Category Archives: Medicine

Followup on the Science of Sleep

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It’s been a while since I wrote, and some of that is that I’ve been trying to get to bed earlier, and get a more consistent 8 hours of sleep. Since I last wrote, I saw an interesting factoid from an interview with Daniel Kripke, who is the co-director of the Scripps Clinic Sleep Center in La Jolla, California. In this interview, he talked about research he did on more than 1 million Americans that correlated sleep and mortality. There were some surprising findings, which have been corroborated by similar studies in other countries.

The results showed that those who slept between 6.5 and 7.5 hours a night lived the longest. And that those who slept more than 8 hours a night or less than 6.5 hours a night don’t live as long. This is interesting in that most previous writing I have seen suggests that sleeping more is good for you, but these data don’t support that.

Another good point he made was that when people try to get too much sleep, because they think the normal amount is 8 or 9 hours, they may unintentionally develop insomnia. Staying in bed longer than you can sleep will result in wakefulness, and anxiety about not being able to sleep. So for those of you who only can sleep 6.5 or 7 hours, just get up, it won’t hurt your health. In fact, restricting the time in bed is a more effective treatment for insomnia than sleeping pills, according to Kripke.

What we don’t know is which direction the causality runs in this association. Does the amount of sleep you get create your health status, or is it a reflection of underlying health? Do sicker people sleep too little or too much? Or does sleeping too little or too much make you sicker? No one knows for now, so I wouldn’t necessarily rush to change your sleep habits based on this study. But if you are sleeping in the 6.5 to 7.5 hour range, you can relax and not worry about it (especially late at night!)

Now I’ve got to stay up a little longer, so I don’t get too much sleep tonight…

Copyright © 2008 The Psychology Lounge/TPL Productions

The Mystery of the Obesity Epidemic: Solved? (Hint: It’s simpler than you think)

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Was Grandma Right?

It’s been too long since I last wrote, but I’ve been catching up on my sleep. Why will become relevant after you read this article.

Sleep is something we mostly take for granted as part of our daily lives, much like eating and showering. But why do we sleep? What does sleep do for our minds and our bodies? What happens if we don’t sleep, or if we don’t sleep enough?

For those of you who are interested in these questions, I’d highly recommend that you read the transcript of The Science of Sleep, an excellent piece by 60 Minutes that aired on March 16, 2008. Not only did I learn many interesting facts about sleep, I learned about my own health and how sleep affects it. More on that later.

Why do we sleep? After all, from a survival point of view, sleep is not really a good thing, in the sense that we are unconscious and helpless during sleep. So for sleep to have evolved, then it must serve some vital functions. (I should point out though, that sleep might have survival advantages, since if early humans slept in caves and other sheltered places, sleep would have kept them out of the reaches of nocturnal predators. The folks who didn’t sleep much, and who wandered around all night, probably got eaten!)

One clue of how important sleep is in studies done in the 1980’s with rats. When rats were prevented from sleeping (did they use disco music to keep them awake?) they died after 5 days! Sleep seems to be as important to rats as food.

Let me present a quick primer on sleep. When we sleep, we actually go through multiple cycles of different stages of sleep. These stages are stages 1-4 of non REM (NREM) sleep, and stage 5 which is REM (rapid eye movement) sleep. The key stages are Stage 4, or Delta Sleep, and Stage 5, REM sleep. Stage 4 Delta sleep is the deep restorative sleep where our bodies get rebuilt and restored. Stage 5 REM sleep is when we dream, and it appears that our minds get restored during REM sleep. Typically the whole cycle takes about 100 minutes, and we have 3 or 4 of them each night.

Sleep may play an important role in enhancing memory. One study found that when people learned a new skill in the afternoon, and then were tested after a night of sleep, they did 20-30 percent better than those who were tested after twelve hours, but with no sleep in between the learning and testing. This is fascinating, and jibes with a trick I learned in graduate school. When I would study statistics, I’d always review my notes right before going to sleep. The next morning, the memories of those notes were imprinted magically in my mind.

