Health & Fitness

01/09/20

Experiments in worms reveal the molecular damage caused by DEHP, a chemical commonly used to make plastics flexible. DEHP interferes with proper cell division during egg formation, leads to excessive DNA breakage, alters chromosome appearance. Abnormalities help explain known link between DEHP and human birth defects, male infertility. If replicated in further research, the insights can help inform regulatory changes, consumer choice.

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Less-than-perfect kidneys can be successfully used for transplants, study shows

One-fourth of children with autism are undiagnosed

BPA replacement, BPS, hinders heart function, study reveals

Parents aren't powerless when it comes to sleep-deprived teenagers

Teenagers in the US simply don't get enough shut eye. The consequences of this sleep deprivation epidemic are extensive and include increasing rates of anxiety and depression among adolescents, as well as suicidal thoughts and actions. Researchers found that a simple and timeworn solution yields solid results: a clear bedtime that parents consistently enforce.

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'Bilingual' molecule connects two basic codes for life

Bandage material helps stop bleeding without adhering to the wound

Contaminating a fake rubber hand could help people overcome OCD, study suggests

Researchers test hearing by looking at dilation of people's eyes

What are ultra-processed foods and are they bad for our health?

You hear it all the time: the advice to “eat less processed food.” But what is processed food? For that matter, what is minimally processed food or ultra-processed food? And how do processed foods affect our health?

What are processed and ultra-processed foods?

Unprocessed or minimally processed foods are whole foods in which the vitamins and nutrients are still intact. The food is in its natural (or nearly natural) state. These foods may be minimally altered by removal of inedible parts, drying, crushing, roasting, boiling, freezing, or pasteurization, to make them suitable to store and safe to consume. Unprocessed or minimally processed foods would include carrots, apples, raw chicken, melon, and raw, unsalted nuts.

Processing changes a food from its natural state. Processed foods are essentially made by adding salt, oil, sugar, or other substances. Examples include canned fish or canned vegetables, fruits in syrup, and freshly made breads. Most processed foods have two or three ingredients.

Some foods are highly processed or ultra-processed. They most likely have many added ingredients such as sugar, salt, fat, and artificial colors or preservatives. Ultra-processed foods are made mostly from substances extracted from foods, such as fats, starches, added sugars, and hydrogenated fats. They may also contain additives like artificial colors and flavors or stabilizers. Examples of these foods are frozen meals, soft drinks, hot dogs and cold cuts, fast food, packaged cookies, cakes, and salty snacks.

According to a study published in The BMJ, ultra-processed foods are the main source (nearly 58%) of calories eaten in the US, and contribute almost 90% of the energy we get from added sugars.

How do processed foods affect our health?

A recent study published in the journal Cell Metabolism compared the effects of an ultra-processed diet to the effects of an unprocessed diet on calorie intake and weight gain. The study involved 20 heathy, overweight adults staying at a medical facility. Each study participant received an ultra-processed diet and an unprocessed diet for 14 days each. During each diet phase, the study subjects were presented with three daily meals and were instructed to consume as much or as little as desired. Up to 60 minutes was allotted to consume each meal, with snacks (either ultra-processed or unprocessed, depending on the study phase) available throughout the day.

The meals were matched across the diets for total calories, fat, carbohydrate, protein, fiber, sugars, and sodium. The big difference was the source of calories: in the ultra-processed diet phase, 83.5% of calories came from ultra-processed food; in the unprocessed diet phase, 83.3% of calories came from unprocessed foods.

The researchers found that study subjects consumed about 500 more calories per day on the ultra-processed diet versus the unprocessed diet. The ultra-processed diet period was marked by an increased intake of carbohydrate and fat, but not protein. Participants gained on average two pounds during the ultra-processed diet phase, and lost two pounds during the unprocessed diet phase. The authors concluded that limiting ultra-processed foods may be an effective strategy for preventing and treating obesity.

The study did have several limitations. For one thing, with only 20 participants, this was a very small study. For another, there was significant variation in individual responses to the two diets. Eleven people gained extreme weight on the ultra-processed diet — as much as 13 pounds over 14 days — while a few participants saw no weight gain. It’s also unclear how generalizable the results are to a wider population, because the study did not include people with chronic diseases such as heart disease or diabetes. In addition, the study was done in a clinical research setting, which could have affected their eating behavior (the study subjects may have been more isolated and bored than in their natural environments).

