Can you guess which room in your home contains the most bacteria?
If you guessed the bathroom, guess again. Some of the most bacteria-dense surfaces in your house are your kitchen dish rags, cutting boards and countertops. Most of us actively try to avoid bacteria for good reason. Bacteria like E. coli or salmonella can cause severe gastric problems. However, not all bacteria are harmful to you, and some of the good bacteria are probably already living in your groceries.
Bacteria that aids digestion is known as probiotics. There are hundreds of different strains of probiotics living in your gut that help break down certain types of fiber and support your immune system. Foods that are fermented such as yogurt and sauerkraut are among the foods with the highest amounts of probiotics.
In fact, research shows that these healthy bacteria may even reduce your risk of developing bowel cancer, which is one of the four most common types1 of cancer along with prostate, breast and lung cancer.
Research shows that including prebiotics in your diet may also be beneficial. Prebiotics are essentially food for the healthy bacteria in your gut that like to eat indigestible types of fiber.
Keep reading to find out how you can include more probiotics and prebiotics in your meals and why they might be the missing piece in your dietary puzzle.
A Brief History of Probiotics
It’s thought that the fermentation process was discovered by accident. However, the origin of fermented food goes back nearly 10,000 years2. Legend has it that yogurt was discovered accidentally in the Middle East when people transported bags of milk from regions with low humidity to hotter areas.
Fermenting vegetables has been common practice in China since 300B.C. to increase the shelf life of foods3. Japan has also been fermenting soy products for thousands of years, and kimchi in the Korean peninsula is thought to have originated around the same time. People thousands of years ago understood that the fermentation process could help them store foods longer during extreme weather conditions, but people didn’t know about the health benefits until the last hundred years.
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Elie Metchnikoff is the pioneer of probiotic research. In the early 1900s, he postulated that fermented milk could improve human health4. He also developed a theory that toxic gut bacteria cause aging. Around the same time, in 1905, a Bulgarian scientist named Stamen Grigorov discovered the primary strain of lactic acid bacteria used to produce yogurt that would later be named L. delbrueckii ssp. bulgaricus after his home country5. Elie Metchnikoff took an interest in the relatively long lifespans of peasants in Bulgaria who consumed yogurt regularly. He theorized that it was the bacteria in the yogurt that caused them to live longer than other groups.
In the 1930s, the Japanese doctor Minoru Shirota went on to pose that healthy gut bacteria from eating foods like miso soup could reduce the incidence of gut disease4. Research on probiotics reached a dead end that wouldn’t be revisited seriously until the late 1900s6.
In 1974, researchers coined the first definition of probiotics. They defined probiotics as live organisms that contribute to the host of the gut health of a host animal7. Throughout the 1990s, researchers began finding the potential of probiotics to aid the immune system and ward off disease. By 2007, the global sales of probiotic ingredients and supplements increased to $14.9 billion in the U.S. By 2025, sales are anticipated to reach $71.9 billion7.
Foods That Contain Probiotics
One of the best ways to maintain healthy gut flora is by eating a varied diet. However, the average western diet is anything but diverse. It’s estimated that 75% of the food produced in the world comes from 12 plants and five animals8.
The following fermented foods are amongst the most common that contain gut-healthy probiotics:
- Miso Soup
Two common types of probiotic bacteria with benefits for humans are called Lactobacillus and Bifidobacterium9.
Lactobacilli usually live in your digestive tract, urinary systems and genitals. Research10 shows that they can down-regulate mucosal inflammation through your gut. They also help people with lactose intolerance digest dairy foods.
Bifidobacteria are usually found in your intestines. This type of bacteria ferments oligosaccharide (small chains of sugar). They help break down complex carbs that your body can’t digest itself.
Including bifidobacterial in your diet is associated negatively with obesity and weight gain. Lower levels of this healthy bacteria are associated with inflammation and irritable bowel syndrome11.
Bifidobacterial may help reduce infections from other bacteria such as E. coli12.
Bacteria and Cancer
The human gut contains more than 100 trillion microbial cells which have a variety of functions including aiding vitamin B and K synthesis, metabolizing bile, sterols and xenobiotics and activating your immune system13.
Cancer kills over 600,000 people per year in the United States14. Even though consuming probiotics may decrease your risk of developing cancer, not all bacteria are good for you.
Some bacteria are carcinogenic by nature15. Infection of the bacterium H. pylori increases your risk of developing stomach cancer by increasing cell division16. Unhealthy bacteria can also produce toxins that interfere with your body’s regulation of cellular growth. Some types of bacteria also increase inflammation in your body.
Chronic inflammation is a risk factor in the development of cancer. In fact, research17 shows that more than 20% of cases of cancer development are thought to be caused directly from chronic inflammation.