Sleep also plays a critical role in stabilizing mood. One experiment tested people who were sleep deprived by showing them disturbing images within an fMRI scanner, to look at their brain activation. They found the sleep deprived subjects had a disconnect between the brain’s emotional center (the amygdala) and the part of the brain that controls rational thought (the frontal lobe). So they couldn’t control their emotional reactions. They looked more like psychiatric patients. Of course we all know that sleep deprivation makes us cranky and short-tempered, this explains why.

Another important function of sleep is physical rejuvenation. It appears that Stage 4 sleep is essential here. In the 60 Minutes piece they show an experiment where a young man named Jonathan is deprived of only Stage 4 sleep. Each time his brain waves show Stage 4 sleep, loud sounds are played to bring him out of deep sleep. He gets a normal amount of sleep, but a reduced amount of Stage 4 sleep. After 4 nights of this regimen, this 19 year old is starting to look physically like a 70 year old. His body becomes no longer able to metabolize sugar effectively, putting him temporarily at increased risk for Type 2 diabetes.

Other studies confirm this. After just a few nights of partial sleep deprivation, young healthy people show a metabolic change that is similar to what happens as people develop Type 2 diabetes. They no longer metabolize sugar effectively. They deposit more fat. The hormone leptin, which controls appetite, seems to drop, and they want to eat more.

This is truly astonishing. If relatively short term sleep deprivation can cause such a profound shift in the body’s sugar metabolism, then this may be the key to unlock one of the great medical mysteries of the 20th century: Why obesity has increased so rapidly since 1980? Could it be that the obesity epidemic is really a sleep deprivation epidemic? Could it be so simple? Not junk food, television, lack of exercise, and all of those things that people talk about? Could grandma have been right?

Here’s the clue.

In 1960 a survey of a million Americans showed an average of 8.0 hours of sleep per night. Today similar studies show we are only getting 6.7 hours a night. That’s a drop of 16.25% in less than a generation. And teenagers are the most sleep deprived of all, since they require 9-10 hours of sleep, and most get less than 7 hours of sleep, thanks to ridiculously early school start times. Teenagers may be lacking between 22 percent and 30 percent of their needed sleep.

So we have a plausible explanation for why everyone, even children and teenagers, is getting fatter. Sleep deprivation causes shifts in metabolism, creating a pre-diabetic state, and lowering level of the satiety hormone leptin, which causes us to eat more, and store more fat. Add sugary or high carbohydrate foods, and we get even fatter. Add inactivity, and we get even fatter. The damage begins early, perhaps in early teenage years.

So if we want to lose weight, then the old saw of a healthy diet and plenty of exercise may be wrong. The proper advice is probably lots of sleep, a reasonably healthy diet, and a little exercise. Or since exercise improves sleep quality, sleep, exercise, and diet. Without adequate sleep, diet and exercise are doomed to failure, since even young people may unintentionally be turning their bodies pre-diabetic, which makes it very hard not to gain fat.

So that’s why I haven’t written. After a lifetime of staying up late, and cheating sleep, I’m starting to try to get a solid 8 hours of sleep a night. Already I’ve lost a few pounds, even though I haven’t been exercising much. The other advantage of going to bed earlier is that when you are sleeping you are not eating.

So try it. Get 8 or 8 1/2 hours of sleep a night. And make sure your teenagers get 9 or 10 hours a night. No more websurfing or TV late at night. And write me and let me know if your weight drops as a result.

Now I’ve got to stop writing and go to sleep…

Copyright © 2008 The Psychology Lounge/TPL Productions

All Rights reserved (Any web links must credit this site, and must include a link back to this site.)

Protecting Your Brain (and Your Heart) With Fish Oil

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Protecting Your Brain (and Your Heart) With Fish Oil

Fish oil to protect brainA fascinating idea is how to protect your brain using simple nutrients. Can we protect our brains from depression, Alzheimer’s, even stroke using simple nutrients or over the counter supplements? I’ve written about the continuing search for predictors of Alzheimers here, but what if a simple nutrient could help prevent it? 

