Thursday, February 18, 2010

It's not what you eat, but when you eat

Submitted by Armen Hareyan on Dec 22nd, 2009 

If you have struggled with your weight for a long time, you probably blame your diet failures on a lack of willpower. Let me tell you, willpower has nothing to do with it. I’d wager that the problem isn’t what you eat, it’s when you eat it. Our circadian rhythms regulate our eating patterns. In simple terms, our eating patterns are screwed up. Think of jet lag, only with food.

Most overweight people become out of sync because they either skip breakfast or they eat too little in the morning. They go against their body’s actual needs (fuel in the morning) and make up for it by over-fueling later.

When your body awakens from its eight-hour slumber, it is primed to seek food. Your metabolism is revved up, and levels of certain hormones (cortisol and adrenaline) are at their highest. Your brain needs energy (glucose) immediately.

If you don’t break your eight-hour fast or you eat too little, your brain needs to find another source of fuel. So it activates an emergency system that pulls energy from muscle and destroys muscle tissue in the process. Then when you eat later, the body and brain are still in high-alert mode, so the body saves energy from the food as fat.

Compounding the problem, serotonin levels are highest in the morning. This means that you’re least likely to crave sweets and starches when you first wake up, and you may not feel much like eating. But as the day wears on, serotonin levels dip and the cravings kick in. If you eat these foods, brain serotonin rises, and you begin to associate good feelings with them. This connection between carbs and calm creates an addictive cycle.

People who skip breakfast or engage in other out-of-sync eating behaviors (see box above) set themselves up for metabolic disaster. Their metabolism sputters. They’re plagued by midafternoon fatigue and/or moodiness, so they rev up or unwind with candy bars and sugary coffee drinks. Their bodies burn less of what they eat as fuel and store more of it as body fat. Their bodies lose muscle and gain fat - lots of it.

The Big Breakfast Diet: Eat Big Before 9 A.M. and Lose Big for Life
Written by Daniela Jakubowicz MD
Publisher: Workman Publishing Company (December 15, 2009)
ISBN-10: 0761154930

Tuesday, February 9, 2010

FISH OIL CAN FIGHT DENTAL DISEASE

Published Date: 09 February 2010 
The discovery of a new natural weapon against dental disease has been welcomed by the UK's leading oral health information charity.
Following a five-year study involving elderly participants in Japan, fish oil has been found to help combat mouth infection and boost oral health in the process.

Dental examinations revealed that a lack of the essential omega-3 fatty acids found 
in fish oil in people's diets had strong links with the progression of periodontal (gum) disease.

The new findings, recently published in the Nutrition journal, also revealed that omega-3 fatty acids were strongly effective against a range of oral bacteria.

This news comes in light of similar findings from a US National Institute for Health-sponsored study. Lead author Dr C.B. Huang, from the Oral Health Research Centre at the University of Kentucky's College of Dentistry, commented on the dental health benefits of fish oil.
"The anti-bacterial part of the omega-3 fatty acids could be very important. Certainly, it could be a potential new use of omega-3 fatty acids in the future."

Following these recent journal* findings, Dr. Huang confirmed that ongoing research into anti-bacterial activity would include investigating products such as chewing gum.

In light of the news of these beneficial oral health effects, the British Dental Health Foundation Chief Executive, Dr. Nigel Carter BDS LDS (RCS), commented: "These findings illustrate how the consequences of our diet can be linked to gum disease, the most common dental hygiene issue.There are hundreds of bacteria in our mouths at any one time that contribute to gum disease, which not only threatens tooth loss but, significantly, overall health.

"A healthy mouth can lead to a healthy body so a good oral healthcare routine, including brushing teeth twice a day with a fluoride toothpaste and making regular visits to the dentist are just as important as a healthy, balanced diet."

With evidence of a poor diet linked to a third of all cancer cases, Dr. Carter also stressed: "Eating fish can help lower the risk of cancer, as can an increase in eggs, fruit and vegetables."

The Foundation encourages members of the public with any concerns about the effects of their diet on their teeth to contact the National Dental Helpline on 0845 063 1188.

Self–examination is another simple way of looking after yourself. The Foundation, who run a Mouth Cancer Action Month campaign each November, encourage all members of the public to check their mouths regularly for ulcers which do not heal within three weeks, red and white patches in the mouth and unusual lumps and swellings in the mouth and neck.


*Source: Molecular Oral Microbiology, Volume 25 Issue 1, pages 75-80 "A novel bioactivity of omega-3 polyunsaturated fatty acids and their ester derivatives" Authors: C.B. Huang, J.L Ebersole
ENDS
 

Monday, February 8, 2010

Study: Soda drinkers at increased risk of pancreatic cancer

A study published today in the journal Cancer Epidemiology, Biomarkers & Prevention finds that people who drink two caloric soft drinks a week have nearly double the risk of developing pancreatic cancer when compared to those who drink less.

The research tracked 60,524 men and women in the Singapore Chinese Health Study for 14 years and found that the soft-drinkers increased their risk of contracting the deadly cancer by 87 percent. The relationship held up even when smoking and a handful of other habits were taken into account. The study did not look at consumption of diet soda; soft drinks were defined as "sugar-sweetened carbonated beverages."

The study, funded by the National Cancer Institute, notes that lifestyles in Singapore have much in common with those in the U.S. and that the findings should apply to Caucasians as well as to the Asians who were tracked.

Lead author Mark Pereira, an associate professor in the School of Public Health at the University of Minnesota, suggests that the high level of sugar in sodas may boost insulin levels in the body, which in turn might spur the development of pancreatic cancer cells.

But no such connection was found between drinking fruit juices, whose sugar content often matches that of soft drinks.

