The gut is the body’s primary organ involved in immune function; roughly 60% of the body’s immune cells reside in the intestinal lumen. Our gut microbiome comprises a diverse array of microorganisms, both beneficial and detrimental. Most people are well aware of probiotics, the living bacteria believed to promote gut health. Probiotics are naturally present in certain foods like yogurt, sauerkraut, and kimchi and are also often taken in supplement form to aid support the digestive system. But there is another component required by our gut microbiome to work efficiently: Prebiotics. What are they, and how do they help maintain the gut flora?
Prebiotics are naturally present, non-digestible carbohydrates (fibers) that encourage the production and activity of the beneficial bacteria in our gut by acting as a food source for them.
Even though all prebiotics is fiber, not every fiber fits the requirements to be classified as a prebiotic. A kind of fiber must satisfy all three of the following characteristics to be termed a prebiotic:
- They should be resistant to stomach acid and digestive enzymes and should not be absorbed via the GI tract and reach large intestines.
- Must be fermentable by intestinal microbiota.
- It must be beneficial to certain kinds of friendly bacteria in the colon to improve health.
Probiotics are important — but obviously won’t operate without prebiotics. They aid in eradicating pathogenic bacteria while providing food for beneficial probiotic bacteria.
Prebiotics serves as a food supply for the bacteria in your stomach, and they must avoid digestion to reach your colon. To live, the bacteria metabolize and ferment the prebiotics. This metabolic and fermentation process is important to gut health since it generates several byproducts that are advantageous to your health.
Types of Prebiotics
There are many different types of prebiotics which are mentioned here,
1. Fructans. This category includes inulin, fructo-oligosaccharides, or oligofructose. Fructo-oligosaccharides (FOS) are prebiotics that nourishes the microorganisms in the intestines. They are short-chained sugar molecules that the body isn’t able to digest. They pass through the intestines through the stomach, where they are consumed by good bacteria and yeast. They cleanse the system, aid digestion, and increase immunity throughout this process.
Inulin is one of the most frequent types of FOS; it is a natural combination of fructose polymers. Oligofructose is a subset of inulin that comprises polymers with some polymerization. Both of these are natural food elements that are often found in various dietary items. This prebiotic may help you feel full for longer, reducing overeating and enhancing digestive function. It may also aid in lowering LDL cholesterol (bad cholesterol), stabilizing blood sugar levels, and increasing and sustaining the number of beneficial bacteria in the stomach. Additionally, it may lessen the risk of colon cancer.
2. Galacto-oligosaccharides (GOS). Also known as oligogalactose, oligogalactosyllactose, transgalactooligosaccharides, and oligolactose. A significant amount of GOS can be produced by Bifidobacteria and Lactobacilli, and to a lesser level by Enterobacteria and Bacteroidetes and Firmicutes. Numerous research with adults and newborns has shown that drinks and meals containing GOS greatly improve bifidobacteria health and counts. Additionally, numerous research projects, including adults and the elderly, have shown that GOS has a laxative effect. American Journal of Clinical Nutrition reported that GOS supplementation decreased the number of days with flu or cold in academically pressured college students.
3. Starch and Glucose-Derived Oligosaccharides. Resistant starch, which is a form of starch that is resistant to digestion in the upper intestine, may induce the creation of butyrate, a short-chain fatty acid, in the stomach (SCFA). In contrast to other types of starch, resistant starch (RS) is not decomposed by digestive enzymes (like amylase or pullulanase) but instead just goes through our digestive system intact. Polydextrose, an oligosaccharide produced from glucose, has been shown to boost Bifidobacteria growth.
4. Other Derived Oligosaccharides. It is believed that some of the oligosaccharides are derived from the polymer known as pectin. It is named Pectin oligosaccharide (POS). Pectin is a gel-forming fiber that readily absorbs water and has been shown to regulate bowel movements. In two trials, individuals who consumed 24 grams of pectin daily had less diarrhea and constipation symptoms.
Xylooligosaccharides (XOS or XOS Prebiotics) is derived from plant fiber and are natural prebiotics. It strategically nourishes beneficial microorganisms and promotes intestinal health.
