Consuming probiotic bacteria could have a beneficial effect on your respiratory tract and viral illnesses. There is a strong connection between gut flora and protection of the respiratory tract from viruses. Probiotics are live microorganisms that, when administered in adequate amounts, deliver health benefits on the host.
This connection exists because both the intestinal and respiratory mucosa have similar characteristics and structures.
The mucosa is the primary site where most common viruses, including those that cause the common cold, flu, and the coronavirus, gain entry into the body.
Ideally, the mucosa of the digestive and respiratory tracts is protected from infection by a number of reinforcements. Collectively known as the mucosal defense system, these help to keep potentially harmful viruses and bacteria at bay while allowing healthy probiotics to thrive.
Unfortunately, these defense systems are not always in top form and cannot prevent all infectious illnesses. Advancing age, stress, and chronic diseases can weaken immune defenses. But, research has shown that probiotics stimulate and boost mucosal defenses, both for the gastrointestinal and respiratory systems. While many of the probiotic organisms consumed may end up in the gut, some do colonize parts of the respiratory tract. The mucosal defense systems get activated by these healthy organisms.
Healthy bacteria in probiotic foods and supplements help amplify general systemic immune functions as well, keeping the body ready to fight off infections.
These two effects of probiotics – shielding the mucosa and boosting immune function – work together to both decrease the incidence of viral infections and to reduce the severity if you do get sick. Several small studies have found that probiotics have beneficial effects against respiratory tract infections. A recent review concluded that probiotics have a positive influence on several outcome measures.
- Reduce the total number of respiratory tract infections
- Reduce the average length of illness
- Reduce the use of antibiotics
- Reduce school and work absences
One study evaluated a blend of probiotics that included B. lactic, L. planetarium, and L. rhamnosus. The study randomized 250 healthy adults to receive this probiotic blend or a placebo daily for 90 days during the flu season.
The impact this probiotic treatment had on respiratory infections was huge! The number of flu and flu-like viral illnesses were reduced by 75%! The rate of colds (also a viral illness) was reduced by 39%.
In the small number of subjects on the probiotic supplement who did get sick, probiotic still had a beneficial impact, reducing both the severity and duration of viral illness. Symptom severity in flu was reduced by 37%.
The length of illness was also reduced, by about one day on average for colds, three days for coughs, and close to one-and-a-half days for all acute upper respiratory tract infections overall.
With this growing evidence that probiotics reduce the risk and duration of respiratory tract infections, as well as reducing antibiotic use and absences from work, researchers examined the potential clinical and economic impacts in Canada.
Sponsored by The Alliance for Education on Probiotics, one study included researchers from Western, Lawson Health Research Institute, Laval University and Utrecht University. It incorporated two separate scenarios from two meta-analyses. (A meta-analysis combines data from multiple studies using a statistical approach.)
Results from the study showed regular probiotic use could eliminate as many as 2.3 million days per year of respiratory tract infections – resulting in 330,000 to 500,000 fewer sick days for Canadians and 52,000 to 84,000 fewer antibiotic prescriptions.
This would translate to $1.3 to $8.9 million in health-system savings. When accounting for productivity losses due to illness, it could save $61.2 to $99.7 million.
Respiratory tract infections are usually highly contagious infections of the sinus, throat or airways, including influenza. About 5 to 20 per cent of the Canadian population experience at least one respiratory tract infection per year, and 3 per cent of all health-care costs stem from these illnesses.
“If we could reduce the burden of respiratory tract infections, it would benefit both patients and Canadian taxpayers,” said Gregor Reid, Director for the Canadian Centre for Human Microbiome and Probiotic Research at Lawson and professor at Western’s Schulich School of Medicine & Dentistry.
Those who stand to benefit most include children under the age of 10, people living in a community setting (including office work in open spaces) and those not vaccinated against influenza.
