High-fat Diet Disrupts Body Clock

roster · Post by **roster** » Sat Jan 19, 2008 5:49 pm

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High-fat Diet Disrupts Body Clock

ScienceDaily (Nov. 7, 2007) — Our body's 24-hour internal clock, or circadian clock, regulates the time we go to sleep, wake up and become hungry as well as the daily rhythms of many metabolic functions. The clock -- an ancient molecular machine found in organisms large and small, simple and complex -- properly aligns one's physiology with one's environment.

Now, for the first time, a Northwestern University and Evanston Northwestern Healthcare (ENH) study has shown that overeating alters the core mechanism of the body clock, throwing off the timing of internal signals, including appetite control, critical for good health. Animals on a high-fat diet gained weight and suddenly exhibited a disruption in their circadian clocks, eating extra calories during the time they should have been asleep or at rest.

The study, which will be published in the Nov. 7 issue of the journal Cell Metabolism, also shows that changes in metabolic state associated with obesity and diabetes not only affects the circadian rhythms of behavior but also of physiology. Probing beyond the behavioral level, the researchers observed actual changes in genes that encode the clock in the brain and in peripheral tissues (such as fat), resulting in diminished expression of those genes.

These findings close an important loop in studies led by Joe Bass, M.D., assistant professor of medicine and neurobiology and physiology at Northwestern and head of the division of endocrinology and metabolism at ENH, of the relationship between the body clock and metabolism. Two years ago Bass and his colleagues reported in the journal Science that a faulty or misaligned body clock can wreak havoc on the body and its metabolism, increasing the propensity for obesity and diabetes.

Since then, knowing that genetic mutations rarely are the reason for a malfunctioning body clock, Bass has been wondering what could upset the operation of this internal timing device. What are the environmental factors or common influences that might affect the clock and in turn disrupt the sleep/wake cycle"

"Our study was simple -- to determine if food itself can alter the clock," said Bass, senior author of the paper. "The answer is yes, alterations in feeding affect timing. We found that as an animal on a high-fat diet gains weight it eats at the inappropriate time for its sleep/wake cycle -- all of the excess calories are consumed when the animal should be resting. For a human, that would be like raiding the refrigerator in the middle of the night and binging on junk food."

The clock-metabolism cycles feed on each other, creating a vicious loop, says Bass. Once weight gain starts, the clock is disrupted, and a disrupted clock exacerbates the original problem, affecting metabolism negatively and increasing the propensity for obesity and diabetes.

"Timing and metabolism evolved together and are almost a conjoined system," said Bass. "If we perturb the delicate balance between the two, we see deleterious effects."

The biological clock is central to behavior and tissue physiology. Clocks function in the brain as well as lung, liver, heart and skeletal muscles. They operate on a 24-hour, circadian (Latin for "about a day") cycle that governs functions like sleeping and waking, rest and activity, fluid balance, body temperature, cardiac output, oxygen consumption and endocrine gland secretion.

In their study, Bass and his team studied mice with the same genetic backgrounds. After feeding them a regular diet for two weeks, they were split into two groups for the remaining six weeks, one kept on a regular diet and the other fed a high-fat diet. After two weeks, those on the high-fat diet showed a spontaneous shift in their normal pattern of activity/eating and resting/sleeping. They began to eat during their typical rest or sleep period (daylight for a mouse). The animals on a regular diet did not exhibit this behavior.

"It's not just that the animals are eating more at regular meals," said Bass. "What's happened is that they actually shift their eating habits so that all excess food intake occurs during their normal rest period."

In the study's high-calorie, high-fat diet, 45 percent of calories was contributed by fat. For humans, a diet with no more than 30 percent of calories from fat is recommended.

The entire study was conducted in darkness so that the behavior of the animals simply reflected their internal clock; a normal animal has a very fixed daily period of just less than 24 hours. For animals on a high-fat diet, after two weeks on that diet the animals' behavior changed: their daily period of sleep/wake was lengthened by a significant amount. This suggests, says Bass, that the central mechanism in the brain that controls the timing of the cycle of activity and rest is affected by a high-fat diet.

"Our findings have implications for human disease," said Bass. "These basic advances in science can be applied to the studies of common disorders like obesity and diabetes. It is important to understand what happens when diet changes."

In addition to Bass, other authors of the paper, titled "High-Fat Diet Disrupts Behavioral and Molecular Circadian Rhythms in Mice," are Akira Kohsaka, of Northwestern (lead author); Aaron Laposky, research assistant professor at Northwestern's Center for Sleep and Circadian Biology; Kathryn Moynihan Ramsey, Carmela Estrada and Corrine Joshu, of Northwestern; Yumiko Kobayashi, of Evanston Northwestern Healthcare; and Fred W. Turek, professor of neurobiology and physiology at Northwestern and director of the Center for Sleep and Circadian Biology.

The work was supported by the National Institutes of Health and Amylin-Eli Lilly Ventures Pharmaceuticals.

Adapted from materials provided by Northwestern University, via EurekAlert!, a service of AAAS.

