Bacteria can also perform this service outside the gut. Yogurt is nothing other than milk that has been predigested by bacteria. Much of the sugar in the milk (lactose) has already been broken down and transformed into lactic acid (lactate) and smaller sugar molecules. That is why yogurt is both sweeter and sourer than milk.

The newly formed acid has another effect on the milk. It causes the milk protein to curdle, giving the yogurt its characteristic thickness. Predigested milk (yogurt) saves our body some work-we just have to finish off what the bacteria started.

Bacteria do more than just break down our food. They also produce completely new substances. Fresh cabbage, for example, is less rich in vitamins than the sauerkraut it can be turned into-those extra vitamins are made by bacteria.

Too much cholesterol is bad, but too little is harmful too.

We swallow billions of bacteria each day, without thinking about it. A small proportion even survive the acid bath of the stomach. No one knows the majority of these bacteria. They presumably do not harm us, and some even benefit us. A few are pathogens, but they cannot harm us because of their small number. The fraction of these bacteria that are checked out by scientists, and given the official seal of approval, are known as probiotics.

We have heard that yogurt is probiotic, and it sounds good, but what does it mean?

Helpful bacteria is important for life. If a baby is raised in a bacteria-free habitat, they will not develop a strong enough immunity to survive. Our ancestors had no idea that bacteria existed, but they intuitively did the right thing. They protected their food from the bacteria that made it rot, by handing it over to the care of good bacteria. They used bacteria to preserve their good.

Each culture has its own dishes to do this. Germany (sauerkraut, pickled gherkins, sourdough pretzels), France (crème fraîche), Switzerland (hole-riddled cheese), Italy (Salami, preserved olives), Turkey (Ayran, a salty yogurt drink). These foods would not have existed without microbes. In Asia, there is soy sauce, kombucha, miso soup, kimchi, lassi. In Africa, there is fufu. The list is endless. These foods that rely on bacteria undergo fermentation, a process that usually results in acid production which makes yogurt or vegetables taste sour. This acid, along with good bacteria, protects the food from dangerous microbes. Fermentation is the oldest and healthiest way of preserving food.

Yogurt and other fermented products came about by accident. Someone forgot the milk outside, bacteria found their way in, the milk thickened, and a new kind of food had been invented. Today’s yogurt products have less diverse bacteria than traditional types.

To summarize: any yogurt can be good for you, although not everyone can tolerate milk protein or too much animal fat. The good news is that there is a world of probiotics beyond yogurt. Researchers are busy in their laboratories examining selected bacteria. They dribble bacteria directly onto gut cells in petri dishes, feed mice with microbial cocktails, or get volunteers to swallow capsules full of living microorganisms. Probiotic research has roughly defined three areas in which our good bacteria can display fascinating abilities.

Gut: The Inside Story of Our Body’s Most Underrated Organ

1. Massaging and Pampering: Many probiotic bacteria possess genes that enable them to produce small fatty acids like butyrate. This soothes and pampers the villi in the gut. Pampered villi are much more stable and likely to grow bigger than unpampered ones.

2. Security Service: Good bacteria protect the gut by occupying the places pathogens like to infect us the most.

3. Good Advice and Training: Bacteria provides us with insider information and useful advice. What do the different bacteria’s outer walls look like? How much protective mucus is needed? What quantity of bacterial defense substances (defensins) should the gut cells produce? Does the immune system need to be more active in its reaction to foreign substances or should it sit back and accept newcomers?

Probiotics are good for treating diarrhea.

Gastroenteritis (stomach flu) and diarrhea caused by taking antibiotics can be helped using various pharmacy-bought bacteria. They can reduce the length of such a bout of diarrhea by about a day. At the same time, unlike most diarrhea medications, they are almost free of side effects. That means they are particularly suitable for small children and old people. In conditions like ulcerative colitis and irritable bowel syndrome, probiotics can increase the intervals between diarrhea attacks or inflammatory flare-ups.

Good for the immune system.

For people who tend to get sick often, it can be a good idea to try different probiotics, especially when colds are rife. If that is too expensive, eating a pot of yogurt a day may be enough, since bacteria don’t necessary have to be alive to trigger some mild effects. Studies have shown that old people and high-performance athletes, in particular, are less prone to catching colds if they take probiotics regularly.

Gut: The Inside Story of Our Body’s Most Underrated Organ

The pharmaceutical industry and academic research has not advanced far enough to help prescribe a product for constipation or flatulence. Try out different products for yourself until you hit upon a bacterium that seems to help. Buy the product from the pharmacy, try it for about four weeks, and if you see no improvement, move on to the next bacterium.

There is one limitation to the efficacy of all current probiotics we take: they are isolated species of bacteria bred in the lab. As soon as we stop taking them, they mostly disappear from our gut. Every gut is different and contains regular teams that help each other or wage war on each other. When somebody new turns up, they are at the back of the line when it comes to allocating places. So, currently, probiotics work like hair conditioner for the gut. When you stop taking them, the regular flora folk have to continue their work. To achieve longer-lasting results, researchers are now looking at the possibilities of a mixed-team strategy: taking several bacteria together, so that they can help each other to gain a foothold in unknown territory. They clear away each other’s waste and produce food for their colleagues. Some products you can buy at the pharmacy, drugstore, or supermarket already use this strategy, with a mix of our trusty old lactic-acid friends. Gut: The Inside Story of Our Body’s Most Underrated Organ

From Gut: The Inside Story of Our Body’s Most Underrated Organ

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