Mention the word ‘bacteria’ in a conversation and you’ll get mixed reactions: some will go ‘NASTY bugs that cause disease and spoil foods!’ while others may equate bacteria to the friendly fellows that keep our gut healthy and are added to (ridiculously high-sugar) yogurt!
The truth is the bacterial kingdom is a huge one – there are numerous pathogens that can cause a wide array of health issues but there are also lots of good bacteria such as Lactobacillus acidophilus or the bifidobacterium that have been linked to various health benefits. As you’ll discover in this article, these bacteria do much more than simply keep things running smoothly in our digestive tract.
And if you’re among those who think that the health benefits of probiotics have been overrated, keep scrolling to find out what happens if the delicate gut ecology is disrupted. I guarantee you’ll be surprised.
The amazing gut ecology
Did you know about 100,000,000,000,000 (100 trillion) microorganisms think of your gut as ‘home sweet home’? Yep, that’s a crazy lot of zeros! Just to give you a visual idea, if you laid one dollar bills end-to-end from the earth to the sun and back, you would require way more than one trillion bills! Now, do that a 100 times more to get a (vague) idea of how much 100 trillion is… Sounds like we’re more bacteria than human!
In fact, our gastrointestinal system is home to more than 400 different species of bacteria – colonization begins right after birth and is more effective if the baby is born via the vaginal route. These bacteria which prevent pathogens from multiplying in the gut, make up more than 75% of our immune system.
Health benefits of probiotics you’re probably unaware of.
Sounds farfetched or Sci-Fi like? Well, more and more studies are showing that our brains and gut are linked. Research suggests that when the gut is inflamed – this can occur if your diet is packed with processed ‘foods’ such as vegetable seed oils, sugar, refined carbs, gluten, soy and so on – it promotes the release of inflammatory cytokines in the blood. Basically, what these compounds do is tell the immune system, ‘Code Red, Code Red! There’s something going wrong – we need to be on the alert!’ This alert signal stresses you out. Plus these inflammatory cytokines are able to cross the blood-brain barrier where they induce inflammation in the brain, creating symptoms of depression.
In one study, 45 healthy participants were given either a placebo or a prebiotic before completing computer tests that assessed how they processed negative or positive words (emotional information). The researchers found that, compared to the control group, subjects given the probiotics paid more attention to the positive information than to the negative information. Similar effects have been noted amongst patients taking anti-depression or anti-anxiety drugs.
And a 2011 French study revealed that individuals who took probiotics for 30 days experienced decreased levels of psychological distress compared to the placebo group.
Behind the link
Probiotics exert their anti-depressant functions in two ways:
- By preventing or toning down gut inflammation, probiotics can thwart this inflammatory process and thus minimize and even stop brain inflammation.
- Probiotics have been found to calm depression by acting on the vagus nerve, a cranial nerve that conveys sensory information from the gut to the brain.
- Prebiotics appear to lower morning cortisol levels – high levels of this hormone have been linked to stress, anxiety and depression.
Did you know that weight gain has been linked to the composition of the gut flora? And that, compared to their leaner counterparts, obese individuals have a less diverse gut flora? In fact, it appears that obese individuals have 90% less bacteroidetes and 20% more firmicutes than lean individuals. So what, you may wonder? Well, firmicutes are better than bacteroidetes at extracting calories from food and storing them as fat. In other words, the more firmicutes you have in your gut, the more of your food will be converted into fat.
Moreover, as mentioned earlier, an unhealthy gut can lead to brain inflammation – inflammatory cytokines have been found to block leptin receptor sites, gradually making the body “leptin resistant”. Since the hormone leptin induces satiety and tells the brain to burn body fat for energy, leptin resistance makes it harder to lose weight by making you hungrier and making it harder for your body to burn fat.
Japanese researchers gave a group of 210 overweight women 7 ounces of fermented milk per day for 12 weeks. Some of the women received milk containing Lactobacillus gasseri SBT2055. The researchers found that, compared to the control group, those who received the ‘spiked’ drink lost 8 to 9% of their visceral fat. This type of fat surrounds the organs and can cause numerous health issues when present in excess. These women also lost 1 to 3% of their belly fat.
In another study, obese individuals were given either a placebo or a probiotic containing Lactobacillus rhamnosusfor 12 weeks. This constituted the weight loss plan which was followed by a 12-week weight maintenance plan. The researchers reported that the women in the treatment group lost an average of 9.7 pounds, compared to 5.7 pounds in the placebo group. No significant weight loss changes were seen between the men in the placebo and treatment group. What’s interesting is that the women who received the probiotic continued to lose body fat after the maintenance phase whereas the control group gained weight.
In a lab study, scientists transferred the gut flora of obese mice into the guts of skinny ones. Guess what happened? These skinny mice immediately started eating excessively and gradually became obese.
Behind the link
- Probiotics may help improve metabolism while increasing adiponectin, an anti-inflammatory signal that enhances the body’s ability to burn belly fat. Adiponectin also regulates lipid and glucose metabolism.
- Probiotics can help decrease intestinal permeability thus keeping the intestinal barrier strong. In doing so, the friendly bugs could help prevent inflammatory compounds from entering the bloodstream and reaching the brain where, as explained earlier, they can induce leptin resistance.
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