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Ripped musclesThe metabolism is every drop of chemistry needed to keep the body going. And the bigger the body - whether that is ripped muscles or too much belly fat - the more energy it will take to run.

The study, published in the journal Science, found four phases of metabolic life:birth to age one, when the metabolism shifts from being the same as the mother's to a lifetime high 50% above that of adults a gentle slowdown until the age of 20, with no spike during all the changes of pubertyno change at all between the ages of 20 and 60a permanent decline, with yearly falls that, by 90, leave metabolism 26% lower than in mid-life

Other surprises came from what the study did not find. There was no metabolic surge during either puberty or pregnancy and no slowdown around the menopause.

While researchers have known for decades that the body undergoes various metabolic and hormonal changes while it’s losing weight, the Australian team detected something new. A full year after significant weight loss, these men and women remained in what could be described as a biologically altered state. Their still-plump bodies were acting as if they were starving and were working overtime to regain the pounds they lost. For instance, a gastric hormone called ghrelin, often dubbed the “hunger hormone,” was about 20 percent higher than at the start of the study. Another hormone associated with suppressing hunger, peptide YY, was also abnormally low. Levels of leptin, a hormone that suppresses hunger and increases metabolism, also remained lower than expected. A cocktail of other hormones associated with hunger and metabolism all remained significantly changed compared to pre-dieting levels. It was almost as if weight loss had put their bodies into a unique metabolic state, a sort of post-dieting syndrome that set them apart from people who hadn’t tried to lose weight in the first place.

Too Much High-Intensity Exercise May Be Bad for Your Health

A new study hints that excessive HIIT may harm your mitochondria, the energy generators found in every cell of your body.

If high-intensity exercise is good for us, is more necessarily better?

Scientists at Stanford University and the J. Craig Venter Institute have developed the first software simulation of an entire organism, a humble single-cell bacterium that lives in the human genital and respiratory tracts.

the work was a giant step toward developing computerized laboratories that could carry out many thousands of experiments much faster than is possible now, helping scientists penetrate the mysteries of diseases like cancer and Alzheimer’s.

cancer is not a one-gene problem; it’s a many-thousands-of-factors problem.”

A variety of methods have been developed over the past few decades to allow mapping of the functioning human brain. Two basic classes of mapping technique have evolved: those that map (or localise) the underlying electrical activity of the brain; and those that map local physiological or metabolic consequences of altered brain electrical activity. Among the former are the non-invasive neural electromagnetic techniques of electroencephalography (EEG) and magnetoencephalography (MEG). These methods allow exquisite temporal resolution of neural processes (typically over a 10–100 ms time scale), but suffer from poor spatial resolution (between 1 and several centimetres). Functional MRI (fMRI) methods are in the second category. They can be made sensitive to the changes in regional blood perfusion, blood volume (for example, using injected magnetic resonance contrast agents), or blood oxygenation that accompany neuronal activity. Blood oxygenation level dependent (BOLD) fMRI, which is sensitive primarily to the last of these variables, allows an image spatial resolution that is of the order of a few millimetres, with a temporal resolution of a few seconds (limited by the haemodynamic response itself). An accessible and more detailed introduction to the technique than is possible in this brief review is found in a recent book.1

Methods such as positron emission tomography (PET) provide an absolute measure of tissue metabolism. In contrast, BOLD fMRI can at present be used only for determining relative signal intensity changes associated with different cognitive states during a single imaging session. The most time efficient approach for comparing brain responses in different states during the imaging experiment is the “block” design19 (fig 3). This design uses relatively long alternating periods (for example, 30 seconds), during each of which a discrete cognitive state is maintained. In the simplest form, there may only be two such states, which are alternated throughout the experiment in order to ensure that variations arising from fluctuations in scanner sensitivity, patient movement, or changes in attention have a similar impact on the signal responses associated with both states.

