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7 Reasons to Get Prebiotics in Your Diet — Plus the Best Sources
January 2, 2023
By now, most people are well-aware that foods rich in dietary fiber and probiotics offer a long list of benefits and are essential to overall health. Nonetheless, prebiotics are still largely under-appreciated and often lacking in the typical American diet.
Unfortunately, this can result in serious issues like indigestion, inflammation, impaired immunity, weight gain and possibly even an increased risk for many chronic conditions.
Are prebiotics better than probiotics? Ideally you should get both. While probiotic foods play a key role in gut health and overall well-being, prebiotics help “feed” the probiotics to bump up the health benefits even more.
As explained more below, prebiotics and probiotics together amplify the incredible health-promoting properties of these powerful ingredients.
What Are Prebiotics?
By definition, prebiotics are non-digestible fiber compounds that are degraded by gut microbiota.
What do prebiotics do? Just like other high-fiber foods, prebiotic compounds pass through the upper part of the gastrointestinal tract and remain undigested because the human body can’t fully break them down. Once they pass through the small intestine, they reach the colon, where they’re fermented by the gut microflora.
Today, when researchers refer to “fiber,” they’re speaking about not just one substance, but a whole group of different chemical compounds found in foods. According to a 2018 article published in Current Developments in Nutrition, prebiotics are best known as types of dietary fibers called fructooligosaccharides, inulin and galactooligosaccharides.
Originally, prebiotics weren’t classified as prebiotic fiber compounds, but recent research has shown us that these compounds behave the same way as other forms of fiber. Today, prebiotic carbohydrates that have been evaluated in humans largely consist of fructans and galactans, both of which are fermented by anaerobic bacteria in the large intestine.
Certain foods function as natural prebiotics. Some examples of foods high in prebiotics include chicory root, dandelion greens, leeks and garlic.
What are the benefits of prebiotics? Upping your intake of prebiotics has been linked in studies to a long list of powerful benefits, including lower risk for cardiovascular disease, better gut health, lower stress response. better hormonal balance, higher immune function, lower risk for weight gain and lower inflammation.
Prebiotics vs. Probiotics vs. Postbiotics
What is the difference between prebiotics and probiotics? Prebiotics are substances that are fermented by the beneficial bacteria in the gut and used as a source of fuel to help enhance gut flora health. Probiotics, on the other hand, are defined live microorganisms that can confer health benefits to the host, ranging from improved immunity to better brain function.
Postbiotics, meanwhile, are the byproducts of bacterial fermentation in the colon. To break down all the scientific jargon and put it simply:
Prebiotics “feed” the probiotics, or beneficial bacteria in your gut, and end up producing a byproduct called postbiotics.
When it comes to supplementing, which is best: probiotics or prebiotics?
All three (pre, pro and postbiotics) boast an extensive array of health benefits and work together to boost both digestive and overall health. One is not necessarily “best,” since they work together to optimize things like nutrient absorption, appetite control, immune function, etc.
How They Work with Probiotics to Improve Health
While probiotic benefits have become more widely known in recent years, especially with the growing popularity of fermented foods like sauerkraut, kombucha and kimchi, prebiotics still remain under the radar. All types of fiber that we get from eating whole, plant foods play a major role in nutrient absorption, gut and digestive health.
Can you take prebiotics and probiotics together?
Yes, and you should. Prebiotics, together with probiotics, open the door for heightened levels of health in general, so nearly everyone can afford to include them in their diets more often.
As prebiotics make their way through the stomach without being broken down by either gastric acids or digestive enzymes, they bring about positive changes in the digestive tract and organs. Essentially, prebiotic compounds become nutrient sources, or “fuel,” for the beneficial bacteria housed within your gut.
Prebiotics work together with probiotics (selectively fermented ingredients that produce gut-friendly bacteria) to allow specific changes to take place, both in the composition and activity of the gastrointestinal system. They play a fundamental role in preserving health by maintaining balance and diversity of intestinal bacteria, especially by increasing the presence of “good bacteria,” such as Lactobacilli and Bifidobacteria.
Because the health of the gut is closely tied to many other bodily functions, prebiotics and probiotics together are important for battling inflammation and lowering overall disease risk.
1. Better Gut Health and Improved Digestion
Prebiotics work to stimulate the growth of beneficial bacteria that colonize our gut microflora. Since they act like food for probiotics, prebiotic compounds help balance harmful bacteria and toxins living in the digestive tract.
