Probiotics may Prevent Colds

A new study suggests that probiotics, which are beneficial bacteria naturally found in the body and commonly added to cultured milk products, may help prevent cold and flu viruses in children.

There are many different types of probiotics that have various affects on the body. In general, probiotics have been found to help boost the immune system. They may also aid in several gastrointestinal illnesses, such as inflammatory bowel disease, antibiotic-related diarrhea, colitis, infectious diarrhea, hepatic encephalopathy, irritable bowel syndrome and allergies.

Probiotics are thought to work by competing with harmful organisms for nutrients. Some probiotics may also produce substances that inhibit their growth. As a result, probiotics are thought to restore balance to the microorganisms living in the digestive tract.

The latest study, published in the journal Pediatrics, included 326 children from China who were three to five years old. They were randomly assigned to receive milk with probiotics (either Lactobacillus acidophilus alone or in combination with Bifidobacterium animalis) or plain milk twice daily from November 2005 to May 2006.

The researchers report that children who received probiotics developed fewer colds, needed fewer antibiotics and missed fewer days of school than the children who drank plain milk.

Children in the Lactobacillus group developed 53 percent fewer fevers, 41 percent fewer cough episodes and 28 percent fewer runny noses than those in the placebo group. Among those who became sick, length of illness was 32 percent shorter in the Lactobacillus group than in the placebo group. Additionally, the rate of antibiotic use was 68 percent lower and the number of days absent from school was 38 percent lower compared to the placebo group.

These beneficial effects were even more noticeable in those who received the combination of probiotics. These children developed 72 percent fewer fevers, 62 percent fewer cough episodes and 59 percent fewer runny noses. The average duration of illness was also shortened by 48 percent compared to the placebo group. These children were also 84 percent less likely to use antibiotics and 32 percent less likely to miss school than those in the placebo group.

Although these results are promising, the study was funded by Danisco, a Danish company that makes probiotics products. Additional research is needed to confirm these results.

For more information about probiotics please visit Natural Standard's Foods, Herbs & Supplements database.

Comments

[John KJ]

This study is a very interesting trial evaluating the effects of probiotics in children. The study suggested that probiotics reduced the severity and duration of cold. Probiotics also reduced the use of antibiotics significantly.

This would be an important area for further studies since reduction in the use of antibiotics could reduce microorganisms’ resistance to treatments. The development of resisting MOs, such as MRSA, is one of the most concerning issues. If we can limit the use of antibiotics, chances of resistance will lessen.

[nick]

I agree with the author that the study should be repeated with an unbiased company. When it is redone, it would be interesting to also have the study done in various age groups. For example, probiotics do not appear to have as overwhelmingly conclusive results in adults as they do for children in this study, so it would be interesting to see it redone with children and adults in the same study to see if both groups received similar results. Or even in teens?

[I Love Activia]

I am a strong supporter of probiotics and all of the positive health benefits they have. I also would not be surprised if they helped improve colds, although from my understanding, they mostly replenish the flora in the gut, not the lungs. I would be interested to learn more about the proposed mechanism of how they could prevent or improve a cold.

I do have to say though, this study that Natural Standard is writing about has little relevance to the population here, as it was done on children in China --- who most likely get different strains of the common cold. I would be interested to see further research on this topic and on other health benefits of probiotics.

[MM]

Companies that sponsor studies that are of obvious benefit to them must expect the backlash of bias, as in this case. I suppose they proceed hoping their results will spur more independent research?

On another note, I hope someone can comment on HOW the probiotics are put into these dairy products. Or more precisely, where are they produced to be put in foods? How are they grown? Where are they extracted from? I'd welcome some information on this!

[JH]

For the prevention of colds and bacterial infections in children, these results are very impressive. But children are going to get sick no matter what just because they’re always around each other and touch everything without ever washing their hands. That’s just part of childhood. When further research is conducted, it may be more useful to study specific populations of children who are at high risk of getting infections, rather than healthy children. And since probiotics are known to be useful in maintaining and restoring gastrointestinal health, a prospective study that follows healthy children into teen years and early adulthood could shed some light on prevention or risk factors for irritable bowel syndrome and other disorders.

[lauri]

I found this site that discusses some interesting information on probiotics in yogurt. Good to know that not all yogurt contains active cultures! The site also has some great info on which cultures are in what products, etc.