Inulin and oligofructose are two forms of prebiotics that remain in the digestive tract and help develop beneficial bacteria.
How Are Prebiotics Beneficial to One’s Health?
When consumed in sufficient quantities, prebiotic foods help to maintain digestive system health by promoting the development of beneficial microbes.
Short-chain fatty acids (SCFAs) are produced during the fermentation of prebiotics, and they include acetate, propionate, and butyrate. They perform vital functions in the health of the gut and metabolism.
Prebiotics Improve Gut Microbiome.
Prebiotics may aid individuals who suffer from gut-related health disorders such as constipation since they promote the development of good bacteria and enhance some elements of gut health.
- A 2020 review stated that supplementation with inulin, a form of prebiotic, may assist persons who have irritable bowel syndrome (IBS) with constipation.
- According to a review, it may increase stool frequency, consistency, and intestinal transit time.
- A 2021 review found that there is minimal evidence that prebiotics — or combined with probiotics (Synbiotics) — are beneficial for treating irritable bowel syndrome (IBS).
- It has been shown that as low as 4g/day of FOS has a beneficial impact on colonic microbiota.
- Prevention for Colonic cancer. Probiotic fermentation products, such as butyrate, have been shown to protect against colorectal cancer risk. (1) (2)
Prebiotics Improve the Immune System.
Consuming prebiotics may help boost immunity by expanding the population of beneficial microbes. The benefits may be direct or indirect, resulting from an increase in the population of beneficial microorganisms or probiotics, particularly lactic acid bacteria and bifidobacteria.
- Prebiotics has been demonstrated in human studies to reduce the population of dangerous bacteria produced by Lactobacilli and Bifidobacteria. (1) (2)
- Another research showed substantial reductions in one or more indicators of systemic inflammation, according to a 2017 study. SCFAs may help decrease inflammation by protecting the intestinal lining and blocking pro-inflammatory molecule migration through the gut wall.
- Early research has linked increased consumption of prebiotics and probiotics to increased resistance to flu – particularly when combined with the flu shot. This seems to increase resilience and suggests that intestinal bacteria may play a role in general health and disease resistance.
Prebiotics are Good for Metabolism.
Consuming a prebiotic-rich diet and supplementing with prebiotics may enhance various elements of metabolic health, such as blood sugar, cholesterol, and serum triglycerides.
- A 2019 meta-analysis of 33 research indicated that prebiotics labeled Inulin-type fructans (ITF) substantially lowered fasting blood sugar, glycosylated hemoglobin (HbA1c), and fasting insulin levels. According to the same study, pre-diabetics and diabetics should take 10 grams of ITF every day for 6 weeks or longer to experience the possible advantages.
- Another similar study done in 2021 indicated that Inulin-type fructans ITF supplementation dramatically lowered blood sugar, total cholesterol, and triglycerides in patients with prediabetes and diabetes.
Prebiotics Help Lose Fat.
- Some research has shown that supplementing prebiotics such as galacto-oligosaccharides and oligofructose-enriched inulin may help to lower hunger and desire for food types, such as sugary meals. (2)
- A 2021 evaluation of 27 research showed that Synbiotics, or the combination of pre & probiotics, may help those who are overweight or obese lose weight and fat.
- According to research published in 2017 in the American Journal of Clinical Nutrition, children who drank prebiotics felt fuller after a meal, suggesting that they may be a valuable tool for appetite management.
Prebiotics Help Absorb Calcium.
While prebiotics has been established to benefit a variety of chronic inflammatory disorders, there is emerging evidence that they yield more benefits than previously researched:
- It has been shown that these novel dietary fibers improve calcium absorption in both preclinical and human settings. Primarily fructans have been demonstrated to improve calcium absorption in studies.
- A 12-month study of 100 teenagers who consumed 8 g of short- and long-chain inulin fructans daily showed a substantial increase in calcium absorption, resulting in increased bone mineral density without impairing the absorption of other minerals such as magnesium, iron, or zinc.