This has numerous health implications, including improving digestion. Research shows that higher intakes of prebiotics foods can increase numerous probiotic microorganisms, including Lactobacillus rhamnosus GG, L. reuteri, bifidobacteria, and certain strains of L. casei or the L. acidophilus-group.
The beneficial bacteria in your gut uses the indigestible fiber content from the foods that you eat as a source for their own survival. As your gut bacteria metabolize otherwise non-digestible fibers from foods, they produce short-chain fatty acids, which are compounds that boast a wide range of benefits.
One of these beneficial fatty acids is called butyric acid, which improves the health of the intestinal lining. Studies suggest that short-chain fatty acids also help regulate electrolyte levels in the body to promote proper digestion, support regularity, and relieve digestive issues like diarrhea and constipation.
Changes in the gut microbiota composition are classically considered as one of the many factors involved in the development of either inflammatory bowel disease or irritable bowel syndrome. A 2012 report published in the Journal of Nutrition reported that prebiotics, along with probiotics, can help treat many digestive problems, including:
- diarrhea (especially after taking antibiotics)
- certain intestinal infections and chronic disorders, like Crohn’s disease and ulcerative colitis
- symptoms of irritable bowel syndrome (IBS)
- inflammatory bowel disease
- leaky gut
2. Enhanced Immune Function
Many human studies have demonstrated that consuming prebiotic foods can result in significant changes in the composition of the gut microbiome that help improve immunity. This “prebiotic effect” has been associated with improvements in biomarkers and activities of the immune system, including reduced levels of certain cancer-promoting enzymes and bacterial metabolites in the gut.
According to a report in the British Journal of Nutrition, prebiotics can help improve poop frequency and consistency, reduce the risk of gastroenteritis and infections, enhance overall health, and decrease the incidence allergy symptoms. Prebiotics and probiotics also help boost immunity by improving nutrient absorption and lowering the pH in the gut to block the growth of potential pathogens and harmful bacteria.
Prebiotics may help enhance immunity by providing fuel for your gut bacteria. This could be beneficial in the treatment of a wide range of conditions, including viral infections, allergies, eczema and intestinal disorders.
Plus, some studies have even reported a reduction in the incidence of tumors and cancer cells after eating foods high in prebiotics.
3. Lower Inflammation
Prebiotics can help lower inflammation, which is believed to be one of the root causes of many chronic diseases, including our nation’s No. 1 killer: heart disease. In fact, people consuming more prebiotics and fiber tend to have healthier cholesterol levels and lower risk markers for cardiovascular diseases.
Inflammation is also thought to contribute to many other chronic conditions as well, including diabetes, cancer and even obesity. Interestingly enough, it’s believed that prebiotics and probiotics contribute to improvements in metabolic processes that are tied to both obesity and type 2 diabetes.
Research also shows that a healthier gut environment can turn off autoimmune reactions, help the body metabolize nutrients more efficiently, and modulate immune functions that control how and where the body stores fats (including in the arteries).
4. Reduced Risk of Heart Disease
There’s evidence that consuming foods high in prebiotics can reduce glycation, which increases free radicals, triggers inflammation and lowers insulin resistance, all of which can contribute to heart disease.
Prebiotics have cholesterol-lowering properties, which can aid in the prevention of heart disease as well as autoimmune disorders like arthritis. They can also balance the body’s electrolyte and mineral levels, including potassium and sodium, which are responsible for controlling blood pressure.
5. Aid in Weight Loss
Do prebiotics help with weight loss? Recent data from both human and animal studies suggest there’s a connection between taking prebiotics and weight loss. Research notes there are beneficial effects of particular prebiotics on energy homeostasis and potentially increased weight loss.
Higher intakes of all types of fiber are, in fact, linked to lower body weight and protection against obesity.
A 2002 animal study published in the British Journal of Nutrition found that prebiotic foods promote a feeling of fullness, prevent obesity and spur weight loss. Their effects on hormone levels are related to appetite regulation, with studies showing that animals given prebiotics produce less ghrelin, which is the the hormone responsible for stimulating hunger.
6. Protect Bone Health
A 2007 study published in the Journal of Nutrition found that prebiotics enhance the absorption of minerals in the body, including magnesium, possibly iron and calcium. All of these are crucial for retaining strong bone bones and preventing fractures or osteoporosis.
In one study, just eight grams of prebiotics a day was shown to have a big effect on the uptake of calcium in the body that led to an increase in bone density.
7. Regulate Hormone Levels and Mood
Research regarding the “gut-brain connection” is still in its infancy, but it’s becoming clear that mood-related disorders like anxiety or depression are closely linked to gut health. Research suggests that your mood and hormonal balance are affected by a combination of factors that most definitely includes the state of the bacterial inhabitants living inside of your body.