The human microbiota consists of the entire collection of microbes that live in and on the body. In fact, there are 10 times as many microbial inhabitants of the body than there are body cells. Study of the human microbiome is inclusive of inhabitant microbes as well as the entire genomes of the body's microbial communities. These microbes reside in distinct locations in the ecosystem of the human body and perform important functions that are necessary for healthy human development.

Microbes of the BodyMicroscopic organisms that inhabit the body include archaea, bacteria, fungi, protists, and viruses. Microbes start to colonize the body from the moment of birth. An individual's microbiome changes in number and type throughout his or her lifetime, with the numbers of species increasing from birth to adulthood and decreasing in old age. These microbes are unique from person to person and can be impacted by certain activities, such as hand washing or taking antibiotics. Bacteria are the most numerous microbes in the human microbiome.

Human skin is populated by a number of different microbes that reside on the surface of the skin, as well as within glands and hair. Our skin is in constant contact with our external environment and serves as the body's first line of defense against potential pathogens. Skin microbiota help to prevent pathogenic microbes from colonizing the skin by occupying skin surfaces. They also help to educate our immune system by alerting immune cells to the presence of pathogens and initiating an immune response

Every living thing is a pulse. We quicken, then we fade. There is a deep beauty in this, but deeper down, inside every plant, every leaf, inside every living thing (us included) sits a secret.

Everything alive will eventually die, we know that, but now we can read the pattern and see death coming. We have recently learned its logic, which "You can put into mathematics," says physicist Geoffrey West. It shows up with "extraordinary regularity," not just in plants, but in all animals, from slugs to giraffes. Death, it seems, is intimately related to size.

Life is short for small creatures, longer in big ones.

Mitochondria are our cells' energy dynamos. Descended from bacteria that colonized other cells about 2 billion years, they get flaky as we age.

While it's not clear why our mitochondria fade as we age, evidence suggests that it leads to everything from heart failure to neurodegeneration,

Recent research suggests it may be possible to reverse mitochondrial decay with dietary supplements that increase cellular levels of a molecule called NAD (nicotinamide adenine dinucleotide).

As part of a lifelong experiment on circadian rhythms, Sothern, now 69, is trying to confirm or reject a widely held belief: Many people feel that time flies by more quickly as they age.

So far, Sothern's results are inconclusive

"I'm tending now to overestimate the minute more than I used to," he tells me. But then again, he had detected a similar pattern — more overestimates — in the 1990s, only to have his estimates fall in the 2000s. "Time estimation isn't a perfect science," he says.

Winning stimulates dopamine, serotonin and oxytocin. Just watching competition stimulates these happy chemicals through our mirror neurons.

Happy chemicals are stimulated by behaviors that promote survival in the state of nature.

 Dopamine is the good feeling of getting a reward the meets your needs.

in order to pursue their intellectual adventures, children need a secure social base:

The way to discover a terrifying longing is to liberate yourself from the self-censoring labels you began to tell yourself over the course of your mis-education. These formulas are stultifying

The lesson from childhood, then, is that if you want to win the war for attention, don’t try to say “no” to the trivial distractions you find on the information smorgasbord; try to say “yes” to the subject that arouses a terrifying longing, and let the terrifying longing crowd out everything else.

we fail to notice that food marketers use synthetic vitamins to sell unhealthful products. Not only have we become dependent on these synthetic vitamins to keep ourselves safe from deficiencies, but the eating habits they encourage are having disastrous consequences on our health.

vitamins spread from the labs of scientists to the offices of food marketers, and began to take on a life of their own.

Nutritionists are correct when they tell us that most of us don’t need to be taking multivitamins. But that’s only because multiple vitamins have already been added to our food.

paleontologists documented one of the most dramatic transitions in human evolution. We might call it the Brain Boom. Humans, chimps and bonobos split from their last common ancestor between 6 and 8 million years ago.

Starting around 3 million years ago, however, the hominin brain began a massive expansion. By the time our species, Homo sapiens, emerged about 200,000 years ago, the human brain had swelled from about 350 grams to more than 1,300 grams.

n that 3-million-year sprint, the human brain almost quadrupled the size its predecessors had attained over the previous 60 million years of primate evolution.

