Probiotics are a big and rapidly growing business, with annual global sales of products expected to rise to $42 billion by 2016. The term probiotic refers to dietary supplements (tablets, capsules, powders, lozenges and gums) and foods (such as yogurt and other fermented products) that contain “beneficial” or “friendly” bacteria. The organisms themselves are also called probiotics.
They are promoted to
improve digestion, strengthen immunity, help in weight loss and even protect
against periodontal disease, among other proposed benefits, as well as for
general health. Will the friendly bacteria in these supplements and foods keep
you healthy?
Proponents
claim that probiotics (meaning “for life,” as opposed to antibiotics) confer
health benefits primarily by rebalancing the normal microflora in the large
intestine (colon). There are many general types of bacteria used as probiotics
(two common ones are Lactobacillus
and Bifidobacterium), and many different species as well as strains
within species. They have different physiological effects—and thus possibly
different health benefits (as well as possible risks). Some yeasts, such
as Saccharmyces,
can also act as probiotics.