The pros of probiotics

Gemma Dunkley

What are probiotics and prebiotics?Probiotics are live beneficial micro-organisms — such as bacteria, yeasts and fungi. They help to balance the bacterial population of the gut. The most commonly used probiotics are lactobacillus and bifidobacterium bacteria as these survive passage through the gut. Probiotics are available in yoghurts and fermented dairy drinks (e.g. Yakult) as well as in tablet, capsule and powder forms.

Prebiotics are food ingredients that help to feed good bacteria in the gut and increase their activity. Prebiotics occur naturally in bananas, asparagus, leeks, onions, garlic, chicory and whole-grains like wheat, rye, barley and oats.

Who needs probiotics?Your digestive system contains over 1.5kg of micro-organisms or 100 trillion bacteria. It may sound like an exaggeration, but it’s true, and of the 100 trillion bacteria inside us, there are over 100 different types. Some of these are helpful to our health and some are harmful. The trick is to get the balance right.

In most people the correct balance of friendly bacteria is maintained in the digestive system by eating a healthy, well- balanced diet, and taking extra probiotics is not necessary.

However, ageing, climate, stress, unhealthy food, alcohol, illness, infection and some medications can alter the bacteria in your gut, increasing the bad bacteria and reducing the good. In this situation, probiotic products that contain live bacteria, that survive digestion, will help restore the balance of friendly bacteria living in your digestive system.

Probiotic benefitsTo date, the strongest evidence for the use of probiotics is for shortening the duration of diarrhoea and for restoring the balance of bacteria in the gut after using antibiotics. Taking antibiotics can cause bad bacteria to outnumber good bacteria in the gut. When this happens bloating, cramping, gas and diarrhoea can result. Taking probiotics helps reduce the number of harmful bacteria and can help the breakdown of waste passing through the gut.

Probiotics have recently been connected to improving immunity. As they help to maintain a healthy balance of bacteria in the gastrointestinal tract (where approximately 70 percent of the immune system is found), this is thought to stimulate the actions of the immune system.

There is also some evidence that probiotic use may be beneficial for respiratory and urinary tract infections, irritable bowel syndrome, inflammatory bowel disease, ulcerative colitis, and certain types of cancer (bladder and bowel). However, these are emerging areas of research and no clear guidelines are currently available.

Getting specificAccording to the International Scientific Association for Probiotics and Prebiotics, the type of health benefit and amount of probiotics needed to achieve any benefit is strain-specific. Products claiming to be probiotic (e.g. yoghurt) should define the type of probiotic they contain (e.g. Lactobacillus) and the amount of probiotics (e.g. 1 million live bacteria/gram). Unfortunately, currently in scientific studies, product regulations and advertising, this information is often lacking. Additionally, the bacteria in products should be alive, but several recent studies have found that they are not.

A healthy dietIf you are healthy and follow a well-balanced diet, enjoying food from the five food groups — with plenty of wholegrain breads and cereals and plant foods (fruit, vegetables) as well as some dairy and meat/meat alternatives — probiotics aren’t necessary.

There is currently not enough evidence to prove that probiotics improve your general health if you take them all the time. However, if you do want to use probiotic products (e.g. yoghurt or supplements), they are generally safe to use. (Probiotics are not advised for people with severe illnesses or who are immuno-compromised.)

Gemma’s Top tipsIf you want to buy probiotics, to ensure you are getting the most for your money, here are my top tips:

• Check use-by date on probiotics — the fresher the better. The shelf life of most probiotics is three to six weeks and no more than 12 months for tablets. Avoid products not stored as recommended (e.g. not refrigerated)

• Probiotics need to be alive — so look for “live and active cultures”. Avoid products saying “made with active cultures” — these are often heat-treated, which kills bacteria.

• One of the most important things about taking probiotics is that quantity does count. Any product claiming to be probiotic must contain at least one million bacteria per gram (10 million is best).

• If possible, choose products that name the genus (eg. Lactobacillus), species (eg. rhamnosus) and even the strain (eg. GG).

• Make sure the product has been tested in scientific trials i.e. “clinically proven”.