Another study, this one published in The BMJ, examined representative dietary records of more than 100,000 French adults over a five-year period. They found that those who consumed more ultra-processed foods had higher risks of cardiovascular disease, coronary heart disease, and cerebrovascular disease. These results remained statistically significant even after the researchers adjusted for the nutritional quality of the diet (considering factors such as the amount saturated fat, sodium, sugar, and dietary fiber in the diets). Although large observational studies do not prove cause and effect, the research does suggest an association between ultra-processed diets and heart disease.

Learn to identify processed foods

Whenever possible, try to avoid or limit ultra-processed foods. Consider the examples in this table to help you quickly determine if a food is minimally processed, processed, or ultra-processed.

Minimally processed	Processed	Ultra-processed
Corn	Canned corn	Corn chips
Apple	Apple juice	Apple pie
Potato	Baked potato	French fries
Carrot	Carrot juice	Carrot cake
Wheat	Flour	Cookies

The post What are ultra-processed foods and are they bad for our health? appeared first on Harvard Health Blog.

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Peering into the genome of brain tumor

Scientists have created a machine learning method for classifying the mutations of glioma brain tumors based on MR images alone. Thus far, classification has only been possible by tissue sampling during surgery. The new method is noninvasive, may remove the need for a tissue sample and help accelerate delivery of treatment for patients.

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How bacterial evolution of antibiotic arsenals is providing new drug blueprints

Scientists have taken their cue from nature to provide new options for drug designers seeking to hold back the global threat of antimicrobial resistance. The scientists have blueprinted how two antibiotics produced by bacteria function against methicillin-resistant Staphylococcus aureus (MRSA) to pinpoint potential new drug targets.

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Excess Body Fat Can Age Your Brain Faster Than Muscle

Staying fit as you age is about far more than aesthetics. Increasing research shows that maintaining healthy levels of body fat and greater muscle mass has an effect on your brain health and even your rate of cognitive aging. It’s known, for instance, that being obese in midlife and early late-life is associated with worse cognitive aging.¹

What’s more, the amount of muscle and fat you have may be a more important factor in how your level of fluid intelligence decreases over time than your chronological age. Your chronological age, i.e., your age in years, is just a numerical measurement, but your real age is your biological age as dictated by your choices and habits, as well as your modifiable risk factors like levels of muscle and fat.

While many people tend to gain fat and lose muscle mass as they age, this can be largely combated by staying active and eating right — lifestyle choices that will influence your cognitive function significantly.

More Muscle, Less Fat Protects Your Brain

In a study by Iowa State researchers, data from 4,431 adults were examined to compare levels of lean muscle mass, abdominal fat and subcutaneous fat with changes in fluid intelligence — the ability to solve problems in new situations — over a six-year period.^2,³

Those with higher amounts of abdominal fat had worse fluid intelligence with age, while those with greater muscle mass were more protected against such declines. In fact, women who had greater muscle mass tended to have better scores in fluid intelligence during the study period.

Study co-author Auriel Willette, assistant professor of food science and human nutrition at Iowa State University, said in a news release, "Chronological age doesn't seem to be a factor in fluid intelligence decreasing over time. It appears to be biological age, which here is the amount of fat and muscle."⁴

What’s more, the study revealed a link between the immune system and how changes in fat levels affect cognition. Previous research suggests a higher body mass index (BMI) leads to greater immune system activity in the blood, which in turn activates the immune system in the brain, with a negative outcome on cognitive function.⁵

The featured study also found that changes in white blood cells called lymphocytes and eosinophils explained the link between abdominal fat and worsening fluid intelligence in women. In men, basophils, another type of white blood cell, were linked to about half of the link between fat levels and fluid intelligence, the study found.⁶

“Lymphocytes, eosinophils, and basophils may link adiposity to cognitive outcomes,” the researchers explained.⁷ Similar research has revealed that overweight and obese individual have greater brain atrophy in middle-age, corresponding with an increase in brain age of 10 years.⁸

