Thursday, May 31, 2012

Will Dark Chocolate a Day Keep the Doctor Away?

Study: Dark Chocolate May Lower Heart Disease and Stroke Risks

Reviewed by Laura J. Martin, MD

dark chocolate
May 31, 2012 -- Should people at high risk of heart attack and strokeeat dark chocolate every day?
Maybe, according to a new study from Australia.
"Dark chocolate may be a pleasant and effective way of delivering important dietary components that can provide health benefits to the ever increasing numbers of people at increased risk of cardiovascular disease," says researcher Christopher M. Reid, PhD, professor of cardiovascular epidemiology and preventive medicine at Monash University in Australia.
Reid and his team constructed a mathematical model to predict the long-term health effects of eating dark chocolate daily in high-risk people. They did not study actual people eating actual chocolate.
The researchers also computed whether it would be cost-effective to spend money on a public education campaign about dark chocolate's benefits. They found it would be.
Several studies have found that dark chocolate, with its heart-healthy flavonols, can lower blood pressure and improve cholesterol.
However, Reid believes theirs is the first study to model the long-term effects of eating dark chocolate in reducing cardiovascular risk.
The study is published in the journal BMJ.

Chocolate to Prevent Heart Attacks

Reid's team first looked at the treatment effects linked with dark chocolate by evaluating studies already published.
They computed the number of heart attacks and strokes that would occur with and without the dark chocolate.
They also looked at 2,013 people from the Australian Diabetes, Obesity, and Lifestyle study. All had metabolic syndrome but none had diagnosed heart disease or diabetes at the start.
Metabolic syndrome increases the risk of heart disease and stroke. It is diagnosed when three or more of the following factors are present: high blood pressure, high triglycerides, low levels of "good" HDL cholesterol, high blood sugar, or a large waist size.
Reid's team looked at costs associated with the heart and stroke problems.
They used these cost figures to determine how much money could be spent each year to educate high-risk people about dark chocolate and still be cost-effective.
Their study looked longer-term than most, 10 years, Reid says.

Dark Chocolate to Prevent Heart Disease, Stroke

First, the researchers plugged in the best-case scenario: 100% of the people eating the recommended 100 grams of dark chocolate (3.5 ounces, or about two bars) a day for 10 years.
This would prevent 70 nonfatal and 15 fatal heart attacks and strokes per 10,000 people over 10 years, according to the study model.
With an 80% adherence rate, there would be 55 fewer nonfatal and 10 fewer fatal heart attacks and strokes per 10,000 people over 10 years.
The estimates may be low, Reid says.
They found that it would be cost-effective to spend $42 per person per year on education.
The education might include advertising, educational campaigns, or subsidies to pay for the chocolate, Reid says.

Other Experts Not Convinced

The new model drew mixed reactions from U.S. chocolate researchers.
"It's over-assuming the benefits," says Eric Ding, PhD, nutritionist and epidemiologist at Harvard Medical School. He reviewed the findings.
"They are basing their estimates on heart disease intermediate risk factors (blood pressure and cholesterol) and not on actual heart disease events, like heart attacks," Ding tells WebMD.
The researchers are ignoring some downsides, he says. "They are ignoring the dangers of too many calories and too much fat and sugar from the chocolate bar," he says.
Those at risk of heart attack and stroke should first focus on lifestyle, Ding says. That includes weight loss if needed, exercising regularly, and not smoking.
Joe Vinson, PhD, professor of chemistry at the University of Scranton and a long-time chocolate researcher, likes the study, even though it has limitations.
"It's all theoretical based on statistics," he says. Even so, he says, "It's wonderful news again on the health effects of dark chocolate for people who have a little higher risk [of heart problems] than the normal person."
With their doctor's approval, people at risk of heart attacks or strokes could eat a bit of dark chocolate daily and monitor their weight and blood pressure, Vinson suggests.
He recommends eating less than 100 grams used in the model. He suggests about 40 grams, or about one chocolate bar, daily.
Reid suggests that the chocolate should be dark and at least 60%-70% cocoa.
The research was supported by an Australian Research Council grant with Sanofi-Aventis Australia.

Sharp Hits Solar Cell Efficiency Record of 43.5%


© Sharp
With all of the different types of solar cells being developed from thin-film tocrystalline silicon as well as new ways of boosting light absorption it seems there is always a new solar cell efficiency record being announced, but this new record from Sharp of 43.5% is a pretty big deal. A large jump over the company's previous record of 36.9% efficiency in November 2011, it shows that solar technology is getting ever closer to that 50% mark that could revolutionize the industry.
Sharp achieved the conversion efficiency record with their concentrator triple-junction compound solar cell that uses a lens-based system to focus sunlight on the cells to generate electricity.
According to Sharp:
Compound solar cells utilize photo-absorption layers made from compounds consisting of two or more elements, such as indium and gallium. The basic structure of this latest triple-junction compound solar cell uses Sharp’s proprietary technology that enables efficient stacking of the three photo-absorption layers, with InGaAs (indium gallium arsenide) as the bottom layer.
To achieve this latest increase in conversion efficiency, Sharp capitalized on the ability of this cell to efficiently convert sunlight collected via three photo-absorption layers into electricity. Sharp also optimized the spacing between electrodes on the surface of the concentrator cell and minimized the cell’s electrical resistance.