Obviously, you want to avoid the “bad” bacteria and include more “good” bacteria in your diet.
Research is starting to show that probiotics may have the potential to prevent certain types of cancer and aid in cancer therapy. These healthy bacteria reduce tumors by attacking neoplasms (new and abnormal tissue growths) and starving the cancer cells of nutrients.
Probiotics and Colorectal Cancer
Genetics play a big role in the development of cancer. If somebody in your family was diagnosed with cancer, you’re likely to also develop the same type of cancer. It’s thought that food and lifestyle factors cause 30-40% of cancers and the remainder comes from genetic influences18.
Colorectal cancer is the third most common cancer for men and the second most common cancer in women19.
Most of the research on the benefits of probiotics for cancer is still quite new, meaning animal studies and lab studies.
However, some research on humans is starting to come out20.
The mechanism by which dietary probiotics can prevent colorectal cancer is still not well understood. Some ways it may help fight against cancer include the following21:
- Changing the composition of your intestinal microflora
- Deactivating cancerous compounds
- Competing against harmful microorganisms
- Improving your immune system
- Fermenting undigested foods
- Inhibiting tyrosine kinase pathways
Your immune system releases a group of proteins called cytokines in response to various types of stress including infection, inflammation and carcinogenic growths. Their purpose is to try to minimize cellular damage.
Research shows that a mix of the strains Bifidobacterium spp and lactobacillus can increase the secretion of cytokines that reduce inflammation and up-regulate several genes that can decrease tumor development22.
Most of the research on the effects of probiotics on cancer isn’t easily digestible unless you have a biochemistry or genetics degree.
For example, the probiotic Bacillus polyfermenticus, which is often used in Eastern Asia to prevent gastrointestinal issues, suppresses the expression of the genes ErbB2 and ErbB3. This gene suppression lowers your risk of tumor development.
You don’t need to memorize the esoteric details. The following are the takeaway points you should be aware of:
- Most of the research on probiotics has been animal and lab studies
- Research shows that probiotics likely reduce colorectal cancer risk
- It’s not well understood how probiotics prevent cancer
Probiotics in Cancer Therapy
Chemotherapy treatments often cause side effects like nausea, vomiting, loss of appetite and diarrhea. Probiotics treat toxicity in the bowel caused by chemotherapy.
Taking probiotics while undergoing cancer therapy may help keep a healthy microbial balance in the gut, which alleviates some of the gastrointestinal problems caused by cancer treatment.
In a study published in the World Journal of Surgery, researchers examined the effects of probiotic supplements on the rate of healing from colorectal cancer surgery. An intervention group was given daily capsules containing the probiotics Lactobacillus acidophilus, L. plantarum, Bifidobacterium lactis and Saccharomyces boulardii for 15 days after colon surgery.
The researchers23 found that the intervention group had a significantly decreased risk of postoperative complications compared to people who did not consume probiotics.
However, it’s worth noting that patients with suppressed immune systems may be vulnerable to bacteria related diseases such as sepsis13. Patients with suppressed immune systems, should exercise caution when taking probiotics and take them under a doctor’s supervision.
Probiotics May Lower Risk of Developing Cervical Cancer
Early research suggests that probiotics may also reduce your risk of developing cervical cancer and may alleviate the side effects of radiotherapy post-treatment.
In a pilot study published in the European Journal of Cancer Prevention24, researchers examined the effect of drinking a probiotic drink daily for the six months following diagnoses with human papillomavirus-related cervical lesions.
The study found that the intervention group consuming the probiotic drink showed higher clearance of the cervical abnormalities.
In another study, researchers looked at the effect of consuming a probiotic supplement consisting of Lactobacillus acidophilus LA-5 and Bifidobacterium animalis subsp. lactis BB-12 on gastrointestinal effects of radiotherapy. The researchers divided 54 patients into an intervention group and a placebo group.
The probiotic group had significantly reduced symptoms of diarrhea and reduced abdominal pain.
Benefits of Probiotics for Gastrointestinal Problems
Research13 shows that probiotics can help with several gastrointestinal disorders including lactose intolerance, inflammatory bowel disease and irritable bowel syndrome.
Lactose intolerance is caused by a genetic deficiency in the enzymes that breakdown lactose into the sugars glucose and galactose.
It usually causes symptoms of gastric distress including diarrhea, abdominal pain and gas. Studies25 show that including yogurts with the specific strains of bacteria S. thermophilus and L. delbrueckii ssp. Bulgaricus may improve lactose metabolism.
Prebiotics: The Food for Your Food
We’ve discussed the benefits of probiotics at length, but there’s another biotic you should be aware of: prebiotics.
The definition of prebiotic has undergone several changes since they were first defined in 1995. The best current definition would be an indigestible compound metabolized by the microorganisms in the gut of an animal that benefits the animal11.