How Obesity Affects Your Brain

Obesity has multiple effects on the brain, including anatomically speaking. Obese individuals may have reduced gray matter in brain regions such as the hippocampus, prefrontal cortex and other subcortical regions. Atrophy in the hippocampus, in turn, has been linked to Alzheimer’s disease.⁹

Gray matter is the outer layer of the brain associated with high-level brain functions such as problem-solving, language, memory, personality, planning and judgment. Even in elderly people who are otherwise cognitively normal, obesity is associated with measureable deficits in brain volume in the frontal lobes, anterior cingulate gyrus, hippocampus, and thalamus compared to individuals with a normal weight.¹⁰

Further research published in Radiology found that obesity may lead to alterations in brain structure, shrinking certain regions.¹¹ Among men, higher total body fat percentage was linked to lower brain gray matter volume. Specifically, 5.5% greater total body fat percentage was associated with 3,162 mm3 lower gray matter volume.

Among men, 5.5% greater total body fat was also associated with 27 mm3 smaller globus pallidus volume, an association also seen in women. In women, 6.6% greater total body fat percentage was associated with 11.2 mm3 smaller globus pallidus volume.

The globus pallidus is a brain region that plays a role in supporting a range of functions, including motivation, cognition and action.¹² Obesity was also associated with changes in white matter microstructure, which may be related to cognitive function.¹³

Cognitively speaking, there’s also a strong link between obesity and deterioration in cognitive function, as well as to other brain disorders such as dementia, anxiety and depression. Further, past research has linked midlife obesity with an increased risk of mild cognitive impairment, changes in short-term memory and executive functioning and dementia.¹⁴

Obesity-Associated Health Problems Also Harm Your Brain

Obesity’s effects on brain health are also due to its associated health problems, including heart disease, diabetes and atherosclerosis, each of which can have its own deleterious effects on your brain. For instance, as noted in Frontiers in Neuroscience:¹⁵

“Obesity-derived vascular problems, such as atherosclerosis and arteriosclerosis, which are systemic diseases, are known to affect the steady blood flow of vessels that feed the brain, thus contributing to cognitive impairment or even stroke, where large areas of the brain die due to the stop in the blood flow of a major brain artery caused by a blood clot.”

In terms of diabetes, of which obesity is a key risk factor, having this condition in midlife is associated with a 19% greater cognitive decline over 20 years compared with not having the condition.¹⁶ Even those with prediabetes had significantly greater cognitive decline than those without.

Indeed, “Epidemiological studies have linked type-2 diabetes mellitus with cognitive impairment and dementia, with insulin resistance and hyperglycemia as the probable mechanistic links,” researchers noted.¹⁷

Coming full circle, eating a highly processed, junk food diet not only increases obesity risk but also can lead to normal but elevated blood sugar levels that, in turn, can lead to impaired glucose metabolism and Type 2 diabetes. Both diabetes and higher fasting glucose levels are linked with lower total brain volume.¹⁸

Impaired glucose metabolism is then associated with neurodegeneration that impairs cognitive function. This connection begins not in old age but much earlier, such that following a healthy lifestyle in young adulthood may be protective against cognitive decline later.¹⁹

The Inflammation Connection

Obesity can trigger chronic inflammation in your body, and chronic inflammation in your brain (neuroinflammation) is known to impair neurogenesis, your brain's ability to adapt and grow new brain cells. It’s also linked to neurodegenerative disorders such as Alzheimer’s disease (AD), and it’s been suggested that “Obesity may serve as an amplifier or initiator of the chronic inflammation observed in AD patients.”²⁰

Further, higher levels of inflammatory markers have also been associated with lower brain volume, including “greater atrophy than expected for age.”²¹ Excess body fat, particularly visceral fat, is also related to the release of proteins and hormones that can cause inflammation, which in turn can damage arteries and enter your liver, affecting how your body breaks down sugars and fats.

According to a study in the Annals of Neurology, “[A]dipose-tissue derived hormones, such as adiponectin, leptin, resistin or ghrelin, could also play a role in the relation between adipose tissue and brain atrophy.”²² Further, obesity may also be associated with lower volume in brain regions that regulate food-reward circuitry,²³ possibly influencing overeating.