© Sharp
Conventional solar panels that are on the market now still have an efficiency of only about 15 to 20 percent, but these breakthroughs made in labs will eventually lead to climbing efficiencies in mass market solar panels too. Sharp's compound solar cell technology is currently only used in space satellites, but the company wants to adapt the technology into small-surface-area solar cells that would be practical for use down here on the ground.
The conversion efficiency record was confirmed by the Fraunhofer Institute for Solar Energy in April 2012 and it is the same exact conversion efficiency achieved by Solar Junction of the United States in March 2011. The fact that two companies have been able to achieve the same high efficiency is a good sign that the industry is quickly scaling up efficiency across the board.

Wednesday, May 30, 2012

 Pictureque carving dressing the entrey to the Roseville School of Arts.
Posted by Picasa

Sunday, May 27, 2012

Brain Development

Disclaimer

There is a great deal of technology building up that guides practitioners in addressing childhood learning matters. Those of us laymen wishing to express an opinion on the subject need to be sure that our statements do not bring the technicians or practitioners into disrepute. Still, laymen are entitled to an opinion… so having disclosed my ignorance in the matter, let me tell you a thing or two.

Equal Starting Points

It is my belief that newborn babes have pretty-well the identical number of neurons. We all have the potential to build our allocated quotient of 100-150 trillion synapses. Arguably, heredity gives one child the propensity to build synapses in parts of the brain where forbears had well-worked skills. Arguably, some infants develop synapses at different rates; perhaps girls build theirs a little faster than boys; perhaps first-born build theirs faster because of the additional attention from parents. 
Arguably, the IQ (intelligence Quotas) tests in schools mislabelled (or misunderstood) aspects of intelligence. Does a child able to more quickly recognise a pattern have a higher intelligence than a child able to build a particular pattern? Is it nurture or nature that determines the allocation of synapses across the brain and across different types of skills? 

Academic studies give great preference to having an abundance of synapses in the skills associated with verbalising, numeracy, logic and memory. Historically, we have believed that some kids will never be capable of learning calculus, some kids will never be able to draw; some kids will never be able to run a 12-second 100 metres.  I keep an eye out for studies that claim to be able to accurately predict the boundaries of learning for each individual. If I’ve missed these articles, perhaps someone can point them out for me. 


Sugars and the Juvenile Brain

Every parent and grandparent will have observed a sensible focussed child drink a sugary cordial and within 5 minutes become an uncontrollable zombie. Each of us may have experience lack of brain stimulus (feeling bored, lethargic, uninterested) only to become an energised genius 5-minutes after our morning cup of coffee. This immediate change in brain functioning should be able to tell us a lot about the functioning of this critical organ.

Researchers are now paying greater attention to the longer-term effects of sugar on our brain function. Should we feed our kids food with high fructose contents? Should school canteens be pedalling soft drinks overloaded with sugar? (Perhaps ACCC should look at the appropriate use of the word ‘soft’ in this branding exercise.) Perhaps a more responsible approach could be to offer drinks only with coffee additives… with no sugar. 


The Teen Issue

Some researchers are forming the view that during middle to late adolescence, the teenage body clock takes a nocturnal shift. These researchers claim the propensity to sleep later and stay-up later affects all adolescents… those who have a propensity to get up early will modify their waking hours by about the same degree as those who have always had a propensity to get up late. Researchers have yet to suggest a biological or evolutionary explanation of this shift. However, the researchers claim it is useless to ignore the phenomenon… adolescent students will learn more slowly in classes that start early in the day. Arguably, their driving licenses should be restricted to driving only after 10:00AM each morning. Perhaps, parents should schedule their heart-to-heart talks with their adolescent children after 10:00PM… when they can be more likely to have their child’s full attention.

There appears to be an existing trend for schools to schedule the start of Junior high-school classes earlier in the day and schedule senior secondary school classes to start late in the day. 

Regulated Rate of Learning 

We have all suffered the stress of choosing whether to push our child to keep up with the class average in all subjects, against the view that all kids will welcome the learning experience in all skills if you just wait long enough. How hard… how early… that’s the question. Some parents argue that a very important gift to give a child is to allow them the time to grow. Let them spend their free time in unstructured distraction. If the wandering child comes across a topic that catches his/her interest, give them encouragement to follow-up. This theory assumes that sooner or later, each child will want to learn within the parameters that have caught his/her interest. 

