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Why Most Diets Fail According to Weight Loss Surgeons—and What to Eat for Success

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Many individuals have attempted to trim their waistlines through calorie counting and frequent gym visits, yet often with little success. So, what’s the underlying issue?

According to Dr. Andrew Jenkinson, a consultant in bariatric surgery at University College London Hospital and author of Why We Eat (Too Much) and How to Eat (and Still Lose Weight), losing weight is less about the quantity of food consumed or the amount of exercise than previously thought.

He suggests that rather than obsessing over calorie counts and relentless gym sessions, a more practical approach to weight loss could be achieved by consuming foods that effectively regulate levels of the hormone leptin.

How does leptin function? What foods should fill your plate? Is there a straightforward way to combat cravings? Dr. Jenkinson addressed these topics in detail during our recent discussion.

BBC Science Focus: What is the global obesity crisis?

AJ: The Western world faces significant issues that are straining healthcare systems. In the U.S., about one-third of the population is considered morbidly obese, impacting their health drastically.

In Europe, the rate is around one-quarter. Many of these individuals face heightened risks of type 2 diabetes, hypertension, sleep apnea, joint problems, and certain cancers.

For the first time in history, life expectancy is declining due to obesity. New treatments, such as injections, are available, but they come at a hefty price.

Millions rely on them, and thus, obesity has become a major economic and health concern that requires urgent attention.

Obesity does not stem solely from the abundance of appealing, high-calorie food. These foods may act similarly to drugs, disrupting normal weight regulation mechanisms.

Wild animal populations face similar biological pathways, yet there’s no evidence that lions become inactive due to an oversupply of antelope.

Is the issue rooted in our hormones?

Yes. Leptin, often termed the ‘satiety hormone,’ is crucial in regulating the weight of wildlife and should ideally function in the same way for humans.

Leptin levels send signals to the brain’s weight control center, located in the hypothalamus. This hormone essentially dictates body weight: when leptin is detected, appetite diminishes and metabolism increases.

Leptin is produced by fat cells, meaning that higher leptin levels should correlate with reduced appetite and increased metabolism.

However, some food types can obstruct leptin signaling. While it’s well-known that sugar, refined carbohydrates, and processed foods contribute to obesity, the root cause isn’t merely their calorie content; it’s how they elevate insulin levels, which in turn inhibits leptin.

When leptin signaling fails, the brain loses track of whether we are overweight or underweight. You might look visibly overweight, but your brain might mistakenly signal that you need to eat more.

It’s akin to driving a vehicle and suddenly noticing the fuel gauge is empty. You panic and refuel, but the tank was never really empty to begin with—the gauge itself was faulty. Similarly, when leptin is blocked, your body undergoes a comparable malfunction.

What significance do calories hold for weight loss?

Calories are essential for survival, acting as energy units stored within plants. Plants predominantly store carbohydrates and energy within their cellular structures.

We utilize this energy for various bodily functions like heat generation, heartbeat, and movement. Interestingly, approximately 70% of the energy we consume is expended at rest, termed basal metabolism, which encompasses immune functions, maintaining body temperature, heart rate, and more.

There’s a common misconception among those who focus exclusively on calorie counts: the body can easily eliminate excess calories. For instance, you could adjust basal metabolism to burn an additional 600-700 calories daily through activity akin to enjoying a lavish three-course meal or engaging in a 10k run.

If you adopt a low-calorie diet, your body can also adapt to this lower intake, ultimately halting weight loss within weeks.

Moreover, while many individuals may overconsume, our bodies respond by increasing basal metabolism, leading to greater energy expenditure. This is a significant factor in the Western epidemic of hypertension, as our bodies heighten blood pressure to manage energy use.

Why do some people find it harder to lose weight than others?

This variation relates to the concept of a weight setpoint or weight anchor. Imagine it as an anchor that keeps a ship tethered to one location—similarly, your weight anchor dictates your body’s weight range.

Your weight anchor could be set within the “overweight” or “obese” zone. Even if you work hard at the gym or adhere to a low-calorie diet, your brain’s weight control center may pull you back to your setpoint.

