Bacteria – the good and the bad
The human digestive system is naturally inhabited by billions of bacteria that are collectively called the gut micro flora. You begin acquiring this internal ecosystem in infancy and by the time you’ve reached adulthood, there are as many as five hundred bacterial species and 100 trillion microorganisms in the intestinal tract.
As in most scenarios involving “good and bad”, there is a struggle for dominance. A balance with more of the good, or beneficial, bacteria can have health benefits, including:
- aiding digestion and the absorption of nutrients
- promoting and improving digestive health
- protecting against and fighting infection
- enhance and boost the immune system
- assist in the management of inflammation
When the balance shifts to the bad, or putrefying, bacteria dominating you may see more digestive problems like gas, diarrhea, and constipation.
The balance of bacteria in gut can be thrown to the “bad” by a wide range of circumstance, including:
- Antibiotic use
- Excess alcohol
- Stress
- Disease
- Exposure to certain toxins
Probiotics –
Probiotics are foods that contain these beneficial, living organisms, like the good bacteria.
Probiotics are not new. A clinical account from the 1500s describes King Francis I of France, suffering with diarrhea, being cured only when his physician sent for an Ottoman sultan, who treated the king with yogurt.
Probiotics aid tilting the balance to the good bacteria side, and besides the benefits above, may help:
- Alleviate symptoms of lactose intolerance
- Reduce cholesterol levels
- Decrease the risk of some types of cancer
- Prevent urinary tract infections
- Fight irritable bowel syndrome
Common food sources or probiotics:
- Acidophilus milk
- Buttermilk
- Yogurt
- Fermented foods like sauerkraut, miso, tempeh
- Keifer (fermented dairy product)
- Aged cheeses and some cottage cheese
A word about yogurt…
By definition in the United States, yogurt must contain lactobacillus bulgaricus and streptococcus thermophilus, but some yogurts contain more cultures, or beneficial bacteria.
When buying yogurt, look for “live and active cultures” logo. Some varieties of yogurt are heat-treated to increase their shelf life, but this can kill the probiotics. These products may be “yogurt”, but cannot carry a “live and active culture” seal.
There are at least 6 common live cultures used in yogurts with some “designer” cultures in specific products (like Bifidus Regularis in Dannon Activa). Finding the right product with the right cultures for you may take some experimentation.
| Health Benefit |
Species/Strain |
What it can do for you |
| Healthy gut |
lactobacilli and bifidobacteria |
Healthy gut lactobacilli and bifidobacteria compete against disease-causing bacteria for nutrients and living space inside the intestine. They produce organic acids that help the body fight disease, and even produce natural antibiotics that help discourage the growth of harmful bacteria and other disease-causing substances. |
| Reducing antibiotic-related infections and diarrhea |
L. acidophilus, B longum and S. boulardil |
Antibiotics destroy not only the bacteria causing the infection but also good bacteria inside the body, which can result in diarrhea and yeast infections. Consuming probiotic-fortified foods can help restore the healthy balance of bacteria in the gut and reduce or prevent certain forms of antibiotic-associated diarrhea. |
| Reducing severity of infections |
L. rhamnosus GG |
Studies have shown that probiotics can reduce both the number and severity of primary infections. A double-blind, randomized trial with children in day care showed kids who drank milk fermented with LGG daily had missed significantly fewer days due to illness and had fewer respiratory infections with complications. |
| Boosting the immune system |
L. acidophilus LC1, L. casei and B. bifidum |
Probiotics stimulate the production of immune cells. Probiotic bacteria also suppress inflammatory response and help to control intestinal inflammatory diseases. |
| Helping minimize problems with lactose intolerance |
L. acidophilus, B. bifidus, B. longum and S. thermophilus |
For people who have trouble digesting lactose, fermented milk products such as yogurt are often well tolerated. Fermented foods that contain probiotic bacteria tend to be more effective in easing problems associated with lactose intolerance than probiotic supplements alone. |
Supplements –
Probiotic supplement use is controversial. There is no published evidence that probiotic supplements are able to replace the body’s natural flora when these have been killed off; however, many preliminary studies have been done to support possible benefits. If buying a probiotic supplement, look for the word “uncentrifuged” on the label. The process of being centrifuged can destroy living cells. In addition, capsules are the preferred form for probiotic supplements as it offers the most protection against heat and moisture. A probiotic supplement should have at least 1 billion live cells per gram.
Prebiotics –
Prebiotics are indigestible nutrients that serve as food for probiotics. We don’t digest these nutrients, so they pass through the gut and are fermented in the large intestine by bacteria.
Some natural food sources or prebiotics are asparagus, Jerusalem artichoke, bananas, onions, garlic, leeks, chicory root, wheat bran, oatmeal, flax and barley and resistant starch, found in cooked and cooled starchy foods, like pasta salad.
Prebiotics can also be added to foods in the form of fructooligosaacharrides (FOS), inulin, maltodextrin, lactulose, or polydextrose.
You can find some of the above prebiotics in the following products:
- Kellogg’s Fiber Plus Antioxidant Bars
- Kellogg’s Antioxidant Cereals – Caramel Pecan Crunch and Berry Yogurt Crunch
- Fiber 1 Bars
- Fiber 1 90 calorie bars
- Hy-Vee Fiber Max bars
- Lindsay
