Your Complete Guide to Probiotics

Probiotics may be the new vitamins, but do you really need them? Here are six things to know about these important health boosters. By Holly Corbett, REDBOOK.

What are probiotics anyway?
The microbes or healthy bacteria, which are found in certain foods, live in your gut and help with digestion, regulate metabolism, and boost your immune system. "It's like you have your own Amazon rainforest in your belly," says Elizabeth Lipski, Ph.D, C.N.N., author of Digestive Wellness. "Your gut has three-and-a-half to four-and-a-half pounds of these little bugs, which is about equivalent to the size of your liver." Maintaining a healthy balance of the trillions of these good bacteria in your gut is key for your overall health and wellness.

Why are probiotics so important?
Probiotics play the vital role of helping your body to absorb nutrients from the foods you eat, says says Steven Lamm, MD, "house doctor" on The View and author of No Guts, No Glory. If your balance of healthy bacteria gets out of whack, you'll join the 95-million-plus Americans who suffer from poor digestion - which means experiencing yucky ailments like gas, bloating, and constipation, according to the American College of Gastroenterology. An unhealthy gut may also be the source of seemingly unrelated physical and mental disorders, like diabetes, heart disease, Alzheimer's and mood disorders. Lacking enough friendly bacteria could also make you pack on the pounds, as studies show they help regulate metabolism. In fact, new research published in BMC Microbiology discovered that overweight girls had a different balance of good bacteria in their guts compared to those in the healthy-weight range, and experts think gut bacteria may play a role in obesity.

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How do probiotics work exactly?
While the exact mechanism behind probiotics' superpowers are still unclear, we know they aid with digestion and metabolism by extracting some of the energy from food - especially carbs that haven't been properly digested by the stomach. "The healthy bacteria in your gut also act as foot soldiers for your immune system, eating bad bacteria such as Salmonella and viruses to protect you against foreign invaders," says Dr. Lamm. They even produce vitamins your body needs to stay healthy, such as vitamins K and B6.

What offsets the natural balance of healthy bacteria in our guts?
A poor diet is one of the most common ways to upset the levels of good bacteria. The key to a good one is eating plenty of fruits and vegetables because they contain prebiotics, which healthy bacteria feed off of and need in order to thrive. Insoluble fibers - found in foods such as leeks, garlic, artichokes, oats, and soybeans - are prebiotics. Also look for prebiotics in packaged food ingredients in the form of inulin. Another healthy-bacteria saboteur? Certain meds. "Antibiotics can destroy up to one-third of the healthy bacteria in your system," says Dr. Lamm. Stress, smoking, and alcohol are also friendly bacteria killers.

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Which foods are the best sources of probiotics?
Try eating dairy products such as yogurt (be sure it's not expired or the bacteria are likely to be dead), cottage cheese, and kefir. If you're lactose intolerant, you can still get the good bacteria you need by opting for fermented foods like sauerkraut, barreled pickles (preservatives in the bottled kind kill healthy bacteria), and miso. You may notice probiotics added to unfermented foods at the grocery store, such as coffee and pizza, but avoid marketing hype by buying only products that say "live and active culture" on the label. Also steer clear of foods that need to be heated, since cooking probiotic-rich foods could kill the good bacteria.

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Should I take a supplement?
Yes, according to Dr. Lamm. "The modern diet contains less fermented foods and more cooked and processed foods, so most people aren't getting enough probiotics from their diet alone," he says. Since different strains of bacteria help different health issues, you'll need more than yogurt to do it. For overall wellness, look for brands that contain the strains Lactobacillus (Acidophilius is the most common type of this strain) and Bifidobacterium. Also be sure your supplement supplies at least 1 billion CFUs (or "colony forming units") in a day's serving. One to try is Digest Gold + Probiotics, which combines 1.5 billion CFUs in a day's serving (encapsulated in a special coating that makes them more easily absorbable) with other digestion-boosting enzymes.

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