This theory cites Einstein being unable to walk or properly talk up to the age of 3. It points to the low proportion of successful entrepreneurs with tertiary education. Bill Gates dropped out, as did Steve Jobs and Mark Zuckerberg. They point to the high rate of depression within professional academics. All good points. However, it takes nerves of steel to see your child/grandchild falling behind class in basic skills… be it reading or writing or arithmetic… and not apply some pressure to get the child to allocate more effort to learning. It gets down to basic philosophic points regarding happiness verses wealth verses contributing to society.


Learning through Different Channels

One last matter. Some kids learn through association. Some kids learn best through repetitious memorising. Some kids learn best through tactile handling objects. You may be one of those people who can remember every word of Bob Dylan’s songs but can’t remember the name of the Prime Minister in the 1970’s. 

It seems that the neurons used in singing are quite distant from the neurons used for memorising facts. Some educators encourage children having difficulty in memorising spelling lists (for example) to put the words into a song to encourage them to see the word when they sing the appropriate part of the song. The world champions in memorising lists (e.g. the sequence of playing cards in a shuffled pack) have somehow trained their mind to associate each item with a real-world object. The player memorises the objects that somehow triggers the name of the list item… beats me!

It would be great if researchers could explain how ‘ordinary people’ can use these memorising techniques, particularly school children… who currently spend inordinate amounts of times memorising lists that will not be particularly useful in later life.

The Rant is Over

Well, like any good rant, I have thrown opinions at you without any purpose and without any suggested solution. In conclusion, it shows how much more we have to learn regarding the workings (or non-workings) of our brains.

Saturday, May 26, 2012

Old and New Neurons Trade Roles to Aid Memory

Brain cells help us recall the past by taking on new roles as they age

neurons, new tricks, memory,
For decades researchers have known that our ability to remember everyday experiences depends on a slender belt of brain tissue called the hippocampus. Basic memory functions, such as forming new memories and recalling old ones, were thought to be performed along this belt by different sets of neurons. Now findings suggest that the same neurons in fact perform both these very different functions, changing from one role to another as they age.

Image: Illustration by Thomas Fuchs



The vast majority of these hippocampal neurons, called granule cells, develop when we are very young and remain in place throughout our lives. But about 5 percent develop in adulthood through the birth of new neurons, a process known as neurogenesis. Young granule cells help form new memories, but as they get older they switch roles to helping recall the past. Newer granule cells pick up the slack, taking on the role of helping to form new memories. Susumu Tonegawa of the Massachusetts Institute of Technology and his colleagues published the findings on March 30 in the journal Cell.
Tonegawa’s team tested the role of these adult-born cells by genetically engineering mice in which the old cells could be selectively turned off. They then put the mice through a series of mazes and fear-conditioning tests, which demonstrated that young granule cells are essential to forming separate memories of similar events, whereas old granule cells are essential to recalling past events based on small cues. This discovery suggests that memory impairments common in aging and in post-traumaticstress disorder may be connected to an imbalance of old and new cells. “If you don’t have a normal amount of young cells, you may have a problem distinguishing between two events that would be seen as different by healthy people,” Tonegawa says. At the same time, the presence of too many old cells would make it easier to recall traumatic past experiences based on current cues.
Previous research has shown that both traumatic experiences and natural aging can lead to fewer new neurons being produced in the hippocampus. But a cause-and-effect relation between impaired neurogenesis and memory disorders has yet to be established. If such a connection is found, this research will have opened the door to a novel class of treatments aimed at stimulating neurogenesis. Already it is changing the way we think memory works.
This article was published in print as "Old Neurons, New Tricks"

Thursday, May 24, 2012

Drinking Red Wine Is Good for Gut Bacteria

Moderate Intake of Some Red Wines May Improve Health, Study Shows
By Cari Nierenberg
WebMD Health News
Reviewed by Louise Chang, MD

red wine pouring into glass
May 25, 2012 -- Drinking a daily glass of red wine not only tastes good to many people, but it's also good for the bacteria lining your large intestine.
A new Spanish study suggests that sipping about 9 ounces of Merlot or a low-alcohol red wine changed the mix of good and bad bacteria typically found in the colon in ways that can benefit your health.
Bacteria may sound like a bad thing to have in your intestinal tract, but having a balanced mix of them actually helps to digest food, regulate immune function, and produce vitamin K (which plays a key role in helping the blood clot).
Since the study results showed that Merlot and low-alcohol red wine had similar positive effects on intestinal bacteria, researchers suspect it's not due to the alcohol but to the polyphenol compounds found in the wine.
Polyphenols are helpful plant-based compounds found in a variety of foods and beverages. Besides red grapes, many other fruits and vegetables are rich sources of polyphenols, as are coffee, tea, chocolate, and some nuts.
Previous research has looked at whether polyphenols in the diet can influence the balance of intestinal bacteria. This study sought to explore whether drinking red wine can have a similar prebiotic effect. Prebiotics are substances you eat that help promote the growth of good gut bacteria.