"In the United States, yogurt is required to be produced by the fermentation by Lactobacillus bulgaricus and Streptococcus thermophilus. However, post-fermentation heat treatment of yogurt, which kills all live cultures, is allowed. To help consumers distinguish between yogurts that contain live active cultures and those that do not, the National Yogurt Association established a 'Live Active Culture' seal. The seal is available for use by any yogurt manufacturer on packaging and requires refrigerated yogurt to contain 108 viable lactic acid bacteria per gram at the time of manufacture. The seal also can be used on frozen yogurts containing 107 viable lactic acid bacteria per gram at time of manufacture. However, these counts do not differentiate probiotic bacteria from starter culture bacteria (L. bulgaricus and S. thermophilus), and therefore, the seal is not useful in determining if adequate levels of added probiotic bacteria are present in a yogurt. In other words, the standard refers to a total number of live cultures, and levels of each microbe present do not have to individually meet the standard."

Sanders, 2007. http://www.usprobiotics.org/products.asp

[Tim M]

I think MM makes a very good point. In order for a study to start, it initially has to be funded by a company that produces the product that is test. Then, after it gains interest, there will be some outside funding.

What I want to know is how probiotics would compare to CAM therapies that are currently used for colds. I know products like Echinacea and vitamin C have controversial studies, but they are still being use for colds. I want to know how these products would do compared to probiotics.

[ghg]

The information on probiotics from Natural Standard's Web site states that probiotics help to maintain normal bacterial flora of the intestinal tract and aid in digestion. It furthermore explains that probiotics are thought to work by colonizing the small intestine and crowding out disease-causing organisms, thereby restoring proper balance to the intestinal flora. I am interested in finding out how this mechanism helps prevent colds in children.

[Jasmine]

Probiotics are also called friendly germs, as they are beneficial bacteria. Most probiotics come from food sources, especially cultured milk products. It comes in many different formulations, and the most common of them is yogurt, while other formulations are capsules, tablets, beverages, powders and other foods. They help with digestion and help the body maintain a healthy intestine. One other advantage is that they also help keep harmful bacteria and yeasts in the gut under control.

[Julie]

One thing that really stuck out to me while reading this post is that the study had antibiotic use as one of its measurable outcomes. I do not think that antibiotic use is a good indicator of whether a child has a cold or not because the common cold is caused by a virus, most commonly the rhinovirus or influenza virus. Thus, to use an antibiotic (a drug that only kills bacteria) to treat the common cold (caused by a virus) is bad clinical judgment.

Unnecessary antibiotic use can actually cause more severe bacterial infections to surface because bacteria develop resistance to antibiotics when they're prescribed to children with viruses. I think that this study points out one of the serious problems with current pediatric primary care – antibiotic overuse. Antibiotics should be reserved for only bacterial infections, such as sinus or ear infections, strep throat, etc not colds. If antibiotics are used unnecessarily, then when children actually do have bacterial infections, they will be harder to treat, especially if it is a more serious infection. I think it would be a good idea for parents to recognize that common colds can be managed adequately with fluids, rest and symptom management.

[brianna]

I’ve heard that probiotics may also aid in inflammatory bowel disease, (including Crohn’s disease, and ulcerative colitis). Has anyone known anyone who has tried them and had it be efficacious? I know they have minimal clinical evidence for these disease states, but I’ve heard a couple people say they’ve worked wonders.

[jag]

Has anyone ever tried the probiotic yogurts, or other food products? I’m wondering if they taste the same as “regular” yogurt or not. I’d also be curious to see if the milk in this study tasted different and if the kids would be more or less likely to drink it.

[Steve]

I agree with JH in saying that colds are a part of childhood. I disagree with the use of probiotics for cold prevention in children. Although getting a cold is not the most comfortable thing, staying away from all kinds of illness does not exactly help build up our immune response. Fighting off an infection is the function of our immune system, and it tells us that our immune system is doing its job. If we are exposed to pathogens when we are younger, it's more likely that our bodies will recognize and attack the pathogens in the future. Maybe these little colds are what we need to prepare our bodies to fight major health threats in the future.

[Buggie]

Is it possible that the differences in diet between Chinese children and those from other nations could play a factor in determining the composition of their natural flora? If so, then I would imagine the addition of probiotics would have varying effects on the overall health of children depending on their baseline bacterial compositions. It would be interesting to see more studies completed in other areas of the world where diets vary.

Another point is that the months of November to May cover flu season in the Northern Hemisphere, but the Southern Hemisphere experiences flu season in the opposite months.