Northwestern University (2007, November 7). High-fat Diet Disrupts Body Clock. ScienceDaily. Retrieved January 19, 2008, from http://www.sciencedaily.com /releases/2007/11/071106133111.htm

GrizzlyBear · Post by **GrizzlyBear** » Sat Jan 19, 2008 6:20 pm

There's some very thought-provoking stuff in this article.

In my country, there have been proposals to make lap band surgery (where a band is placed on the stomach to control food intake) more freely available to help control what is perceived to be an obesity epidemic. The consequences of obesity are many and varied.

There is quite an argument going on here - particularly between those who believe obesity is self-generated, so sufferers should bear the consequences, (and we make an effort to exercise and pay for exercise equipment, why should they get something for nothing) and those who are looking for quick-fix solutions.

Regards,

GrizzlyBear

Daffney_Gillfin · Post by **Daffney_Gillfin** » Sat Jan 19, 2008 6:52 pm

I can only speak for myself, but first, my high-fat diet (60% calories from fat) has not caused weight gain, The exact opposite, in fact. Secondly, I'm sleeping fine. I still sleep the same hours that I slept before. I still don't get up during the night and eat. I guess one difference may be that I'm not having to force myself to stay up past 7pm anymore, as I often had to do before the diet change. And that was even after the xPAP.

They don't mention it here, but I've read that it was a 12 minute shift. Given that I don't live in 24 hours of darkness, I'll stick to what is working for me.

roster · Post by **roster** » Sat Jan 19, 2008 7:03 pm

Daffney_Gillfin wrote:I can only speak for myself, but first, my high-fat diet (60% calories from fat) has not caused weight gain, The exact opposite, in fact. .....

A good many years ago I read "The Zone" by Dr. Sears. He cites some studies that show people losing weight on a high fat diet.

My own is experience is no weight gain with a high fat diet. But a high carbohydrate diet will cause me to gain weight.

Just curious Daffney, which fats are you consuming?

Daffney_Gillfin · Post by **Daffney_Gillfin** » Sun Jan 20, 2008 7:02 am

rooster wrote:
Just curious Daffney, which fats are you consuming?

Pretty much all of them except trans fat and vegetable oil. I recently picked up some coconut oil, and that is now my fat of choice for cooking, and skin care. I mix it with bacon grease for taste, because I got the extra virgin coconut, and it's a bit strong on the taste. I am getting used to it though. I take fish oil supplements - 4-6g a day. I use ground flax seed in salads and smoothies. I'm trying to figure out how to use them more often. Olive oil for sauteing some things, depending on the meal, and sometimes on salad when I'm looking for extra fat or trying to use up my EVOO. And butter, never margarine or any other kind of fake butter-like spread.

I eat all kinds of meat, but mostly beef. Probably because that's what I'm used to cooking. We always had a side of beef in the freezer when I was growing up like all rural Kansas families. I throw in fish a couple times a week. Lots of chicken dark meat. Bacon or sausage daily for breakfast with eggs, but rarely any other pork. I don't drink milk, but do use cream and cheese.

I think that covers all the fat.....

I am currently reading Gary Taubes' new book. I doubt I'll ever go back to a LFHC diet after that. A very good read. I highly recommend it.

Daffney_Gillfin · Post by **Daffney_Gillfin** » Sun Jan 20, 2008 7:08 am

Daffney_Gillfin wrote:
I think that covers all the fat.....

I forgot the nut butters and oil. And just nuts -- walnuts, almonds, pecans. Sometimes a deluxe nut mix. I found that I don't have good moderation skills with nut products, so I don't keep them around as much as I have in the past.

roster · Post by **roster** » Sun Jan 20, 2008 7:56 am

We like a lot of the same things. I would add to your list chocolate milkshakes, banana splits and Dairy Queen's mud pie Blizzards.

I never bought coconut oil because it was preached to me years ago that it is high in saturated fat and should be avoided. ???

DreamStalker · Post by **DreamStalker** » Sun Jan 20, 2008 8:04 am

Daffney_Gillfin wrote:
rooster wrote:
Just curious Daffney, which fats are you consuming?
Pretty much all of them except trans fat and vegetable oil. I recently picked up some coconut oil, and that is now my fat of choice for cooking, and skin care. I mix it with bacon grease for taste, because I got the extra virgin coconut, and it's a bit strong on the taste. I am getting used to it though. I take fish oil supplements - 4-6g a day. I use ground flax seed in salads and smoothies. I'm trying to figure out how to use them more often. Olive oil for sauteing some things, depending on the meal, and sometimes on salad when I'm looking for extra fat or trying to use up my EVOO. And butter, never margarine or any other kind of fake butter-like spread.

I eat all kinds of meat, but mostly beef. Probably because that's what I'm used to cooking. We always had a side of beef in the freezer when I was growing up like all rural Kansas families. I throw in fish a couple times a week. Lots of chicken dark meat. Bacon or sausage daily for breakfast with eggs, but rarely any other pork. I don't drink milk, but do use cream and cheese.

I think that covers all the fat.....

I am currently reading Gary Taubes' new book. I doubt I'll ever go back to a LFHC diet after that. A very good read. I highly recommend it.

Sounds like Atkins on steroids

I think everyone responds to different foods differently.