Red, Red Wine

In this small study, which appears in the American Journal of Clinical Nutrition, researchers followed 10 healthy middle-aged men. For the first 15 days of the study, the men had no wine or other alcohol. This was followed by three 20-day periods in which the men were given one of three beverages to drink each day: They received either 9 ounces of Merlot, 9 ounces of low-alcohol-content red wine, or about 3 ounces of gin.
Unlike the red wines, gin contains no polyphenols, so it served as a comparison.
Throughout the study, volunteers were asked not to change their diets or exercisehabits. They were also told not to drink any additional alcohol. Blood, urine, and stool samples were collected from each man during all four study periods. And their weights and blood pressures were monitored.
The findings showed that the balance of intestinal bacteria shifted in the men in a similar way whether they drank the Merlot or low-alcohol red wine. In both cases, they had a larger percent of certain beneficial gut bacteria.
After drinking the polyphenol-rich beverages, the men also had lower blood pressure. It also decreased triglyceride levels, HDL cholesterol (the so-called goodcholesterol), and C-reactive protein (CRP) levels, a measure of inflammation.
"This study was the first to show that regular, moderate consumption of red wine could have a noteworthy effect on the growth of select gut microbiota," the researchers conclude.

Sunday, May 20, 2012

When Should Schools Start in the morning?



I am glad to see that there is more and more interest in and awareness of sleep research. Just watch Sanjay Gupta on CNN or listen to the recent segment on Weekend America on NPR.