Your gut helps absorb and metabolize nutrients from the foods you eat that ultimately are used to support neurotransmitter functions that create the hormones (like serotonin) that control your mood and help relieve stress.
The final straw in triggering a mood-related disorder might be a series of misfiring neurotransmitters in parts of the brain that control fear and other emotions. These transmissions partly depend on the health of the human microbiome, so when the balance of gut bacteria isn’t working right, other biological pathways, including hormonal, immunological or neuronal, won’t work right either.
Recent studies have demonstrated that prebiotics have significant neurobiological effects in the human brain, including lowering cortisol levels and the body’s stress response.
For example, a 2015 study published in Psychopharmacology explored the effects of two prebiotics on the secretion of the stress hormone cortisol and emotional processing in healthy adult volunteers. After volunteers received one of two prebiotics or a placebo daily for three weeks, the group receiving prebiotics showed positive changes in levels of cortisol, suggesting that it may be beneficial in the treatment of stress-related disorders.
Risks, Side Effects and Interactions
Are prebiotics safe? Yes, but because prebiotics are fermented in the gut, increasing your intake of prebiotics too quickly may lead to some side effects. Possible prebiotic side effects can include abdominal pain, gas, bloating and diarrhea.
Starting with a small amount and increasing gradually is the best way to assess your tolerance and sidestep negative symptoms. If you have IBS, SIBO (small intestinal bacterial overgrowth) or FODMAPs intolerance, then be careful about consuming lots of prebiotics, since this may trigger symptoms.
Additionally, be sure to increase your water intake as well. Fiber-rich foods like prebiotics can absorb water in the colon, which can slow down digestion and cause adverse side effects like dehydration.
Staying well-hydrated while eating plenty of prebiotics can help prevent constipation and promote regularity to keep your digestive tract running smoothly.
Are prebiotics for kids safe?
Generally speaking, prebiotics and probiotics are safe for kids, unless your child has a compromised immune system, cancer or is a premature infant. Some experts believe that for children, it’s generally better to get probiotics and prebiotics through foods instead of supplements.
Some studies have found that eating fibrous foods helps children regulate their appetite and lowers risk for obesity. If you’re unsure of whether your child can tolerate these types of supplements, when in doubt talk to your family’s pediatrician.
Are prebiotics for dogs and pets safe?
Yes, according to the Whole Dog Journal:
Dogs fed prebiotics are less likely to get diarrhea caused by the overgrowth of bad bacteria, and soluble fiber also helps to prevent or treat diarrhea by absorbing water and slowing intestinal transit… Prebiotics may be especially beneficial for dogs with immunosuppression or digestive disorders, and for all dogs following antibiotic therapy.
Some commercial dog foods have added prebiotics and sources of soluble fiber, such as chicory root, for example. It’s important that dogs drink enough water when taking prebiotic/fiber supplements, and be careful not to give your pet too much since this can lead to a number of digestive issues.
What foods are prebiotics? While probiotics are typically found in cultured and fermented foods like yogurt, kefir, kimchi and kombucha, prebiotics are typically found in certain vegetables (especially when eaten raw), whole grains and sources of resistant starch, such as under-ripe bananas.
A few of the best prebiotic foods that you can add to your diet include:
- Acacia gum (or gum arabic)
- Raw chicory root
- Raw Jerusalem artichoke
- Raw dandelion greens
- Raw garlic
- Raw leeks
- Raw or cooked onions
- Raw jicama
- Raw asparagus
- Under-ripe bananas
- Yacon syrup
Some other sources include apples with skin, foods that contain isolated carbohydrates (oligosaccharides such as galactooligosaccharides and transgalactooligosaccharides), such as raw honey, wheat dextrin, psyllium husk, whole-grain wheat, barley, oatmeal and whole-grain corn.
Is raw apple cider vinegar a prebiotic? Certain studies show that vinegar may help inhibit enzymes that help with digestion of starches, leading to less of a blood sugar response when eating a high-glycemic meal. Undigested starch may also have a prebiotic effect in the gut because it helps probiotics to thrive.
This means apple cider vinegar can promote the effects of prebiotics, although it is not generally considered a prebiotic itself.
Need a few more ideas to help bump up your intake of prebiotics? Here are some tips to help you reap the rewards of these super healthy ingredients:
- One of the most realistic and delicious ways to prebiotics to your meals is by including nutrition-packed onions. Onions nutrition, both cooked or raw, give plenty of flavor to your food and also provide immune-enhancing antioxidants. They contain a natural source of inulin, one type of good bacteria that fights indigestion. Use onions in savory dishes like sauces, salads, dips and soups or grilled on the BBQ.
