Saccharomyces boulardii is a yeast (fungus) of natural origin, first isolated in the early 20th century from the bark of lychee and mangosteen by the French microbiologist Henri Boulard. Since its discovery, it has been used worldwide as a probiotic yeast that contributes to the well-being of the intestinal flora.
Saccharomyces boulardii as a probiotic yeast
Saccharomyces boulardii is not naturally present in the human gut microbiota; however, when taken orally, it is able to survive, multiply, and reach high concentrations in the intestinal tract, where it remains for several days before gradually disappearing once supplementation is discontinued.
At this level, Saccharomyces boulardii exerts a direct antibacterial activity: thanks to its so-called “magnet effect,” it binds and traps pathogenic bacteria on its surface, preventing their adhesion to and growth on the intestinal mucosa. In addition, its ability to release substances with antibacterial effects—such as mannose, glycoproteins, and enzymes like phosphatases or proteases—further enhances its effectiveness. Over the years, the anti-inflammatory and immunomodulatory properties of this valuable intestinal probiotic have also been studied, confirming its benefits of use.
Summer and travel: probiotics for an intestinal microbiota under stress
During the summer, rising temperatures and changes in daily habits—as well as travel to exotic destinations with dietary patterns and hygiene standards different from those we are accustomed to—can put significant strain on the balance of our intestinal microbiota.
The intestinal microbiota is the complex community of microorganisms that normally inhabit the gastrointestinal tract and play a fundamental role in the proper functioning of the immune system, which is largely based in the gut. In such situations, to counteract the proliferation of harmful bacteria and to prevent possible intestinal infections and so-called traveler’s diarrhea, supplementation with Saccharomyces boulardii can help us set off on vacation without fear of unpleasant side effects.
This valuable probiotic yeast has many beneficial properties. In addition to being able to survive perfectly in the acidic environment of the stomach and reach the intestine intact, it is also resistant to antibiotics, which eliminate not only harmful bacteria but also beneficial microorganisms. Moreover, its optimal survival temperature of 37 °C allows it to thrive in the human body, unlike its variant Saccharomyces cerevisiae, which is instead used in beer production.
Saccharomyces boulardii is effective because it is extremely rich in viable fungal cells, helps restore the balance of the intestinal microbiota, and may also be useful for individuals suffering from irritable bowel syndrome, as well as for preventing traveler’s diarrhea—functions that make it an ideal probiotic for travel.
Saccharomyces boulardii is effective because it is extremely rich in viable fungal cells, helps restore the balance of the intestinal microbiota, and may also be useful for individuals suffering from irritable bowel syndrome, as well as for preventing traveler’s diarrhea—functions that make it an ideal probiotic for travel.
Dosage, formulations, and contraindications of Saccharomyces boulardii
Saccharomyces boulardii, marketed as a dietary supplement—sometimes in formulations enriched with prebiotics, lactic ferments, and/or vitamins beneficial to gastrointestinal health—is generally safe. However, it is essential to consider contraindications and precautions before use.
Special attention is required prior to taking supplements containing Saccharomyces boulardii because, as it is a fungus, it is not recommended in cases of allergy or hypersensitivity to yeasts. In critically ill or immunocompromised patients, it may cause fungemia.
Vacation lifesavers: what to pack besides Saccharomyces boulardii
When traveling, health risks extend beyond intestinal dysbiosis and may spoil a holiday. What else should you remember to pack, along with your trusted travel probiotics?
Natural mosquito repellent spray for the whole family
To enjoy warm summer evenings outdoors without the “ouch!” and to protect even the youngest family members, don’t forget to bring a mosquito repellent spray. Formulated with natural essential oils, it releases substances that are unpleasant to insects but harmless to other animals, including humans.
If you are looking for a natural mosquito repellent, choose one based on Ledum palustre and essential oils of citronella, geranium, cypress, rosemary, and basil—long-lasting insect repellents effective even against the tiger mosquito.
These formulations are suitable for sensitive skin, including children’s skin, and can be sprayed on surfaces, animals, indoor areas, and outdoor spaces.
For jet lag and summer insomnia: rely on melatonin
If summer brings sleep disturbances—due to heat, changes in routine, or season—or if you are planning long-haul flights with a risk of jet lag, melatonin is a “must-have” not to forget at home. Combined with some of the most studied plant extracts known to support restful sleep—such as eschscholzia, oats, jujube, St. John’s wort, linden, hops, and uncaria—melatonin helps regulate the sleep–wake cycle and reduces the time needed to fall asleep, making it an effective remedy for insomnia.
Magnesium: the summer supplement against cramps and fatigue
Finally, if you’re planning active holidays in particularly hot destinations, magnesium in convenient ready-to-use pouches can help prevent fatigue and muscle soreness. Magnesium is effective in preventing cramps, which may occur due to intense physical activity and excessive sweating—factors that can quickly deplete the body’s mineral reserves, even though summer diets are typically rich in fresh fruits and vegetables.
