So, What the Heck is a Probiotic?

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As a Registered Dietitian, I keep a pretty close watch on nutrition and supplement trends. A recent hot topic – and something you’ve likely seen popping up all over grocery stores and online -- is probiotics. But what the heck are probiotics, anyway? And why should you care about them?

Well, I’ll tell you.

Probiotics are living organisms, like bacteria or yeast, that are believed to improve health. The body is a natural home to these organisms; the digestive system alone boasts a large quantity of many types of bacteria, which help keep the intestines healthy and aid in digesting food. These healthy bacteria also help to protect us from pathogens (harmful bacteria), to detoxify harmful compounds (like alcohol or drugs), and more.

Normally, our body has a healthy plethora of gut microorganisms, but sometimes, due to reasons like stress, intestinal damage, infection, excessive antibiotic use, or poor diet (not enough fruits/veggies), the bacterial ratio can become imbalanced. This can lead to a host of issues involving our immunity, and can also cause gastrointestinal (GI) problems like gas, bloating, and diarrhea, along with poor nutrient absorption.

Historically, most of our probiotics came from one of two sources: dirt or food. But as the world becomes cleaner, antibacterial products boom, diets decrease in quality and food is more likely to be pasteurized, it can be harder to get probiotics naturally.

Food-based sources of probiotics include foods and beverages that have been fermented, but not pasteurized, as pasteurization kills bacteria. Before you get too excited -- no, beer and wine do not have probiotics. Unfortunately, they are filtered out during processing! And neither does sourdough bread -- the bacteria are destroyed during baking.
When probiotics are present in a product/food, you’ll see them noted in the ingredients list by name, such as ‘L. Acidophilus’ or ‘B. Bifidum.’ Here are some examples of common foods that naturally contain probiotics:

  • Yogurt: Look for “live, active cultures” on the label, and choose brands with short, simple ingredient lists (no gums, corn starch, artificial sweeteners, or other additives that you don’t understand). I like plain Greek yogurt, which is high in protein with no added sugar (just some naturally occurring sugar from the milk), paired with fresh fruit and nuts or seeds.
  • Buttermilk: Probiotics are added to milk to ferment the sugars, making buttermilk -- but beware: they will be destroyed if the buttermilk is heated or cooked.
  • Kefir: Made by fermenting milk with yeast and bacteria, kefir is sort of like a drinkable yogurt, although it has different strains (types) of probiotics than yogurt. Try it in place of milk over cereal or in smoothies.
  • Kombucha: Made by fermenting yeast and bacteria with sweetened tea, this slightly carbonated beverage is rich in probiotics, but can be an acquired taste. You’ll find it in the refrigerated section of the grocery store.
  • Sauerkraut: Not all mass-produced sauerkraut contains probiotics (some are heat treated, which destroys the live cultures), so look for one that is refrigerated and labeled as ‘containing live cultures.’ Or, make your own at home!

If you’re healthy and eat non-pasteurized fermented foods at least a few times a week, you likely are doing just fine on the probiotic front. But if you’re not, or if you’ve been experiencing a lot of stress, taking antibiotics, or having GI issues, it might be worth it for you to consider taking a probiotics supplement.

That said, there are a few things you should know before taking a probiotics supplement:

  1. Probiotics may not be safe for everyone.
If you have a weakened immune system (such as that caused by chemotherapy), have had most of your GI tract removed, or have any other serious medical conditions, talk to your doctor before taking probiotics.
  • GI symptoms may worsen in the short term.
  • If you have extreme
    , ramping up the probiotics too quickly may lead to some unpleasant side effects, like a short lived possible worsening of the GI symptoms you already have. Consult your doctor if you have concerns or side effects that last more than a couple days.
  • Probiotics are not regulated like drugs.
  • They are generally considered safe, but do not require FDA approval before marketing, so look for a product that has scientific support to back up the claims they are making. There is also no standardized or generally recommended amount or type of microbes required in supplements (or foods labeled as containing probiotics, for that matter). That said, supplements normally contain doses in the billions; microbe counts are usually listed as colony-forming units (CFU), which are the number of live organisms in a single dose.
  • Read product labels.
  • Be sure to follow instructions on dosage and frequency, and note the expiration date and any storage instructions (like refrigeration) to minimize the risk of the probiotics losing their potency. Products should guarantee the presence of active cultures through the expiration date – not just at time of manufacture.

    In terms of which specific strain of probiotics you should take, the answer is complicated and depends on many factors. Each person has a unique set of microbes and may respond differently to probiotics. However, there are a few common strains to keep an eye out for. Lactobacillus Acidophilus (abbreviated L. acidophilus) is the most popular strain of probiotic, and research has shown it can enhance your immune system and help to reduce Candida (a form of yeast) overgrowth. Bifidobacteria Bifidum (abbreviated B. bifidum) is another common strain; this one aids in digestion, supports the immune system, and helps with the synthesis of B vitamins. The most researched strain is ‘Lactobacillus rhamnosus GG’ (abbreviated L. rhamnosus or Lactobacillus GG), which has been shown in studies to help prevent and treat diarrhea, to reduce risk of respiratory tract infections and more.

    Bottom line: taking probiotic supplements requires a bit of trial and error. If you think you would benefit from a probiotic supplement, look for one made by a reputable company that has been tested for the effects that you are interested in. If it works, great. If not, consider trying another one with different strains.

    Culturelle Probiotic is the only probiotic brand with 100% Lactobacillus GG -- a unique strain of probiotic that’s naturally sourced and is clinically proven to restore balance in the digestive tract, to help your digestive system to work better and support your immune system.*