The types of food that do seem to be unhealthy for most are trans-fats and highly refined/processed carbs. In addition, it is still the balance of calories in and calories out with regard to weight control.

On "animal" fats, it is important to realize that toxins tend to accumulate in fat cells ... so as long as the source and living conditions of the consumable animal(s) is known to be safe ...moderation of these types of caloric intake is the principle consideration (fats have twice caloric value of carbs or proteins). There are also vitamin and mineral considerations to consider when excluding the plant kingdom

Pilot_Ron · Post by **Pilot_Ron** » Sun Jan 20, 2008 9:02 am

I'm hoping that with my case, that my OSA has been a contributing factor to my weight. I eat 3 meals a day, but not neccessarily in excess. I'll be the first to admit, that my portion sizes are a little bigger that they should be sometimes, however I don't get rediculous. I don't eat sweets, or junk food. No desert, and no snacks in between meals. The food that I eat, although not considered health food, is not junk food either. I eat plenty of vegetables, and stay away from sugar loaded drinks. I walk about 2 miles a day, and in the spring and summer I will walk 18 holes of golf sometimes 2 times over a weekend. I ride my bike with my daughter about 3 miles at a time. (all this with an AHI of >60 and SP O2 <85% during Apneas in REM sleep) I was one of the keep moving or die mentallity, but since starting PAP have found a whole new level of energy, although I have cold now, I continue to find extra energy reserves. I have recently had complete blood work done, and there are no issues with my body that I, or my GP can see which would contribute to metobolic issues. So I cross my fingers that the PAP is a key factor, because my Circadian Rhythm seems to bee keeping a fine beat.

roster · Post by **roster** » Sun Jan 20, 2008 9:14 am

Pilot_Ron,

That sounds like a very nice success story in the making. Keep at it!

Always willing to give advice where none is asked for, I will suggest two things. Add a little bit of resistance training three times per week. Also, a good breakfast is very important to weight loss, witness that old saying, "For health, eat the breakfast of a king, the lunch of a prince, and the dinner of a pauper."

Rooster

Daffney_Gillfin · Post by **Daffney_Gillfin** » Sun Jan 20, 2008 12:52 pm

DreamStalker wrote:Sounds like Atkins on steroids

Basically, it's Atkins/Protein Power. I didn't really bother with induction. I don't count calories, and I don't really even count carbs. I eat low-carb healthful foods, and it seems to take care of it. The weight is coming off.

DreamStalker wrote: I think everyone responds to different foods differently.

The types of food that do seem to be unhealthy for most are trans-fats and highly refined/processed carbs. In addition, it is still the balance of calories in and calories out with regard to weight control.

However, I can eat more calories if I leave out the carbs and still lose weight. Many people can. Without the extra carbs, there's not as much insulin pushing fat into the fat cells. It's a matter of how your body reacts to what you eat, which like you said is going to be different per person.

DreamStalker wrote:
On "animal" fats, it is important to realize that toxins tend to accumulate in fat cells ... so as long as the source and living conditions of the consumable animal(s) is known to be safe ...moderation of these types of caloric intake is the principle consideration (fats have twice caloric value of carbs or proteins). There are also vitamin and mineral considerations to consider when excluding the plant kingdom

Sure, I get range fed/hormone free/organic/etc when I can get it. I don't stress over it though. Don't need to be raising my cortisol levels. So what if fat has twice the caloric value of carbs and protiens? Fat and protiens fill me up. They don't induce an insulin release. I stay satisfied for hours. Throw in a bunch of carbs, and I'll be hungry an hour later. While I never said I excluded the plant kingdom (I only mentioned my fat sources), there's no such thing as an essential carb. I eat vegetables for variety, and I like 'em. I probably eat more vegetables than the average American. (I know that's not saying much.) Grains, I can do without. I don't see a reason to be eating them.

Daffney_Gillfin · Post by **Daffney_Gillfin** » Sun Jan 20, 2008 2:37 pm

rooster wrote:We like a lot of the same things. I would add to your list chocolate milkshakes, banana splits and Dairy Queen's mud pie Blizzards.

I never bought coconut oil because it was preached to me years ago that it is high in saturated fat and should be avoided. ???

I love the Dairy Queen stuff, too. However, I just have to face the fact that I'm better off in every way without them. I have no acceptable limits when it comes to the cold tasty treats. I no longer have the cravings for them. But then it is winter yet.

When coconut oil was demonized by the government, the oil that was being discussed was the hydrogenated or partially hydrogenated oil. Virgin coconut, or even refined, bleached and deodorized, is OK. It is a medium chain triglyceride, and processed differently by the body from the more common long chain triglycerides.

There is much information on the Internet. Bruce Fife seems to be the coconut oil guru. Also, see Mary Enig.

roster · Post by **roster** » Sun Jan 20, 2008 7:08 pm

Daffney_Gillfin wrote:.......

When coconut oil was demonized by the government, the oil that was being discussed was the hydrogenated or partially hydrogenated oil. Virgin coconut, or even refined, bleached and deodorized, is OK. It is a medium chain triglyceride, and processed differently by the body from the more common long chain triglycerides.

There is much information on the Internet. