The Power of Probiotics
What are probiotics?
Probiotics – Greek for ‘for life’ – are “living good bacteria” that can improve health. Or, if you want the official definition, “live microorganisms”, which when administered in adequate amounts confer a health benefit on the host. Whichever explanation you prefer the key word is “live” – the bacteria in any probiotic products you take must be alive once they reach the gut to do their job.
Are probiotics new?
Far from it. The idea of health-promoting bacteria was first floated in the 1900s by Russian scientist and Nobel Prize winner, Elie Metchnikoff, who attributed the exceptional health and longevity of Bulgarian peasants to their consumption of fermented milk products such as yoghurt and buttermilk.
Why do we need them?
Your gut, the body’s largest immune organ, is home to 100 trillion good and bad bacteria, known collectively as gut microflora. As well as helping to regulate basic physical functions. such as how we absorb nutrients, a proper balance of good and bad gut bacteria is crucial for immune function.
They could also help as we get older, when age-linked changes in, for instance, what we eat and how long it takes food to pass through the gut, can alter the composition of gut bacteria making us more vulnerable to infection and disease.
Do they work the same for everyone?
Each of us has our own individual gut micro-flora, established in the early years of life, which depends on all sorts of factors including our genes, where we live. our diet and our state of health. This means that a probiotic that helps you may not help someone else. Probiotics are also what is known as strain-specific – that is their benefits depend on the family and type of bacteria used.
How do bacteria become unbalanced?
If you fall ill, have an infection or go on a course of antibiotics, the balance of gut microflora can become disrupted and bad bacteria can outnumber good. Replenishing your gut with good bacteria can restore a healthy balance, which is why in some countries doctors automatically prescribe probiotics at the same time as antibiotics.
How do they work?
Scientists are still working on the exact mechanisms but research suggests that one of the main ways is by regulating the way the cells of the immune system ‘talk’ to each other and carry messages between the gut and other parts of the body and the brain.
What are they good for?
Probiotics have been shown to help shorten the length of infections such as diarrhea and sickness, colds and flu and to prevent and treat antibiotic-associated diarrhea and irritable bowel syndrome (IBS). There is also growing evidence that they may have wider health benefits – from improving digestive health to protecting against inflammatory and allergic diseases, and even preventing symptoms of emotional problems such as stress, anxiety and depression.
What are prebiotics?
Prebiotics are plant fibres – with names such as inulin and fructo-oligosaccharides – found in foods such as fruits and vegetables. Prebiotics provide ‘food’ for probiotics to feed on and as a result can increase their number and efficacy.
How do prebiotics work?
Because they are poorly digested, prebiotics reach the colon intact, where they ferment and act as fuel for good bacteria as well as helping to create an environment that is hostile to the growth of bad bacteria.
What are their benefits?
By boosting the number of good bacteria, prebiotics can increase the bulk and weight of stools, so helping ease constipation. They can improve the body’s uptake of other nutrients. For example inulin helps enhance absorption of calcium, needed for strong bones and other bodily functions. Prebiotics can also boost production of short-chain fatty acids (acids produced from the breakdown of fats), which in turn can benefit immune function, help regulate the metabolism of blood fats, such as cholester¬ol, and may even help prevent some cancers.
The future looks bright. We’ve made huge strides in understanding how probiotics work and exactly what they do to benefit health. We can now screen hundreds if not thousands of bacteria to select them for specific purposes on the basis of sound science.
Thanks to these advances, a new generation of probiotics is on the horizon that could, for example, be used to treat – and even prevent – debilitating inflammatory diseases such as inflamma¬tory bowel diseases, psoriasis and rheumatoid arthritis. These may include or replace the probiotics currently available.
Take probiotics with a cold, not hot, drink as heat destroys bacteria – remember bacteria need to be alive to have an effect…
What are the best food source of probiotics?
Probiotics are found in naturally fermented foods such as cottage cheese, temper, miso, soy sauce, and fresh sauerkraut. You can also get them in live or bio-yoghurts and cultured dairy products such as kefir (a fermented milk drink) and buttermilk. A growing number of products are fortified with probiotics including infant formula, juices and cereals and, of course, you can take them as supplements.
What are the best food source of prebiotics?
Prebiotics are found naturally in a wide range of foods. such as whole grains, asparagus, onions. bananas, garlic. honey, leeks and artichokes. You can also get them in fortified foods such as cereals, biscuits. breads, spreads. drinks and yoghurts as well as taking them in capsules, tablets or powders that you sprinkle on food.
Supplements: how should I take them?
It’s entirely up to you. You can take prebiotics and probiotics as two separate preparations. However you may find it more convenient to take a probiotic with an added prebiotic – the official term is a synbiotic – and these are increasingly available.
Pick and choose
When buying a supplement:
- Check it contains Lactobacilli and/or Bifidobacteria – the types of good bacteria whose benefits have been most studied.
- Make sure it contains sufficient numbers of bacteria – there’s no set number but experts say benefits are rarely seen at less than 100 million bacteria per gram.
- If you are taking a product that also contains a prebiotics, look for one that contains at least 2g per dose – prebiotic doses higher than 20g a day may cause side effects such as wind or bloating.