By now you have at least heard about probiotics and prebiotics. These words can be confusing because they sound the same, but they are very different things and perform different functions for your health.

The body contains thousands of different types of bacteria. Some of them are beneficial and some aren’t, which means you want more of the good bacteria, but even when you manage to do so, how do you keep those good bacteria alive and well?

What are Prebiotics and Probiotics Anyway?

In our digestive tract, we have beneficial bacteria that is sometimes called “gut flora” or “gut microbiota” and sometimes plain old “gut bacteria”. Probiotics are the living, good bacteria that are found in some foods and supplements. They have multiple benefits for good health and we will talk about those benefits in a bit. Prebiotics are the food for bacteria. Typically prebiotics are carbohydrates, usually in the form of fiber. Without enough food (prebiotics) our beneficial bacteria would starve to death!

How Are the Gut Flora Beneficial to Us?

You can think of your digestive system as an old western movie. You need lots of the good guys to fight off the bad guys.

Our digestive tracts also contain bacteria and fungi that can cause our bodies damage. By keeping our bodies full of strong, healthy good bacteria, we can fight back against the fungi and bad bacteria.

The healthy part of our gut bacteria is also responsible for regulating inflammation in the body and for sending important signals to your immune system. Some of the bacteria in your gut make vitamin K and a compound called “short-chain fatty acids”.

The cells that line your colon are fed by these short-chain fatty acids. This encourages your cells to provide a strong barrier that prevents bad bacteria, viruses, and other harmful compounds from invading your digestive tract and can reduce your risk of developing cancer when these cells are strong.

Do Certain Foods Affect Our Gut Bacteria?

Yes, it does. All the food you eat plays a big part in the puzzle that makes up the balance of the good and bad bacteria that lives in our digestive system.

As you might imagine, eating a high sugar or high-fat diet has a negative influence on our gut bacteria. It doesn’t provide the body with prebiotics and allows bad types of bacteria and fungi to grow out of control.

Giving bad bacteria food they like, rather than the prebiotic food the good bacteria like, encourages them to grow faster. Harmful types of bacteria can cause you to absorb more calories from the food you eat, leading to unwanted weight gain.

Which Foods Have Prebiotics?

Many foods contain prebiotics. In fact, you are probably eating prebiotics and don’t know it. Most prebiotics are found in vegetables, fruits, and legumes that contain high levels of plant fiber that the human body cannot digest. Prebiotics, however, find this fiber to be their favorite food source!

Some examples of foods high in prebiotics include:

Oats
Berries (all kinds)
Asparagus
Dandelion greens
Onions
Bananas
Garlic
Leeks
Beans
Peas
Apples (especially the skin)
Barley
Cocoa
Burdock root
Flaxseeds
Wheat bran
Jicama

Apple cider vinegar is also a prebiotic, even though it does not contain fiber. You can also purchase prebiotic powders if you are unable to consume most of the prebiotic foods listed above.

The good bacteria in your gut will turn those prebiotic fibers into a short chain fatty acid (butyrate) which has anti-inflammatory effects inside your colon and provides food to healthy cells.

Which Foods Are Rich in Probiotics?

There are many foods that contain healthy and natural probiotic bacteria. Some of the best probiotic foods include yogurt and kefir. Be sure that your yogurt says it contains live cultures.

Fermented foods are also a great source of probiotics. Fermented foods include kimchi, sauerkraut, kombucha tea, and pickles or other fermented vegetables that have not been pasteurized. Pasteurizing kills the probiotics, so be sure the ones you choose say on the label that they are raw and have not been pasteurized.

Other foods that have healthy probiotics include raw cheeses, miso, green olives, and sourdough bread.

What About Probiotic Supplements?

Probiotic supplements are what the name sounds like; they are pills, capsules, chewable tablets, liquids, even gummy forms that contain live or freeze-dried probiotic bacteria.

While supplements are a popular option, they are not all created equal. There are hundreds of different strains of bacteria and these supplements do not always have the same strains or contain the same number of bacteria.

Some supplements are made so they carry the bacteria all the way to the large intestine where it can be more effective. Some supplements end up having a large number of bacteria killed off by stomach acid.

How Do I Choose the Best Probiotic for Me?

Choosing the best probiotic supplement is an individual choice since it would depend on what area you would like to see improvement in or area where you believe you are having problems.

Let’s look at some of the most common types of probiotics found on the market today:

Lactobacillus Probiotic Strains

L. acidophilus improves skin health, gut function, and vaginal health. Considered one of the best probiotics for women.
L. rhamnosus is good for skin health and for general support of the digestive system.
L. plantarum is known for being a super inflammation fighter and improving irritable bowel syndrome symptoms
L. casei improves gut function and improves chronic fatigue symptoms. Also improves cognitive function.
L. brevis is great for those with diabetes and for combating lactose intolerance.

Bifidobacterium Probiotic Strains

B. lactis works best for improving immunity and supports healthy digestive function
B. longum improves gut motility and boosts brain function
B. bifidum also improves immunity and supports a healthy digestive system
B. breve offers digestive support and has anti-aging compounds, especially for the skin
B. infantis is the first probiotic to form in newborns. Helps to fight digestive track issues in both adults and kids.

Saccharomyces Probiotic Strains

S. boulardii is a good yeast that helps those with irritable bowel syndrome and Crohn’s disease, as well as ulcerative colitis and chronic diarrhea.

There are other strains, but these are the one you will most commonly see in supplements today.

Probiotic Benefits

As you can surmise from the above list, the benefits of taking probiotic supplements are varied and far-reaching.