- Additionally, inulin has also been shown to significantly raise the uptake of other minerals, such as magnesium and iron, in the body.
But if we have to find some differences between prebiotics and probiotics, here is the table,
|Type||Non-living, ingestible but fermentable fibers||Live microorganisms|
|Functions||Works as food for probiotics, increase their activity and number||Improves the health and wellbeing of the digestive tract|
|Health Benefits||Provide a supportive function to probiotics||Reduce the number of harmful bacteria in the gut, improve its function, and prevent diarrhea and IBS. Helps to cure cold m u, weight loss, and mental health functions.|
|Sources||Asparagus, Oatmeal, Jerusalem artichokes, bananas, and legumes||Yogurt, Miso, Kimchi, Kombucha etc.|
Prebiotic effects are related to probiotic benefits. Prebiotics may promote gut health by improving digestive health, reducing antibiotic-related health concerns, and providing other advantages.
List of Prebiotic Food
The bulk of research on gut health has been on probiotics, with prebiotics being a relatively recent emphasis. By having various items in their diet, people may guarantee that they ingest a spectrum of prebiotics that may feed diverse kinds of bacteria.
There are no defined norms or rules defining what being “rich in prebiotics” means since the US Food and Drug Administration (FDA) has not yet created clear regulations categorizing or labeling prebiotic foods. Prebiotics are found in many high-fiber foods, including various fruits, vegetables, and whole grains. The following are considered good in this regard.
1. Jerusalem Artichoke. Jerusalem artichoke, also known as sunroot, sunchoke, or earth apple, is a sunflower family member with several health advantages. Consuming this fibrous vegetable may help boost the number of beneficial bacteria in the stomach. Jerusalem artichokes are high in prebiotics such as inulin and oligofructose and minerals like potassium. The vegetable has roughly 2 grams of inulin-rich dietary fiber per 100 grams.
They are strong in thiamin, or vitamin B1. So, they are considered good for muscular function as a deficiency in thiamin may result in lethargy and impaired muscular function. This superfood may help boost your immune system as per research, decrease cholesterol and possibly prevent some metabolic problems.
2. Asparagus. The majority of prebiotic-rich vegetables include inulin, which has been studied to promote the growth of beneficial gut bacteria such as Bifidobacteria. It has been studied that it may also improve digestion, influence the immune system, and aid in restoring the gut microbiota’s microbial integrity after antibiotic therapy. Asparagus has been associated with reducing the risk of developing some malignancies. It includes around 2 to 3 grams of inulin per 100 grams and has a better effect if it is raw.
3. Chicory Root. Coming from a family of dandelions, it is well-known for its coffee-like taste and has been used in cooking and healing for centuries. By dry weight, fresh chicory root contains 68 % inulin. Chicory root also contains helpful molecules and minerals such as potassium, calcium, magnesium, selenium, and zinc. It functions as a prebiotic, feeding the healthy microorganisms in the stomach. These beneficial bacteria have been studied to aid in reducing inflammation, the battle against bad bacteria, and the enhancement of mineral absorption.
It has also been studied to aid in constipation relief; 4-week research of constipated persons revealed that 12 grams of chicory inulin softened stool and increased bowel movement frequency per day. It may also help prevent diabetes by increasing adiponectin, a protein that regulates blood sugar.
4. Garlic. Garlic functions as a prebiotic by stimulating the development of healthy bacteria in the stomach known as Bifidobacteria. Additionally, it aids in the prevention of disease-causing microorganisms from developing. Additionally, it is high in fructooligosaccharides and inulin prebiotics, which nourish the beneficial bacteria. It has almost 15-20g of inulin in 100 g of garlic. Furthermore, garlic has been demonstrated to suppress the development of harmful Clostridium bacteria in the stomach owing to its antibacterial capabilities. Apart from inulin, garlic has a trace of vitamin C and B6 and manganese and selenium, according to the USDA.