The findings, while provocative and frightening, could use some perspective. First, the total number of pancreatic cancer cases found over the 14 years of the study was just 140. Of those, 18 occurred among people who'd reported consuming two or more sodas per week, and 12 among those who drank less than two; 110 occurred in people who'd reported drinking no soda.

The study acknowledges that those small numbers might make the association a little more tenuous, "limiting the power" of the data and "giving potential to a chance association." It also cites four earlier studies that examined the soda-pancreatic cancer link that came to varying conclusions, including finding no link at all to finding an association for women but not for men.

Speaking on behalf of the American Beverage Association, consultant Richard H. Adamson said, "The study is, in my opinion, a weak study." Adamson, former vice president for science and technical affairs for the beverage association and, before that, a researcher at the National Cancer Institute, says that the study was "very small with regard to number of cases" of pancreatic cancer for major conclusions to be drawn from its data.

Further, Adamson says, the researchers didn't correct for other known pancreatic-cancer risk factors such as chronic pancreatitis, high-fat diet, workplace exposure to chemicals or gender (males are much more likely to get this cancer than females). The fact that the association didn't hold for juice raises questions, he said, as the sucrose in Singapore soft drinks "breaks down into the same thing that's in juice."

In the end, Adamson said, "The study doesn't scare me. I continue to drink soft drinks."

I'm not a soda drinker, and this study doesn't inspire me to start sipping. But while many public-health advocates believe we'd all be better off without soda in our lives, I'm not sure that if I did enjoy soda I'd stop drinking on the basis of this study alone. Because pancreatic cancer is relatively rare, even doubling your risk leaves your individual risk pretty low.

On the other hand, given the grim prospects for surviving pancreatic cancer (fewer than 5 percent of those diagnosed are alive after five years), and that fact that there's no screening test and very few treatment options, anything we can do to reduce our risk might be worth considering.

How about you? Are you a soda drinker? Does this study make you inclined to cut back?

For more health news, please follow me on Twitter! http://twitter.com/jhuget.

washingtonpost.com

By Jennifer LaRue Huget | February 8, 2010; 12:05 AM ET

Categories: Cancer , Nutrition and Fitness

Wednesday, February 3, 2010

Mastering The Mystery Of Sleep

Dr. Joseph Mercola

Posted: February 3, 2010 09:05 AM

Sleep is one of the great mysteries of life. Like gravity or the quantum field, sleep is so fundamental that scientists still don't know exactly what it is. We are learning more about sleep every day, but we still don't understand exactly why we sleep at all. (1)

This report will not solve the mystery of sleep, but will seek to show you how you can get into harmony with the natural cycles of your own brain and body. There is no better example of optimal wellness than to be in harmony with your deepest function: sleep.

The first step is to value sleep as one of your most precious resources for health and happiness. If you do that, you could figure out all the other things that would help you to sleep really well. So the bulk of this report will be all about that first step...but you will also get some of my favorite tips.

Sleep Is an Active Process

We used to think the brain simply shut down for a rest once a day. But the brain doesn't shut down at all during sleep...not like it does under general anesthesia or in a coma. (2) Sleep is an active process, which might better be described as a deeper form of consciousness than as a lack of it.

In fact, there are respected spiritual traditions that describe deep sleep as a vast field of consciousness without content. (3) And advanced meditators have done their thing wired to an EEG machine. Guess what? They go right into slow high amplitude brain waves all over the cortex. (4) They are sitting there on a cushion with the EEG of dreaming or even of deep sleep...and then proceed to describe their experience. (5)

Sleep Away Stress

Did you know that good sleepers and poor sleepers experience about the same number of daily minor stressful events? But good sleepers are less disturbed by these events. (6) Poor sleepers experience both their minor and major life events as being more negative than do good sleepers.

Scientists call this mindset "negative affective reactivity." They can actually predict whether or not a person will rate an upcoming event as being emotionally negative just by looking at the person's brain waves ahead of time. (7) High frequency brain waves on EEG, particularly in the right prefrontal cortex, are a sign of negative emotional arousal. The problem with high neurological arousal is that it can turn into a bad habit. An overly aroused right prefrontal cortex calls for the release of cortisol and other stress steroids that initially help the body in stress.

But continuous high levels of these powerful hormones ultimately cause some of our most serious health concerns...including heart attack and stroke.

Does Stress Cause Poor Sleep, or Does Poor Sleep Cause Stress? Answer: YES

We've known for quite some time, that activation of the hypothalamic-pituitary-adrenal axis increases arousal and causes sleeplessness.

Stress causes poor sleep. And research shows that insomniacs do have elevated cortisol in the middle of the night, when cortisol should be at its lowest. (8) Conversely, poor sleep causes stress. But more recently, researchers have discovered that good quality sleep the night before a stressful event can protect you from negative health consequences. Even though you will still encounter stressful events in your life, good quality sleep gives you better brain chemistry to deal with those events.

Would that be of value to you?

Would Enhancing Your Immune System be of Value?

What is true for brain chemistry is also true for the immune system. Ordinarily, a stressful event will trigger the release of natural killer cells, but in one study, women whose sleep was interrupted for just one night prior to a stressful event had significantly weaker immune responses. (9) The poor sleepers failed to recover from the stress as well as those who slept well.

And researchers have found that less time spent dreaming (REM sleep) was associated with higher evening cortisol levels for healthy men of all ages. (10)

Sleeping Well Can Protect You from Stress Induced Depression ... and a Variety of other Mood Disorders

Serotonin is an important brain neurotransmitter. Altered serotonin activity has been associated with a host of problems such as aggressive and angry behaviors, clinical depression, obsessive-compulsive disorder, migraine, irritable bowel syndrome, tinnitus, fibromyalgia, bipolar disorder, and anxiety disorders. (11)

In a study reported in Journal of Sleep Research, stress plus restricted sleep caused serotonin receptors in the brain to become less sensitive, while stress following sleep had no such negative effect. (12) It is not known how sleep provided this beneficial influence on brain chemistry.