This anchor is influenced by several factors, many of which you can change, but one is immutable: your genetics.

We all know individuals who remain naturally slim and can indulge in their favorite treats without gaining weight. However, about 25% to 33% of the population carries genes that predispose them to weight gain when exposed to Western dietary habits.

This genetic predisposition is heightened through easy access to sugar, refined carbohydrates, processed foods, fructose, vegetable oils, and more. Unfortunately, much of this unhealthy food is readily available in supermarkets, often overshadowing the fresh produce aisles.

This misunderstanding is prevalent among practitioners who advocate for calorie counting; it overlooks the fundamental principle that the type of food we consume acts on our bodies as a form of medicine.

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So, what should we be eating?

Remember, it’s about lifestyle changes rather than temporary dieting. Dieting implies short-term calorie restriction. However, if you comprehend how different foods impact your body like medications, you will naturally shed pounds. Avoid sugar, refined carbohydrates, and toxic vegetable oils that adversely affect insulin levels.

Opt for homemade meals, and without much struggle, your weight setpoints will begin to decrease. You may find you lose considerably more weight than through conventional exercise efforts. This doesn’t have to be a struggle or cause frustration.

For instance, you could effortlessly replace unhealthy snacks eaten while watching television with a plate of veggies sprinkled with a bit of salt. It is all about recognizing and transforming unhealthy habits into healthier alternatives.

Initially, giving up sugar or chocolate may trigger cravings. However, these can be managed through a technique called “Crave Surfing,” which involves acknowledging the craving without disregarding it. Focus on it, and you will find that these cravings will ebb and flow, becoming less intense over time.

What role should exercise play in weight loss?

If you can dedicate time to the gym for about an hour and a half, engaging in vigorous activities, you could potentially burn 1000 calories daily. Over six days a week, this can significantly impact your weight.

However, for most, this level of control is unattainable unless you are an athlete. Recommendations for 30 minutes of exercise, 3-4 times a week, have minimal effect on weight loss—you may only shed around 2 kilograms annually.

Just like limiting calories, exercise can enhance metabolism efficiency, causing the body to become more adept at conserving energy.

For example, if you engage in a 30-minute workout and burn about 400 calories, it may leave you feeling hungrier. Unless you maintain exceptional willpower, you are likely to consume those 400 calories back. Instead of burning these calories, your metabolism functions to regulate them.

The way to counter this effect involves a combination of calorie restriction and physical activity for optimal results. Our metabolism cannot typically adjust by more than 600 or 700 kilocalories a day. Hence, if you successfully reduce your intake beyond 1000 calories, weight loss is likely to follow—but it is a challenging task that can lead to fatigue and hunger.

This interview has been edited for clarity and brevity.

About our expert, Dr. Andrew Jenkinson

Andrew is a consultant specializing in obesity (weight loss) and general surgical procedures at University College London Hospital.

He is also the author of Why We Eat (Too Much) and How to Eat (and Still Lose Weight).

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Source: www.sciencefocus.com

Centuries-Old Equations Forecast Flow—Until They Fail

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The Navier-Stokes equations provide predictions for fluid flow

Liudmila Chernetska/Getty Images

Here’s an excerpt from the elusive newsletter of space-time. Each month, we let physicists and mathematicians take over your keyboard, sharing intriguing concepts from the universe’s vast expanse. You can Sign up for Losing Space and Time here.

The Navier-Stokes equations have approximately 200 years of history in modeling fluid dynamics, yet I still find them perplexing. It’s a strange feeling, especially given their significance in building rockets, creating medications, and addressing climate change. But it’s crucial to adopt a mathematical mindset.

The equations are effective. If they weren’t, we wouldn’t rely on them across such diverse applications. However, achieving results doesn’t guarantee comprehending them.

This situation parallels many machine learning algorithms. We can set them up, code for training, and observe outputs. Yet when we hit ‘GO’, they evolve, utilizing every step in their process to optimize outcomes. Thus, we often refer to them as “black boxes” for their obscure input-output mechanics.