At the same time, I am often alarmed at the levels of ignorance still rampant in the general population, and even more the negative social connotationsof sleep as an indicator of laziness.
Nothing pains me more than when I see educators (in comments) revealing such biases in regards to their student in the adolescent years. Why do teachers think that their charges are lazy, irresponsible bums, and persist in such belief even when confronted with clear scientific data demonstrating that sleep phase in adolescents is markedly delayed in comparison to younger and older people?
In short, presumably under the influence of the sudden surge of sex steroid hormones (and my own research gently touched on this), the circadian clock phase-advances in teen years. It persists in this state until one is almost 30 years old. After that, it settles into its adult pattern. Of course, we are talking about human populations, not individuals – you can surely give me an anecdote about someone who does not follow this pattern. That’s fine. Of course there are exceptions, as there is vast genetic (and thus phenotypic) variation in human populations. This does not in any way diminish the findings of population studies.
Everyone, from little children, through teens and young adults to elderly, belongs to one of the ‘chronotypes’. You can be a more or less extreme lark (phase-advanced, tend to wake up and fall asleep early), a more or less extreme owl (phase-delayed, tend to wake up and fall asleep late). You can be something in between – some kind of “median” (I don’t want to call this normal, because the whole spectrum is normal) chronotype.
Along a different continuum, one can be very rigid (usually the extreme larks find it really difficult to adjust to work schedules that do not fit their clocks), or quite flexible (people who find it easy to work night-shifts or rotating shifts and tend to remain in such jobs long after their colleagues with less flexible clocks have quit).
No matter where you are on these continua, once you hit puberty your clock will phase-delay. If you were an owl to begin with, you will become a more extreme owl for about a dozen years. If you are an extreme lark, you’ll be a less extreme lark. In the late 20s, your clock will gradually go back to your baseline chronotype and retain it for the rest of your life.
The important thing to remember is that chronotypes are not social constructs (although work-hours and school-hours are). No amount of bribing or threatening can make an adolescent fall asleep early. Don’t blame video games or TV. Even if you take all of these away (and you should that late at night, and replace them with books) and switch off the lights, the poor teen will toss and turn and not fall asleep until midnight or later, thus getting only about 4-6 hours of sleep until it is time to get up and go to school again.
More and more school districts around the country, especially in more enlightened and progressive areas, are heeding the science and making a rational decision to follow the science and adjust the school-start times accordingly. Instead of forcing teenagers to wake up at their biological midnight (circa 6am) to go to school, where invariably they sleep through the first two morning classes, more and more schools are adopting the reverse busing schedule: elementary schools first (around 7:50am), middle schools next (around 8:20am) and high schools last (around 8:50am). I hope all schools around the country eventually adopt this schedule and quit torturing the teens and then blaming the teens for sleeping in class and making bad grades.
No matter how much you may wish to think that everything in human behavior originates in culture, biology will trump you every now and then, and then you should better pay attention, especially if the life, health, happiness and educational quality of other people depends on your decisions.
======
Recently, Lance Mannion wrote an interesting post on the topic, which reminded me also of an older post by Ezra Klein in which the commenters voiced all the usual arguments heard in this debate.
There are a couple of more details that I have not touched upon in the previous posts.
First, lack of sleep can lead to obesity and even diabetes, as the circadian clock is tightly connected to the ghrelin/leptin system of hormonal control of hunger, feeding and fat-deposition.
Second, lack of sleep discourages exercise. Put these two pieces of data together, and you get a national epidemic of obesity, not just a bunch of sleep-deprived children.
Third, lack of sleep has a well-documented effect on mood. No, teenagers are not naturally that moody – at least not all of them. They are just barely “functional” (instead of “optimal”) and walk through life like zombies because they are operating on 4-8 hours of sleep instead of 9 hours (optimal for teens, it goes down to about 8 for adults). Of course they are moody.
Fourth, chronic sleep deprivation can have long-term consequences, ranging frompsychiatric diseases to cancer. Remember that teens in high-school (and college students are faring worse!) are constantly jet-lagged!
There is even a hypothesis floating around that sleep-delay in adolescence may affect the onset of picking up smoking.
Fifth – and I did not think of this although it is obvious – teenagers above a certain age, still in high school, are allowed to drive. If they are driving themselves to school at 6 or 7am, when their circadian clocks think is it 3 or 4am, it is as if they are driving drunk. There is actually a scale devised by one of the sleep researchers that tells which time of the night corresponds to what number of bottles of beer. Driving at 4am (or driving a ship, like Exxon Valdez, or operating a power-plant, like one in Chernobyl) is the equivalent of driving drunk – way over the legal limits. Teenagers driving at 7am are equally “drunk”.
One of the reasons for the resistance to healthy initiatives to change school-start schedules stems from the fact that the world is organized by adults and adults want to have the world run according to schedules that fit their moods and are unwilling to change it – they may not know that teens feel differently, or they defend their preferences nonetheless.
A large proportion of adults in this country still subscribe to barbaric notions that sleep is a shameful activity, a sign of laziness, and that teens need to be tortured in order to “steel” them to grow into “real men”. This has roots all the way back to the Puritan so-called “work-ethic” which is really a “no fun for anyone” punitive ethic long ago shown to be physically and emotionally debilitating.
When I was a kid, back in old now-non-existent Yugoslavia, most schools in big urban areas worked in two shifts. All the kids started school at 8am and ended at 1:15pm for one week, then started at 2pm and ended at 7:15pm the next week, and so on…
If a school had, let’s say, twelve classes of the seventh grade, six of those would be in the A-shift and the other six in the B-shift. Each shift had its own complete set of teachers, assistants, nurses…everything except the one shared Principal and the school psychologist.