Sleep Improves Performance and Memory

Whenever you are trying to learn something new, such as important information or a new skill--and especially if you are going to be tested on it--please get good quality sleep after the training period and before the test.

In a very interesting study, there were two groups of individuals who trained for a new keyboard skill and were tested on it 12 hours later. One group trained at 10 AM and was tested at 10 PM. The other group trained at 10 PM and was tested the next morning at 10 AM ... after sleep.

Guess what? Sleep increased motor speed by 20 percent without loss of accuracy. (13) Remember, group one was not impaired in any way. You might have thought they would do better having trained when they were fresh in the morning. But sleep proved to be the valuable variable.

Would a 20 percent Increase in Performance be Useful to You?

Sleep is absolutely essential for long-term memory formation and more. You may have heard that everything you have ever seen, heard, tasted, smelled, or touched is recorded in your unconscious mind. Actually, that is false. The vast majority of sensory input is deleted and lost forever. Only the information your brain recognizes as important to your life ever makes it into your memory. Even then, the important stuff is held in temporary memory only until you sleep on it. (14)

Valuable new information and valuable new skills are added to your long-term memory -- only during sleep . But sleep takes it one step further ... While you are sleeping, your brain integrates the day's new information along with existing memories and in light of your values, your goals, and your purpose. That is why I have strongly suggested, in my paper on goal setting, that you do a visualization exercise on your goals just before going to bed each night.

How to Get Your Brain to Solve Problems While You Sleep!

Do you remember how the phrase, "think outside the box" got started? It came from the nine dots puzzle, where you had to connect three rows of three dots forming a square. You had to connect all the dots without lifting the pencil off the paper. (15) The solution requires an insight: you have to extend your lines beyond the box formed by the dots. You have to "think outside the box" to solve the puzzle.

In research involving a similar task, progress could be made in two ways. Slow and laborious-- or with sudden insight. Subjects who slept for eight hours after being presented with the puzzle were twice as likely to gain the key insight. (16) Valuable information, isn't it? Now you know why visualization before sleep works so well. While you are sleeping, your brain searches for new ways to view the information you gained during the day. And it does so according to the vision you provide during the visualization.

Are you starting to get the idea?

Sleep is a precious resource, and you are learning how to get into harmony with it...to neutralize stress, improve your mood, boost your performance and memory, and gain valuable insight into whole new possibilities for your life!

What else could you possibly ask for?

How About Sleeping Away Those Extra Pounds? If you're like most people in modern society, you have to keep an eye on your weight. Americans alone spend $35 billion (each year) on weight-loss products. (17) And what do we have to show for it? 119 million Americans are overweight or obese. And 64 percent are losing the body fat battle.(18) Why? America's trend toward obesity just happens to match its trend toward voluntary sleep restriction. And 70 to 75 percent of Americans report having one or more persistent symptoms of dis-harmonious sleep. (19, 20)

Any connection between obesity and sleep loss?

It turns out sleep-loss is a double whammy for anyone looking to shed pounds because of two hormones that regulate hunger and appetite. Cells in the lining of your stomach secrete the hormone ghrelin. Ghrelin travels to your brain and gives you the urge to eat. Leptin does just the opposite. Fat cells produce it when you've had enough to eat. Leptin in you bloodstream gives you the feeling of satiety. It's a good thing if you're trying to lose weight.

Just two days of restricted sleep caused an 18 percent decrease in plasma leptin levels and a 28 percent increase in ghrelin levels in young healthy men. (21) The result was increased hunger and an appetite for carbs. Definitely not good if you're trying to lose weight.

So in addition to regular exercise and eating according to your metabolic type, getting enough good quality sleep is extremely valuable for maintaining your ideal weight .

Good Sleep Helps Prevent Diabetes Mellitus and Metabolic Syndrome

In one clinical experiment, healthy young men were restricted to just four hours of sleep for six nights and then allowed to recover for six nights. During the sleep-debt period thyroid function went down, while cortisol levels and sympathetic activity went up. (22) But the most important finding in the study was that glucose tolerance tanked during the temporary sleep debt. So chronic sleep-loss could be expected to contribute to the onset of diabetes. (23) And indeed, when a group of men were followed from roughly 1988 through 2004, those who got only five and six hours of sleep per night were twice as likely to develop diabetes. (24)

Poor sleep was associated with a 44 percent increase in the odds of having pre-diabetes among 210 volunteers averaging 46 years of age. (25) Metabolic syndrome is not only the precursor to diabetes, but also to high blood pressure, cardiovascular disease, and other life-threatening diseases. Sleep is a valuable means to combat these problems as well.

Sleeping Well Could Save Your Life

Sleeping too little or too much increases your chances of dying from all causes by up to 15 percent. (26) People who have normal sleep patterns get less cancer. (27) For every hour a woman sleeps more than the recommended seven to eight hours per night, the chances of her getting breast cancer go up by six percent. (28)

Tumors grew two to three time faster in laboratory animals with severe circadian rhythm dysfunction. (29) And working the night shift robbed nurses of a normal dose of melatonin, a powerful anti-oxidant known to protect DNA. The research suggests a correlation between decreased melatonin, elevated estrogen, and the observed higher incidence of breast cancer among night shift nurses. (30)

Your chances of having a heart attack go up by 45 percent if you sleep five hours a night or less, and by 38 percent if you sleep more than nine hours a night. (31)

Getting either too much sleep or too little sleep are both out of harmony with a natural circadian rhythm. Likewise, shift workers run a much higher risk of heart attack as compared to people whose waking and sleeping hours are more normal. (32) Having to change shifts frequently and having to sleep during daylight hours are quite damaging -- possibly even deadly. Here is another interesting study: healthy subjects restricted to 4 hours sleep had 8 hours of high blood pressure the next day. Good quality sleep resulted in normal blood pressure the next day in the control group. (33)

Sleep is valuable here again because the hormone melatonin signals the entire body to shift from daytime running-around mode into night-time healing mode. Melatonin, which is secreted only in total darkness, also stimulates the nighttime release of another equally valuable hormone -- growth hormone. (34)

Sleep and Grow Younger?

