What are probiotics?

Probiotics are a combination of live beneficial bacteria and/or yeasts that naturally live in your body. Bacteria is usually viewed in a negative light as something that makes you sick. However, you have two kinds of bacteria constantly in and on your body — good bacteria and bad bacteria. Probiotics are made up of good bacteria that helps keep your body healthy and working well. This good bacteria helps you in many ways, including fighting off bad bacteria when you have too much of it, helping you feel better.

Probiotics are part of a larger picture concerning bacteria and your body — your microbiome. Think of a microbiome as a diverse community of organisms, such as a forest, that work together to keep your body healthy. This community is made up of things called microbes. You have trillions of microbes on and in your body. These microbes are a combination of:

  • Bacteria.
  • Fungi (including yeasts).
  • Viruses.
  • Protozoa.

Everyone’s microbiome is unique. No two people have the same microbial cells — even twins are different.

For a microbe to be called a probiotic, it must have several characteristics. These include being able to:

  • Be isolated from a human.
  • Survive in your intestine after ingestion (being eaten).
  • Have a proven benefit to you.
  • Be safely consumed.

Where do beneficial probiotics (microbes) live in my body?

Though the most common place linked to beneficial microbes is your gut (mostly large intestines), you have several locations in and on your body that host good microbes. These locations are in contact with the “outside world" and include your:

  • Gut.
  • Mouth.
  • Vagina.
  • Urinary tract.
  • Skin.
  • Lungs.

How do probiotics work?

The main job of probiotics, or good bacteria, is to maintain a healthy balance in your body. Think of it as keeping your body in neutral. When you are sick, bad bacteria enters your body and increases in number. This knocks your body out of balance. Good bacteria works to fight off the bad bacteria and restore the balance within your body, making you feel better.

Good bacteria keeps you healthy by supporting your immune function and controlling inflammation. Certain types of good bacteria can also:

  • Help your body digest food.
  • Keep bad bacteria from getting out of control and making you sick.
  • Create vitamins.
  • Help support the cells that line your gut to prevent bad bacteria that you may have consumed (through food or drinks) from entering your blood.
  • Breakdown and absorb medications.

This balancing act is naturally happening in your body all of the time. You don’t actually need to take probiotic supplements to make it happen. Good bacteria is just a natural part of your body. Eating a well-balanced diet rich in fiber every day helps to keep the number of good bacteria at proper levels.

What are the most common types of probiotic bacteria?

Though there are many types of bacteria that can be considered probiotics, there are two specific types of bacteria that are common probiotics found in stores. These include:

  • Lactobacillus.
  • Bifidobacterium.

Probiotics are also made up of good yeast. The most common type of yeast found in probiotics is:

  • Saccharomyces boulardii.

Can I use probiotics to help with medical conditions?

There is currently a large amount of research happening around the idea of what probiotics can do for your body. Even though there are a lot of possibly positive outcomes, researchers are still working to find definitive answers about how probiotics can help with various conditions.

However, there are some medical conditions where probiotics may help. This can vary between people meaning that what works for one person may not work for another. These can also vary based on the certain probiotic that is taken.

Some of the conditions that might be helped by increasing the amount of probiotics in your body (through food or supplements) include:

Can I take or eat something to increase the good probiotics (microbes) in my body?

You can increase the amount of good microbes in your body through foods, drinks and supplements. You may already have certain foods in your daily diet that contain probiotics. Fermented foods in particular (yogurt and pickles, for example) are home to a host of good bacteria that benefit your body. There are also fermented drinks like kombucha (fermented tea) or kefir (fermented dairy drink) that introduce extra probiotics into your diet.

Apart from food, you can add probiotics to your diet through dietary supplements. These aren’t drugs, so they do not need to be approved by the Federal Drug Administration (FDA). It’s important that you always talk to your healthcare provider before starting any kind of supplement or major change to your diet.

Can I get probiotics from food?

You can absolutely increase beneficial microbes in your body from the foods you eat. Certain foods have probiotics (good bacteria) in them and can benefit the health of your microbiome.

These foods can be introduced into your diet at any point of the day. You may even be regularly eating them now and not realize that they contain probiotics. You will want to check the food label for “live and active cultures.” A few suggestions for just some of the probiotic-rich foods you can add to your diet and some times to try them include:

For breakfast, try:

  • Yogurt.
  • Buttermilk.
  • Sourdough bread.

For lunch, try:

  • Cottage cheese.
  • Kombucha.
  • Tempeh.

For a snack, try:

  • Fermented pickles.

For dinner, try:

  • Fermented sauerkraut.
  • Kimchi.
  • Miso soup.

Make sure you are still creating a balanced and healthy meal each time you sit down to eat. Though adding probiotic-rich foods into your diet won’t hurt you, balance is still key. Adding too much of just one food prevents your body from reaping the benefits of other food groups.

