While probiotics are fairly well known by the public and their benefits have been researched and largely understood, prebiotics are not as well-known and receive far less attention. Probiotics are essentially living bacteria typically found in certain dairy products such as yogurt and kefir.
This ‘good’ bacteria is known to help the digestive system and might also boost your immunity. Prebiotics on the other hand are soluble plant fibers which nourish the good bacteria that are already present in the gut. The essential difference is that probiotics introduce bacteria while prebiotics help nourish and fertilize it.
Advocates of prebiotic supplements claim that they are necessary because we do not derive sufficient amounts from our regular daily diets while others suggest that the difference between prebiotics and regular fiber is marginal. Simply making sure that you get enough fiber in your system will be beneficial to your health in many ways but is there a need to increase your intake of prebiotics?
Natural Source of Prebiotics
While prebiotics are available in supplement form, prebiotics can be derived from certain natural fibrous foods. Not all soluble fiber is a prebiotic but all prebiotics are found in soluble fiber and the best known and most well researched prebiotic fibers are inulin and oligofructose (FOS). Inulin is found in prebiotic supplements and FOS is found in certain fibrous foods such as the following:
In order to retain their prebiotic benefits, the food listed above should be eaten raw and even then the quantity is fairly small which makes prebiotic supplements an attractive option. As well as encouraging the growth of good bacteria which aids digestion, recent research has discovered the potential of prebiotics in the area of mental health.
Advocates and manufacturers of prebiotic supplements make a number of claims regarding their benefits though the research is not always that well-established up to now. If you are interested in the benefits of prebiotics on your physical and mental wellbeing then read on.
Prebiotics increase the absorption of calcium and magnesium according research on post-menopausal women. (1) A deficiency of estrogen in menopause is associated with a decreased absorption of calcium while magnesium deficiency is also linked to bone loss. The study demonstrated that oligofructose could improve the absorption of minerals and lead to healthier and stronger bones.
2. Immune System Enhancement
There is evidence that prebiotic supplements can boost the immune system in times of anxiety or increased stress. One study published in 2011 was carried out on 419 healthy college students to examine the benefits of prebiotic supplementation. (2)
The students randomly separated into three groups received either 5 grams, 2.5 grams or no prebiotic supplement for an eight week period leading up to, during and following their final examinations. The students who received prebiotic supplements suffered fewer gastrointestinal problems such as constipation, diarrhea, indigestion or abdominal pain.
Those who received the highest 5 gram supplement experienced 40% fewer days with cold and flu. These findings suggest that prebiotic supplements might have a beneficial protective effect on the system especially during times of stress.
3. Heart Health and Cholesterol Reduction
Heart disease is the leading cause of death worldwide and it is predicted to remain the world’s biggest killer for decades to come. A reduction in cardiovascular disease is a priority and there is some evidence to suggest that prebiotics can work to reduce cholesterol levels and improve the health of your heart but the results of research have been mixed and the evidence is inconclusive. (4)
Research has however indicated that prebiotics might reduce cholesterol levels. One study on 23 people with high lipids demonstrated that a combination of soy protein and a prebiotic (FOS) might reduce LDL cholesterol. (5)
4. Mental Health
It seems an odd concept that the bacteria inhabiting your gut could have any sort of effect on your brain but recent research carried out by researchers at Oxford University has demonstrated that it does. (6) According to the study, consuming prebiotics affected emotional responses as well as the levels of stress hormones produced by otherwise healthy volunteers.
The researchers at Oxford sought to discover whether prebiotics had a similar affect in lowering anxiety as probiotics.
Volunteers were separated into three groups taking either a placebo or one of two types of prebiotic for a three week period. At the end of the three weeks volunteers were required to complete a set of tasks to test emotional processing.
The results were conclusive. Volunteers that took a certain prebiotic (B-GOS) paid more attention to positive words and less to negative words than those in the other groups. What is more, those taking the same prebiotic had a reduced level of cortisol- a stress hormone in examined saliva at the conclusion of the study.
It is worth noting that volunteers who took another type of prebiotic – FOS – demonstrated neither of these beneficial effects. Previous studies had already demonstrated that B-GOS stimulated intestinal microbe growth more than FOS and this study highlighted the difference. When considering a prebiotic supplement, it is important to realize that all prebiotics are not created equal.
5. Leaky Gut Prevention
Maintaining a healthy balance of gut flora is essential; these good bacteria help to line the colon and protect the body from pathogens. When this lining is weakened, the intestines can become permeable and can cause harmful bacteria and pathogens to enter the blood stream. This condition is often referred to as ‘leaky gut’ syndrome and can lead to a number of complaints.
Prebiotic supplements in baby formulas might help prevent the development of eczema and dermatitis according to research. It is already established that mother’s breast milk contains naturally produced prebiotics which promote the healthy development of the infant’s immune system and protect against allergies.
The study carried out in Germany and published in 2006 sought to test the ability of prebiotics to reduce incidence of skin allergies in high risk infants whose mothers could not breast feed their children. After 16 months, significantly fewer of the children fed the prebiotic formula had developed symptoms of eczema compared with the control group. (3)
The study also showed that the group taking prebiotic formula had significantly greater levels of beneficial stomach microbes compared to the group fed with normal infant formulas. The researchers concluded that prebiotic supplements could improve the immune system by changing the gut bacteria. This leads to a reduction in the chance of atopic dermatitis developing in children who are at risk of skin allergies.
Several studies have shown that certain prebiotics, specifically inulin type fructans can alter the composition of gut microbes and moderately aid weight loss in obese people. (7)
Prebiotic supplements are available in several different forms and are relatively cheap. They are considered to be perfectly safe but if you are thinking about purchasing a supplement, it is certainly worth spending the time to research their content as many appear to contain no more than processed corn and vegetables. Whether you feel it is worth spending that money on supplements or try to add more prebiotic fiber diet depends entirely on you.