You've likely heard about the benefits of healthy gut flora, but you may not know when to take probiotics or what to expect after taking them. How do you know which probiotic is best for you? What happens to your body when you start taking probiotics? What are the signs probiotics are working, and are there any signals that say you should stop taking them? Here’s what the science says.
The Benefits of Probiotics & How to Choose The Right One For You
Probiotic-rich foods and supplements introduce friendly bacteria into the gut, which helps maintain a healthy gut microbiome, lining, and barrier, while also aiding digestion. However, there are many strains of probiotics, and each one has a different effect.
You may need to experiment with products to find one that works for you. For example, a mood probiotic may not help constipation as much as one designed specifically for gut health. Start by reading the suggested uses on the label, and talk to your doctor about the best strain for your goals. In addition, it’s a good idea to read up on which probiotic strains have benefits backed by research studies.
Another important thing to keep in mind is how the product you choose should be stored. Probiotics are live cultures that must be alive when you take them to have a benefit. Some types of probiotics are sensitive to heat and moisture and should be stored in a cool, dry place for best quality. Other strains are shelf-stable, but often only until you open the package, after which exposure to moisture causes them to degrade. For best results, follow storage instructions to maintain potency.
What Happens When You Take a Probiotic Every Day?
Daily consumption of probiotics has several health benefits. You might notice changes right away or over time. However, the benefits may depend on the quality of your product and the strain. Here are five things you may notice:
You May Have Less Constipation or Diarrhea
Numerous bacteria and fungi coat the lining of your intestinal tract and interact with your nervous, immune, endocrine, and metabolic systems. These microorganisms influence the natural movement or motility of your intestines and speed up or slow the passage of food and waste through your system.
Disruption in the balance of these microorganisms can cause digestive issues such as constipation or diarrhea. At the same time, constipation or diarrhea can influence the balance of bacteria in your gut, creating a two-way relationship.
A probiotic may help to build healthy gut flora and lead to less constipation or diarrhea. A 2018 study found that probiotics improved symptoms of diarrhea-dominant irritable bowel syndrome (IBS) in adults. After eight weeks of supplementation with Lactobacillus gasseri BNR17 probiotics, patients had less pain and bloating and decreased diarrhea frequency.
Other research shows probiotic supplementation with L. plantarum IS 10506 increases the populations of gut microorganisms, causing bacteria to release more short-chain fatty acids (SCFA) and may help to increase transit time in the gut.
Another study found that long-term supplementation with L. reuteri DSM17938 lowered levels of serotonin, which increased intestinal movement. The study results suggest that probiotics help with constipation by influencing neurotransmitter levels within the gut.
Your Immune System May Get Stronger
Your gut plays a central role in your immune health. Cells in the lining of your intestines stimulate immune cells and the release of antibodies in response to the bacteria in your gut.
Certain cells in the lining also fit together to form a barrier between your intestines and your bloodstream. Bacteria stick to this lining and stimulate the release of a mucus film that helps maintain barrier health.
An imbalance in bacteria or the growth of harmful bacteria in the gut leads to a weak barrier, enabling toxins, proteins, and other substances to leak into the blood. This leakage triggers an inflammatory response, stimulating a potential cascade of health issues.
However, friendly probiotic bacteria compete with bad bacteria for nutrients, preventing them from sticking to the barrier. A daily probiotic product or a diet rich in probiotic or fermented foods may help build a healthy balance of bacteria and encourage overall digestive health.
According to a review article, L. rhamnosus HN001 and B. lactis HN019 strains also increase white blood cell activity by stimulating chemicals called interleukins.
Your Mood May Improve
The microbiome releases neurotransmitters, dopamine and serotonin precursors, short-chain fatty acids, and other chemicals as part of normal digestion. While the exact mechanisms are unclear, scientists believe that some of these chemicals may interact with the brain via your vagus nerve or the bloodstream, influencing brain activity, mood, and behavior.
While neurotransmitters inside your gut don’t reach your brain, their precursors can. Amino acids such as tryptophan, tyrosine, and phenylalanine can be transported across the blood-brain barrier, where they are used to biosynthesize serotonin and dopamine - neurotransmitters responsible for mood and cognitive function.
Researchers have completed several studies on probiotics for anxiety and depression. While some show no effect compared to a placebo, other studies show that certain probiotics can influence anxiety and depression scores. While more research is necessary, for some people, certain probiotic strains may improve mood and mental health.
Your Vaginal Infections May Improve
There are some specific benefits of probiotics for women, too. For example, a daily probiotic may help improve chronic UTIs and vaginal infections. Experts believe that one reason vaginal infections happen is because bacteria from the stool migrate to the vagina. If harmful bacteria can do this, it makes sense that beneficial bacteria can, too.