The time between 1:15pm and 2pm was for supplementary classes (either for those who needed extra help, or for those preparing for Math Olympics and such) and clubs. That was also time for kids from two shifts to meet and get to know each other (it is amazing how many kids from opposite shifts started dating each other after the year-end Big Trip to the Coast). There was no such thing as the American hype for high-school competitive sports, which I still find strange and curious after 15 [now 20] years in this country.
Thus, you get to sleep in for a week (but miss out on afternoon activities), then have to get up relatively early for a week but have the afternoon free to gallivant around town. Nobody there understands what’s the American fuss over kids being home alone – of course they are home alone, cleaning the house, fixing meals, doing homework and BETTER be getting to school on time!
Teachers were pretty understanding about sleeping types. I do not recall ever having a big test, quiz or exam being given at the extremes of the day (around 8am or around 7pm). As an owl myself, I was much more likely to raise my hand, participate in discussions, or volunteer for oral examinations during the week when I was in school in the afternoon, and that was fine with most of my teachers.
Transportation was not an issue. Most kids lived close enough to their neighborhood school to walk. For those who lived a little farther away – hey, no problem, that’s Europe, so Belgrade has a huge and pretty efficient public transportation system. I do not remember ever seeing any of my friends ever being dropped off to school by a parent driving a car! Or being brought to or picked up from school by a parent beyond fourth grade at all – period. And the minimum driving age being 18, nobody drove themselves to school either.
In rural areas, there was no need for two shifts – something like 9am-2:15pm was good enough to accommodate all of the kids.
I do not think that this kind of system can be implemented in the USA. It relies on an efficient public transportation which, with exception of a few oldest East Coast cities, is practically non-existent. American cities have been built for cars.
But some things can be done.
First, swap the starting times so elementary kids go to school first, middle school next and high school last (e.g., around 8am, 8:30am and 9am respectively). Studies show that teens do not go to sleep later if their school starts later. Some cynics claim that is what teens will do. But they do not. Actually, they fall asleep at the same time, thus gaining an additional hour of sleep.
Teens are almost adults. The current generation of teens, perhaps because of a closer and tighter contact with their parents than any generation before, is the most serious, mature and responsible generation I have seen. Give them a benefit of the doubt. Just because you were into mischief and hated your parents when you were their age does not mean that today’s kids are the same.
Second, start the school day – for all kids every day – with PE (or some kind of exercise), preferably outdoors, as both exposure to daylight and the exercise have been shown to aid in phase-shifting the circadian clock.
Third, let them eat breakfast afterwards (sticking to a meal schedule also helps entrain the clock). Follow up with the electives which kids may be most interested in.
By the time they hit math, science and English classes around 11 or so, their bodies are finally fully awake and they can understand what the teacher is saying, and do the tests with a clear mind instead of in a sleepy haze.
Do not permit any caffeine to be sold in schools. Advise parents not to allow TV or any other electronics to be in kids’ bedrooms. Let them enjoy those activities in the living room. Bedroom is for sleeping, and sleeping alone. A book before bed is fine, but screens just keep them awake even longer.
Finally, rethink all those extra activities you are forcing the teens to do: sports, art, music, etc. In teen’s minds, the day does not start with the beginning of school in the morning. We may think that we are at work most of our day. Teens do not – they consider their day to begin at the time school-day is over. Their day begins in the afternoon. School is something they have to deal with before they can have their day. Realize this and give them time and space to do with their day what they want. Do not push them to do things that you think they’ll need to get into Harvard. Let them be – leave them alone. Then they’ll go to sleep at a normal time.
Concern for our kids’ physical and mental health HAS to trump all other concerns, including economic costs, cultural traditions and adult preferences. We have a problem and we need to do something, informed by science, to fix the problem. Blaming the messenger, proposing to do nothing, and, the worst, blaming the kids, is unacceptable.
===============
All of this targets high-schoolers. However, there is barely any mention of college students who are, chronobiologically, in the same age-group as high-school students, i.e., their sleep cycles are phase-delayed compared to both little kids and to adults.
In a way, this may be because there is not much adults can do about college students. They are supposedly adults themselves and capable of taking care of themselves. Nobody forces (at least in theory) them to take 8am classes. Nobody forces them to spend nights partying either.
They are on their own, away from their parents’ direct supervision, so nobody can tell them to remove TVs and electronic games out of their bedrooms. The college administrators cannot deal with this because it is an invasion of students’ privacy.
Forward-looking school systems in reality-based communities around the country have, over the last several years, implemented a policy that is based on science – sending elementary school kids to school first in the morning, middle-schoolers next, and high-schoolers last. This is based on the effects of puberty on the performance of the human circadian clock.
For teenagers, 6am is practically midnight – their bodies have barely begun to sleep. Although there have been some irrational (or on-the-surface-economics-based) voices of opposition – based on outdated notions of laziness – they were not reasonable enough, especially not in comparison to the scientific and medical information at hand, for school boards to reject these changes.
I am very happy that my kids are going to school in such an enlightened environment, and I am also happy to note that every year more school systems adopt the reasonable starting schedules based on current scientific knowledge.
Yet, college students are, from what I heard, in much worse shape than high-schoolers. Both groups should sleep around 9 hours per day (adults over thirty are good with about 8 hours). High-schoolers get on average 6.9 hours. College students are down to about five! The continuous insomnia of college students even has its own name in chronobiology: Student Lag (like jet-lag without travelling to cool places). Is there anything we, as a society, can do to alleviate student lag? Should we?
