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There are many reasons to start taking daily probiotics for men’s health. More and more research is coming in about how probiotics are beneficial to all aspects of health from prostate health to digestive health to better immunity.
1. What Are Probiotics?
Probiotics, also referred to as beneficial bacteria, friendly bacteria, good bacteria, and beneficial gut microflora, are microorganisms that reside in the gut (alimentary canal). That includes the pathway that runs from the esophagus to the anus. Beneficial bacteria are found primarily in the intestines and are part of the intestinal flora.
The largest group of beneficial bacteria in the gut are those in the genus Lactobacillus, followed by Bifidobacterium. Each of these groups has scores of species and subspecies, and researchers are still exploring the traits and benefits of these microorganisms.
Long before researchers began to understand the scientific basis behind the benefits of probiotics, various societies were enjoying foods that provided these beneficial bacteria in the form of fermented foods and beverages, all of which are still available today.
The ancient Romans ate sauerkraut while members of ancient (and contemporary) Indian society enjoyed a raw yogurt beverage. A variety of fermented vegetables have been a popular part of Asian culture for millennia while Bulgarians and people of the Ukraine make fermented dairy beverages a part of their regular diet.
Beneficial bacteria received some scientific recognition in the early 1900s, but a better appreciation of the health benefits did not occur until many decades later, partly because they are a natural substance and not a profitable product for the pharmaceutical companies, who were busy introducing many new drugs to the market. In recent years, research on probiotics has been brisk and an appreciation for these good microorganisms has been growing.
About Good Bacteria
Lactobacillus, as well as the genus Streptococcus and Lactococcus, are known as lactic acid bacteria. These beneficial bacteria help break down food, and in the process form lactic acid and hydrogen peroxide, which in turn helps eliminate bad bacteria and help restore balance to the gut. They also are critical in promoting digestion, nurturing immune system function, boosting the synthesis of B vitamins, and aiding in the absorption of nutrients (including calcium).
Bifidobacterium species also produce lactic acid but can be beneficial in some different ways. Generally they support the immune system, help reduce cholesterol levels, fight allergic reactions and infections, aid in digestion, and have some anticancer properties. Therefore you can see why it can be beneficial to provide your body with both Lactobacillus and Bifidobacterium species of probiotics.
Good health depends on your having a healthy balance of friendly bacteria in your gut to offset the negative effects of the harmful microorganisms that also reside there. Your gut is a critical key to optimal health because 70 to 80 percent of the cells that make up your immune system are located in the walls of your gut. (Johns Hopkins) Therefore, if the population of beneficial bacteria in your gut is reduced or compromised because of illness, stress, or the presence of toxins (including medications such as antibiotics), it’s important to replenish the levels of good bacteria and restore balance to the intestinal tract.
“..70 to 80 percent of the cells that make up your immune system are located in the walls of your gut..”
At the same time, maintaining a healthy balance of intestinal flora is important 24/7, every day of your life. Approximately 500 different types of probiotics have been identified, and experts continue to explore their activities and benefits. What we do know is that while you should take steps to correct occasions when your beneficial bacteria levels are jeopardized, it’s also essential to maintain healthy levels of beneficial bacteria all the time since as a group they play a critical role in maintaining overall health, including prostate health.
Where to Get Probiotics
The two sources of probiotics: foods and supplements. Foods that contain them include fermented vegetables (such as sauerkraut, kimchee), yogurt, kefir, buttermilk, and items that are enriched with good bacteria. Although it is suggested you include these foods in your diet, they often do not contain a significant amount of active bacteria, especially if the products have been pasteurized or otherwise processed, as these methods can kill the beneficial bacteria.
The other option is high-quality probiotic supplements from reputable manufacturers. You should look for products that offer a variety of well-researched species to help ensure you replenish and restore a healthful balance of bacteria in your gut for overall health and prostate health in particular.
2. The Second Brain and the Gut-Brain Connection
Scientists have announced that humans have two brains, and probiotics play a significant role in both of them. The second brain is actually known as the enteric nervous system and is found in your gut. More specifically, it is made up of groups of neurons living in the walls of the nine meters that make up your gut, from your esophagus to your anus. This second brain contains more neurons than your spinal cord or your peripheral nervous system. In fact, the second brain contains 95 percent of the serotonin in your body (the neurotransmitter also in your other brain that is responsible for mood and some behaviors).