The same uncertainty looms over the Navier-Stokes equations. While we possess a clearer understanding of the processes behind fluid dynamics compared to many machine learning methods—thanks to outstanding computational fluid dynamics solvers—these equations can still yield chaotic results. Identifying why this occurs is a significant problems in mathematics, linked to the Millennium Prize Problems, marking it as one of the seven most challenging unresolved questions. This makes deciphering the Navier-Stokes anomaly a million-dollar endeavor.

To grasp the challenge, let’s delve into the Navier-Stokes equation, particularly the adaptation for modeling “incompressible Newtonian fluids.” Think of it like water—conversely to air, it resists compression. (Though a more generalized version exists, I will focus on this variant, as it tied closely to my four-year doctoral thesis.)

These equations may seem daunting, but they stem from two well-established principles of the universe: mass conservation and Newton’s second law. For instance, the first equation describes the fluid parcel’s velocity, addressing how the fluid moves and alters shape without adding or removing mass.

The second equation is a complex representation of Newton’s famed equation, f = ma, applied to fluid parcels with density (ρ). It states that the momentum change rate of a fluid (left side) equals the applied force (right side). Simply put, the left side addresses mass acceleration; the right side deals with pressure (p), viscosity (μ), and exerted forces (f).

So far, so good. These equations derive from solid universal laws and function admirably—until they don’t.

2D liquid flows at right angles

NumberPhile

Consider a setup where a 2D fluid flows around a right angle. As the fluid approaches the corner, it is compelled to pivot along the channel. You could replicate this experiment in a laboratory setting, and many do around the globe. The fluid smoothly adapts its path, and life as we know it persists.

But what happens when you apply the Navier-Stokes equations to this scenario? These equations model fluid behavior and reveal how velocity, pressure, density, and related attributes progress over time. Yet, upon inputting this setup, the calculations suggest an infinite angular velocity. This isn’t just excessively large; it’s beyond comprehension—endless.

Model of 2D fluids’ flow at right angles using the Navier-Stokes equation

Keaton Burns, Dedalos

What’s happening? This result is absurd. I have conducted this experiment and observed that nothing unusual occurred. So, why did the equations fail? This is precisely where mathematicians get intrigued.

When I visit schools to discuss university applications, students invariably inquire about the admission processes at institutions like Oxford or Cambridge (I participate in selection interviews for both). I share my criteria for evaluating a strong applicant, emphasizing the importance of “thinking like a mathematician.” Breaking equations fascinates mathematicians for a reason.

It’s remarkably useful when a model operates successfully in 99.99% of cases, producing meaningful, viable results that tackle real-world problems. Despite its occasional failure, the Navier-Stokes equations remain indispensable for engineers, physicists, chemists, and biologists, aiding in solving intricate matters.

Designing a quicker Formula 1 car requires harnessing airflow dynamics. Developing a fast-acting drug necessitates understanding blood flow patterns. Predicting carbon dioxide’s effect on climate demands insights into atmospheric-oceanic interactions. Each of these scenarios pertains to fluid dynamics, making the Navier-Stokes equations critical across varied applications as they adapt to fill different mediums.

However, addressing a multitude of complex scenarios with unique dynamics necessitates elaborate equations. This complexity explains our limited understanding. Indeed, the Navier-Stokes equations are designated as Millennium Prize Problems. The Clay Mathematics Institute emphasizes the need for deeper insight as fundamental to resolving the million-dollar inquiry.

“Our vessel follows the waves as they ripple across the lake. Meanwhile, turbulent airflow continues to affect modern aircraft travel. Mathematicians and physicists feel that answers regarding turbulence and breezes lie in understanding the solutions to the Navier-Stokes equations. They seek to unveil the hidden secrets of these equations.”

How can we enhance our comprehension of equations? By experimenting until they break, something I often suggest to high school students. The cracks represent your gateway. Continue probing until the facade shatters, revealing the hidden treasures beneath.

