipid profiles, reducing insulin resistance, regulating renin levels (a protein and enzyme secreted by the kidneys to lower blood pressure) and activating antioxidants. Researchers consider them valuable prospects in the treatment of high blood pressure because their side effects are generally minimal or nonexistent. (82, 83)
The best case for probiotic therapy has been in the treatment of diarrhea. Controlled trials have shown that Lactobacillus GG can shorten the course of infectious diarrhea in infants and children (but not adults). Although studies are limited and data are inconsistent, two large reviews, taken together, suggest that probiotics reduce antibiotic-associated diarrhea by 60%, when compared with a placebo.
Even if some of the bacteria in a probiotic managed to survive and propagate in the intestine, there would likely be far too few of them to dramatically alter the overall composition of one's internal ecosystem. Whereas the human gut contains tens of trillions of bacteria, there are only between 100 million and a few hundred billion bacteria in a typical serving of yogurt or a microbe-filled pill. Last year a team of scientists at the University of Copenhagen published a review of seven randomized, placebo-controlled trials (the most scientifically rigorous types of studies researchers know how to conduct) investigating whether probiotic supplements—including biscuits, milk-based drinks and capsules—change the diversity of bacteria in fecal samples. Only one study—of 34 healthy volunteers—found a statistically significant change, and there was no indication that it provided a clinical benefit. “A probiotic is still just a drop in a bucket,” says Shira Doron, an infectious disease expert at Tufts Medical Center. “The gut always has orders of magnitude more microbes.”
Digestive tract conditions. Probiotic supplements may be useful in treating and preventing inflammatory conditions, such as pouchitis (which affects people who have their colons removed), inflammatory bowel diseases (such as ulcerative colitis and Crohn's disease), and chronic stomach inflammation and ulcers caused by Helicobacter pylori bacterium. They may also be helpful in treating constipation, irritable bowel syndrome, acid reflux, spastic colon; shortening the duration of infectious diarrhea; and reducing the recurrence of bladder and colorectal cancer. Some studies suggest that yogurt is helpful in preventing diarrhea - a common side effect of treatment with antibiotics. It has also been shown to prevent or treat urinary tract infections and vaginal yeast infections in women. 

If you have an immune system problem or another serious health condition, you may have a greater chance of issues. Some reports have linked probiotics to serious infections and other side effects. The people most likely to have trouble are those with immune system problems, people who've had surgery, and others who are critically ill. Don't take probiotics if you have any of those issues.
Probiotics and raw fermented foods and drinks, such as sauerkraut and kefir that contain probiotic-like microbes, are very helpful for digestion. They help to keep your gastrointestinal tract at the proper pH for optimal digestion and help to break down foods. They also regulate the motion of your intestines so that food moves through at the proper pace.
Though most probiotics are formulated for both men and women, Garden of Life’s Raw Probiotics for Women is manufactured with women in mind. This probiotic has a whopping 85 billion live cultures and 32 different probiotic strains to target everything from gut and vaginal health to thyroid and nutrient absorption. It contains two popular probiotics, Lactobacillus acidophilus and Bifidobacterium, and is gluten-free, soy-free, and made without fillers or binder—which is great for anyone with dietary restrictions or allergies. Each container comes with 90 capsules; the recommended dose is three capsules per day.
After the antibiotics had cleared the way, the standard probiotics could easily colonize the gut of everyone in the second group, but to the team's surprise, this probiotic colonization prevented the host's normal microbiome and gut gene expression profile from returning to their normal state for months afterward. In contrast, the aFMT resulted in the third group's native gut microbiome and gene program returning to normal within days.
DNA Shift is a once-daily, powerful probiotic delivering 50 billion CFUs and 11 probiotic strains. It’s perfect for both men and women who want to improve their gut and brain health. With long-term use, you may even see improved mood and energy levels. This probiotic can help relieve the following: symptoms of gas and bloating, constipation indigestion, irregularity, leaky gut, and diarrhea induced by antibiotics.
Two large-scale clinical trials recently reported in the New England Journal of Medicine suggest that the situation in infectious diarrhoea might also be more complex than previously believed. Freedman and colleagues did a randomised controlled trial of a probiotic containing Lactobacillus rhamnosus and Lactobacillus helveticus in children presenting to the emergency department with gastroenteritis. Contrary to expectations, they found that the probiotic did not prevent development of moderate-to-severe gastroenteritis within 14 days after enrolment. In a separate study, Schnadower and colleagues found similar results with L rhamnosus GG alone. Both trials used probiotics that are available over the counter in North America and showed no significant difference from placebo in the duration of diarrhoea and vomiting, number of unscheduled health-care visits, or length of absence from day care. These results cannot be generalised to other probiotic strains or preparations, but they do show that we have some way to go in elucidating which probiotics might provide benefits in which clinical settings.
Better Health Review ranks Ultimate Flora as the most effective probiotic supplement. It contains 30 billion active bifidobacteria for colon health, and 20 billion lactobacilli and lactococcus cultures for the small intestine. According to Better Health Review, it contains all natural ingredients. It earns a perfect 5 score from Better Health Review, and the magazine “Vitamin Retailer” voted it best two years in a row.