The two brains communicate by sending signals via the vagus nerve, the super highway that runs between the head brain and the stomach. The second brain contains more than two dozen other neurotransmitters also present in the head brain. (Hadhazy)
Research thus far into the gut-brain relationship has suggested that taking probiotics can have a positive effect on behavior, mental outlook (i.e., depression, anxiety), and brain function. One such study was done in a group of 36 healthy women who were divided into three groups. One group consumed yogurt containing probiotics for 4 weeks, one ate yogurt without probiotics, and one was a control. The probiotics included L. bulgaricus, L. lactis subsp Lactis, B. animalis subsp Lactis, and S. thermophiles.
“…taking probiotics can have a positive effect on behavior, mental outlook (i.e., depression, anxiety), and brain function..”
After undergoing magnetic resonance imaging (MRI) of the brain and participating in emotion recognition tests, the researchers found that women who regularly ate yogurt with probiotics showed positive changes in brain function related to emotions and sensory processing. (Tillisch)
As a group of experts have noted in a series of recent articles in Gut Pathogens “despite the advances in the area of gastrobiological psychiatry, it becomes clear that there remains an urgent need to explore the value of beneficial microbes [i.e., probiotics] in controlled clinical investigations.”
3. Benefits of Probiotics for Men’s Health
Ongoing research shows that probiotics can be effective in managing a wide range of health problems that affect men. Here are some examples.
Inflammatory Bowel Disease
Selected probiotics may help prevent relapse of Crohn’s disease and support remission of ulcerative colitis, the two primary types of inflammatory bowel disease. In a systemic review of 41 studies, an investigative team found that a combination of eight different strains of probiotics (B. breve, B. longum, B. infantis, L. acidophilus, L. plantarum, L. paracasei, L. bulgaricus, and S. thermophilus, collectively known as VSL#3) was helpful in inducing remission in ulcerative colitis and in preventing relapses in patients with inactive ulcerative colitis and pouchitis. Two studies showed some benefit by preventing recurrences in inactive Crohn’s disease when patients took L. rhamnosus GG versus placebo. (Jonkers)
Diabetes and Alzheimer’s disease
Some experts have suggested that changes in the microflora in the gut have a role in the development of diabetes and Alzheimer’s disease (which is sometimes referred to as type 3 diabetes). That’s because alterations in gut bacteria along with certain dietary habits can cause toxins to leak out of the intestinal tract (called leaky gut), cause inflammation, and eventually result in insulin resistance, a risk factor for diabetes and Alzheimer’s disease.
In addition, changes in gut bacteria have been associated with obesity, another risk factor for diabetes. These relationships suggest probiotics could play a significant role in the development and management of diabetes and Alzheimer’s disease. (Bekkering)
Irritable Bowel Syndrome
In a recent review of the use of probiotics for irritable bowel syndrome, the authors pointed out that while studies indicate the beneficial bacteria are helpful in treating this syndrome, it also seems that probiotics are more effective at resolving single symptoms rather than the syndrome as a whole. Certain strains of Lactobacillus and Bifidobacterium have been shown to improve stomach pain, bloating, and other symptoms of irritable bowel syndrome. In fact, the same combination of probiotics shown to be effective in relieving symptoms of inflammatory bowel disease (B. breve, B. longum, B. infantis, L. acidophilus, L. plantarum, L. paracasei, L. bulgaricus, and S. thermophilus, collectively known as VSL#3) has also helped patients with irritable bowel syndrome. (Dai)
Stomach ulcers are often caused by the bacteria Helicobacter pylori, and this is good news because there are effective ways to treat this gastrointestinal condition that includes probiotics. Research indicates that probiotics, when used along with therapies such as levofloxacin, various quinolones, and bismuth, can help reduce side effects and improve compliance. (O’Connor)
Certain probiotics have been shown to help in the management of infectious diarrhea in infants and children, but less so in adults. However, adults who develop diarrhea associated with the use of antibiotics can get relief from taking probiotics. This is especially important for men who are prescribed antibiotics to treat bacterial prostatitis or a urogenital infection.