Despite extreme heat, no light, minuscule nutrition and intense pressure, scientists estimate this subterranean biosphere is teeming with between 15bn and 23bn tonnes of micro-organisms, hundreds of times the combined weight of every human on the planet.

Researchers at the Deep Carbon Observatory say the diversity of underworld species bears comparison to the Amazon or the Galápagos Islands, but unlike those places the environment is still largely pristine because people have yet to probe most of the subsurface.

“It’s like finding a whole new reservoir of life on Earth,” said Karen Lloyd, an associate professor at the University of Tennessee in Knoxville. “We are discovering new types of life all the time. So much of life is within the Earth rather than on top of it.

As a psychiatrist, I’ve long wondered why some people get ill in the face of stress and adversity — either mentally or physically — while others rarely succumb.

not everyone gets PTSD after exposure to extreme trauma, while some people get disabling depression with minimal or no stress

What makes people resilient, and is it something they are born with or can it be acquired later in life?

Piper, Mijares and their team published a description of the foot bone in 2010. They knew it was the oldest human remain in the Philippines, dated to 67,000 years ago, based on the amount of the radioactive element uranium in the fossil

Mijares returned to Callao Cave and uncovered more remains in 2011 and 2015. All told, the scientists pulled a dozen fossilized parts from the cave — teeth, a thigh bone, finger bones and foot bones, representing three individuals. Attempts to extract DNA from the remains were unsuccessful.

The body parts are diminutive, suggesting Homo luzonensis grew no more than four feet tall. Its molars have modern shapes. The way its leg muscle attached to its thigh bone is “distinctively human,”

a high-fiber diet came with a 40-percent lower than average risk of heart disease. Fiber also seems to protect against metabolic syndrome.

One of the mechanisms behind these benefits appears to be that fiber essentially feeds the microbes in our guts, encouraging diverse populations. Those microbes are implicated in a vast array of illnesses and wellbeing. A diet heavy on meat and dairy is necessarily lower on fiber.

The basic idea behind Paleo is that humans evolved under certain circumstances over millennia, and then those circumstances changed tremendously in the last century, and our bodies did not keep pace. We find ourselves sedentary and overfed on amalgamations that distort our body’s expectations of “food.”

The scientists during Atwater’s era saw the human digestive system as a single engine producing a predictable quantity of energy from a given amount of fuel.

Yet the human gut contains a multitude of engines, and they interact with each other in ways science is just beginning to unravel. Over the past 15 years, a fast-growing body of literature suggests that the gut microbiome—the trillions of microbes that live inside us—shapes the way we metabolize food and may play an important role in how we gain weight.

Antibiotics, it turns out, reconfigure your gut’s balance in favor of microbes that help us store food as body fat.

experts say some of the strongest protective effects may be with Type 2 diabetes, Parkinson’s disease, and liver conditions such as cirrhosis, liver cancer and chronic liver disease. For example, having about five cups of coffee a day, instead of none, is correlated with a 30 percent decreased risk of Type 2 diabetes, according to a meta-analysis of 30 studies.

“We don’t know for sure if coffee is the cause of the health benefits,” said Jonathan Fallowfield, a professor at the University of Edinburgh, and co-author of the British Medical Journal review. “These findings could be due to other factors or behaviors present in coffee drinkers.”

A study in JAMA Internal Medicine examined the coffee habits of nearly 500,000 people in the U.K. and found that it didn’t matter if they drank one cup or chain-drank eight — regular or decaf — or whether they were fast metabolizers of coffee or slow. They were linked to a lower risk of death from all causes, except with instant coffee, the evidence was weaker.

the virus appears to start in peripheral areas on both sides of the lung and can take a while to reach the upper respiratory tract, the trachea and other central airways.

that pattern helps explain why in Wuhan, where the outbreak began, many of the earliest cases were not identified immediately.

The initial testing regimen in many Chinese hospitals did not always detect infection in the peripheral lungs, so some people with symptoms were sent home without treatment.