Although respiratory tract infections are typically viral, about one-quarter of patients are also prescribed antibiotics (which offer benefits only against bacterial infections). “Antibiotics can have serious side effects like destroying many beneficial bacteria in the human body,” said Reid. Widespread antibiotic use has created “superbugs” that are largely resistant to current antibiotics.
This is why the use of probiotics is an important defense against respiratory tract infections.
“People are increasingly making probiotics a part of their daily diet or dietary supplements for their proven health benefits,” explained Reid. “The fact probiotics can also be used to prevent respiratory tract infections makes them even more important.”
Foods with probiotics:
- Kombucha is a fizzy fermented black or green tea made with a SCOBY, a “symbiotic culture of bacteria and yeast.” Drink only unpasturized kombucha, however, as pasteurization kills gut-healthy probiotics.
- Sauerkraut is a great source of live active cultures. However, many types of sauerkraut available today are pasteurized or prepared with vinegar instead of the lactic acid that gives the tart food its gut-friendly effects. Fiber, vitamins C, B, and K, iron, and manganese add to the health benefits, but be sure to check the label and buy fermented, unpasteurized sauerkraut.
- Dark Chocolate contains important anti-inflammatory antioxidants and provides gut-healthy probiotics. Dark chocolate with 70% or more cacao also delivers prebiotics, a food source for the microbes in your gut.
- Kimchi is a traditional spicy Korean side dish made from vegetables and the lactic acid bacteria Lactobacillus kimchii, as well as some other lactic acid bacteria that boost gut health. Just like sauerkraut, kimchi may come fermented with healthy probiotics, or it may be pasteurized. Choose unpasteurized kimchi for the live cultures.
- Natto is made from soybeans and is fermented with Bacillus subtilis bacteria. The enzyme nattokinase may help treat cancer, endometriosis, fibromyalgia, and infertility. The probiotic benefits ease gastrointestinal conditions and allergy symptoms and can boost immune function.
- Tempeh is a fermented soybean food is that is usually found as a loaf or patty. Many people eating plant-based diets use it as an alternative to poultry and meat. A great source of probiotics, protein, and calcium, tempeh also contains many other essential vitamins and minerals.
- Cucumbers that have been left to ferment in their own lactic acid bacteria along with water and salt become sour and create probiotic-rich pickles; they are a great source of probiotics. These pickles are not stored on a shelf in the supermarket like pickles made with vinegar, but rather, are found in the refrigerated section. They’re low in calories, high in vitamin K, and make for a satisfyingly crunchy snack.
- Olives have two strains of bacteria – Lactobacillus plantarum and Lactobacillus pentosus – and are naturally ferment in salt-water-brined. These bacteria reduce bloating and other symptoms of IBS, helping to flatten the stomach. Look for organic green olives for the probiotic benefits.
- Beet Kvass is a traditional Russian fermented drink. Like kombucha, because of its fermentation process and probiotic content, kvass has a similar taste to beer, and develops higher alcohol content the longer it ferments. While traditionally kvass is made from rye bread, it can also be made from other foods such as beets and comes in a variety of flavors.
- Miso is a paste made from soybeans — and sometimes mixed with barley, rice, or rye as well — that is fermented with a starter called koji. It is added to many dishes and is common in miso soup. Research shows that miso can lower heart rate and fight cancer. It provides many essential nutrients, including B-complex vitamins, vitamin K, copper, and manganese.
Capers are the immature flower buds of a thorny bush with white or pink flowers with purple stamens. The capers are harvested before they can even appear or bloom. The plant is cultivated in Italy, Morocco, and Spain, as well as Asia and Australia. To turn the unripened bud into the salty green pea-sized ball, it is dried in the sun and then pickled in vinegar, brine, wine, or salt. The curing brings out a tangy lemon-like flavor, which is similar to green olives.
If the flowers are allowed to mature and be pollinated, they develop into caperberries. These fruits usually grow to the size of olives and are filled with multiple small seeds, which grow bigger as the berry matures. Just like capers, caperberries are prepared by brining or curing.