5. Onions and Leeks. Onions are a wonderful vegetable with many health advantages. Onions, like garlic, contain inulin and FOS. This FOS promotes the immune function by boosting nitric oxide generation in cells, strengthening gut flora and fat breakdown. Leeks are also from the same Allium family, and they can contain up to16% inulin fiber. They have been shown to aid in fat breakdown and increase the growth of beneficial gut flora.
6. Bananas. A banana is more than just a vibrant, tasty fruit; it is a rich source of nutrients, including vitamins, minerals, fiber, and trace amounts of fiber inulin. This inulin is more profoundly present in unripe, the green ones to reap the benefits fully. Unripe (green) bananas also have a high concentration of resistant starch, which acts as a prebiotic as per research. Additionally, resistant starches may assist in improving insulin sensitivity and blood sugar control which are the risk factors for diabetes and obesity. Bananas include 2.6 grams of fiber per 100 grams.
7. Apples. “An apple a day keeps the doctor away” is also true for digestive health since apples are an excellent source of prebiotic pectin. Indeed, almost half of the fiber in apples is pectin, a prebiotic fiber that nourishes the intestinal bacteria that produce butyrate. Butyrate, or butyric acid, is a short-chain fatty acid that is created by beneficial bacteria during glucose fermentation. According to research, it decreases inflammation, aids in the maintenance of the intestinal barrier, and nourishes the cells that line the colon. It may also help suppress the development of dangerous bacteria in the digestive system, such as Clostridium and Bacteroides.
2016 research revealed that apple pectin might improve gut microbiota, reduce inflammation, and slow weight gain in obese mice. Apples have also been shown to promote heart health and lessen the risk of asthma and other respiratory illnesses.
8. Barley. It contains 2–20 grams of beta-glucan per 100 grams. Beta-glucan is a prebiotic fiber that aids in the development of beneficial bacteria in the intestines and has been proven by several researchers. (1) (2). Barley’s beta-glucan also lowers total and LDL (bad) cholesterol, lowering the risk of heart disease. It may also help reduce blood sugar. Another new research in 2021 has highlighted the use of barley as an improver in immunity,
9. Konjac Root. Konjac is a root vegetable native to Asia. It is well-known for its starchy corm, a subterranean tuber-like portion of the stem. The corm produces glucomannan, a form of soluble dietary fiber. Its flour can contain up to 70-90% glucomannan. Konjac glucomannan stimulates the formation of beneficial bacteria in the colon and may aid in constipation relief. 2018 research found that glucomannan supplementation may help with pregnancy-related constipation as it allegedly enhanced stool frequency and consistency.
10. Flaxseeds. Flaxseeds are abundant in prebiotic inulin, making them a digestive powerhouse. The fiber content of flaxseeds is 20–40% soluble fiber from mucilage and 60–80% insoluble fiber from cellulose and lignin. Flaxseed fiber supports healthy gut flora and regular bowel movements and lowers dietary fat digestion and absorption.
11. Wheat Bran. Wheat bran is the grain’s outermost coating. It is a good source of prebiotics. Additionally, it has a unique fiber composed of arabinoxylan oligosaccharides (AXOS) which is almost 69% of the total fiber content of the bran. AXOS fiber derived from wheat bran has been demonstrated to increase the number of beneficial Bifidobacteria in the stomach. One research indicated that a higher wheat bran diet for 3 weeks boosted Bifidobacteria levels in healthy persons. Wheat bran also reduces digestive issues, including gas, cramps, and discomfort. (1) (2)
|1. Jerusalem Artichoke.||Inulin (2grams in 100 gm)|
|2. Asparagus.||Inulin (2-3 gram/ 100 gm)|
|3. Chicory root.||68% Inulin in medium-sized.|
|4. Garlic||9–16 g Inulin in 100 grams.|
|5. Onions and Leeks.||16% Inulin.|
|6. Bananas||2.6 grams/100grams total, 0.5 of Inulin & fructose.|
|7. Apples.||Pectin 15-20%|
|8. Barley.||beta-glucan 2-20 grams/100gm.|
|9. Konjac Root.||Glucomannan 70-90%|
|10. Flaxseeds.||20-30% mucilage, 60-80% insoluble fiber.|
|11. Bran.||AXOS (arabinoxylan oligosaccharides) 68% of total content, Inulin -5-1g/100g|
Many foods naturally contain prebiotics; therefore, there is no need for consumers to augment their diets with prebiotic supplements. However, to learn more about probiotics and how they benefit our body, refer to our article here.