===============
This kind of ignorant bleating makes me froth at the mouth every time – I guess it is because this is my own blogging “turf”.
One of the recurring themes of my blog is the disdain I have for people who equate sleep with laziness out of their Puritan core of understanding of the world, their “work ethic” which is a smokescreen for power-play, their vicious disrespect for everyone who is not like them, and the nasty feeling of superiority they have towards the teenagers just because they are older, bigger, stronger and more powerful than the kids. Not to forget the idiotic notions that kids need to be “hardened”, or that, just because they managed to survive some hardships when they were teens, all the future generations have to be sentenced to the same types of hardships, just to make it even. This is bullying behavior, and disregarding and/or twisting science in the search for personal triumphalism irks me to no end.
I hated getting up early, too. I still hate it, and I’m so far beyond growth hormones that I don’t even remember how they felt. But I do remember that in middle and high school, I dragged myself out of the house at 5 a.m. every day of the week to deliver papers before I caught the 6:45 a.m. bus to school. I never fell asleep in class. Neither did anybody else. And something caused me to grow 6 inches and add 35 pounds between sophomore and junior year. At the end of that kind of day, complete with cross-country, basketball or track, I had no trouble falling asleep at 10 p.m.
He said that he grew up in height and weight when he was in high school. Who knows how much more he would have grown if he was not so sleep deprived (if his self-congatulatory stories are to be believed and he did not slack off every chance he had). Perhaps he would not grow up to be so grouchy and mean-spirited if he had a more normal adolescence.
I don’t know where he got the idea that growth hormone is a cause of the phase-delay of circadian rhythms in adolescence. It could be, but it is unlikely – we just don’t know yet. But, if a hormone is a cause, than it is much more likely to be sex steroids. Perhaps his sleep-deprived and testosterone-deprived youth turned him into a sissy with male anxiety he channels into lashing at those weaker than him?
In previous centuries, adolescents in an agrarian society got up at 4:30 or 5a.m. with their parents to milk the cows or do any other of a long list of chores. Did growth hormones pass them by? Where were the “studies” that showed they really needed to go to bed after midnight and sleep until 10? And why weren’t their parents all being reported to the DSS? Oh, that’s right, there was no DSS. How did that generation survive?
He assumes that in times before electricity, teenagers used to wake up and fall asleep at the same time adults did. Well, they did not. Studies of sleep patterns in primitive tribes show that adolescents are the last ones to wake up (and nobody bashes them for it – it is the New Primitives with access to the media that do that) and the last ones to fall asleep – they serve as first-shift sentries during the night watch.
Even in this, the 21st century, kids who enter the military at 17 find that they can fall asleep easily at 9:30 or 10, because they know they’re going to be getting up at 4:30 or 5. Apparently the Army hasn’t read the study on circadian rhythms.
Actually, the military being the most worried by this problem is funding a lot of research on circadian rhythms and sleep and has been for decades. Because they know, first hand, how big a problem it is and that yelling sargeants do not alert soldiers make.
Kids, if you need more sleep, my study shows there’s a simple way to get it. Turn off – I mean “power down” – the cell phone, the iPod and the computer sometime before 11 p.m. Turn off the TV. Turn off the light. Lie down in bed and close your eyes.
…and sit in the dark for the next four hours, heh?
What especially drives me crazy is that so many teachers, people who work with adolescents every day, succumb to this indulgence in personal power over the children. It is easier to get into a self-righteous ‘high’ than to study the science and do something about the problem. It is easier to blame the kids than to admit personal impotence and try to do something about it by studying the issue.
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My regular readers are probably aware that the topic of adolescent sleep and the issue of starting times of schools are some of my favourite subjects for a variety of reasons: I am a chronobiologist, I am an extreme “owl” (hence the name of this blog), I am a parent of developing extreme “owls”, I have a particular distaste for Puritanical equation of sleep with laziness which always raises its ugly head in discussions of adolescent sleep, and much of my own past research was somewhat related to this topic.
So, I was particularly pleased when Jessica of the excellent Bee Policy blog informed me of the recent publication of a book devoted entirely to this topic. Snooze…or Lose!by Helen Emsellem was published by National Academies and Jessica managed to get me an advanced reading copy to review.
You can also read the book online (or buy the PDF). Much more information on the topic can be found on the book webpage, on the National Slep Foundation website, onDr.Emsellem’s homepage and the Start Later for Excellence in Education Proposal (S.L.E.E.P.) website. I strongly encourage you to look around those webpages.
Her daughter Elyssa wrote one of the chapters in the book and is promoting the book and the information relevant to teenagers at the place where teenagers are most likely to see it – on MySpace (you see – it’s not just music bands who caught onto this trick – serious information can be promoted at MySpace as well).
The main audience for this book are teenagers themselves and their parents – I think in this order although officially the order is reversed. Secondarily, the audience are teachers, administrators and officials in charge of school policy. Who this book is not targeted to are scientists and book reviewers because there are no end notes!
Anyway, considering that the main audience are teens, their parents and teachers (i.e., laypeople), the book is admirably clear and readable. The book starts out with presenting the problem – the chronic sleep deprivation of adolescents in modern society – and provides ample evidence that this is indeed a wide-spread problem. It continues with a simple primer on physiology of sleep and circadian rhythms, followed by a review of the current knowledge of the negative consequences of chronic sleep deprivation: from susceptibility to diseases, through psychological and behavioral problems, to problems of physical and mental performance.
A whole chapter – the one I found most interesting – is devoted to the role of sleep in various kinds of memory and the negative effects of sleep deprivation on learning – both declarative and episodic memory, as well as kinesthetic memory needed for athletic performance and safe driving. This is where I missed the end notes the most.
