By Susha Cheriyedath, MSc
Years of research has established the key role played by the colon and the good bacteria in promoting overall human health. The useful bacteria in the colon have many important functions including enhancing mineral absorption, strengthening the intestinal wall and regulating the production of hormones.
While probiotics are well known as the beneficial microorganisms that live in the gut and help in the digestion of food and in fighting harmful bacteria, there has been little focus on prebiotics and their health benefits. Both prebiotics and probiotics have their own key functions in maintaining the health of the human gut.
Probiotic (or prebiotic) rich foods including pulses, nuts, fruit and milk products, good for immunity and the gut. Image Copyright: Pixelbliss / Shutterstock
What are Prebiotics?
Prebiotics are natural, plant fibers that are non-digestible by the body. They are present in the diet and function as a fertilizer for probiotics. Good microbes in the gut feed on these complex carbohydrates and grow in numbers, thus improving the ratio of good bacteria to harmful bacteria in the gut, which in turn promotes overall wellbeing of the body.
Where are Prebiotics and Probiotics Found?
Probiotics are found in fermented dairy foods like yogurt, aged cheese and kefir. Aged cheese contains live cultures of organisms such as lactobacilli and bifidobacteria. Non-dairy foods such as soy beverages, miso and kimchi also contain beneficial microbial cultures. Probiotics are also available in the form of pills and are used to treat intestinal infections.
Prebiotics are naturally found complex carbohydrates in our diet. Examples are inulin and galactooligosaccharides which belong to the category fructooligosaccharides. These carbohydrates are commonly found in foods such as onions, bananas, garlic, asparagus, whole-wheat foods, leeks and soybeans.
Uses of Prebiotics and Probiotics
Probiotics are widely used in the treatment of diarrhea and to treat the gastrointestinal side effects of antibiotic treatment, as antibiotics tend to destroy the good microbes in the gut. Probiotics help prevent as well as treat infections of the urinary tract and vaginal yeast infections. They are known to play a role in preventing or treating colds and flu. They are also used in treating irritable bowel syndrome and to speed up the treatment of intestinal infections.
Prebiotics promote the growth of good bacteria in the gut, thus enhancing overall gastrointestinal health. They are also said to promote, improve and enhance calcium absorption. Studies have shown that prebiotics and a healthy gut can help improve mental health and regular consumption of prebiotics can fight stress, anxiety and depression. These research studies tested the saliva of people who consume prebiotics regularly and found decreased levels of cortisol, a hormone that is directly linked to mental disorders.
Although very beneficial to the body, probiotics have a few disadvantages. They are delicate organisms that are easily destroyed by heat and acidity in the stomach. People who do not or cannot consume dairy products may not ingest enough probiotics, though supplementation is an option. Also, different probiotic microorganisms work differently in different people, hence the effectiveness of various probiotics may not be the same for all.
On the contrary, prebiotics are not destroyed by acidity or heat and they are present in a wider range of foods including common vegetables and fruits, making it easy to exploit their benefits to the maximum. However, they are also available in supplement form as it can be difficult to ingest enough prebiotic–rich food in your diet. This is because most of these fruits and vegetables contain only minute amounts of prebiotics.
Combining probiotics and prebiotics gives rise to products known as synbiotics that have both good microbes as well as food for them. So a meal combining banana (prebiotic) and yoghurt (probiotic) is an ideal synbiotic in which the prebiotic and probiotic work together in a synergistic manner to improve overall health.
Reviewed by Yolanda Smith, BPharm
Last Updated: Jul 8, 2016