Prebiotic Supplements Do They Work?
Although including prebiotics in your diet is optimal, you may boost your consumption with prebiotic supplements. Prebiotics are an efficient technique to stimulate the development of anaerobic bacteria, which are critical for health. Taking a prebiotic supplement may be especially effective when eradicating anaerobic bacteria from the stomach. Anaerobic bacteria cannot survive or develop in the presence of oxygen, so they cannot be synthesized into nutritional supplements.
Benefits of Supplements.
- Helps in IBS. According to a study published in the British Journal of Gastroenterology, Prebiotic supplements may reduce anxiety and improve IBS symptoms.
- Good for Infant’s Gut. Researchers in 2021 also found that prebiotic-containing infant formula may aid in the early colonization of beneficial bacteria in the baby’s gut.
- Prevents Colorectal Cancer. Butyrate and other fermentation products of probiotics protect against colorectal cancer risk.
- Decrease the Risk of Skin Allergies. Prebiotics reduce both the incidence of and severity of atopic dermatitis.
Drawbacks of Supplementation
Prebiotics are good for you. Nonetheless, do you need to complement your diet with any kind of supplement? You may want to learn about the downsides of prebiotic supplements before purchasing.
- Unpleasant Side effects. Prebiotics might cause unpleasant gastrointestinal side effects. As a fiber, they may produce gas and bloating.
- Lack of Regulation. Unlike medications, the FDA does not regulate dietary supplements and does not require producers to demonstrate that their products function before they are placed on the market.
- Not a Substitute for Real Food. Supplements are no replacement for the nutrients obtained from real food and should not be used in place of a balanced, diverse diet. (1) All the “synergistic benefits” of a balanced diet are lost when a single nutrient is isolated and added to a supplement. In other words, eat asparagus or bananas, which are abundant in prebiotics and other necessary nutrients.
Remember that they do not include all of these additional perks. Despite what the packaging may claim, a broad and balanced diet has repeatedly been proven to help promote general health, maintain healthy body weight, and prevent illness.
Estimated time for Prebiotics to work? Unlike caffeine or other supplements, prebiotics takes time to function. The digestive system is a sluggish region. Prebiotic vitamins need consistency and patience since cells and bacteria transform slowly. When most individuals begin taking probiotics, it takes between 2-3 weeks to see substantial effects. This is because probiotics need time to complete their three primary objectives: increasing the number of beneficial bacteria, decreasing the number of harmful bacteria, and reducing inflammation. However, it may be the potential to experience initial results within three to four days of intake.
Dietary Recommendations for Prebiotics: Unlike fiber, prebiotics does not have an official dietary requirement. However, ISAPP recommends consuming 3 grams of prebiotics daily and, more generally, consuming 28 grams of fiber daily (based on a diet of 2000 kcal per day)
Best time to Consume Prebiotic Supplement? To get the most concentration of probiotics from your supplement, it is essential to take them at the optimal time. Research indicates that the optimal time to take probiotics is shortly before or as you begin eating. Prebiotics should be taken with water, not on an empty stomach. These supplements can be taken in the morning or before bedtime. To develop a regimen, take prebiotic pills at the same time every day. For treatment of IBS, it should be taken in a lesser dosage in the beginning at the same time every day. Most individuals may benefit from combining prebiotics and probiotics.
Our current westernized diet is mostly made up of processed foods that are low in nutritional content and deficient in dietary fiber. The majority of Americans do not consume the recommended daily intake of 3-5 grams of prebiotic fiber. Utilizing a prebiotic supplement may assist you in obtaining the appropriate quantity in the most convenient and effective manner possible. When selecting supplements, it is important to choose those that adhere to the highest scientific standards since this ensures the product’s quality and efficacy. And this can always be best suggested by your general physician or gastroenterologist.