One study found that people who took L. rhamnosus GR-1 and L. fermentum RC-14 for 60 days improved asymptomatic bacterial vaginosis (BV). The probiotics helped vaginal flora to return to normal without any reported side effects.
Research also shows that taking probiotic capsules by mouth may help chronic or recurring UTIs. Scientists believe these bacteria may stick to the lining of the urinary tract and prevent harmful organisms from growing. In particular, L. rhamnosus and L. fermentum may be effective for this purpose.
Frequent antibiotic use is common with chronic UTIs, often leading to antibiotic resistance. However, probiotics may help prevent resistance, too. A study in postmenopausal women with recurrent UTIs compared the effects of antimicrobial medication to daily probiotics over 12 months. The study found the probiotics didn't compare to the medication but did lead to lower antibiotic resistance.
Your Cholesterol Levels May Improve
Probiotics may lower cholesterol levels in a few ways. Some strains produce enzymes that help break down or deconjugate the bile acids that convert fat into cholesterol. This makes bile acids and fats harder to absorb, leading to higher excretion in your stool and lower cholesterol levels in the blood.
Probiotics also increase SCFA production and increase SCFA influx into the liver. Once inside the liver, SCFAs regulate liver proteins and block circulating lipoprotein lipase, leading to lower cholesterol levels in the blood.
Possible Side Effects of Probiotics
Probiotics are safe for most people, but side effects can happen, though they are often mild and temporary. In rare cases, some people may experience more severe side effects.
Temporary Gas & Bloating
One of the most common side effects of probiotics is temporary digestive upset. You may find that your probiotics initially cause gas, constipation, bloating, and abdominal pain. Nausea and cramps are also common. However, these symptoms are usually mild and improve in a few weeks.
Probiotic supplements can contain allergens such as eggs, soy, dairy, and yeast, which may cause allergic reactions. Additionally, many supplements contain lactose, which may cause digestive distress if you’re lactose intolerant.
Some strains, such as L. casei TISTR 389 and L. bulgaricus TISTR 895, may produce histamine. Histamine has many functions but is also responsible for allergic symptoms, diarrhea, vomiting, and abdominal pain.
Most people have enzymes that break down histamine, which stops it from causing symptoms. However, people with histamine intolerance may have reactions to histamine-producing probiotics.
It’s simple for scientists to determine if a specific probiotic strain is histamine-producing simply by looking at its genetic sequence. For example, L. plantarum PS128 does not have the genes necessary to produce histamine.
You may also notice increased thirst in the first few weeks of supplementation as your body gets used to the changes. With more thirst, you may drink more fluids, leading to increased urination. These side effects may be more common with Saccharomyces boulardii or other yeast-based products.
Higher Risk of Infection for Some
Since probiotics introduce bacteria into your body, it is possible to develop an infection from these bacteria. The risk is higher for people with a suppressed or compromised immune system, such as those with HIV and cancer, and for older adults and premature babies.
There are a few reported cases of endocarditis in patients with heart defects, blood and lung infections, and liver abscesses after using probiotics. However, these are rare. Still, it’s best to talk to your doctor first about probiotics and weigh the risks and benefits if you are an older adult, are hospitalized, or have a chronic illness.
Possible Neurological Symptoms from Psychobiotics
Some unique probiotic strains called psychobiotics have been shown to modulate neurotransmitter levels and/or activity in animal studies, and can affect mental health in humans.
If you have a mental health condition or are taking medication that affects neurotransmitters, you should consult with your health care provider before starting and while taking a neurologically active probiotic. For example, serotonin syndrome could be an adverse effect from taking a probiotic that raises your serotonin levels if they are already high.
How to Manage Probiotic Side Effects
Most people don’t have problems with probiotics, but everyone has a unique gut. If you encounter side effects, start by trying a different strain. The following tips offer ways to lower the chances of more intense side effects.
Start with a Low Dose
You can help your body adjust to probiotics by slowly adding supplements or fermented foods to your diet and routine. Start with a lower-than-average dose and work up to the full dosage over the course of a few weeks.
Know When to Stop
Side effects of probiotics are usually temporary and self-limiting. That said, there might be times you need to stop probiotic supplementation, including if:
- You develop allergy symptoms, such as watery eyes, itchy skin, or a runny nose
- Digestive side effects don’t get better within a few weeks
- You experience adverse changes to your mental health or sleep when taking a psychobiotic
- You don’t notice any changes in your health
When to Talk to Your Doctor
Most research shows that probiotics are safe. In most cases, you can likely take a probiotic without much worry. However, it’s best to talk to your doctor if you have a chronic illness or higher risk of infection, or before starting a neurologically active medical probiotic like Neuralli™.