Most of you have heard the term "probiotics' and some of you may have taken a probiotic supplement after finishing a course of antibiotics. Probiotics contain a selection of micro-organisms that live in our intestines. Our bodies are composed of around 100 trillion cells but around 5-10 times this number of micro-organisms live in our intestines. The total weight of these micro-organisms (or gut flora) is around 4lbs with 500-1000 different species represented in lean, fit, healthy individuals.
Taking antibiotics kills these micro-organisms and changes the nature of the gut flora, producing a dysbiotic state. This is a problem because we now know that this can cause yeast overgrowth, immune problems, weight gain, GI dysfunction (especially constipation) and may also interfere with the production of biotin and vitamin K. A poor diet will also cause a dysbiotic state; in fact it is now being suggested that primitive people still living a traditional lifestyle have a much wider species variety of gut flora than people who have been exposed to a Western diet and lifestyle. Fecal implant therapy (yes...this is EXACTLY what it sounds like!) has been shown to result in weight loss when used in population groups that had a lifelong history of excess body fat.
Many of you will feel the benefits of a probiotic supplement even if you have not recently taken antibiotics. There is a bewildering array of these in the shops so what should you be looking for when you buy? Firstly, look at the ingredients label...if you see a list of chemical preservatives, colourings, flavourings or other "inactive ingredients" then discard that option. Look for products that contain at least 5 different species of bacteria. Remember that your body contains hundreds of different species so there is not much point in taking a probiotic that contains just one or two species.
Lastly, you need to consider dosing parameters. Probiotics usually indicate dosing in CFUs (colony forming units). It has recently been realised that larger doses are often needed to see results. We recommend that you start with 10 billion CFUs per day in two divided doses taken on an empty stomach and gradually build the dose to at least 50 billion CFUs per day (again in two divided doses). Once you have reached the highest daily dose it's a good idea to continue like that for at least 2 weeks. Even 4 weeks at 100 billion CFUs per day would not be over the top in most cases.
If you get any undesirable reactions to the probiotic then consult a health care provider who understands gut function. All of this advice pre-supposes that you eat properly. Please realise that there is no supplement on this earth that will make up for a poor diet.