How do I take a probiotic supplement?

There are several ways you can take a probiotic supplement. They come in a variety of forms, including in:

  • Foods.
  • Drinks.
  • Capsules or pills.
  • Powders.
  • Liquids.

Probiotic supplements may be combined with a prebiotic. Prebiotics are complex carbohydrates that feed the microorganisms in your gut. Basically, prebiotics are the “food source” for the good bacteria. They help feed the good bacteria and keep it healthy. Prebiotics include insulin, pectin and resistant starches.

When you have a supplement that combines a probiotic and prebiotic, it’s called a synbiotic.

How effective are probiotics?

Researchers are currently unsure how effective probiotic supplements are for treating conditions. There’s constant research on the topic. While many research studies have had positive results on the impact of probiotic supplements, more research is still needed.

It’s also important to keep in mind that unlike medications, dietary supplements do not need to be approved by the FDA. This means that manufacturers can sell supplements simply with “claims” of safety and effectiveness.

Always talk with your healthcare provider (or pediatrician) before taking a supplement or giving one to your child. Supplements might interfere with medicines you may be taking. If you are pregnant or breast feeding, check with your provider before taking any supplement.

Are there any storage instructions for probiotics?

Several probiotic strains are very fragile and need to be protected from heat, oxygen, light and humidity. The probiotics might start to break down or die if they are exposed to these elements. Because of this, you may need to refrigerate your probiotics or store it in a particular place. Refrigerating certain probiotic strains ensures that they’re still viable when you go to use them and will still provide the full benefit of the probiotic. Always read the labels on any probiotic product you purchase to make sure you store it correctly and use it within the expiration date.

How safe are probiotics?

Because microbes used as probiotics already exist naturally in your body, probiotic foods and supplements are generally considered safe. They may trigger allergic reactions, and may also cause mild stomach upset, diarrhea, or flatulence (passing gas) and bloating for the first few days after starting to take them.

There are certain people who need to use caution when using probiotic supplements. There is a risk of infection in some people. These people include those who have:

  • A weakened immune system (those going through chemotherapy for example).
  • A critical illness.
  • Recently had surgery.

Caution should also be used when giving probiotics to very sick infants.

Always talk to your healthcare provider before starting a probiotic supplement.

Can probiotics hurt me?

For most healthy people, probiotics don’t cause any harm. They are generally considered safe and are often “given a try” to see if they could help with various medical conditions. There’s a lot of research around the topic of probiotics. Scientists are trying to determine when and how they should be used, as well as how effective they are. Talk to your healthcare provider before starting a probiotic supplement because there are some cases where you shouldn’t be taking them. It’s always best to have the conversation first before starting a new supplement.

Probiotics are generally considered safe. However, there are some risks linked to the supplements. These risks are increased if you have a medical condition that weakens your immune system, have recently had surgery or have other serious medical conditions.

Unlikely, but possible, risks can include:

  • Developing an infection.
  • Developing a resistance to antibiotics.
  • Developing harmful byproducts from the probiotic supplement.

Should I give probiotics to my kids?

Introducing probiotics into your child’s diet through food is a safe way to give them probiotics. Foods like yogurt are often a part of a balanced diet and can add in that good bacteria without much risk. It’s best to talk to your child’s healthcare provider (pediatrician) before giving your child a supplement. There are commercially available probiotic supplements specifically designed for infants and children.

Do I need to take probiotics after I take antibiotics?

Antibiotic medications are often needed to fight an infection. However, while antibiotics are killing the bad bacteria, they are also knocking out the good bacteria in your body. Some people develop conditions like diarrhea after taking an antibiotic. In other people, this may allow for really bad bacteria to take over and populate the gut, such as with C. diff. Some research has shown a positive connection between taking probiotics after an antibiotic and relief from diarrhea. This hasn’t been proven yet and doesn’t work for everyone.

The thought behind adding probiotics back into your body after taking an antibiotic is that it can repopulate the good bacteria that was destroyed by the antibiotics and re-boot your system. The extra good bacteria helps repopulate your gut and fight off any remaining bad bacteria. Many people feel that adding in probiotics won’t hurt, might help you feel better a little faster and prevent diarrhea.

Should I try probiotics?

If you are interested in adding probiotics to your diet, it’s worth a conversation with your healthcare provider. Many providers may suggest giving them a try to see if they help with your general health. It is important to remember that not all probiotics behave the same way and have the same effects. Each has their own individual benefits. They generally don’t cause harm. One easy way to start can be by simply introducing probiotic-rich foods into your diet, like yogurt.

Before you start any supplements, make sure you talk to your healthcare provider. Your provider may be able to point you in the right direction, helping you figure out the best probiotic to take, how much to take and when to take it. A conversation is always worth the time when it concerns your health.

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