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Scientists May Have Found Humanity's Sixth Sense—In Our Gut

Scientists May Have Found Humanity's Sixth Sense—In Our Gut

Yahoo28-07-2025
"Hearst Magazines and Yahoo may earn commission or revenue on some items through these links."
Here's what you'll learn when you read this story:
A new study says that the organisms in our gut have more direct influence on our actions that we previously thought.
Scientists analyzed an ancient protein called flagellin, released from the tail of bacteria (known as the flagella), and found that the gut's neuropods could sense this protein, triggering an appetite-suppressing response.
The research team hopes that a greater understanding of what impacts the microbiome could help experts develop treatments for obesity and psychiatric disorders.
Science textbooks typically describe humans as having five senses—seeing, smelling, hearing, seeing, and touching. While it's true these are the most outward and obvious senses, they're far from the only ones. For one, there's proprioception, which describes the body's ability to sense its position and movement in space—that may not seem like a big deal, but if you live without it, poor balance is only the beginning of your problems.
And now, a new study led by scientists at Duke University suggests that there's yet another sense lurking in our gut. This is the home of the microbiome—a collection of bacteria, fungi, viruses, and archaea that impact our immune system, our digestion, and even our mental health. And it's within this microbiome that bacterial flagella (the tail-like structure bacteria use to swim) release an ancient protein known as 'flagellin.' This new study, published yesterday in the journal Nature, describes the flagellin as the method through which neuropods, essentially neurons in your gut, regulate appetite.
According to the scientists, neuropods contain a receptor known as 'toll-like receptor 5,' or TLR5, which then sends impulses to the brain via the vagus nerve—the gut-brain information highway that is also the longest nerve of the body's autonomic nervous system. This shows how microbes living in our gut can communicate with the human brain.
'We were curious whether the body could sense microbial patterns in real time and not just as an immune or inflammatory response,' Diego Bohórquez, the senior author of the study from Duke University, said in a press statement, 'but as a neural response that guides behavior in real time.'
To test the idea, scientists fasted mice overnight, and when supplied with a dose of flagellin to the colon, the mice ate less than expected. When the same experiment was conducted with mice that lacked the TLR5 receptor, the mice ate their fill and quickly gained weight. This suggests that this microbe-to-brain communication pathway plays a role in giving humans—and other mammals—the 'I'm full' sense. This is what the researchers call our 'neurobiotic sense,' and it very well could be our sixth sense. Or, maybe seventh? Or eighth? We've lost count.
Of course, the microbiome is an immensely chaotic environment, containing some 100 trillion microbial cells that can all be influenced by diet, lifestyle, and environment. The next step for the scientists is to figure out what diets change the microbiome and in what ways.
'Looking ahead, I think this work will be especially helpful for the broader scientific community to explain how our behavior is influenced by microbes,' Bohórquez said in a press statement. 'That could be a key piece of the puzzle in conditions like obesity or psychiatric disorders.'
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time7 hours ago

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Dermatologists' Number-1 Tip for Longer, Stronger Nails

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time8 hours ago

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What Your Swollen Fingers Are Trying to Tell You About Your Health

"Hearst Magazines and Yahoo may earn commission or revenue on some items through these links." You know that how your body looks and feels sometimes changes by the day. One day you're so bloated that your jeans feel a size too small, while another you wake up and your skin looks dewy and glowing. Swelling, especially in places like your hands and feet, often seems to come and go just as frequently. As such, there's typically no need to rush to the doctor if you suddenly can't slide your wedding ring off your finger. But in some cases, swollen fingers may point to the presence of a more serious health condition. Here are the most common causes of swelling in your fingers, plus when you should be making an appointment with your healthcare provider. 1. 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time12 hours ago

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Want to Make Real Big Arm Gains? This Quick Fix Can Make a Huge Difference.

"Hearst Magazines and Yahoo may earn commission or revenue on some items through these links." EVEN IF YOU'RE not a bodybuilder with 20-plus-inch arms, we're willing to bet that biceps curls are somewhere in your weekly workout routine. After all, who doesn't want arms that stand out even when they're covered up? But there's a downside to such a dedicated focus on your pump. Countless curls performed every day in every gym across the globe are near-useless due to bad form. Technique can fall apart fast, which is likely why curls are among the most 'cheated' moves in strength training. You know what we're talking about: those sloppy sets that are more to stoke your ego than build up your body. Yes, there is a time and place for 'cheat reps,'—mostly, for advanced lifters—but if you can't complete all of your normal reps without throwing in some body English (e.g., arching your back, twisting your torso) or enlisting supporting muscles to generate momentum (rocking your hips to swing the weight), you're doing it wrong. And bad form isn't always that obvious or dramatic; perhaps you simply let your elbows travel forward as you fatigue during your final reps, or you let the tension out of your core. Whatever the movement dysfunction is, the results are the same: less effective sets and slower overall gains. That ends today. By paying more attention to each rep and really feeling what each muscle and joint is doing, you can firm up your form and fast-track your gains to build the big arms you want. Here's how. The Simple Secret Behind a Perfect Curl One of the things every great trainer understands is that in practice, there is no such thing as an 'isolation exercise.' The term is used to describe a move that involves a single joint, such as the biceps curl, which flexes the elbow. But even if it were true that a single muscle was involved in bending the elbow (it's not; your biceps, brachialis, and brachioradialis all chip in), that muscle still wouldn't truly be acting in isolation. Indeed, a whole armada of supporting muscles in your torso and core kick into gear to provide the necessary stability for the movement to happen. That's where the secret to performing the biceps curl perfectly begins: in the supporting musculature. You'll need to keep your abs, glutes, and mid-back muscles contracted (or 'braced') and your shoulder blades pulled back and down during each rep. That's what will keep you from losing your balance and needing to shift your footing to regain it, as MH senior editor Brett Williams, NASM does in the video above. Another key to proper form in the biceps curl is to keep your elbows locked to your sides. Don't let them travel forward. Many guys make that minute shift to bring the weight up to shoulder level—but that's counterproductive to what your focus is for the movement. Your goal is full contraction of the biceps muscle, not lifting the weight to a specific height. Use Partner Eccentrics to Get More From Each Rep If you're fortunate enough to have a training partner for your workout, you can crank up the muscle-building potential of every set by having them add manual resistance to the eccentric (lowering) phase of the first several reps. As demonstrated in the video above, MH fitness director Ebenezer Samuel, C.S.C.S. presses down slightly on the bar as Williams lowers it, forcing him to fight the added resistance to control the bar—and to keep his posture on point. Emphasizing the eccentric phase can optimize your muscle-building potential, especially if you're someone who typically concentrates exclusively on the concentric (lifting) phase of each rep. Regardless, having your partner add some eccentric resistance can also help expose weaknesses in your form, allowing you to shore it up for your standard reps, too. You Might Also Like The Best Hair Growth Shampoos for Men to Buy Now 25 Vegetables That Are Surprising Sources of Protein

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