Throughout the book, Dr.Emsellem makes statements of fact about sleep that are obviously derived from research. I’d like to see the references to that research so I can evaluate for myself how strong each such statement is. Although my specialty is chronobiology (physiology, development, reproduction, behavior, ecology and evolution) of birds, and secondarily that of mammals, reptiles, invertebrates and microorganisms (I could never quite get excited about clocks in fish, fungi and plants, or molecular aspects of circadian rhythms, or medical aspects of human rhythms), I am quite familiar with the literature on sleep, including in humans.
Thus, I know that the statements in the book reflect scientific consensus but that the meaning of “consensus” is quite elastic. In some cases, it means “there is a mountain of evidence for this statement and no evidence against it, so it is highly unlikely that this will change any time soon”. In other cases it means “there are a few studies suggesting this, but they are not perfect and there are some studies with differing results, and this can stand for now but is likely to me modified or completely overturned by future research”.
Having end notes would help the expert reader see how weak or strong each one of these findings is, and would also be suggestive to lay readers that the statements in the book are supported by actual research and are not just the author’s invention as seen in so many self-help books. End notes and references add to the believability of the text even if one does not bother to check the papers out.
The book then turns to variety of factors, both biological and social, that conspire to deprive our teens of sleep, both from the perspective of a sleep researcher and from the perspective of teenagers. Little snippets of teenagers’ thoughts on the topic are included throughout the book and add an important perspective as well as make the book more fun to read. Otherwise, the “case studies”, the bane of so many psychology books, are kept to the minimum, discussed very briefly, and used wisely..
In the next section, Dr.Emsellem turns to solutions. First, she present several tests of sleep deprivation that readers can administer themselves in order to self-diagnose the problem. She then describes ten different strategies that parents and teens can work on together in order to solve the problem of sleep deprivation and all the concomittant negative effects (and Alyssa adds her own chapter on the teen perspective on how those can work). If that does not work, she describes additional methods that a sleep doctor may prescribe to help solve the problem. There is also a short chapter describing a couple of other sleep disorders, e.g., sleep apnea, that also contribute to sleep deprivation in affected individuals.
The last portion of the book addresses the social aspects of sleep deprivation and changes that parents and teens can make in their homes, as well as broader community, towards solving the problem. For adults, being a role model for the child is important and this requires paying attention to one’s own sleep hygiene.
The very last portion is really the raison d’etre of the book – how to make one’s community change the school starting times. The author presents a couple of examples of school districts in which such change was enacted, the strategies parents used to force such changes and the incredible positive results of such changes. The whole book is really designed to provide information to parents and teens who are working on changing their local attitudes toward school starting times.
The schools used to start about 9am for most of the century (and before). Then, due to the pressure from business and economic (read “busing”) woes of school districts, the school starting times started creeping earlier and earlier starting back in 1970s until they reach the horribly early times seen today in many places, requiring kids to get up as early as 5am in order to catch the school bus on time. As a result, high schoolers (and to some extent middle schoolers and college students) sleep through the first two periods in school, feel weak and groggy all day long, more easily succumb to diseases, have trouble learning and performing well in school and the athletic field, and are in too bad mood to be pleasant at home – this is not the natural state of things as much as the stereotype of the “grouchy teen” is prevalent in the society, it is mainly due to sleep deprivation and the biggest factor causing sleep deprivation are early school starting times.
In places in which enlightened and progressive school boards succumbed to the wishes of parents and students, i.e., in places in which parents and students used smart diplomatic tactics to engender such change, the positive results are astounding. The grades went up. The test scores went up. The students are happy. The parents are happy. The teachers are happy. The coaches are happy because their teams are winning all the state championships. There is a decrease in tardiness and absences. There is a decrease in sick days and even in numbers of diagnoses of ADD and depression in teens. There is a drop in teen crime. There is a drop in car accidents involving teens (by 15% in one place!). The whole county feels upbeat about it!
While the book makes me – a scientist – thirsty for end notes and references, it does remarkably well what it was designed to do – arm the parent and kids with knowledge needed to make a positive change in their communities – a change that is necessary in order to raise new generations to be healthy and successful, something we owe to our children.
We should do this no matter how much it costs, but the experiences from places in which the changes were made, contrary to doomsayers, is that there was no additional cost to this at all. The changes were implemented slowly and with everyone involved pitching in their opinion and their expertise until the best possible system was arrived at, adapted to the local community situation. No new buses were needed to be rented. No unexpected new costs appeared. And having a safe, happy community saved money elsewhere (e.g., accidents and crime rate decline). And it worked wonderfully everywhere.
So, get the book and let your child read it, you read it, give a copy to other people in your community: the teachers, the school principal, the pediatrician, the child psychologist, the school board members, the superintendent of education and the governor. This is something that is easy to do, there are no good reasons against it and the health and the future of our kids is at stake. It is something worth fighting for and this book is your first weapon.
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Bora ZivkovicAbout the Author: Bora Zivkovic is the Blog Editor at Scientific American, chronobiologist, biology teacher, organizer of ScienceOnline conferences and editor of Open Laboratory anthologies of best science writing on the Web. Follow on Twitter @boraz.