The Capparis spinosa plant has also been used throughout history for pharmacological purposes. In ancient Egypt, the root of the caper plant was used to help manage liver and kidney diseases, while ancient Romans used it to help alleviate paralysis. Other illnesses that the Capparis spinosa plant was used for include toothache, fever, headache, painful menstruation, rheumatism and sciatica.
While capers are small, they’re packed with essential vitamins and minerals. Capers are rich in calcium, magnesium, potassium, folate and vitamins A and K. It also has vitamin C, niacin, iron, phosphorus and zinc in trace amounts. They also have alkaloids, flavonoids, terpenoids and tocopherols, which play an important role in regulating cellular enzyme function, inflammatory responses and other important body functions.
Other benefits include:
- Diuretic and antihypertensive – A 2007 animal study published in the American Journal of Pharmacology and Toxicology showed that Capparis spinosa extract helped increase urinary sodium and potassium excretion, leading to lowered blood pressure levels.
- Anti-inflammatory – Two studies from BioMed Central show that capers contain compounds that may help suppress interleukin-17 and promote interleukin-4 expression, which are important factors in easing or stopping inflammation from occurring. They also exhibit chondroprotective (joint spacing) properties that might rival nonsteroidal anti-inflammatory drugs (NSAID) typically prescribed for pain and swelling.
- Antidiabetic – In a 2017 animal study from the Avicenna Journal of Phytomedicine, researchers found that the aqueous extract of the Capparis spinosa plant contains antihyperglycemic properties, which may regulate glucose production and restore insulin sensitivity.
How to Buy
Capers are available at most markets. They can also be found in a variety of specialty and health food shops. When selecting them, look closely at the packaging to determine their origin and preparation method.
There are several varieties of capers, classified by size and region of origin. The smallest are grown in France and known as “nonpareils.” Spanning less than 1/4 inch, these capers tend to be the most flavorful and the most expensive.
Larger capers, known as “surfines” are among the most common varieties. Sizable capers such as capotes, capucines, fines, and grusas are less common.
Capers are typically packaged in small jars, no more than four ounces, in a vinegar brine. You can find them in the pickled food aisle alongside olives. Smaller nonpareil capers are more expensive than larger capers.
How to Store
Capers may be packed in brine or salt and this will determine how they should be stored; both should be in an airtight container. Brine-packed capers should be completely submerged and will keep for nine months or longer in the refrigerator. Unopened jars can be stored in the pantry. Salt-packed capers can be stored at room temperature for up to six months.
Foul odors and dark coloration in the jar are signs that the capers have gone bad and need to be discarded.
How to Cook
Due to their strong taste, it’s best to use caper sparingly.
Capers are ready to use out of the jar. Many recipes call for rinsing the capers to remove some of the salt or vinegar, which allows the true flavor of the caper to come through. Blot the caper dry with a paper towel after rinsing. Larger capers should be chopped before use. Some recipes, such as sauces, may call for finely chopped capers while others use them in a puree like tapenade. Most of the time, you’ll simply add them to the hot pan with other ingredients, typically toward the end of the cooking process. This allows the capers to keep their shape and maintain their signature taste.
Vegan Pasta Puttanesca With Capers and Olives
Jolinda Hackett/ Photo credit: DFreshPhotography / Twenty20
- 1 tablespoon olive oil
- 3 cloves garlic (minced)
- 1 tablespoon fresh basil (chopped)
- 2 tablespoons capers
- 1/4 cup sliced kalamata olives
- 1/2 teaspoon red pepper flakes (or to taste)
- Dash salt (or to taste)
- Dash pepper (or to taste)
- 1 tablespoon olive brine
- 1 (14-ounce) can crushed tomatoes
- 1/2 pound dried gluten free pasta (of your choice)
- Sauté the garlic in olive oil for a minute.
- Add the basil, capers, olives, and red pepper flakes, and cook for another two minutes.
- Reduce heat to low, and add the brine and tomatoes.
- Cover and simmer for at least 15 minutes.
- Serve hot over cooked pasta.
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