Strength Training Is Good for Your Brain

While obesity takes a toll on your brain, increased muscle mass protects it, which is likely one reason why strength training has been found to be beneficial for your brain. In other words, your body’s physical strength may serve as a marker of your brain power.

In fact, strength training is known to trigger beneficial neurobiological processes,²⁴ leading to positive functional brain changes, including in the frontal lobe, with corresponding improvements in executive functions. One systematic review even found that strength training led to less white matter atrophy in the brain, with researchers noting:²⁵

“Taken together, during aging processes, a substantial decline in muscular strength, especially in lower limb muscles, occurs, and accumulating evidence suggests that lower muscular strengths are linked to poorer cognitive performance.

Hence, resistance (strength) exercises (a single bout of resistance exercise, also referred to as acute exercise) and resistance (strength) training (more than one resistance exercise session, also referred to as chronic exercise … ) seem to be promising activities to ensure the preservation of physical functioning and cognitive functions with aging.”

Regular strength training, in addition to other forms of exercise and daily activity, is an important strategy for keeping your brain sharp and may help to offset some of the cognitive decline that occurs with age.

Avoid Obesity and Protect Your Brain With a Ketogenic Diet

While obesity may accelerate neurodegeneration, regular exercise to increase your muscle mass will be protective. Further, eating a ketogenic diet will help protect your brain from free radical damage and will supply the cells with preferred fuel while also helping you to lose weight and avoid obesity.

A ketogenic diet is high in healthy fats and low in net carbohydrates (total carbs minus fiber), prompting your body to start burning fat as its primary fuel, rather than sugar. This produces ketones, which not only burn efficiently but are also a superior fuel for your brain. Ketones also generate fewer reactive oxygen species (ROS) and less free-radical damage.

One of the simple strategies you can implement is to take ketone precursors like refined MCT oils of caprylic acid (C-8). The eight-chain carbon fats are readily converted to ketones. I personally use up to 5 ounces of our Ketone Energy when I have maxed out my protein and carb intake and need a source of healthy clean fat. This keeps my ketone level around 1 to 2.0 mmol/l. Just recognize that you have to build up to a high dose of MCT oil slowly or you will have problems with loose stools.

Recent studies have also demonstrated the benefits of nutritional ketosis for brain health. In one, researchers found a ketogenic diet improved neurovascular function, in part by improving your gut microbiome.²⁶

In a second study, the researchers concluded a ketogenic diet acted as a veritable "fountain of youth" in their animal study by significantly improving neurovascular and metabolic functions, compared to the animals eating an unrestricted diet.²⁷ Releasing ketones into your bloodstream helps preserve brain function and protects against cognitive impairment and other neurodegenerative diseases.²⁸

KetoFasting, the program I developed and detail in my book, "KetoFast: A Step-By-Step Guide to Timing Your Ketogenic Meals," combines a cyclical ketogenic diet and intermittent fasting with cyclical partial fasting to optimize health and longevity.

Not only can KetoFasting help you to lose weight, but your cognition typically improves thanks to the biological cleansing and regeneration that occurs throughout your body, including your brain.

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Does a Study Change What We Know About Blue Light?

Artificial light is a relatively new development in terms of human evolution. Before we could create "day" out of night, humans woke up with the sun and went to bed when the sun set. Some studies suggest that before artificial light, humans experienced biphasic sleep; they slept in two shifts during the night, using their sleep break for prayer, reflection or reading by candlelight.¹

Artificial light permanently changed the way we live, in many ways for the better. But there has been a second change since the invention of artificial light that might be more consequential: the proliferation of electronic devices that create "blue light." To that end, 96 percent of Americans now own cellphones, mostly smartphones, and 75% own desktop or laptop computers. About 50% own tablets and e-readers.²

Blue light rays are the shortest wavelengths of light and constitute one-third of all the sunlight we see.³ But smartphones, computers, tablets, e-readers, TVs and LED (light-emitting diode) and CFL (compact fluorescent lamp) lighting also emit blue light and have significantly added to the amount of blue light we now receive.⁴

There are many well-documented risks associated with exposure to blue light from these electronic devices, one being impaired sleep. As such, we’re advised to tone down or completely avoid blue light at night. Interestingly, researchers at Manchester University discovered that blue light associated with twilight actually helped mice sleep better — opposite of current thinking on blue light’s effect on sleep.⁵