Another great benefit of sleep is the nightly release of growth hormone. Growth hormone is vital for normal development of children, but it has wonderfully beneficial effects in adults as well:

• Makes your bones stronger

• Increases your muscle mass through the creation of new muscle cells

• Promotes lipolysis, which helps you lose body fat

• Increases protein synthesis and stimulates optimal maintenance
of all internal organ

• Supports your pancreas' ability to make insulin

• Stimulates your immune system.

All together, growth hormone makes you look and feel younger. Which is why you hear so much about supplements containing growth hormone precursors, and why professional body builders and athletes sometimes risk injecting synthetic growth hormone in artificially high amounts. But you already have a natural way to get your very own growth hormone delivered in just the right concentration at just the right time, every night...if you sleep well.

Growth hormone is released from your pituitary gland just as you enter the deep sleep part of your normal sleep cycle. (35)

A normal sleep cycle goes from light sleep into deep sleep and then back out to the lighter dreaming REM sleep. Most people have about four of these cycles during an optimal seven to eight hour night's sleep. But if you stay up to watch Letterman and still have to get up at 6 AM...you just performed your own voluntary sleep deprivation experiment on yourself. And you just cut your normal dose of growth hormone in half. And you wonder why you feel old on some mornings? It could be because you're hung over with yesterday's half-repaired cellular damage.

Sleep is for re-growing all the tissues of your body so you can feel and be ready to go in the morning. But you need to value sleep enough to go to bed. Now You Know Why I Believe Sleep Belongs at the Very Top of Your List -- Every Day

If you want to maximize your health and effectiveness, live long and be fulfilled in your purpose, try as many of these 33 strategies as possible:

• Review all the benefits you get from sleep--and put it at the top of your list. Value sleep highly as the magical resource it is for you. Whether you consider sleep to be a purely physiological function or a more spiritual encounter with your deeper consciousness...value it highly.

• Go to bed around the same time each night, ideally around 10 PM. But take time before that to prepare. Some researchers even feel that every hour of sleep before midnight is equal to two hours of sleep after midnight.

• Create your own pre-sleep ritual that goes beyond your normal teeth brushing and other practical activities. Make this a special time to set the tone for your journey into deep consciousness. Light candles, read inspirational or spiritual literature, and let your mind consider the big picture.

• Take some time to visualize how you would like tomorrow to be for you. See, hear, and feel what it will be like when you reach your goals. Connect with your overall mission and purpose. Remember, this will tell your brain which of the data stored in temporary memory should be flagged for transfer into longterm memory. New insights may be waiting for you in the morning.

• Create a morning ritual designed to capture these insights, perhaps a special journal on your bedside table. Taking time to record any impressions upon awakening sends a powerful message to your deep consciousness. It says you do in fact value the entire sleep process. It also says you expect results.

• Design your bedroom primarily to support good sleep. Keep it clean and uncluttered...no overflow storage in there, please. Get high quality linens and pillows. Sleep is far more important than half the things you spend money on now. Have complete control of the lighting in your bedroom. Be able to make the room totally dark.

• Avoid turning on the light if you have to go to the bathroom. Any bright light will shut off melatonin production.

• Listen to white noise or relaxation CDs. Some people find the sound of white noise or nature sounds, such as the ocean or forest, to be soothing for sleep.

• If possible try to awaken naturally without the use of an alarm. Your brain will know when it has had enough sleep. Ideally you should wake up with the sunrise. If you must get up before dawn, use a dawn simulator alarm clock which either comes with a light or causes one of your lights to gradually increase in intensity to mimic the rising sun. Many people find these very effective and certainly less disturbing than a loud alarm that can disrupt your adrenal glands and cortisol levels.

• If you must sleep during the day, make the extra effort to completely block all
daylight from your bedroom.

• Dim the lights in your house around 8 PM. Light stimulates the release of
cortisol and shuts down the release of melatonin.

• Stop watching TV or using your computer by 8 PM

• Avoid snacking just before bedtime, particularly grains and sugars. These can raise your blood sugar and inhibit sleep. Then later, when your blood sugar drops, you might wake up and not be able to fall back asleep.

• Keep the temperature in your bedroom no higher than 70 degrees F.

• Wear socks to bed. Due to the fact that they have the poorest circulation, the
feet often feel cold before the rest of the body.

• Eat a high-protein snack several hours before bed. This can provide L-tryptophan, a precursor to melatonin and serotonin.

• Talk to your doctor about reducing or avoiding as many drugs as possible. Many medications, both prescription and over-the-counter, may have effects on sleep.

• Avoid caffeine as much as possible.

• Keep electrical devices as far away from the bed as possible so their electromagnetic fields do not interfere with your nervous system.

• Avoid alcohol. Too much alcohol interferes with deep sleep and will prevent you from getting its healing benefits.

• Avoid foods that you are sensitive to.

• Don't drink any fluids within two hours of going to bed so you won't have to get
up to go the bathroom.

• Take a hot bath, shower or sauna before bed if you have trouble falling asleep.