[Joey]

In response to Jag’s comment posted on August 13th, I’ve tried the Activia yogurt, and I find it to be less sweet tasting than regular yogurt. It used to come as 6 multi-flavor cartons per pack, but now it comes as 4 single-flavor cartons. It also can be categorized further based on its texture: fruit, fiber, and smooth. Overall, I don’t find much of a difference in the way Activia tastes from regular yogurt, and I imagine that other probiotic-containing milk products would show similar outcomes.

[rgorensh]

Not to belittle probiotics, which I’m sure are great for us (and who doesn’t love those Activia commercials with Jamie Lee Curtis), but the fact that the company that makes them sponsored the study taints the results somewhat. On the other hand, these results do look quite promising, so I hope more studies are done by independent agents to support the claim that Lactobacillus acidophilus reduces the number of colds and the need for antibiotics in children. (Probiotics reduce the need for antibiotics. Rather ironic, isn’t it?) Then again, if probiotics already have been shown to boost the immune systems, doesn't it already mean fewer colds?

[louise]

Assuming that many more studies support these initial findings (that probiotics reduce the number of colds in children, reduce the use of antibiotics, and help manage other disease states), how would the public feel about including probiotics in all milk products? Fluoride is automatically added to public water sources because its dental benefits have been proved, and it’s made available to all socioeconomic classes through this method. Should probiotics be treated any differently if they are a cost-effective measure at preventing illness and assisting with other medical conditions? Personally, I believe that it should be my choice on whether I want a particular substance added to my food. However, if future evidence shows that the addition of probiotics to milk sources will drastically help reduce healthcare costs (not only in children, but the entire population), then I can potentially see our freedom of choice getting pushed aside.

[Cheryl]

Probiotics are thought to strengthen the immune system, so that would be a plausible reason why children had fewer fevers, cough, and runny noses when taking them. But, those are also very generic symptoms, and it is thought that the common cold is caused by several viruses. Could it be that these probiotics have some kind of activity against these common viruses?

[hg]

In response to Brianna, I know one person who uses probiotics along with other medications for the treatment of Crohn’s disease. Probiotics seem to be thought of as a safe supplement to keep the stomach regulated, but I would always recommend discussing the use of probiotics for a medical condition with a physician or pharmacist to see if it is an appropriate option.

[mj]

If putting probiotics in milk does become the “norm,” I agree with previous posts that long-term side effects are going to be an issue. No one will argue that numerous chronic digestive diseases have become more prevalent here in the U.S., and there are many theories that say it is because we are too clean and are not exposed to enough bacteria as children. While this may be great for the short-term reduction of colds, it might be something we don’t want to mess with in children.

[jake]

Also, if we begin adding probiotics to milk, I wonder what this will do for the cost of the milk. Obviously, it will go up, but I wonder if it would be enough to make it so consumers wouldn’t buy it in this economy.

[matthew]

I’m sure probiotics have to be taken ahead of time to see any effect, but how far ahead? Is it something we should take year-round or just when we feel a cold coming on? Should we be recommending probiotics during the cold season, like when we give out flu shots?

[Lee]

Colds are one of the leading causes of doctor visits and missed days from school and work. According to the Centers for Disease Control and Prevention (CDC), 22 million school days are lost annually in the United States as a result of the common cold. Over the course of a year, people in the United States suffer one billion colds, according to some estimates. It is estimated that the average person contracts more than 50 colds during a lifetime. Anyone can get a cold, although preschool and grade-school children catch them more frequently than adolescents and adults. The most common cold-causing viruses survive better when humidity is low during the colder months of the year. Cold weather also may make the inside lining of the nose drier and more vulnerable to viral infection. According to a Natural Standard monograph, there is a lack of sufficient evidence that probiotics help prevent colds.

[June]

I think this study is a well-designed trial that included a big study group over a six-month period during the peak flu season. I am surprised to see such a significant effect though, seeing a range of 40 to 60% reduction in fevers and colds. I am really interested to see another study done that's not funded by the probiotic company to see if similar effects can be repeated.

[sk]

Probiotics are generally known for promoting GI balance and health. Their role in preventing colds has never been examined until now. The authors didn’t mention how probiotics may help prevent colds, but it is very interesting since probiotics promote health bacterial flora and colds are caused by viruses. I think the mechanism by which probiotics may help prevent colds might actually be an indirect effect. Since colds are caused by viruses, probiotics may help promote bacterial flora that compete against viruses or they may promote an environment that prevents viral attachment. Another mechanism might be that probiotics may improve or strengthen the immune system by promoting a health GI tract. More research is needed with probiotics, and this finding gives additional reasons for taking probiotics!