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The Right Bacteria Can Turn Off a Sweet Tooth

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We have a lot of control of our day to day lives; we get to choose where we go, who we see, and what we eat. But those decisions are often shaped by unseen forces, including some right under our noses (and all over our bodies for that matter). Scientists working with E. coli bacteria in mice say a taste for sweets might literally come from our guts. They present their findings this week in Florida at the annual meeting of the Association for Chemoreception Sciences. 

Some of the bacteria on our bodies are a force for good: they help us digest our food and stay healthy. Some are less helpful. Science is really just beginning to discover the many ways we interact with our bacteria. Some of our choices, like smoking, eating a low-fiber diet, or using deodorant, affect our bacteria. But the reverse may also be true: our bacteria could affect our choices.

This all has to do with the fact that these tiny organisms get hungry. Those in your digestive tract have it pretty easy: They just chow down on the food you shove in there. Some prefer fats, while others thrive on sugar. And if there are enough of them, what they want may become what you want.

“In our field, we are starting to think about how hormones and different factors affect the taste system, even at the level of taste buds, and contribute to obesity,” presenter Lynnette McCluskey said in a press statement. McCluskey is a neuroscientist at Augusta University's Medical College of Georgia. "Identifying the taste, whether it's sweet or not, is the first step in feeding. We wanted to know if you change the environment in the gut, what happens to the taste system."

McCluskey and her colleagues had previously found that they could reduce a mouse’s ability to identify sweet tastes by dropping a molecule called lipopolysaccharide (LPS) on its tongue. The LPS was extracted from the cell wall of E. coli bacteria, then detoxified so the mice would not get sick. 

For this experiment, the researchers wanted to find out if actually ingesting LPS could actually make mice lose interest in sweet flavors. They implanted small doses of detoxified LPS in each mouse’s gut, then offered them access to four sweeteners: glucose, sucrose (table sugar), saccharin (a.k.a. Sweet’n Low), and acesulfame potassium (a.k.a. Sweet One).  

Within 15 hours, mice dosed with LPS had higher levels of a hormone called leptin, which tells us when to stop eating. One week later, those mice had lost their preference for sweets. Even the number of sweet taste receptors on their tongues had decreased. It wasn’t that they’d lost their appetites altogether; the mice were still healthy and ate other food as they had before. It was just that sugar had lost its appeal. Yet seven days later, the rodents’ taste for sweetness had returned. 

The researchers were left with a number of questions. How did LPS in the gut cause a mouse’s body to make more leptin? Why did it take seven days to kick in? Why did it stop? And why leptin? "There may be other gut hormones involved as well,” said McCluskey, “but we know that leptin works.”

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Scientists Find a Possible Link Between Beef Jerky and Mania
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Scientist have discovered a surprising new factor that may contribute to mania: meat sticks. As NBC News reports, processed meats containing nitrates, like jerky and some cold cuts, may provoke symptoms of mental illness.

For a new study, published in the journal Molecular Psychiatry, scientists surveyed roughly 1100 people with psychiatric disorders who were admitted into the Sheppard Pratt Health System in Baltimore between 2007 and 2017. They had initially set out to find whether there was any connection between certain infectious diseases and mania, a common symptom of bipolar disorder that can include racing thoughts, intense euphoria, and irritability.

While questioning participants about their diet, the researchers discovered that a significant number of them had eaten cured meats before their manic episodes. Patients who had recently consumed products like salami, jerky, and dried meat sticks were more likely to be hospitalized for mania than subjects in the control group.

The link can be narrowed down to nitrates, which are preservatives added to many types of cured meats. In a later part of the study, rats that were fed nitrate-free jerky acted less hyperactive than those who were given meat with nitrates.

Numerous studies have been published on the risks of consuming foods pumped full of nitrates: The ingredient can lead to the formation of carcinogens, and it can react in the gut in a way that promotes inflammation. It's possible that inflammation from nitrates can trigger mania in people who are already susceptible to it, but scientists aren't sure how this process might work. More research still needs to be done on the relationship between gut health and mental health before people with psychiatric disorders are told to avoid beef jerky altogether.

[h/t NBC News]

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6 Signs You're Getting Hangry
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Hangry (adjective): Bad-tempered or irritable as a result of hunger. This portmanteau (of hungry and angry) is not only officially recognized as a word by the Oxford English Dictionary, but it's also recognized by health experts as a real physiological state with mood-altering consequences.

That hangry feeling results from your body's glucose level dropping, putting you into a state of hypoglycemia, or low blood sugar. Glucose is the body's primary source of energy, so when you don't have enough, it affects your brain and other bodily functions, including the production of the hormones insulin and glucagon, which help regulate blood sugar. Check out the symptoms below to see if you've crossed over into the hanger danger zone.

1. IT TAKES EVERYTHING IN YOUR POWER JUST TO KEEP YOUR EYES OPEN.

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Glucose equals energy, so when your blood sugar levels are low, you may start wishing you were back in bed with the shades drawn. If you start feeling sluggish or tired even though you’re well-rested, you might just need to eat something.

2. THE EASIEST ITEM ON YOUR TO-DO LIST SEEMS LIKE AN IMPOSSIBLE TASK …

It’s hard to concentrate when all you can think about is whether you're going to order the fish or beef tacos for lunch. The distraction goes beyond fantasies about food, though. The brain derives most of its energy from glucose, so when it's low on fuel, a serious case of brain fog can set in. Confusion and difficulty speaking are among the more serious symptoms you may experience when you're hangry.

3. … AND YOU HAVE A BAD CASE OF WORD VOMIT.

Blame this on brain fog too. The gray matter in your noggin goes a little haywire when blood sugar is in short supply. That's why you may start stuttering or slurring your words. You might also have difficulty finding your words at all—it can feel like your mouth and brain are disconnected.

4. YOU’RE SHAKING LIKE A LEAF AND FEEL LIGHTHEADED.

Tremors and dizziness are both signs that you should pay closer attention to your body, which is screaming, "Feed me!" Once again, low blood sugar is often the culprit of trembling hands and feeling faint, and exhaustion and stress make the symptoms worse.

5. YOUR COWORKERS SEEM ESPECIALLY ANNOYING.

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You’re tense and irritable, and it’s starting to show. Hunger causes your body to release cortisol and adrenaline, the same hormones responsible for stress. This can put you on edge and lower your tolerance for other people’s quirks and irksome habits, which suddenly seem a lot less bearable.

6. YOU SNAPPED AT YOUR FRIEND OR PARTNER FOR NO GOOD REASON.

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Not only are you irritable, but you’re more likely to lash out at others because of it. The doses of adrenaline and cortisol in your body can induce a fight-or-flight response and make you go on the attack over matters that—if you had some food in you—would seem unimportant.

So what should you do if these descriptions sound all too familiar? Eat a snack, pronto—one with complex carbohydrates, lean protein, and healthy fats. The first one brings up your blood sugar level, and the other two slow down how fast the carbohydrates are absorbed, helping you to avoid a sugar crash and maintain a normal blood sugar level. Eating small meals every few hours also helps to keep hanger at bay.

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