It was a single study using small groups of mice (seven to eight mice in an average group) but if the same proves true for humans, it could change everything we know about using blue light at night, lead researcher Tim Brown told BBC:⁶

“During the daytime, the light that reaches us is relatively white or yellow and has a strong effect on the body clock and around twilight, once the Sun sets, the bluer the light becomes," he said. "So if you want to avoid light having a strong effect on your body clock, dim and blue would be the way to go …

"At the moment, often what people are doing is adjusting the colour of lighting or visual displays and making the screens more yellow. Our prediction is that changing the colour is having exactly the wrong effect. It's counteracting any benefit that you might get from also reducing the brightness of the screen."

In other words, blue lights may actually induce sleep, rather than impair it. Moreover, the yellow and orange lights with which many people have sought to replace blue lights, especially at night, may actually be the light waves that disrupt and harm sleep.

But before we run off and change the rule books on the topic, at least one scientist says not so fast. For one thing, mice are nocturnal; they’re naturally active at night, while humans are typically sleeping. Blue light helping mice sleep doesn’t necessarily make it true for humans, says Manuel Spitschan, Ph.D., a research fellow with an interest in visual and nonvisual responses to light in humans.

“This is fascinating work, but we really don’t know yet that the same happens in humans,” Spitschan told BBC. “That’s the difficulty with animal work. It should be possible to do tests with people in the future to find out for sure.”

Study Questions a Well-Accepted Hypothesis

Search for "blue light" on the internet and you will find hundreds of health and medical sites that warn you about the harmful effects of blue light on your sleep. Here is what the National Sleep Foundation says:⁷

"The reason that blue light is so problematic is that it has a short wavelength that affects levels of melatonin more than any other wavelength does.

Light from fluorescent bulbs and LED lights can produce the same effect. Normally, the pineal gland in the brain begins to release melatonin a couple of hours before bedtime, and melatonin reaches its peak in the middle of the night.

When people read on a blue light-emitting device (like a tablet, rather than from a printed book) in the evening, it takes them longer to fall asleep; plus, they tend to have less REM sleep (when dreams occur) and wake up feeling sleepier— even after eight hours of shuteye."

I have often warned about the effect of blue light on sleep and recommended "blue blocker" glasses to protect your eyes at night. So, if this new research, published in the journal Current Biology,⁸ is true, it could have far-reaching repercussions on how humans approach the use of blue light at night in the future.

Brown explained the new thinking and the role of melanopsin, a photo pigment expressed in retinal ganglion cells, in light-affected sleep, this way:⁹

"We show the common view that blue light has the strongest effect on the clock is misguided; in fact, the blue colours that are associated with twilight have a weaker effect than white or yellow light of equivalent brightness.

There is lots of interest in altering the impact of light on the clock by adjusting the brightness signals detected by melanopsin but current approaches usually do this by changing the ratio of short and long wavelength light; this provides a small difference in brightness at the expense of perceptible changes in colour.

… We argue that this is not the best approach, since the changes in colour may oppose any benefits obtained from reducing the brightness signals detected by melanopsin. Our findings suggest that using dim, cooler, lights in the evening and bright warmer lights in the day may be more beneficial."

General Sleep Advice Is Still Valid

In the meantime, whether blue light proves to be further implicated in insomnia in humans or not, there are still reasons to disengage from your electronic devices before bedtime — and yellow light is not the answer. Christian Benedict, associate professor at the department of neuroscience at Uppsala University and author of a 2016 study published in the journal Sleep,¹² told Consumer Affairs:¹³

"'It must however be kept in mind that utilizing electronic devices for the sake of checking your work e-mails or social network accounts before snoozing may lead to sleep disturbances as a result of emotional arousal."

Benedict’s study suggests receiving daytime bright light exposure, a practice that I encourage, can help offset sleep disturbances caused by exposure to electronic devices at night. Here are some additional important suggestions for a good night's sleep, regardless of where the blue light controversy ends.

Sleep in complete darkness — Even the tiniest bit of light in the room, such as that from a clock radio LCD screen, can disrupt your internal clock and your production of melatonin and serotonin, thereby interfering with your sleep (and raising your risk of cancer).

