A healthy gut leads to a happy brain
The modern Western diet, in contrast to the food of our early ancestors, mainly comprises grains, dairy products, and processed meats. While the produce is exposed to pesticides and chemical fertilizers, animals are fed growth hormones, antibiotics, and even poisons such as arsenic to fatten and preserve them. And in the end, all these chemicals are consumed by humans. This is both unfortunate and unacceptable.
Do you know what the number one nemesis of your gut is? Two things actually occupy this position: antibiotics and commercially raised meats. The human body hosts a thriving ecosystem of nearly 100 trillion bacteria, more than 95 percent of which are located in your gut. These bacteria, along with viruses, fungi, and other microbes, together make up your gut microbiome. Therefore, we can say both antibiotics and processed meats are nothing short of kryptonite for your gut health.
Sadly, what’s bad for your gut is also bad for your brain.
Have you ever had a “gut feeling," an intuition based on something other than logic and reason, perhaps based on emotion? This is actually very common (and the reason behind the idiomatic expression); many people report that they literally feel something in their gut. Let’s decode this. Your gut and brain are in constant conversation, and the line they talk over is the vagus nerve – a direct highway running from your gut straight up to your brainstem. This gut-brain axis, as researchers call it, is why you feel “butterflies in your stomach” when nervous, and why irritation in the gastrointestinal system can trigger mood changes.
It also helps explain one of the more surprising facts in all of neuroscience: roughly 90 percent of your body's serotonin, the neurotransmitter most closely tied to feelings of well-being, is produced not in your brain but in your gut. Now you know why "trust your gut" makes so much sense.
Your gut flora help digest food, defend against pathogens, and produce beneficial short-chain fatty acids – compounds like butyrate, made when your gut bacteria ferment the fiber you eat. These fatty acids can directly alter the function of the blood-brain barrier, influencing how many nutrients and foreign substances can pass through it. In other words, the fiber on your plate today quite literally shapes what your brain is exposed to tomorrow.
To keep your gut healthy, eat organic produce whenever possible, but especially when it comes to the 12 most pesticide-laden fruits and vegetables – also known as the "Dirty Dozen." These are apples, celery, tomatoes, cucumbers, grapes, nectarines, peaches, potatoes, spinach, strawberries, blueberries, and bell peppers. On the flip side, the "Clean Fifteen" – produce like avocados, sweet corn, and pineapple – tend to carry far less pesticide residue even when conventionally grown, so you don't have to go organic on everything to make real progress.
With regard to meat, dairy, and eggs, drastically reducing your intake and only consuming organic, free-range varieties is a wise move. Fiber-rich foods support digestive health and regularity, which flushes away waste products, bad bacteria, and toxins – and, as we now know, feeds the very bacteria that produce the fatty acids your brain depends on. Incorporating broccoli, berries, legumes, and leafy greens in your diet will do the trick.
Prebiotics – carbs that nourish your body's good microbes – are found in onions, asparagus, and artichokes. Probiotic foods contain live bacteria that replenish your gut microbiome; they're abundant in fermented and cultured foods like sauerkraut, kimchi, kefir, and yogurt. New research shows that changes in your gut microbiome can influence the risk of brain disorders such as anxiety and depression – and probiotics could be a potent solution.
In one study, a group of women ate a cup of probiotic yogurt twice a day for a month, while a control group didn't eat any. They were then shown upsetting pictures while their brains' emotional responses were monitored with an fMRI. Can you guess who remained calmer and more stable? The yogurt group showed measurably reduced activity in the amygdala, the brain's alarm center for fear and threat – tangible proof that what you eat for breakfast can quiet down the very part of your brain responsible for anxiety.