Essentially, including prebiotics allows more healthy bacteria to grow in your gut.
Prebiotics provide healthy bacteria with food. Including prebiotics in your diet is kind of like feeding pigeons in the park. At first, there might be three or four pigeons pecking at your feet, but once you start throwing bread crumbs on the ground, every pigeon in the state is flocking towards you.
One of the main types of prebiotics is called inulin. Inulin is a soluble form of fiber found in a wide variety of plant foods. It’s made up of chains of fructose molecules arranged in a way that your body can’t digest.
Research11 shows that including prebiotic food in your diet can do the following:
- Increase the amount of Bifidobacteria and Lactobacilli in your gut
- Increase your calcium absorption
- Decrease protein fermentation
- Decrease allergy symptoms
- Improve gut health
- Improve your immune system
Like most of the research on probiotics, many of the studies on prebiotics are lab and animal studies. However, early research26 shows that prebiotics may also help reduce cancer risk.
A literature review published in the British Journal of Nutrition27 reviewed 12 animal studies that found that prebiotic consumption was linked to reductions in precancerous colon growths.
Here is a list of foods high in prebiotics:
- Chicory Root
- Dandelion Greens
Potential Benefits of Polyphenols for Healthy Bacteria
Polyphenols are a group of bioactive compounds that benefit human health and metabolism28 Research29 shows that dietary polyphenols help with the maintenance of healthy bacteria in your gut.
Here are some foods that are high in polyphenols.
- Dark Chocolate
- Celery Seeds
- Star Anise
- Cocoa Powder
Your Useless Appendix
The appendix is most well known as a useless organ that often gets infected. However, some scientists argue that it may serve a function after all.
One theory is that the appendix is a storage vessel for good bacteria.
If you have a bacterial infection that causes gastrointestinal problems such as diarrhea, a lot of your good bacteria get wiped out. However, some researchers30 believe some of your good bacteria can hide out in your appendix until the infection passes.
For now, it’s still just a theory, but it’s at least an interesting thought. People with their appendix removed do seem to have slightly higher rates of infection.
How to Optimize Your Gut Bacteria
Including bacteria in your diet doesn’t give you permission to eat the Chinese take-out that’s been in your refrigerator for the past six weeks. There are millions of types of bacteria, and only a few types are good for you.
1. Eat Fermented Foods
If you want to benefit from the anti-carcinogen effects of probiotics, you should make an effort to make fermented foods a regular part of your diet. You can either buy fermented foods at the grocery store to include more healthy gut bacteria in your diet or you can make them on your own.
2. Make Your Own Yogurt Culture
Fermented foods such as yogurt are very simple to make yourself — if people 10,000 years ago can accidentally make it, how hard could it be?
All you need to start a yogurt culture is a few spoonfuls of yogurt and milk. Heat the milk over the stove until it almost reaches boiling and cool to 112-115 degrees. Add about three tablespoons of yogurt and incubate overnight in your oven.
3. Eat Prebiotic-Rich Foods to Feed Probiotic Bacteria
As well as including probiotics in your diet, you can also eat foods that support the health of the healthy bacteria in your gut. Make sure to include prebiotic foods in your diet as well to maintain the health of these bacteria.
If you’re already eating a diet high in fruits and vegetables, you’re likely already getting plenty of prebiotics.
4. Eat Polyphenol-Rich Foods to Support Probiotic Health
Do you go weak at the knees when you smell chocolate? Including dark chocolate and other polyphenol-rich foods in your diet can also support healthy bacteria in your gut.
5. Supplement With Floracil 50 and ACV+ Prebiotics
No one food can prevent the development of cancer, but including the right foods in your diet can lower your risk.
People have been including probiotics in their diets for thousands of years for good reason, whether they knew it or not. The human gut is incredibly complicated, and there’s still a lot we don’t know about it. Hopefully, in the next few years, more research on probiotics becomes available so we can continue to improve our understanding about how these healthy microbes benefit us.
Our probiotic formula, Floracil 50, is designed with eight hand-picked probiotic strains backed by 41 research studies to ensure each strain has its own unique way of strengthening your digestion and immune system. We include 50 billion CFUs (“Colony Forming Units”) at time of manufacturing so you know you’re getting the ideal amount of probiotics backed by the research studies every day.
Nourish your healthy gut bacteria with our Apple Cider Vinegar and Prebiotics supplement. It feeds your healthy bacteria with essential prebiotic fibers and apple cider vinegar to help your “good bacteria” thrive in your gut while getting rid of “bad bacteria” safely and naturally.
- Healthy Bacteria Regulation
- Cut Down on Bloating
- Clean Your Gut
- Hunger Regulation
- Improve Gut Wall Permeability
- Boost Your Immune System
Citations and Sources
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