• Journaling may be helpful if you often lay in bed with your mind racing. Writing you thoughts down may allow you to let go of your concerns before bed.

• Lose weight. Being overweight can increase the risk of sleep apnea, which will
prevent a restful night's sleep.

• Remove your clock from view. It will only add to your worry when constantly
staring at it...2 AM...3 AM...4:30 AM...

• Keep your bed for sleeping. If you are used to watching TV or doing work in bed, you may find it harder to relax and to think of the bed as a place to sleep.

• Have your adrenals checked by a good natural medicine clinician. Scientists have found that adrenal stress can interfere with sleep.

• If you are menopausal or peri-menopausal, get checked out by a good natural medicine physician. Hormonal changes at this time may cause problems if not properly addressed.

• Don't change your bedtime. You should go to bed, and wake up, at the same times each day, even on the weekends. This will help your body to get into a sleep rhythm and make it easier to fall asleep and get up in the morning.

• Make sure you are exercising regularly. Try to make it part of your morning ritual. Exercising in the evening--within a few hours of sleep--may actually serve to stimulate your nervous system and make it more difficult to easily fall asleep.

• Get help if you need it. If after trying everything we have discussed, you still cannot get good quality sleep, by all means do discuss your problem with your physician.

After experimenting with these strategies, feel free to cross out those that do not make sense
to you. Use the rest as seeds to develop your own style of sleeping. I hope you will continue learning about sleep and how you can improve this important part
of your life.

Pleasant dreams...


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30. Schernhammer, E.S., Rosner, B., Willett, W.C., Laden, F., Colditz, G.A., & Hankinson,
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31. Ayas, N.T., White, D.P., Manson, J.E., Stampfer, M.J., Speizer, F.E., Malhotra, A., et
al. (2003). A prospective study of sleep duration and coronary heart disease in women.
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32. Knutsson, A., Hallquist, J., Reuterwall, C., Theorell, T., & Akerstedt, T. (1999). Shiftwork
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35. Takahashi Y, K.D. (1968). Growth hormone secretion during sleep. J Clin Invest, 47(9),
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Tuesday, February 2, 2010

John Pranger: The smoke screen of animal research

By John Pranger 

“The medical establishment has become the major threat to health.”
— Ivan Illich in Limits to Medicine: Medical Nemesis, the Expropriation of Health, 1976

Animals are used by pharmaceutical and chemical companies to test the toxicity of drugs and other substances, including cosmetics, household cleaners, and pesticides—and tobacco. This practice has been regularly criticized by doctors and scientists who maintain that animal testing is unscientific, erroneous, and a danger to human health. It merely performs an alibi function for corporations and governments, who hope to protect themselves thereby from legal liability.

This alibi function was confirmed by James D. Gallagher, then director of medical research for Lederle Laboratories, who complained in the Journal of the American Medical Association in 1964: “Another basic problem which we share as a result of the regulations and the things that prompted them is an unscientific preoccupation with animal studies. Animal studies are done for legal reasons and not for scientific reasons. The predictive value of such studies for man is meaningless—which means our research may be meaningless.”

See also

Abolitionists in animal rights movement push for vegan society

Peter Fricker: Mountain View centre must be accountable for welfare of captive animals

The biological variations between species make the results of experiments done on one species inapplicable to any other species, including humans. In addition to this, the various diseases which plague human beings either do not occur naturally in non-humans or they take on a very different form. Put simply, animals can never have human disease due to the basic biological fact that they are not human.

Cigarette smoking is a factor in many diseases, causing an estimated 443,000 deaths each year in the U.S. alone. Why are cigarettes still legal when they are proven harmful? Epidemiology has shown, for instance, that persons who smoke are far more likely to die of lung cancer than persons who do not smoke. Numerous large population studies have been undertaken, and there is not a single retrospective or prospective controlled study that has failed to show that cigarette smoking causes human lung cancer.

In stark contrast to the consistently positive findings linking cigarette smoking to lung cancer in humans, the results of decades of animal experiments are highly contradictory. Most animal studies have failed to show that cigarettes cause cancer.

Perversely, denying medical facts, researchers are forcing animals to inhale cigarette smoke to this day, no scientists having yet succeeded in causing the human type of lung cancer in animals. In 1975’s The Unseen Fight Against Cancer, Dr. Thelma Brumfield Dunn writes: “the induction of lung cancer by tobacco smoking has not been achieved. Almost every conceivable experiment has been devised to induce lung cancers in animals that would duplicate the lung cancers found in man. Chickens and dogs were made to smoke and to inhale, but no convincing lung cancers developed. Hundreds of mice spent a lifetime in smoke-filled rooms yet no increase in lung cancer was found.”

Because of animal studies’ failure to show that cigarette smoking causes cancer, wider and speedy acceptance of the cigarette-lung cancer theory has been seriously retarded, although it is firmly based on studies of actual human populations. Tobacco companies have used the legal alibi of animal testing to keep their products on the market and to frustrate all attempts at instituting meaningful regulation and public health measures. In 1993, the New York Times quoted sworn testimony of William Campbell, then president and CEO of cigarette manufacturer Phillip Morris USA:

Q: “Does cigarette smoking cause cancer?”

A: “To my knowledge, it’s not been proven that cigarette smoking causes cancer.”

Q: “What do you base that on?”

A: “I base that on the fact that traditionally, there is, you know, in scientific terms, there are hurdles related to causation, and at this time there is no evidence that -- they have not been able to reproduce cancer in animals from cigarette smoking.”

Animal studies are almost unbelievably contrived and crude. Dogs with erections (don’t ask how) were forced to inhale cigarette smoke. Most of the dogs failed to maintain an erection after the smoke was inhaled. In the Journal of Urology in 1987, researchers said this observation lent support to the clinical observation that smoking interfered with a man’s ability to maintain an erection.