Consider the historical context of solving quadratic equations, particularly in finding the value of x that satisfies the equation ax2 + bx + c = 0. Many will recognize this from their GCSE studies and understand that quadratic equations typically yield two roots.

This equation usually functions correctly, producing two solutions when substituting values for A, B, and C. However, certain conditions can render it ineffective, such as when b2 – 4AC <0, leading to non-existent square roots. I’ve identified circumstances where equations fail.

But how is this possible? Mathematicians from the 16th and 17th centuries proposed utilizing instances where quadratic equations seemed faulty to define “imaginary numbers,” stemming from negative square roots. This insight catalyzed the emergence of complex numbers and the rich mathematical frameworks that followed.

In essence, we often learn invaluable insights from failures more than from successful instances. For the Navier-Stokes equations, the rare occasions of malfunction occur when modeling infinite velocity in a right-angled fluid flow. Similar instances can arise when addressing vortex reconnection or soap membrane separation processes—real phenomena replicable in labs that produce infinite variable trends using Navier-Stokes.

Such apparent failures could uncover deeper truths about our mathematical models. Nevertheless, discussions remain open. It might indicate a level of detail issue in numerical simulations or faulty assumptions regarding individual liquid molecule behavior.

Conversely, these breakdowns may enlighten aspects of the Navier-Stokes equation’s inherent structure, bringing us a step closer to unlocking their mysteries.

Tom Crawford is a mathematician at Oxford University. speaker at this year’s New Scientist Live.

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Source: www.newscientist.com

What Real Survival Experts Say About Why Most Zombie Apocalypse Plans Fail

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The Zombie Apocalypse might sound like an ideal chance to eliminate your debts and catch up on reading 28 Years Later, but surviving in undead-infested wastelands isn’t a walk in the park.

When the Danny Boyle film debuted, we spoke with survival experts and professional preppers about what to do—and what not to do—and gathered their tips on navigating an apocalypse scenario. After all, the zombie apocalypse feels less like fiction now than it did a few years ago.

Stay Safe at Home

John Rammy, founder of The Prevent, a Survivalist Company, advises against investing in a bunker. “Instead of focusing on bunkers,” he explains,

“we should concentrate on reinforcing our current homes and communities. It’s essential that your doors can withstand multiple kicks. Your home is your fortress, providing a secure space during emergencies.”

He encourages contemplating how long one could stay inside their home. “If I had to lock myself in right now, how long could I last?” he asks.

“The initial goal should be a two-week supply, covering most emergencies like natural disasters. Some go further and prepare to last for six months. Personally, I am prepared to survive indefinitely, as I can grow food, find water, and purify it.”

Apocalypse © Grandfailure

Essential Supplies

As frightening as it sounds, being unprepared means being vulnerable. According to Ramey, stocking up on essential gear is crucial. “Consider Maslow’s hierarchy of needs: food, water, health, and communication,” he notes.

“First aid supplies are essential. Have sanitary products available—can you clean yourself properly? Water storage is vital. Generally, aim for one gallon of water per day.

“In the long run, do you know how to collect and store water? Make sure you have purification systems like filters or UV purifiers to ensure you can drink safely from natural sources.”

It’s also crucial to have a “bugout bag,” a pack of essential supplies ready for quick evacuation. Cameron Carlson, a survival expert and member of the Zombie Research Association, suggests the following items:

“Waterproof matches, an emergency blanket, a sleeping bag, freeze-dried food, a flashlight, batteries, a solar radio, a water purifier, a camping stove, a knife, a firearm, and a medical kit.”

“A useful tip is to include steel wool and a 9-volt battery. Touching the battery to the steel wool can ignite it, and steel wool is compact and lightweight.”

Ramey also recommends bicycles. “The bicycle is the ultimate bug-out vehicle,” he states. “It’s the most efficient human-powered machine ever made.

“Whenever experts watch The Walking Dead, one common complaint is that after eight years, people are still relying on gasoline vehicles. Gasoline tends to expire in six months. Though additives can extend its life, finding usable gasoline within a year can be challenging.”

Essential Skills

Having supplies is of no use if you lack the skills to utilize them effectively.