- Raw garlic is another easy prebiotic ingredient to use that offers loads of benefits. Not only can raw garlic benefits help boost gut health, but studies have shown it to have powerful antifungal, antioxidant, anti-inflammatory, antiviral and anti-cancer properties. Try using some in a tomato salad, dips, spreads or homemade hummus.
- Nutrient-dense bananas that aren’t yet fully ripe contain the highest concentration of resistant starch and prebiotics. Look for bananas that are still greenish instead of bright yellow and spotted. While they won’t be as soft or sweet-tasting, they still work well in smoothies or even warmed up as a dessert.
- Dandelion greens are another food that can be found in most grocery stores and nearly all health food stores. These leafy greens are a great source of prebiotics in addition to antioxidants, vitamins and minerals. Eat them raw by chopping them up finely and adding some to a salad or side dish.
- If eating asparagus raw doesn’t initially appeal to you, try fermenting it. You can easily make homemade fermented asparagus (and many other veggies too) with just some salt and a mason jar. The same goes for jicama — either slice it thinly and throw in a salad for some crunch, or try bringing out the natural flavors and probiotics by making cultured jicama sticks.
- Jerusalem artichokes, often called sunchokes, are more similar to a root vegetable than the large green artichokes you’re probably familiar with. Try shredding them and sprinkling some on top of a salad, into a smoothie or into a dip. They have a mild flavor and blend easily with other tastes.
- Chicory root is useful for baking since it binds ingredients together. It’s also a high-antioxidant food and great digestive cleanser. Some people use chicory when making homemade cultured veggies, like kimchi or sauerkraut. Chicory root is also used as a coffee substitute for those looking to cut their caffeine intake since its taste mimics that of coffee without any of the caffeine or acidity.
- Acacia gum is used in a variety of products, including some supplements, powders and even ice cream. In herbal medicine, the gum is used to bind pills and lozenges and to stabilize emulsions. It’s possible to find powder acaia to add to smoothies in certain health food stores or online.
Supplements and Dosage Recommendations
Some prebiotics are added to some foods artificially and can often be found as dietary supplements, such as Prebiotin, which is a prebiotin fiber that can be sprinkled on foods and dissolved in drinks.
While many food manufacturers now produce foods that are “high in fiber,” many use isolated fiber sources that are difficult to digest, and some might even have mild laxative effects.
What is the best prebiotic to take? The best prebiotics come from whole food sources and foods containing prebiotics, like raw chicory root or onions. Not only do these foods supply a concentrated amount of prebiotics, but they are also rich in other important vitamins, minerals and antioxidants that can help optimize your health.
Focus on eating plenty of fiber-rich foods, aiming to get 25 to 30 grams of fiber each day from a variety of whole foods.
That said, if you’re unable to meet your needs through food alone, you may want to consider prebiotics and probiotics supplements. Look for a supplement that contains real prebiotics instead of compounds with prebiotic-like effects, and be sure to buy from a reputable retailer with high-quality standards as well.
Additionally, it’s important to stick to the recommended dosage to avoid adverse symptoms and gastrointestinal problems. You may also want to start with a low dose and gradually increase your intake to assess your tolerance and minimize the risk of side effects.
Prebiotics and probiotics can be taken at the same time. Ideally, take them daily around at the same time each day in order to establish a consistent routine.
How long do prebiotics take to work? This really depends on the individual. Like other dietary changes, you may notice some benefits within several days or need to be consistent for several weeks before experiencing changes like improved digestion.
- What are prebiotics? They’re non-digestible fiber compounds that pass through the upper part of the gastrointestinal tract and end up in the colon, where they’re fermented by the gut microflora.
- Why should you take prebiotics? Some benefits of prebiotics include:
- Better gut health and improved digestion
- Enhanced immune function
- Lower inflammation
- Reduced risk of heart disease
- Aid in weight loss
- Protect bone health
- Regulate hormone levels and mood
- Are prebiotics better than probiotics? Increasing your intake of prebiotics and probiotics together could help improve gut health and immune function, reduce inflammation, enhance heart health, support weight loss, boost bone health, and regulate hormone levels and mood.
- Foods with prebiotics include many fruits, vegetables and whole grains, such as under-ripe bananas, raw garlic, onions and acacia gum. They can be found in supplement form as well.
- While they’re generally very safe, potential prebiotics side effects may include abdominal pain, gas, bloating and diarrhea.