A review in the Journal of Clinical Gastroenterology reported that the most commonly used probiotics to treat antibiotic-associated diarrhea in both children and adults are L. acidophilus, L. casei, Bifidobacterium species, and Streptococcus species, among a few others. The good news is that most of the studies showed “clear evidence of efficacy.”
In a subsequent meta-analysis of 63 clinical studies that involved more than 11,800 patients, the authors concluded that use of various species of Lactobacillus resulted in a 36 percent reduction in the occurrence of diarrhea among individuals taking antibiotics. (Hempel)
Yet another meta-analysis study showed promising results in the prevention of Clostridium difficile-associated diarrhea among patients treated with antibiotics. A total of 20 trials that involved 3,818 individuals were reviewed, and the authors found that even though some data were missing from several of the trials, overall the use of probiotics reduced the incidence of diarrhea by 66 percent, and there were no significant side effects associated with the beneficial bacteria. (Johnston)
Further evidence of the benefits of probiotics in the prevention of diarrhea associated with the use of antibiotics can be found in a study that used a probiotic beverage containing L. casei, L. bulgaricus, and Streptococcus thermophilus. The 135 older adults (average age, 74) were all taking antibiotics and were given either the probiotic-rich beverage twice a day during treatment and for one week after the antibiotic course was finished, or a placebo.
Diarrhea developed in 12 percent (7 of 57) of patients who took the probiotic beverage compared with 34 percent (19 of 56) of those who took the placebo. None of the patients in the probiotic group and 9 (17%) in the placebo group had diarrhea caused by C. difficile. Overall, these three probiotics helped reduce the incidence of antibiotic-associated diarrhea and C. difficile associated diarrhea in older adults. (Hickson)
Among the most recent studies of the benefits of probiotics for prevention of antibiotic-associated diarrhea is an international study appearing in Vaccine. The 503 patients taking antibiotics were randomly assigned to one of three groups: high-dose of a proprietary probiotic formula containing 4 strains (L. acidophilus, L. paracasei, and 2 B. lactis strains), low-dose of the formula, or placebo. Use of the probiotics or placebo continued throughout antibiotic treatment and for seven days after the course was completed.
The incidence of diarrhea was 12.5 percent, 19.6 percent, and 24.6 percent among those taking the high dose, low dose, or placebo, respectively. Bloating, abdominal pain, fever, duration of diarrhea, and number of daily liquid stools declined with the increasing dose of probiotics. Incidence of C. difficile-associated diarrhea was 1.8 percent in both probiotic groups and 4.8 percent in the placebo group. Overall, the probiotic supplement lowered the risk of antibiotic-associated diarrhea and gastrointestinal symptoms, with better results seen at the higher dose. (Ouwehand)
Diarrhea Related to Chemotherapy
Men who are receiving chemotherapy for prostate cancer or other cancers run the risk of developing diarrhea as a side effect of treatment, especially if they are given 5-fluorouracil. A study in the British Journal of Cancer reported that patients with colorectal cancer who were treated with 5-fluorouracil and who also were given L. rhamnosus GG experienced less severe diarrhea, less stomach problems, and had a shorter hospitalization than patients who did not take the probiotic. (Osterlund)
For people who experience symptomatic uncomplicated diverticular disease, use of probiotics (L. casei subsp. DG) has been shown to be as effective as the prescription medication mesalazine. In a double-blind, placebo-controlled study, 210 individuals were treated with either mesalazine plus probiotic placebo, L. casei plus mesalazine placebo, mesalazine plus L. casei, or two placebos. All the treatments were continued for 10 days per month for one year.
None of the patients in the L. casei plus mesalazine group experienced a recurrence of the disease while nearly half (46%) of those in the double placebo group did. The recurrence rates in the mesalazine plus probiotic placebo group and the L. casei plus mesalazine placebo groups were similar (i.e., 13.7% and 14.5%, respectively). The conclusion was that L. casei is as effective as mesalazine in the treatment of symptomatic uncomplicated diverticular disease, and that the combination of treatments works best. (Tursi)
Evidence that beneficial bacteria play a significant, even critical role in the integrity of the immune system is accumulating. For example:
A November 2013 study published in Nature reported that probiotics have a role in the maturation of the immune system. After the bacteria digest fiber in the intestinal tract, a byproduct (butyrate) of that action sets off activity that produces important immune cells (regulatory T cells), which in turn boost the health of the immune system. Thus two important benefits are seen here: butyrate has anti-inflammatory properties and the regulatory T cells that it promotes also help control inflammation. (Furusawa)
“introducing friendly bacteria in the form of probiotics is believed to challenge the immune system in healthy ways.”