Laughable or worrying? Why do we have to give our money to people who conjure up such mad science behind locked doors? Why does government continue funding animal experiments with our taxes in spite of their proven inability to cure or prevent disease?

Nearly a century of tormenting animals with cigarette smoke and what’s the upshot? 5.4 million Canadians are addicted to cigarettes—the leading cause of preventable death—and 45,000 Canadians die from smoking each year and that number is growing. When will the “scientists” be satisfied that smoking is unhealthy and that we don’t need their “confirmation” to know this?

John Pranger is the director of communications for the Animal Defense & Anti-Vivisection Society of British Columbia.

Monday, November 16, 2009

Vitamin D and Endurance Exercise

Nutrition
November 16 2009
Comments
 

Low vitamin D levels are very likely limiting your running performance, and may compromise your health.

Written by: Reyana Ewing, MPH, RD, CLE

As runners we want to do everything possible to perform well and have a great season. We are meticulous about our training schedules, hydration, sleeping habits, etc. Yet many times we fall short when it comes to nutrition.

My Story

In the summer of 2008 I started to feel rather lethargic during workouts and I struggled to maintain my normal training paces. My recovery from my harder efforts and long runs took longer than usual. I immediately and incorrectly assumed I had low serum ferritin levels indicating iron deficiency anemia.

One colleague to whom I lamented about my chronic fatigue asked me if I had checked my vitamin D levels. “Vitamin D levels?” I exclaimed. I live in California, it is summer, and I am outside way more than the recommended 20 to 30 minutes a day. There is no way I could be vitamin D deficient, especially since in addition to being exposed to sun most days, I eat a very balanced diet that includes a daily multivitamin supplement. However, a visit to my doctor confirmed that my serum 25–hydroxy-vitamin D (25(OH)D) value was dangerously low (18 ng/ml). Normal levels are between 40-70 ng/ml. And for those with chronic diseases such as cancer, heart disease, diabetes, and multiple sclerosis, normal blood levels should be between 55-70 ng/ml. I was shocked.

I immediately started daily supplementation with 1000 IU of vitamin D (Vitamin D3). After 8 weeks, my 25(OH)D level had improved somewhat (28 ng/ml). I did feel slightly better, but I wanted to recover completely, so I upped my dosage to 2000 IU daily. A few weeks later my levels were within the normal range (56 ng/ml). I felt noticeably stronger and was able to hit my usual paces during training. And in October 2008, I set a half marathon personal record.

Deficiency

This was my very first experience with vitamin D deficiency and I have since learned that vitamin D deficiency is becoming an epidemic worldwide, not only in geographic regions where sun exposure is limited. And my discussions with fellow dietitians working with college runners and professional athletes in generally sunny states (Texas and Florida) confirmed the alarming prevalence of vitamin D deficiency across ethnicity and gender.

Athletes who live in northern latitudes (north of 35 degrees), or use sunscreen consistently, perform their sport indoors, or keep their skin covered are at the greatest risk. Melanin affects the production of vitamin D. So those with more melanin or darker skin produce less vitamin D. Since vitamin D is a fat-soluble vitamin, athletes with fat malabsorption problems such as cystic fibrosis, Crohn’s disease, and celiac disease are at risk for deficiency. Those who have normal levels typically (around 50 ng/ml) live in sub-equatorial Africa and work outdoors for most of the summer.

Once thought of as being primarily involved in bone development, activated vitamin D (calcitriol), a steroid hormone, is responsible for regulating more than 1000 human genes. Almost every cell in the human body has receptors for vitamin D. Recent research shows that vitamin D deficiency increases the risk of different types of cancer (such as breast cancer and prostate cancer), as well as heart disease, diabetes, depression, autoimmune diseases, hypertension, obesity, gum disease, chronic pain, muscle wasting, inflammation, birth defects, osteoporosis, influenza and colds, etc.

Importance for Endurance Athletes

We are only just beginning to understand the complexity and importance of vitamin D in relation to health. Of importance to athletes is the function of vitamin D as it relates to overall health, bone density, innate immunity, muscle wasting, and exercise-related inflammation and immunity. To train and race optimally, an athlete should not have any nutrient deficiencies.

Bone Health:

Deena Kastor, Olympic Marathoner, broke her foot in Beijing during the 2008 Olympic Marathon. It was discovered that her calcium levels were normal, but her 25(OH)D levels were reported to be around 15 ng/ml. And Kastor lives in sunny California. Because of an early scare with skin cancer, she is known to apply sunscreen for all of her outdoor runs, thus limiting her ability to manufacture vitamin D from sun exposure. Even with the extensive research to show vitamin D and calcium’s role in preventing osteoporosis, elite, college, and high school athletes continue to be deficient in one or both nutrient(s). Stress fractures are quite prevalent in runners and yet so preventable.

Increased VO2 max:

German research studies dating back to the 1950s show that athletes exposed to vitamin D-producing ultraviolet light had improved athletic performance. Other studies showed that athletic performance peaked at the end of the summer. Peak performance was also associated with 25(OH)D levels around 50 ng/ml. In addition, maximal oxygen uptake was found to drop when less ultraviolet rays reached the earth, for example, in the late fall. This is particularly a problem for marathoners training through the summer for fall marathons.

Reduced Inflammation:

After intense exercise, endurance athletes experience inflammation due to elevated levels of pro-inflammatory cytokines. Vitamin D reduces the production of these cytokines while increasing the production of anti-inflammatory cytokines, thereby speeding the recovery process between hard workouts.

Improved Immunity:

In a February 2009 study published in the Archives of Internal Medicine, vitamin D3 levels were tested in 19, 000 Americans. Those with low levels of vitamin D had the highest incidence of colds and influenza. This is important information for endurance athletes who strive to balance heavy training loads and staying healthy.



