Should You Take Probiotics?

A review of 45 scientifically-controlled studies published over the last 27 years (European Journal of Clinical Nutrition, March 26, 2018) shows that in healthy people, the use of probiotic supplements can:

• lead to an increase in these healthful bacteria growing in your colon

• reduce belly discomfort caused by irregular bowel movements and constipation

• improve some immune system responses, stool consistency, bowel movements, and the concentration of healthful bacteria in the colon and vagina However, these benefits are only temporary as the bacteria in the probiotics stop growing in the colon or vagina soon after a person stops taking the probiotic product. Permanent changes to a more healthful colony of gut bacteria appear to occur only when you make permanent changes to your diet. The probiotic supplements studied in this review included live healthful bacteria packaged in capsules, powders and liquids or those found in live-culture fermented foods such as yogurt or keffir.

Helpful or Harmful Gut Bacteria Your colon is full of trillions of organisms, some of which are healthful while others can cause disease. The types of bacteria in your colon help to control your immunity, so that healthful bacteria help to protect you from many diseases, while harmful bacteria can increase risk for various diseases. A general rule is that the healthful intestinal bacteria are happy eating the same foods that you do and do not try to penetrate the cells lining your colon, while the harmful bacteria try to penetrate the cells of your colon to invade your body. Your immunity responds by sending cells and chemicals to your colon to try to kill the invading organisms. This is good for you because it helps to protect you from infections, but as soon as an infection is gone, your immunity is supposed to dampen down. If it doesn't, these same cells and chemicals can attack you, punching holes in your arteries to increase risk for heart attacks, damaging your DNA to increase risk for cancer, and causing digestive problems such as irritable bowel syndrome (IBS).

Proposed Benefits of Probiotics Some studies show that probiotic bacteria may reduce high blood pressure, improve blood sugar levels, help to control diabetes, and reduce constipation or diarrhea. However, these claims can be made without good data to prove that healthy people actually benefit from taking probiotic supplements. The issue is further clouded by the harmful legislation passed by Congress in 1994 that keeps the Food and Drug Administration (FDA) from regulating products that are sold as "food". This law means that the FDA cannot protect you from fraud or toxicity unless a large number of people are harmed.

The National Center for Complementary and Integrative Health reports that close to four million adults in the United States take probiotics for weight loss, gastrointestinal conditions, asthma, infections, eczema, depression and various other symptoms, but most of the research has failed to provide data on the possible harms from these products. An analysis of 384 randomized, controlled trials of probiotics (Annals of Internal Medicine, July 17, 2018) showed that:

• 28 percent contained no harms-related data,

• 37 percent had no safety results,

• 80 percent did not include incidence of serious adverse events, and

• 98 percent included no definitions for either adverse events or serious adverse events, patient withdrawals because of these events, or the number of adverse events per study group.

Probiotics are Worthless with an Unhealthful Lifestyle Since bacteria in your colon eat the same food that you do, the best way to grow healthful bacteria is to eat a diet with lots of the foods that encourage the growth of healthful bacteria. Soluble fiber in plants now appears to be the most effective way to grow healthful bacteria in your colon, prevent disease and prolong your life. See The More Vegetables, The Better The number of harmful colon bacteria increases with certain harmful lifestyle factors such as:

• not eating lots of vegetables and fruits

• eating red meat or processed meats

• eating foods with added sugars and other refined carbohydrates

• drinking sugared drinks, including fruit juices

• drinking alcohol

• smoking

• not exercising

• being overweight

• storing fat in your liver Aging also increases the numbers of harmful colon bacteria.

Probiotics May Help to Prevent Overgrowth of Harmful Bacteria When You Take Antibiotics The antibiotics prescribed by your doctor can knock off your good bacteria as well as the bad ones. A review of 39 studies shows that taking probiotics (Saccharomyces, Lactobacilli, Bifidobacteria, and Streptococci) at the same time you take antibiotics reduces a little bit the incidence of diarrhea and super-infections with a harmful bacteria called Clostridia difficile (JAMA, 2018;320(5):499-500).

My Recommendations Since you have no way to know what is actually in probiotic capsules, drinks or other supplement products, I recommend that you spend your money on the foods that are known to help you grow a colony of healthful colon bacteria -- fruits, vegetables, whole grains, beans, nuts and other seeds -- and cut back on meat, sugar-added foods and drinks, other refined carbohydrates, and fried foods. Other lifestyle habits that encourage a colony of healthful gut bacteria are:

• exercising

• avoiding overweight

• avoiding toxins such as alcohol, tobacco, and industrial and home pollutants You may benefit from by taking a probiotic such as live-culture yogurt at the same time you take a prescription for antibiotics to treat an infection.

Checked 1/6/19

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