According to Stefano Guandalini, MD, professor of pediatrics and gastroenterology at the University of Chicago Medical Center, probiotics are useful for maintaining a strong immune system. He explains that “introducing friendly bacteria in the form of probiotics is believed to challenge the immune system in healthy ways.” (WebMD)
Cold and Flu
If you are looking for help in preventing or at least reducing the effects of the common cold or flu, probiotics can help. Two probiotics—L. plantarum HEAL 9 and L. paracasei 8700:2—were evaluated in a double-blind, placebo-controlled trial that involved 272 adults. One billion CFUs of the probiotics were given to 135 participants while 137 were administered a placebo during the 12-week study. The risk of experiencing one or more episodes of the common cold were reduced from 67 percent in the placebo group to 55 percent in the probiotic groups. Individuals who took probiotics had cold symptoms for an average of 6.2 days while those in the control group had them for 8.6 days. Use of probiotics was also associated with a significant reduction in sore throat and other throat symptoms. (Berggren)
“Individuals who took probiotics had cold symptoms for an average of 6.2 days while those in the control group had them for 8.6 days”
Losing weight can be a challenge, and probiotics could help get over the hurdles. In a 2013 study, the effect of L. rhamnosus CGMCC1.3724 on weight loss and maintenance was analyzed in a double-blind, placebo-controlled study involving obese men and women. During the 24-week trial, participants took either the probiotic supplements or placebo and also followed a specific calorie-restricted plan (500 less calories per day for 12 weeks) and a maintenance eating plan (subsequent 12 weeks).
During the first 12 weeks, the average weight loss among women who took the probiotic was 9.7 pounds compared with 5.7 pounds among those who took placebo. Women in the probiotic group continued to lose weight (average of 1.3 pounds) during the next 12 weeks while women in the placebo group did not.
Among the men in the study, weight loss averaged 9 to 10 pounds in both the probiotic and placebo groups during the first 12 weeks and about an additional 2 pounds during the second 12 weeks, again in both groups. Although this study did not show an advantage for men taking probiotics for weight loss, further research may yield more promising results for men. (Sanchez)
It should come as no surprise that mood disorders such as anxiety are associated with probiotics once you know that about 90 percent of the serotonin in the body is found in the gut as well as about 50 percent of the body’s levels of dopamine. People who suffer with chronic gut problems are at greater risk of experiencing psychological problems. Since both serotonin and dopamine levels play a significant role in mood disorders, a relationship between probiotics and psychological conditions seems apparent.
So far, research into this relationship has been limited. However, an animal study attempted to study the association by giving B. longum to mice with gut inflammation who also exhibited anxiety behavior. After the mice received 1 billion cells of the probiotic for one week, they stopped their anxious behavior, although there was no improvement in their inflammation. The authors noted that the probiotic seemed to calm the excited nerves that connect the gut with the central nervous system via the vagus nerve, which is part of the brain-gut connection. (Bercik)
In a double-blind, placebo-controlled study, researchers used human volunteers to test the impact of L. helveticus and B. longum on anxiety and depression. The participants took either the probiotic supplement or placebo for 30 days and were evaluated using various standard psychological tests. The investigators reported that use of the probiotics resulted in “beneficial psychological effects” in the healthy volunteers. (Messaoudi)
4. Probiotics to Look for in a Quality Probiotic Supplement
You want to find a quality probiotic supplement that has certain strains of beneficial bacteria. Generally, all of the probiotics in this supplement help support and nurture the immune system, aid in the digestive process, and have a role in nutrient absorption. In addition, some of the beneficial bacteria have been shown to provide other advantages. Ingredients to look for present in a quality supplement include the following.
L. acidophilus is probably the most recognized of the beneficial bacteria and probiotic supplements on the market. It is typically one of the beneficial bacteria found in probiotic supplements and foods containing friendly bacteria. This Lactobacillus species produces an enzyme called amylase which helps digest carbohydrates. In addition to the usual benefits associated with probiotics, L. acidophilus helps prevent antibiotic-associated diarrhea and lactose intolerance.