Most benefits have to do with digestive health and the reduction of inflammation but there are other benefits that probiotics can provide, including:

Weight Loss – Researchers believe certain probiotics can inhibit the absorption of fat, preventing the body from getting calories from it. The best probiotics for weight loss include Lactobacillus fermentum and Lactobacillus amylovorus. One study found that eating probiotic yogurt that contained at least one of these strains caused subjects to lower their body fat by as much as 4% over the 6-week study period.
Probiotics for Women – Women have special needs and probiotic supplements can help women to metabolize hormones better, have improved hormone function, and improve natural resistance against yeast infections and urinary tract infections. Some of the best probiotics for women will include the strains L. acidophilus, L. plantarum, L. rhamnosus, and L. brevis. L. crispatus has been shown in studies to reduce UTI’s by as much as 50%.
Improve Mental Health -Many people don’t know that our gut health and mental health, as well as our moods, are intertwined. A meta-analysis of 15 studies done with human subjects found that the probiotic strains Bifidobacterium longum and B. breve, as well as Lactobacillus helveticas and L. rhamnosus, given over a 6-week period, improved depression, memory, and anxiety levels.
Improve Heart Health – Probiotics have been shown to reduce cholesterol and lower blood pressure levels. Probiotics break down bile, which can prevent it from being reabsorbed as cholesterol.
Antibiotics, while they can save a life, don’t discriminate. They kill both good and bad bacteria. Overuse of antibiotics can actually cause permanent changes in some of our gut bacteria, especially if high doses are given frequently during childhood or early adolescence. Unfortunately, antibiotics are still abused by many people. Researchers are currently studying how this can affect our health later in life and how to restore healthy gut flora.

Which Supplement is Best and How Much Should I take?

Consuming probiotics and prebiotics from food is always a good choice. You can find many live probiotic cultures in fermented foods, some soy products, and fermented dairy products such as yogurt.

Many people find, however, that they simply cannot eat enough of these foods to give them the benefits they are looking for.

This is where probiotic supplements can be very beneficial. Probiotics come in many forms, including tablets, powders, “gummies”, and capsules. These supplements contain live bacteria of one or more strains.

What Are CFU’s and Why Do They Matter?

To get the benefits from probiotics, you need to consume them in large enough numbers, so they can survive storage, stomach acid, and work in the gut as designed. Probiotics are measured in CFU’s or Colony Forming Units. This number represents the actual count of live probiotic bacteria in each capsule (or serving).

If you look at any probiotic supplement bottle, you will see they list anywhere between several million to billions. Most researchers say in order to see any benefit, you need between 10 million to 1 billion CFUs every day.

Studies show that multi-strain probiotic supplements will give you better results than a single strain supplement. When you consider that your gut contains at least 400 different strains of bacteria, because different strains perform different functions, it makes sense to “stock up” on a diverse collection of strains to get the most probiotic health benefits.

If you are interested in improving your health in general, a probiotic supplement should contain at least 2 million CFUs and contain at least two strains (usually Lactobacilli and Bifidobacterium). Read the label to see if the company states what percentage of the bacteria lives and makes it to your intestines.

Can You Overdose on Probiotics?

If your digestive tract is healthy and you take a higher level of CFUs than your body needs, you might have mild side effects, such as

Excessive gas
Bloating
Abdominal pain
Cramps
Tenderness in the abdomen

If you experience these symptoms, stop taking the probiotics for a few days, then try again at a lower dose.

What Is the Best Supplement Form? Are Tablets Better than Gummies?

Capsules. These are the most common form. You might find some probiotics in the refrigerated section and wonder why some need refrigeration, and some don’t. Freeze-dried bacteria, which are becoming more common, do not need to be refrigerated if they are sealed in blister packs or in other sealed containers. Otherwise, they will need refrigeration. Read the label first.
Chewable. They intend these for children, but if you don’t like swallowing pills, chewables are a great alternative.
Liquid. These will be in the refrigerated section since live and active probiotics can become unstable and die in warmer temperatures. These are another great alternative for those who don’t like swallowing pills or for children.
Drinks. Some probiotic “drinks”, such as kefir water or juices containing probiotics, are a popular option but read the labels carefully. Many of these drinks have a limited number of strains and even fewer CFUs than most other supplements.
Powders. This is an easy choice for those who want to add probiotics to whatever they are eating or drinking. You can get picky children, who won’t take pills or chewables, to get their probiotics by mixing the powder in just about anything, including applesauce or fruit juice.
Gummies. The latest form to hit health food stores is probiotic gummies. These supplements taste good, are very children friendly, and promoted as being able to withstand stomach acid, allowing them to reach the intestines where the probiotics will do the most good.

Which form is best? The form of the supplement isn’t as important as the strains it contains and the number of CFUs it has that will survive long enough to make it to the intestines. In most cases, probiotics that list themselves as “delayed-release” are preferred since the capsule or tablet contains a protective outer coating that will prevent stomach acid from killing most of the bacteria.

The Bottom Line

Remember that in order for probiotics to flourish, they need prebiotics. So, besides whatever probiotic you decide to take, be sure you are eating a healthy diet that includes plenty of fiber to feed the probiotic bacteria.

Probiotic supplements come in many forms. Whichever form you choose is not as important as the number of CFUs, the strains, and the percentage of bacteria that will survive the journey to the intestines.

Take care that you store probiotics that contain live cultures in the refrigerator. If the bacteria have been freeze-dried, it won’t need refrigeration. However, probiotic supplements have a shorter expiration date than other supplements, such as vitamins, so take note of the date and store even freeze-dried supplements in a cool, dry, dark location for a longer shelf life.