A lot of bacteria reside in our body. In fact, there are as many as 1,000 different types of them living in our body. They outnumber our cells by 10 to 1. Probiotics are simply good bacteria that can provide a lot of benefits to you, such as better digestive system, better mood, healthier skin, and weight loss. Some studies have also shown that gut flora can ma manufacture K and B vitamins. Those healthy living organisms can be obtained from foods and supplements. Some foods, like sauerkraut, kimchi, are rich in probiotics. Some supplements, like Metaflora, contain broad-spectrum probiotics with adequate amount to maximize the number of those bacteria in your gut. We can also take prebiotic fiber, which is food to probiotics, to tilt the bacterial balance further to the healthier side. So eating more fruits and vegetables like bananas and garlic can help.
The bottom line is that probiotics are important for our overall wellbeing. Daily exercise and staying abstemious from smoking can also help.
Resources
Gunnars (2018). https://www.healthline.com/nutrition/probiotics-101#gut-microbiome