Keep the temperature in your bedroom no higher than 70 degrees F — Studies show the optimal room temperature for sleep is between 60 and 68 degrees F. Keeping your room cooler or hotter can lead to restless sleep. When you sleep, your body's internal temperature drops to its lowest level, generally about four hours after you fall asleep.

Eliminate electric and electromagnetic fields (EMFs) in your bedroom — These can disrupt your pineal gland's production of melatonin and serotonin, and are a significant contributor to mitochondrial damage and dysfunction, which is at the heart of virtually all chronic disease.

Move alarm clocks and other electrical devices away from your bed, and avoid using loud alarm clocks — If you need to use these devices, keep them as far away from your bed as possible, preferably at least 3 feet. Keep your cellphone as far away from your bedroom as possible if you feel it must be on, or put it in airplane mode. Better yet, if you keep it in your bedroom, shut it down.

Adopt a neutral sleeping position — If you're a side- or stomach sleeper and find yourself frequently tossing and turning at night and/or waking up with aches and pains, your sleeping position may be a primary culprit.

Reserve your bed for sleeping — If you are used to watching TV or doing work in bed, you may find it harder to relax and drift off to sleep, so avoid doing these activities in bed.

Consider separate bedrooms — Studies suggest that, for many people, sharing a bed with a partner can significantly impair sleep, especially if the partner is a restless sleeper or snores. If bedfellows are consistently interfering with your sleep, you may want to consider a separate bedroom. You may also need to banish your pets from the room if their presence impairs your sleep.

Beware of Quick-Fix Sleeping Medications

Regardless of what additional research about blue light might reveal, it’s certainly true that more Americans than ever suffer from poor sleep and insomnia. Most reasons stem from an urban, "workaholic" lifestyle that encourages people to squeeze sleep in between their other busy activities, rather than make restorative sleep a top health priority.

Sadly, drug makers have tried to cash in on Americans' sleep problems by aggressively advertising sleeping pills and other types of sedatives even though they are likely to make the situation worse. For example, in 2013, the Journal of Hospital Medicine reported a strong association between the popular sleeping pill Ambien (zolpidem) and falls.¹⁴

More Sleep Medication Dangers

Just as dangerous as falls, "complex sleep behaviors" such as sleepwalking, sleep driving and using a stove while not fully awake, which pose the "risk of serious injury and death," are associated with three popular sleeping pills (eszopiclone, zaleplon and zolpidem), says the FDA.¹⁵ Warnings about such behaviors were already on the drug labels, and strengthened, in April of 2019.

Nevertheless, seeing the great profit in sleep medications, drug makers have rolled out a host of particularized sleep disorders: chronic, acute, transient, initial and middle-of-the-night insomnia, early-morning wakening disorder and non-restful sleep disorder — all of which they claim require specific medications.

The irony is that almost all insomnia and poor sleep can be treated with a healthier lifestyle and sleep hygiene. Moreover, when people try to stop taking sleep medications, they often experience rebound effects and their sleep may become worse, not better, from the drugs.

Adding to the problems, drug makers have also discovered the profit in drugs that treat "excessive sleepiness" and more obscure sleep conditions such as non-24-hour sleep-wake disorder, shift work sleep disorder and narcolepsy. These conditions and the drugs that treat them are now aggressively advertised, a strategy that grows awareness of the so-called conditions, as well as the pool of potential patients.

Since most drugs for these conditions stimulate the body, they likely can cause more sleep problems and lead to more drugs. Is it any surprise, then, that sleeping problems are getting worse, not better, in the U.S.?

Needless to say, coffee and cigarettes also make sleep problems worse. Alcohol can help you fall asleep faster, but it makes sleep more fragmented and less restorative. If you want more information on how to achieve better sleep, don't forget to refer to my "33 Secrets to a Good Night's Sleep."

The Take-Home Message on Blue Light

Studies have linked blue light with many serious effects, including:

Macular degeneration¹⁶	Shortened lifespan¹⁷
Insulin resistance and metabolic disorders	Myopia and eye strain
Mitochondrial dysfunction	Cancer

So, until actual human studies are done and research on blue light shows similar results to the mouse study, the best thing to do is avoid it and try natural ways to work with your own circadian rhythm, using sleep strategies that we know will work.

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