The Wall Street Journal just published an interesting article about using fish oil to treat or prevent a variety of illnesses. They even summarize the findings with recommended doses of fish oil. For instance, to prevent heart disease, they recommend one gram of EPA or more per day. For optimum brain health, take one-half gram of DHA or more. Even Rheumatoid arthritis may respond to 2 grams or more of fish oil.

Fish oil contains omega-3 fatty acids, of which there are two main ones; EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). Repeat after me if you want to really impress your physician: “eye-coh-sah-pent-ah-eh-no-ick  acid” and “doh-coh-sah-hex-ah-eh-no-ick acid”. Now you see why articles always say EPA and DHA!

There is a very interesting tie in with DHA and Alzheimer’s disease, as explained by an article on medicinenet.com.  It turns out that people with Alzheimer’s disease (AD) tend to have low levels of a brain protein called LR11, and about 15% of those with AD have a gene mutation that reduces LR11. LR11 works to clear the brain of amyloid proteins, which are implicated in the production of beta-amyloid plaque that clogs the neurons of those with AD.  Scientists tested DHA in rodents and in cultures of brain cells and found that DHA causes a higher production of LR11.

So should you be taking fish oil capsules, and how many, and which brand? I’d say if you eat oily fish like salmon 3 times a week or more, don’t worry about it. But for the rest of us (all of us?), it may make sense to add fish oil capsules to our vitamin regimen. A 1999 Italian study found that adding 3 capsules a day reduces the incidence of sudden cardiac death by 45%! The subjects in this study mostly also took baby aspirin, which may work to increase the effects of fish oil.

I’d certainly talk to your doctor about it. Be sure to print out the Wall Street Journal article, which demonstrates that there were few if any side effects. Some doctors think taking fish oil will make you bleed more easily, but studies of very high doses haven’t found this. In fact, the main side effect is belching fish smells, but I have found this is dependent on the brand and type of capsules you take.

Here’s a quick rundown on what to look for in fish oil capsules. First of all, they vary as to how much of the essential ingredients they contain. Most capsules contain 1 gram of oil, but much less Omega-3 fatty acids EPA and DHA. Some contain as little as 200mg. of the Omega-3’s, which means you have to eat a LOT of capsules to get much EPA or DHA. Often the bottles will mislead you by citing the amount per serving, and when you look more carefully you will see that one serving is 3 or 4 capsules!

So you want as high a concentration of EPA and DHA as possible. You also want fish oil that has been molecularly distilled to remove any possible contaminants such as pesticides, dioxin, etc.

Although I rarely make product recommendations, I heartily recommend Trader Joe’s Fish Oil capsules. Priced at $7.99 for a bottle of 100 capsules, these capsules are molecularly distilled and contain 300 mg. of EPA, and 200 mg. of DHA per capsule. That means that 2 capsules make up 1 gram of Omega-3’s.  So it is easy to take 1 or 2 grams of Omega-3’s per day, at an affordable cost. These compare favorably with much more expensive brands of omega-3 capsules.  Another trick is to store these in the refrigerator, so the oil doesn’t turn, and occasionally break open a capsule and smell it. Although it may have a slightly fishy smell, it should smell rancid or strong.

So there you have it, a simple way to reduce heart disease, autoimmune disease, and inflammation, and improve brain health. Cost? About $0.16  per day for 2 capsules.

As always, as I am not a physician, and certainly not your physician, talk to your doctor and do your own research before consuming more than a capsule a day of fish oil.

Copyright 2008 The Psychology Lounge/ TPL Productions 

All Rights reserved (Any web links must credit this site, and must include a link back to this site)

Scientists Try to Discover the Earliest Signs of Alzheimer’s disease (Is Alzheimer’s a Lifetime Genetic Disease?)

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Today’s New York Times has a fascinating article about current research in Alzheimer’s called Finding Alzheimer’s Before a Mind Fails. It is simultaneously encouraging and deeply disturbing.

