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By Amy Norton<\/b>
HealthDay Reporter<\/i><\/p>\n
THURSDAY, July 9, 2020<\/p>\n
Probiotic<\/a> supplements<\/a> might help ease depression<\/a> symptoms in some people, a new research review suggests.<\/p>\n Researchers found that across seven small clinical trials<\/a>, various probiotics<\/a> seemed to improve symptoms in patients with clinical depression<\/a> — at least in the short term.<\/p>\n The studies build on a growing research interest in the role of gut health — specifically, the balance of bacteria dwelling there — and brain health.<\/p>\n But experts stressed that the probiotic<\/a> trials had a number of limitations, and it’s too soon to draw any conclusions.<\/p>\n For one, a “placebo effect” cannot be ruled out, according to Sanjay Noonan, the lead author on the research review.<\/p>\n And, he said, besides being small, the trials did not look at the longer term: All lasted about two to three months.<\/p>\n According to Noonan, “no definitive statements can be made” on whether people with depression<\/a> stand to benefit from probiotics<\/a>.<\/p>\n “It would be conjecture to try and suggest anything about the long-term efficacy of probiotic therapy,” he said.<\/p>\n Noonan and his colleagues at Brighton and Sussex Medical School in England reported the findings July 6 in the journal BMJ Nutrition<\/a>, Prevention<\/a> & Health.<\/i><\/p>\n Probiotics<\/a> are live bacteria and yeast that naturally dwell in the body. Probiotic supplements<\/a> are marketed as a way to restore a healthier balance of good bacteria.<\/p>\n The digestive system<\/a>, in particular, hosts a vast array of bacteria and other microbes — known as the “gut microbiome.” And those organisms are believed to do more than just aid in digestion<\/a>.<\/p>\n Research suggests the microbes are involved in everything from immune defenses to producing vitamins<\/a>, anti-inflammatory compounds, and even chemicals that influence the brain.<\/p>\n Meanwhile, a number of studies have linked the makeup<\/a> of the gut microbiome to the risks of various health conditions. These include brain-based conditions like Alzheimer’s<\/a> and autoimmune diseases like type 1 diabetes<\/a> and rheumatoid arthritis<\/a>.<\/p>\n In a 2019 study, researchers found that people with depression<\/a> showed differences in specific gut bacteria, versus those without depression<\/a>. Levels of two types of bacteria — Coprococcus<\/i> and Dialister<\/i> — were reported to be “consistently depleted” in people with depression<\/a>.<\/p>\n But none of that proves a lack of those bacteria, or any others, actually helps cause depression<\/a>. And for now, no one knows if any probiotics<\/a> can help treat it.<\/p>\n “It’s important to stress<\/a> that this area of research is in an extremely early phase,” Noonan said.<\/p>\n He said the point of this review was to look at the existing evidence on probiotics, and not to offer answers.<\/p>\n The trials in the review each contained fewer than 100 people. And they most often tested any of three probiotic strains<\/a>: L. acidophilus<\/i>, L. casaei<\/i> and B. bifidum<\/i>. One trial tested a probiotic combined with a “prebiotic” — compounds that promote the growth of probiotics.<\/p>\n On average, the review found, study patients’ depression<\/a> symptoms improved over two to three months. Some trials, however, did not include a comparison group that took inactive supplements<\/a>, to help account for the placebo effect. (That’s the phenomenon in which people feel better simply because they are receiving treatment and believe it will work.)<\/p>\n Another issue is the trials give no clues on which bacterial strains<\/a> might be helpful, according to John Cryan, a professor at University College Cork in Ireland.<\/p>\n
“There is a tendency in the field to ‘lump’ all commercially available strains into the same category independent of the level of evidence there is,” Cryan told the nonprofit Science Media Centre.<\/p>\n But, he added, “we know that strains really matter, and this review is not able to identify what it is about specific strains that render them with beneficial effects.”<\/p>\n Kevin Whelan, a professor at King’s College London, made similar points. “Probiotics often contain different strains of bacteria, and we do not know if the supplements<\/a>, sachets and fermented milks you find on supermarket shelves will work,” he told SMC.<\/p>\n Whelan also stressed that most patients in the trials were taking antidepressants<\/a>.<\/p>\n “So it is crucial that probiotics are seen as complementary to standard treatments recommended by your doctor,” he said, “and not as an alternative.”<\/p>\n <\/p><\/div>\n
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<\/p>\nSLIDESHOW<\/h4>\n
\n Learn to Spot Depression: Symptoms, Warning Signs, Medication<\/span>
\n See Slideshow<\/span>
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