Lactobacillus brevis has been found to possess anti-inflammatory and possibly anti-cancer properties. Evidence of its anti-inflammatory activity was noted in a study of L. brevis lozenges in patients who had oral ulcers associated with Behcet’s syndrome. (Tasli) The possible anti-cancer activity was seen in animals who showed a significant suppression of tumor formation and a decline in DNA damage after they were given the probiotic. (Ljungh)
Lactobacillus bulgaricus plays several roles in the digestive tract. One is to release substances that can alter the pH of the gastrointestinal tract, which in turn destroys various pathogens. These beneficial bacteria also have an ability to stop pathogens from sticking to the intestinal wall, which helps prevent infection and disease. Yet another activity is the excretion of natural antibiotics, which helps boost immune function.
Some research in rodents suggests this probiotic may have some anti-tumor properties. (Baricault)
Lactobacillus rhamnosus, often referred to as L. rhamnosus GG (the “GG” stands for the last names of the scientists who first isolated it) is especially valued for its ability to help support the immune system and digestive tract and fight intestinal and urinary tract germs. This probiotic is usually included in yogurt products as a natural preservative because it nurtures the growth of beneficial bacteria that help with digestion.
L. rhamnosus is highly tolerant of high acid levels in the digestive tract and is also bile-stable, characteristics that make it efficient in fighting intestinal infections. The probiotic also has demonstrated an ability to help prevent some urogenital infections in women, although the evidence concerning urinary tract infections is less convincing. (Abad; Beerepoot)
Lactobacillus casei complements the growth of L. acidophilus, which is why it is frequently taken along with this other beneficial bacteria. In addition, L. casei is often combined with other probiotic strains to help with management of antibiotic-associated diarrhea.
Lactococcus lactis is used primarily in the production of cheese and buttermilk and is considered one of the most important microorganisms by the dairy industry. Live L. lactis bacteria can produce proteins that in turn reduce inflammation.
Lactobacillus paracasei has demonstrated an ability to reduce gastrointestinal symptoms. This probiotic also has been shown to assist in fighting symptoms of the common cold.
The added benefits of B. longum include an ability to help prevent antibiotic-associated diarrhea and anticancer properties. In the latter case, a study in rats with colon cancer showed that the beneficial bacteria prevented the spread of cancer and stopped the tumors from growing. (American Health Foundation) B. longum also may reduce lactose intolerance symptoms and lower cholesterol levels.
Bifidobacterium bifidum are beneficial bacteria that have been studied most extensively for their role in fighting health problems in infants and young children, because they have shown themselves to be effective in improving the immune response in these highly vulnerable individuals. These beneficial bacteria also have demonstrated an ability to fight allergic diseases such as eczema in the same population. Despite the lack of research into the effects of B. bifidum in adults, it seems clear from studies in young people that this probiotic could provide benefits for other ages as well.
B. bifidum also has shown an ability to help lower cholesterol. A rat study was conducted recently to determine the impact of certain Bifidobacterium species on cholesterol. A combination of B. bifidum, B. breve, and B. animalis subsp. lactis resulted in a significant reduction in total cholesterol and bad (LDL) cholesterol. (Bordoni)
Streptococcus thermophiles has an ability to prevent the conversion of nitrates into nitrites, which have cancer-promoting properties. This trait plus others have led scientists to test the probiotic in numerous cancer studies in animals.
One of those studies looked at the use of S. thermophilus in rats with mucositis (inflammation of the intestinal tract) caused by chemotherapy drugs. When the animals were given the beneficial bacteria, they showed normalization of healthy cell function and improvement in their intestinal tract. (Whitford)
S. thermophiles also may help with high cholesterol. For example, researchers conducted a meta-analysis of six studies of the impact of a probiotic milk product (yogurt containing two strains of S. thermophiles) on cholesterol levels. They found that individuals who consumed the yogurt experienced a 4 percent decrease in total cholesterol and a 5 percent decrease in bad (LDL) cholesterol. (Agerholm-Larsen)
5. Probiotics and Prostate Health
Probiotics may have a role in preventing and managing common prostate conditions; namely, prostatitis and benign prostatic hyperplasia. They even may have a part in the treatment of prostate cancer. The main reason this is true is because these beneficial bacteria are immensely important in immune system function and in controlling inflammation, a key factor in BPH, prostatitis, and prostate cancer.