The encouraging part is that researchers are discovering ways to examine patients that can find evidence of Alzheimer’s many years before the disease manifests itself in symptoms. A radioactive dye call Pittsburgh Compound B (PIB) is injected into the patient. This dye attaches itself to amyloid plaques in the brain, and then these can be seen by using a Positron Emission Tomography (PET) scan.  Studies using PIB have found the astonishing fact that amyloid plaques are found in 20-25 percent of people over 65 who appear normal! If the amyloid hypothesis is accurate, then many of these people will go on to develop Alzheimer’s disease.  Using PIB testing we could predict more accurately who will develop the disease, and perhaps develop prevention methods much like we give statins to heart patients who have plaques in their arteries. This is encouraging.

Someday in the future hopefully we will be tested for early signs of Alzheimer’s disease in our 40’s, and those who at risk given medications that will prevent it, just like we do for heart disease now. This would make aging much less scary.

Current Facts About Alzheimer’s disease

But the current facts about Alzheimer’s are less encouraging. It is the sixth more common cause of death by disease in the U.S. Five million people over 65 have Alzheimer’s disease. Estimates suggest that perhaps as many as 16 millions will have the disease by 2050, which is a staggering number that would bankrupt the health care system. (Of course, this assumes that in 43 years we have made no progress in the treatment and prevention of Alzheimer’s disease, which is absurd.)

Costs are already staggering–$148 billion dollars per year, and are increasing every year. Why? Here’s the dark truth. Alzheimer’s disease is a disease of the elderly. Almost 40 percent of those who live past 85 will eventually develop Alzheimer’s disease. The problem is that medical improvements are curing the diseases that used to kill us well before 85. One of the reasons Social Security starts at age 65 is that until recently, most people didn’t live much past the age of 65. Now as we defeat cancer and heart disease, and people stop killing themselves with diet and smoking, we are living into our 80’s and 90’s.  And getting Alzheimer’s disease.

What is Alzheimer’s disease?

Let’s talk a little more about what Alzheimer’s disease really is. Everyone worries about Alzheimer’s disease as they age. But some forgetfulness is completely normal. (We hope.) There is a old joke about Alzheimer’s disease which actually is a useful rule of thumb, it’s not a big deal if you forget where you put the car keys, as long as you can remember what keys are for. It is significant changes in memory and problem solving that are more worrisome.

When does Alzheimer’s disease begin?

This is a mystery currently. Conventional wisdom says that Alzheimer’s disease may begin a few years before symptoms appear, but some scientists question this. Because the brain has a lot of spare capacity, it may take years of deterioration before we lose enough brain function to notice. This may explain one of the common findings that the more highly educated (and probably more intelligent) develop Alzheimer’s disease as  a lower rate. They may have more spare capacity. If you start off with an IQ of 150, and lose a third of your brain functioning, you end up with an IQ of 100, and can still function. Start at IQ 100, lose 1/3, and you now are functionally retarded with an IQ of 66, and you won’t be able to live independently.

One scientist, Dr. Richard Mayeux, who is a professor at Columbia University, says, “I think there’s a very long phase where people aren’t themselves.”

“If Dr. Mayeux asks family members when a patient’s memory problem began, they almost always say it started a year and a half before. If he then asks when was the last time they thought the patient’s memory was perfectly normal, many reply that the patient never really had a great memory.” (New York Times)

This is interesting and disturbing stuff. Other research finds that people who later develop Alzheimer’s disease showed lower intelligence scores even early in life, suggesting that perhaps Alzheimer’s disease is a genetic disorder that affects the brain in subtle way even early in life. If this is true, then the data on highly educated people may have been interpreted in a backwards way—instead of higher education preventing Alzheimer’s disease, it may be that Alzheimer’s disease prevents higher education!