“Core skills include first aid and understanding how to treat injuries,” Ramey explains.

“Consider characters like Daryl from The Walking Dead. If he suffered an injury from a crossbow bolt, would you know how to assist? Modern society is advanced, yet we’ve lost centuries of survival skills over just a single century.”

“Many of our grandparents possessed at least rudimentary knowledge of treating wounds. Even standard first aid courses typically assume you can call for help—there’s often an expectation for emergency services to arrive promptly.”

Outdoor survival skills are equally vital. “Additionally,” Ramey adds, “many people no longer know how to navigate without technology. There’s a phenomenon known as ‘death by GPS.’ So, do you know how to read a map? Can you start a fire? Can you build a shelter for winter?

“Less obvious yet essential skills include conflict resolution and situational awareness. Are you aware of your surroundings? Do you know how to defuse a tense situation without resorting to violence?”

Man fleeing from zombies © Grandfailure

Where to Seek Refuge

There may come a time when you need to leave your home in search of safety. But where should you head?

If you’re in New York or London during a zombie apocalypse, you might want to head to the countryside, away from the crowds, Rammy suggests. “Yet even in such a scenario, isolation may become undesirable, as community becomes essential.”

“Community cooperation generally proves more beneficial than the stereotype of the lone wolf wandering off into the sunset with a shotgun slung over their shoulder.”

The prevailing belief that humanity will descend into chaos after an apocalyptic event is challenged by Michał Zalewski, author of A Practical Ending: A User’s Guide to the End of the World, who argues against this notion.

“Most individuals will likely suffer in silence rather than harming innocents,” he asserts. “The real danger during times of uncertainty is the tendency to react against ‘outgroups.’ However, in a zombie scenario, we have a defined enemy.

“And as we slow down, we are not machines. We need rest and recuperation. It’s impossible to master every necessary survival skill against every potential disaster.”

Dealing with Zombies

What about the zombies themselves? According to zombie aficionado Cameron Carlson, it all hinges on their nature—whether they’re fast and rabid (think 28 Days Later) or sluggish (like in The Walking Dead).

“If they are fast, there’s no outrunning them,” he admits. “Stealth becomes imperative, enabling you to maneuver away from their line of sight. If faced with fast-moving zombies, tactics are essential.”

“Against slower zombies, your main task is evasion.”

Carlson also suggests utilizing dogs for their acute sense of smell, which is superior to ours. “Dogs serve as excellent early warning systems. If your dog starts acting oddly—growling, showing teeth, or restlessly pacing—it’s a signal that something’s wrong.

Interestingly, a significant contrast exists between the UK’s and the US’s gun ownership cultures. How might this affect survival outcomes in a zombie apocalypse?

“It has its pros and cons,” Rammy states. “In cases where zombies are approaching, having a shotgun could be your last line of defense. In that sense, American gun culture provides certain advantages.

“However, it also means that in a society breaking down, many people will be armed. We’ve witnessed over the past two years that even during milder emergencies, a significant portion of the population can become erratic and difficult to manage. So, it’s a double-edged sword.”

Meet Our Experts

John Rammy is the founder of The Prevent, a Survivalist Company. He leverages his Silicon Valley background to advise the US government and Department of Defense on emergency preparedness technologies.

Cameron Carlson serves as a spokesperson for the Zombie Research Association. Currently active in the US Navy, he specializes in anti-piracy operations while studying disaster relief effectiveness and outdoor survival.

Michał Zalewski is a computer security expert and author of A Practical Ending: A User’s Guide to the End of the World.

This article was originally published in 2022

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Source: www.sciencefocus.com

COP29: Satellite detects methane leaks but “super emitters” fail to address issue

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Methane plume at least 4.8 kilometers long pours into the atmosphere south of Tehran, Iran

NASA/JPL-California Institute of Technology

The world now has more ways than ever to discover invisible methane emissions, which are so far responsible for a third of global warming. But methane “super emitters” take little action even when warned that they are leaking large amounts of the powerful greenhouse gas, according to a report released at the COP29 climate summit.