What can be done?
Check 25(OH)D levels regularly and supplement as needed.
Check for total 25(OH)D and not 1, 25(OH)D, which will tell you nothing about your blood stores. Total 25(OH)D reflects all sources of vitamin D – from food, UV energy (photo-production), and supplementation.
Deficient athletes measuring less than 30 ng/ml should supplement with 20,000 IU to

50, 000 IU of vitamin D3 per week for 8 weeks andrecheck serum 25(OH)D until normal values are attained.
Get regular, safe, twice-daily (5-30 minutes) exposure to sun between the hours of 10 am and 3 pm. Note that sunscreen and glass (being indoors) reduce or block UV energy.
Supplement with 1000 IU to 2000 IU of vitamin D3 to maintain normal levels.
For those living or competing in northern latitudes (north of Atlanta, GA) little to no vitamin D production will occur, so consumption of fortified foods and supplements is a necessity.

Food Sources of vitamin D

There aren’t many naturally occurring foods that contain vitamin D. Most of the foods containing vitamin D have been fortified, for example milk and certain juices.

Table 1. Food Sources of Vitamin D FOOD Serving IU per serving *
Fish liver oils (cod liver oil)                                         1TBSP 1360
Herring, cooked 3 oz                                                                 1383
Wild salmon, cooked 3.5 oz                                                        981
Farm salmon, cooked 3.5 oz                                                      249
Tuna, canned in oil 3.5 oz                                                          200
Milk, non fat, reduced fat, whole (fortified) 8 oz                    100
Margarine, fortified 1 TBSP                                                        60
Egg 1 whole                                                                                    18
Beef, liver 3.5 oz                                                                            15
Cheese 1 oz 12
*IU = International Units


Dietary Supplement Fact Sheet. National Institute of Health (2007)


Caution

High intakes of vitamin D can cause nausea, vomiting, poor appetite, weakness, and constipation. Current safe upper limits are set at 2000 IU by the National Institute of Health, but there are newer data supporting upper limits as high as 10,000 IU per day.

***


Reyana Ewing. Photo courtesy: Fuel to Move.

Reyana Ewing, MPH, RD, CLE is a registered dietitian, sports dietitian and runner based in Santa Rosa, Calif. Find our more about her at www.fueltomove.com

Sunday, May 24, 2009

Brain Power - At the Bridge Table, Clues to a Lucid Old Age

May 22, 2009

By BENEDICT CAREY
LAGUNA WOODS, Calif. — The ladies in the card room are playing bridge, and at their age the game is no hobby. It is a way of life, a daily comfort and challenge, the last communal campfire before all goes dark. 

“We play for blood,” says Ruth Cummins, 92, before taking a sip of Red Bull at a recent game.

“It’s what keeps us going,” adds Georgia Scott, 99. “It’s where our closest friends are.”

In recent years scientists have become intensely interested in what could be called a super memory club — the fewer than one in 200 of us who, like Ms. Scott and Ms. Cummins, have lived past 90 without a trace of dementia. It is a group that, for the first time, is large enough to provide a glimpse into the lucid brain at the furthest reach of human life, and to help researchers tease apart what, exactly, is essential in preserving mental sharpness to the end.

“These are the most successful agers on earth, and they’re only just beginning to teach us what’s important, in their genes, in their routines, in their lives,” said Dr. Claudia Kawas, a neurologist at the University of California, Irvine. “We think, for example, that it’s very important to use your brain, to keep challenging your mind, but all mental activities may not be equal. We’re seeing some evidence that a social component may be crucial.” 

Laguna Woods, a sprawling retirement community of 20,000 south of Los Angeles, is at the center of the world’s largest decades-long study of health and mental acuity in the elderly. Begun by University of Southern California researchers in 1981 and called the 90+ Study, it has included more than 14,000 people aged 65 and older, and more than 1,000 aged 90 or older. 

Such studies can take years to bear fruit, and the results of this study are starting to alter the way scientists understand the aging brain. The evidence suggests that people who spend long stretches of their days, three hours and more, engrossed in some mental activities like cards may be at reduced risk of developing dementia. Researchers are trying to tease apart cause from effect: Are they active because they are sharp, or sharp because they are active?

The researchers have also demonstrated that the percentage of people with dementia after 90 does not plateau or taper off, as some experts had suspected. It continues to increase, so that for the one in 600 people who make it to 95, nearly 40 percent of the men and 60 percent of the women qualify for a diagnosis of dementia.

At the same time, findings from this and other continuing studies of the very old have provided hints that some genes may help people remain lucid even with brains that show all the biological ravages of Alzheimer’s disease. In the 90+ Study here, now a joint project run by U.S.C. and the University of California, Irvine, researchers regularly run genetic tests, test residents’ memory, track their activities, take blood samples, and in some cases do postmortem analyses of their brains. Researchers at Irvine maintain a brain bank of more than 100 specimens. 

To move into the gated village of Laguna Woods, a tidy array of bungalows and condominiums that blends easily into southern Orange County, people must meet several requirements, one of which is that they do not need full-time care. Their minds are sharp when they arrive, whether they are 65 or 95. 

They begin a new life here. Make new friends. Perhaps connect with new romantic partners. Try new activities, at one of the community’s fitness centers; or new hobbies, in the more than 400 residents’ clubs. They are as busy as arriving freshmen at a new campus, with one large difference: they are less interested in the future, or in the past. 

“We live for the day,” said Dr. Leon Manheimer, a longtime resident who is in his 90s.

Yet it is precisely that ability to form new memories of the day, the present, that usually goes first in dementia cases, studies in Laguna Woods and elsewhere have found. 

