Every part of our digestive system has a role to play in the processing of food. The role that the large intestine plays is particularly interesting as it is home to a vast variety of microbes especially bacteria which have a positive influence on our health. In fact, our overall health depends on the balance between the useful bacteria and the less useful ones. Prebiotics and probiotics help us to maintain this balance.
When it comes to prebiotics which is often interchanged with probiotics, one normally associates them with the large intestine also called the colon. Prebiotics and probiotics are two different entities and shouldn’t be confused as one. One can consider prebiotics as the food for the bacteria in the colon whereas probiotics are live beneficial bacteria.
What are Prebiotics?
One can define prebiotics as the food fibers that pass the upper gastrointestinal tract undigested and serves as food for the bacteria in the large intestine. They selectively promote the growth of healthy gut bacteria and inhibit the growth of the disease-causing bacteria.
Not all dietary fibers can be classified as prebiotics, they should meet certain criteria to be classified as them. Prebiotics should be;
- Non-digestible fiber
- Resistant to enzymes and stomach acid in the digestive tract
- Readily ferment-able by selective gut bacteria
- Target and stimulate the growth of selective bacteria in the large system.
Prebiotic Food Sources
Here’s the list of prebiotic foods:
It is almost 65% of fiber by weight. Hence, it is one of the best food sources of prebiotics. It is rich in inulin, a type of soluble fiber that helps to nourish the gut bacteria and also aids in digestion & relieves constipation. Apart from being a great source of prebiotics, chicory root is also high in antioxidants which protect the liver from damage due to oxidation.
Also known as earth apple, Jerusalem artichokes helps to increase the friendly colon bacteria and are rich in inulin. They provide 2 grams of dietary fiber per 100 grams.
They are normally used in salads and are rich in inulin. Dandelion greens contain about 4 grams of fiber per 100 grams. The inulin fiber present in them helps to increase gut-friendly bacteria, reduce constipation and boosts the immune system.
It is a medicinal herb that has immense benefits. Like most other food sources of prebiotics, garlic also is rich in inulin. It promotes the growth of beneficial bacteria especially Bifidobacteria and inhibits the growth of harmful bacteria.
It belongs to the same family as onions & garlic and contains around 16% of inulin fiber. Along with promoting healthy bacteria, leeks also help in the breakdown of fat.
This versatile vegetable contains about 10% of inulin fiber and 6% of FOS. It helps to enhance the gut bacteria and has anticancer & antioxidant properties.
Along with promoting friendly bacteria, it also prevents certain types of cancers. It contains about 2 to 3 grams per 100 grams.
They contain small amounts of inulin and are rich sources of vitamins, fiber, and minerals. Raw bananas contain resistant starch which is also known to show some prebiotic effects.
It is an excellent source of prebiotics and contains a special type of fiber composed of arabinoxylan oligosaccharides (AXOS). This fiber promotes the growth of Bifidobacteria which is a friendly bacteria found in the gut.
Even though we can find prebiotics in our everyday foods as mentioned above, we need to consume large portions of these foods to enjoy their full benefits. Hence it is advisable to take the prebiotics as supplements. Regular uptake of prebiotic supplements ensures the enhanced growth of friendly bacteria in the large intestine.
Benefits of Prebiotics
Reduces the Risk of Cardiovascular Diseases
Glycation a natural process in our bloodstream where the sugar attaches to the proteins or the lip molecules leading to harmful new molecules is the root cause of many health conditions. It increases the free radicals, can trigger inflammation and lowers insulin resistance. All of this can contribute to cardiovascular diseases. Intake of prebiotics reduces the risk of glycation.
The cholesterol reducing properties of the prebiotics help to reduce the risk of heart diseases as well as some of the autoimmune disorders especially arthritis. They also help to control blood pressure by balancing the body’s electrolyte and mineral levels.
Enhanced Gut Health and Improved Digestion
One can consider prebiotics as the indigestible fiber used by the gut bacteria as a food source for their survival. As the gut bacteria metabolize the non-digestible fibers through the process of fermentation, they give out short-chain fatty acids (SCFAs) such as acetate, propionate, and butyrate. These compounds are known to boost a wide range of benefits.
SCFAs help to improve the health of intestinal lining. In addition, SCFAs can regulate the body electrolyte levels. This helps to promote digestion and provide relief from diarrhea and constipation. Prebiotics in combination with probiotics can treat many of the digestive problems such as irritable bowel syndrome, leaky gut, Crohn’s disease, ulcerative colitis, and inflammatory bowel disease.
Aids in Weight Loss
Higher intake of any kind of fiber is associated with lower body weight. A recent study on animals and humans suggest that particular prebiotic foods help to maintain energy homeostasis and aids in weight loss.
The prebiotic foods give a feeling of fullness, causes weight loss and protects from obesity. They are known to affect the hormone levels that regulate the appetite.
Prebiotics bring about significant changes in the composition of the gut microflora which boost the immunity. This prebiotic effect brings about improvement in biomarkers and activities of the immune system that also includes decreased levels of bacterial metabolites in the gut and certain enzymes that can cause cancer.
Prebiotics improves nutrient absorption and lowers the pH in the gut. This helps to block the growth of any harmful bacteria or potential pathogens. They act as fuel for the gut bacteria and this helps treat a range of health conditions such as intestinal disorders, eczema, allergies, and even viral infections.
Regulates Hormones and Mood
Anxiety, depression and other mood-related disorders are closely related to gut health. A combination of factors influence your mood and hormonal balance. The state of the gut bacteria is definitely one of those factors that regulate the hormones and mood.
Your gut helps your body to absorb and metabolize the nutrients from the food you eat. These, in turn, support the neurotransmitter functions which help to create hormones that control your mood and relieve stress.
Inflammation is the root cause of many chronic diseases. By increasing the intake of prebiotics and fiber, your cholesterol levels remain healthier and lowers the risk of heart diseases. It contributes to improvements in the metabolic processes in relation to type 2 diabetes and obesity.
Prebiotics help to promote a healthier gut environment. This, in turn, is more beneficial and prevents the autoimmune reactions, helps the body to effectively metabolize the nutrients and modifies the immune functions that determine how and where the body stores fat.
Protects the Bones
By enhancing the absorption of minerals such as magnesium and even iron & calcium, prebiotics help to promote bone health. These minerals help to maintain strong bones and also prevent osteoporosis & fractures.
As the fermentation of the prebiotics takes place in the large intestine, too much intake of prebiotics can give rise to side effects such as abdominal pain, bloating and diarrhea. Since prebiotics are fiber- rich foods, they absorb the water in the colon. This may slow down the digestion process and may also cause serious side effects such as dehydration.
It is advisable to take small amounts of prebiotics initially and then increase the intake gradually to overcome the side-effects. Also, increase your water intake while you are eating plenty of prebiotics.
Difference between Prebiotics and Probiotics
Prebiotics are non-living indigestible fibers that act as the food source for your beneficial gut bacteria whereas probiotics are live and active bacteria that enter the gut through food and supplements. The main role of prebiotics is to feed and increase the population of the probiotics and at the same time inhibit the growth of the pathogens.
The probiotics aid in the process of digestion & food absorption and regulates the immune system. Prebiotics are resistant to heat, enzymes, stomach acids and oxygen. Hence you can take them with food and they reach the lower gut intact. Probiotics must be kept alive to reach the colon in the required numbers