 

Treatment of Alzheimer’s disease

Currently there are drugs that address the symptoms of Alzheimer’s disease, but no drugs that address or slow the underlying disease progress. The good news is that there are numerous studies attempting to find drugs that will actually address the underlying disease process in Alzheimer’s disease. The bad news is that no one really knows exactly what that underlying disease process is.

There are two finding from examining the brains of those with Alzheimer’s disease. The first is that they show plaques of beta amyloid between the nerve cells of the brain. The second is that the brains show tangles inside nerve cells made of a protein called tau. This damaged tau kills the nerve cells because they no longer get nutrients.  Both these are well-established facts, but no one knows what is the relationship between beta amyloid and tau, and how much each contributes to Alzheimer’s disease.

 

What Society Should Do About Alzheimer’s disease?

So what can we as a society do about Alzheimer’s disease? My grandfather used to say, “Everyone dies, so it’s just a matter of how you die.” By choosing to treat or prevent heart disease and cancer, are we choosing to die from Alzheimer’s disease?   This is a scary thought.  It’s clearly worse to outlive your mind than to outlive your body. And Alzheimer’s disease puts huge burdens on society and caretakers. Maybe we should start a campaign to encourage cigarette smoking in the elderly! (Or motorcycle riding, but this might make the roads a bit dicey.) 

More seriously, we are in the unfortunate window of time where we have successfully improved longevity without really addressing this core disease of longer life, Alzheimer’s disease.  Society desperately needs to find an Alzheimer’s disease cure or preventative treatment. Without this we will as a society incur great costs and individual suffering. I believe that this should become a top priority of private and government research spending. First we need better basic research to find out what the disease process of Alzheimer’s disease looks like. Then we can develop effective drugs to block or reverse that disease process.

In the meantime, all we can do is not worry too much, since stress may damage the brain. Eat healthy, exercise, maybe take some anti-oxidant vitamins, and hope that science can solve this puzzle so we can get old without losing our brain function.   

As for me, I aspire to these not-so famous words of the comedian Will Shriner, “I want to die in my sleep like my grandfather… Not screaming and yelling like the passengers in his car.”

 

Copyright 2007 The Psychology Lounge/ TPL Productions, All Rights Reserved

The Physiological Mechanism for How Stress Affects the Brain

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For those readers curious about the mechanisms by which emotional stress affects brain function, I found an interesting piece of research about the physical mechanisms for how chronic stress can induce brain changes that could lead to cognitive impairment.

Scientists at Salk Institute for Biological Studies subjected mice to mild chronic stress for two weeks. What they found was fascinating. First some background on the physiology of Alzheimer’s disease. As the article explains:

“Alzheimer’s disease is defined by the accumulation of amyloid plaques and neurofibrillary tangles. While plaques accumulate outside of brain cells, tangles litter the inside of neurons. They consist of a modified form of the tau protein, which–in its unmodified form–helps to stabilize the intracellular network of microtubules. In Alzheimer’s disease, as well as various other neurodegenerative conditions, phosphate groups are attached to tau. As a result, tau looses its grip on the microtubules, and starts to collapse into insoluble protein fibers, which ultimately cause cell death.”

So basically, when phosphate attaches the the tau molecules, it causes them to change from helpful molecules to damaging the neurons.

The mice research found that the brain-damaging effects of negative emotions are relayed through the two known corticotropin-releasing factor receptors, CRFR1 and CRFR2, which are part of the body’s central stress mediation system.

So what does this all mean? It suggests that we have to protect our brains from stress, particularly chronic stress. Occasional stress doesn’t cause problems, but daily chronic stress does. The mice only showed permanent brain changes after 2 weeks of daily stress.

So stress management through cognitive behavioral therapy (CBT) or other means is not just a nice comfort option, but may be essential if you want your brain to last. Emotional pain doesn’t just cause emotional damage, it also damages the brain.

Perhaps scientists will be able to develop drugs that change CRF1 and CRF2 levels, but in the meantime, better take up that yoga, meditation, relaxation exercise, or CBT stress management program!

Copyright 2007 The Psychology Lounge/TPL Productions