We are not alone! The average human body contains approximately 30-40 trillion cells, but also about 40 trillion microorganisms including bacteria, fungi and viruses. In fact, there are so many microorganisms in our bodies that they actually make up between one to three percent of our body weight.
For decades, it was impossible to accurately estimate just how many different strains of microorganisms we play host to. A few hundred had been isolated at most. But recently developed genome sequencing methods have enabled the Human Microbiome Project (HMP), in partnership with the National Institutes of Health, to differentiate human and microbial DNA. The facts are now in: more than 10,000 microbial species occupy the human ecosystem.
HMP researchers report that this astonishing variety of microbes contributes more genes to aid human survival than the human body itself. Humans don’t have all the enzymes we need to digest our own diet. Microbes in the gut break down many of the proteins, lipids and carbohydrates in our diet into nutrients that we can then absorb. Moreover, the microbes produce beneficial compounds like vitamins and anti-inflammatories that our genome cannot produce.
We have microbes all over the human body, from the mouth and nose to the intestine, rectum, vagina and even all over the skin. These ecosystems are as different as the desert to the rain forest, so it is not surprising that the microbes are so varied.
Way back in 1906 a French paediatrician noticed breast fed babies didn’t suffer bouts of diarrhoea that formula fed babies did. Treatment with bacteria restored health to the babies with diarrhoea and was the start of using added microorganisms in the form of probiotics to boost the indigenous flora in the body.
Probiotics
Probotics means ‘biological life’ in Greek. Lactobacillus and Bifidobacterium are the most commonly used as probiotics but with over 10,000 different strains to choose from, not all being helpful, it is a challenging task.
Most probiotics do not have to be linked to a prebiotic (more of those later!!) in order to function. Fermented foods are not probiotics per se. To call something a probiotic it has to be isolated and shown to have a benefit in human health in a trial. To do this it has to survive stomach acid and bile, adhere to the cells lining the gut surface and provide antimicrobial action against disease-causing bacteria.
Food sources of probiotics
- Yoghurt and kefir
- Raw cheese
- Kombucha
- Tempeh/natto
The exact mechanism for probiotic function however is not fully understood. It is known that they assist in the production of short-chain fatty acids, lower gut pH, reduce competition for nutrients, stimulate and strengthen the mucosal barrier of the gut and modulate the immune system – not much then!!!!
Health benefits are a very long list from reducing inflammation to lowering the risks of cardiovascular disease and various cancers, there are too many to mention but can also include improving depression and anxiety.
The downsides to taking probiotics are very few – in the early stages as the good bacteria kill off the bad bacteria and ‘die-off’ occurs there can be a short-term toxic effect that can cause diarrhoea/constipation in some patients.
For probiotics to have a health benefit, they must be ingested in sufficient amounts. In most countries, including the US, regulations do not yet require manufacturers to include the amounts of probiotics on the label. In Canada and Italy, however, foods labelled as ‘probiotic’ must contain at least 1 billion colony-forming units (CFUs) of probiotics per serving – that’s the number of living bacteria in the product. If you are looking to take a supplement, aim for a product containing 100 billion CFU’s. Maybe start with 25 million and build up.
Which are better, supplements or food stuff – sorry the research isn’t there!! For me – do the food and if anything in the list below applies to you then maybe take supplements.
So, what are prebiotics?
Prebiotics also have a protective effect, and help safeguard the good bacteria during stressful times. They are the non-digestible fibre compounds that feed probiotics. Eating more prebiotics could undo the damage caused by stress by feeding and nurturing the ‘good’ bacteria in the gut that’s still there.
Prebiotics are in plant fibres, such as raw chicory root, raw Jerusalem artichoke, raw dandelion greens, raw garlic, raw leeks, raw asparagus, and raw and cooked onions.
When should you take probiotics?
- When taking antibiotics
- When under stress
- When travelling
- Possibly taken prophylactically? Not a cure all and if you’re healthy maybe not required but most of us don’t live the ‘perfect’ life so this could be a way of supporting many systems in one go – so what’s not to like!!