The very old who live among their peers know this intimately, and have developed their own expertise, their own laboratory. They diagnose each other, based on careful observation. And they have learned to distinguish among different kinds of memory loss, which are manageable and which ominous. 

A Seat at the Table

Here at Laguna Woods, many residents make such delicate calculations in one place: the bridge table. 

Contract bridge requires a strong memory. It involves four players, paired off, and each player must read his or her partner’s strategy by closely following what is played. Good players remember every card played and its significance for the team. Forget a card, or fall behind, and it can cost the team — and the social connection — dearly. 

“When a partner starts to slip, you can’t trust them,” said Julie Davis, 89, a regular player living in Laguna Woods. “That’s what it comes down to. It’s terrible to say it that way, and worse to watch it happen. But other players get very annoyed. You can’t help yourself.”

At the Friday afternoon bridge game, Ms. Cummins and Ms. Scott sit with two other players, both women in their 90s. Gossip flows freely between hands, about residents whose talk is bigger than their game, about a 100-year-old man who collapsed and died that week in an exercise class.

But the women are all business during play. 

“What was that you played, a spade was it?” a partner asks Ms. Cummins.

“Yes, a spade,” says Ms. Cummins, with some irritation. “It was a spade.”

Later, the partner stares uncertainly at the cards on the table. “Is that ——”

“We played that trick already,” Ms. Cummins says. “You’re a trick behind.”

Most regular players at Laguna Woods know of at least one player who, embarrassed by lapses, bowed out of the regular game. “A friend of mine, a very good player, when she thought she couldn’t keep up, she automatically dropped out,” Ms. Cummins said. “That’s usually what happens.”

Yet it is part of the tragedy of dementia that, in many cases, the condition quickly robs people of self-awareness. They will not voluntarily abandon the one thing that, perhaps more than any other, defines their daily existence. 

“And then it’s really tough,” Ms. Davis said. “I mean, what do you do? These are your friends.”

Staying in the Game

So far, scientists here have found little evidence that diet or exercise affects the risk of dementia in people over 90. But some researchers argue that mental engagement — doing crossword puzzles, reading books — may delay the arrival of symptoms. And social connections, including interaction with friends, may be very important, some suspect. In isolation, a healthy human mind can go blank and quickly become disoriented, psychologists have found.

“There is quite a bit of evidence now suggesting that the more people you have contact with, in your own home or outside, the better you do” mentally and physically, Dr. Kawas said. “Interacting with people regularly, even strangers, uses easily as much brain power as doing puzzles, and it wouldn’t surprise me if this is what it’s all about.” 

And bridge, she added, provides both kinds of stimulation.

The unstated rule at Laguna Woods is to support a friend who is slipping, to act as a kind of memory supplement. “We’re all afraid to lose memory; we’re all at risk of that,” said one regular player in her 90s, who asked not to be named. 

Woody Bowersock, 96, a former school principal, helped a teammate on a swim team at Laguna Woods to race even as dementia stole the man’s ability to form almost any new memory. 

“You’d have to put him up on the platform just before the race, just walk him over there,” Mr. Bowersock said. “But if the whistle didn’t blow right away, he’d wander off. I tell you, I’d sometimes have to stand there with him until he was in the water. Then he was fine. A very good swimmer. Freestyle.”

Bridge is a different kind of challenge, but some residents here swear that the very good players can play by instinct even when their memory is dissolving. 

“I know a man who’s 95, he is starting with dementia and plays bridge, and he forgets hands,” said Marilyn Ruekberg, who lives in Laguna Woods. “I bring him in as a partner anyway, and by the end we do exceedingly well. I don’t know how he does it, but he has lots of experience in the game.”

Scientists suspect that some people with deep experience in a game like bridge may be able to draw on reserves to buffer against memory lapses. But there is not enough evidence one way or the other to know.

Ms. Ruekberg said she cared less about that than about her friend: “I just want to give him something more during the day than his four walls.”

Drawing the Line

In studies of the very old, researchers in California, New York, Boston and elsewhere have found clues to that good fortune. For instance, Dr. Kawas’s group has found that some people who are lucid until the end of a very long life have brains that appear riddled with Alzheimer’s disease. In a study released last month, the researchers report that many of them carry a gene variant called APOE2, which may help them maintain mental sharpness. 

Dr. Nir Barzilai of the Albert Einstein College of Medicine has found that lucid Ashkenazi Jewish centenarians are three times more likely to carry a gene called CETP, which appears to increase the size and amount of so-called good cholesterol particles, than peers who succumbed to dementia. 

“We don’t know how this could be protective, but it’s very strongly correlated with good cognitive function at this late age,” Dr. Barzilai said. “And at least it gives us a target for future treatments.”

For those in the super-memory club, that future is too far off to be meaningful. What matters most is continued independence. And that means that, at some point, they have to let go of close friends. 

“The first thing you always want to do is run and help them,” Ms. Davis said. “But after a while you end up asking yourself: ‘What is my role here? Am I now the caregiver?’ You have to decide how far you’ll go, when you have your own life to live.”

In this world, as in high school, it is all but impossible to take back an invitation to the party. Some players decide to break up their game, at least for a time, only to reform it with another player. Or, they might suggest that a player drop down a level, from a serious game to a more casual one. No player can stand to hear that. Every day in card rooms around the world, some of them will.

“You don’t play with them, period,” Ms. Cummins said. “You’re not cruel. You’re just busy.”

The rhythm of bidding and taking tricks, the easy conversation between hands, the daily game — after almost a century, even for the luckiest in the genetic lottery, it finally ends.

“People stop playing,” said Norma Koskoff, another regular player here, “and very often when they stop playing, they don’t live much longer.”