Prostatitis is a prostate condition characterized by inflammation of the prostate, pain, and a variety of urinary symptoms, such as urinary frequency, urgency, dribbling, and the need to urinate often during the night. One of the best ways to prevent the development of prostatitis, which affects about half of all men during their lifetime, is to keep the immune system in optimal condition. Providing the gut—which controls 70 to 80 percent of immune function–with probiotics on a regular basis in the form of a supplement can help men meet that goal.
Among the common causes of bacterial prostatitis are urinary tract infections, epididymitis, and urethritis. The bacteria that cause these infections and result in prostatitis may be held at bay or eliminated if the gut is well populated with probiotics. Therefore, regular ingestion of probiotics can assist in preventing the development of acute and chronic prostatitis by fighting both inflammation and the possibility of infection.
Although prevention is a goal, prostatitis can still develop, and that’s when probiotics can help with management. Both acute and chronic bacterial prostatitis are caused by bacteria and are treated with antibiotics, which places men at risk of developing antibiotic-associated diarrhea. In the case of chronic bacterial prostatitis, the infection frequently returns and needs to be treated for months, placing men at additional risk.
Therefore if you do develop a case of bacterial prostatitis, taking a greater dose of a combination of beneficial bacteria could work to prevent or reduce inflammation as well as antibiotic-associated diarrhea if your doctor has prescribed these drugs to treat your condition.
Some experts believe that an imbalance in the bacteria normally found in the urethra may reach the prostate and be involved in causing chronic prostatitis. They also suggest that the common use of antibiotics (typically prescribed for chronic prostatitis) may trigger the disease. (Liu) If this is the case, then use of probiotics could be helpful in managing prostatitis.
Another theory about prostatitis is that it is an autoimmune disorder. Since probiotics are immune system supporters, regular use of beneficial bacteria could serve to boost the immune response and guard against this inflammatory disease.
The most common type of prostatitis is a nonbacterial form known as chronic prostatitis/chronic pelvic pain syndrome. However, even though this prostate disease is termed “nonbacterial,” disease-causing microorganisms can still play a role. In fact, two potential causes of nonbacterial prostatitis are atypical bacteria that resist treatment with antibiotics and having a history of bacterial infection in the prostate. Therefore, use of probiotics on a daily basis or at least when a prostate problem is suspected or has developed is a wise move.
Benign Prostatic Hyperplasia
An enlarged prostate, or benign prostatic hyperplasia (BPH), affects about one-third of men by the time they reach age 50 and 70 percent of males by age 70. The condition is not caused by bacteria, but that does not mean probiotics cannot be helpful in managing this common disease. In fact, one of the most important things you can do to help prevent BPH is to keep your immune system functioning optimally by taking high-quality probiotics on a regular basis. A well-balanced bacterial environment in the gut helps ward off inflammation and supports a healthy prostate gland.
For example, daily use of a combination of probiotics can boost immune system function, which can help the body fight BPH symptoms. Urinary tract infections frequently occur along with BPH, and a steady course of probiotics can assist in preventing and managing such infections.
If BPH should develop, probiotics can be part of a proactive management plan. Restoring the bacterial balance in the gut will enhance immune system function and help fight inflammation.
Although the exact causes of prostate cancer are not known, there are several theories, including a role for genetics and various environmental causes. One theory is that inflammation plays a part, and if this is true then probiotics can be helpful in prostate cancer prevention. Inflammation can damage DNA, which in turn can cause cells to turn cancerous. In addition, probiotics support healthy immune function, which is a safeguard against development of cancer.
For prostate health, L. acidophilus has been used to determine its effect on the percentage of volume change of the rectum (PVCR) in men with prostate cancer who are managed with radiation therapy. PVCR is an important factor in men who receive this type of prostate cancer treatment because it has an effect on prostate movement and position and thus the accuracy and the effectiveness of the radiation treatment.
In the study, 40 men receiving radiation treatment were given a capsule containing either L. acidophilus or placebo twice daily. Men who took the probiotic has significantly lower median rectal volume and PVCR values than did men in the placebo group. Therefore, L. acidophilus helped reduce PVCR, which the authors noted “is the most important determining factor of prostate position during radiation therapy for prostate cancer.” (Ki)