“We’re not seeing the transparency and urgency that we need,” he says. Manfredi Caltagirone director of the United Nations Environment Programme’s International Methane Emissions Observatory, recently launched a system that uses satellite data to alert methane emitters of leaks.

Methane is the second most important greenhouse gas to tackle after carbon dioxide, and more countries are pledging to reduce methane emissions to avoid short-term warming. At last year’s COP28 climate summit, many of the world’s largest oil and gas companies also pledged to “elimate” methane emissions from their operations.

Today, more and more satellites are beginning to detect methane leaks from the biggest sources of methane emissions, such as oil and gas infrastructure, coal mines, landfills, and agriculture. That data is critical to holding emitters accountable, he says. mark brownstein at the Environmental Defense Fund, an environmental advocacy group that recently launched its own methane sensing satellite. “But data alone won’t solve the problem,” he says.

The first year of the UN’s Methane Alert System shows a huge gap between data and action. Over the past year, this program has 1225 alerts issued When we saw plumes of methane from oil and gas infrastructure large enough to be detected from space, we reported them to governments and companies. To date, emitters have taken steps to control these leaks only 15 times, reporting a response rate of about 1 percent.

There are many possible reasons for this, Caltagirone says. Although emissions from oil and gas infrastructure are widely considered to be the easiest to deal with, emitters may lack the technical or financial resources and some methane sources may be difficult to shut down. there is. “It’s plumbing. It’s not rocket science,” he says.

Another explanation may be that emitters are not yet accustomed to the new alarm system. However, other methane monitoring devices have reported similar lack of response. “Our success rate is not that good,” he says Jean-François Gauthier GHGSat is a Canadian company that has been issuing similar satellite alerts for many years. “About 2 or 3 percent.”

Methane super emitter plume detected in 2021

ESA/SRON

There are also some success stories. For example, the United Nations issued several warnings this year to the Algerian government about a source of methane that has been leaking continuously since at least 1999, and whose global warming impact is equivalent to driving 500,000 cars a year. It is said to be equivalent. By October, satellite data showed it had disappeared.

But the big picture shows that monitoring is not yet leading to emissions reductions. “Simply showing a plume of methane is not enough to take action,” he says. rob jackson at Stanford University in California. The central problem, he sees, is that satellites rarely reveal who owns leaky pipelines or methane-emitting wells, making accountability difficult.

Methane is a major topic of discussion at the COP29 conference currently being held in Baku, Azerbaijan. a summit At a meeting on non-CO2 greenhouse gases convened by the United States and China this week, each country announced several measures on methane emissions. That includes a U.S. fee on methane for oil and gas emitters, a rule many expect the incoming Trump administration to roll back.

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Source: www.newscientist.com

Researchers have developed the ability to forecast which organs are most likely to fail earliest

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New research suggests that scientists may now be able to predict which organs will fail first, providing an opportunity for doctors to target aging organs earlier, before disease symptoms appear.

A study published in Nature found that one in five healthy adults over the age of 50 have at least one aging organ, increasing their risk of developing disease in that organ over the next 15 years. This discovery provides insight into the aging process of the body.

How does aging occur at different rates in the body?

We all have two ages: the chronological age that increases by one each year and the “biological age,” which is more flexible and changes based on health status. By studying biological signs within the body, scientists can determine a person’s biological age.

In a study of 5,678 people, researchers at Stanford Medicine determined the biological age of their organs by analyzing proteins in the blood, revealing that if a person’s organs are older than others of the same age, they are at a higher risk of disease.

Each organ in our body dies at a different rate, with certain proteins in the blood associated with specific organs. Scientists developed a machine learning algorithm using protein combinations to predict a person’s biological age and verified its accuracy on 4,000 people.

The study focused on the biological age of 11 important organs and revealed that people with rapidly aging organs are at a higher risk of disease and mortality. The research team hopes to replicate these findings in a larger group of people to detect which organs are aging at an accelerated rate, allowing for early treatment.

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Source: www.sciencefocus.com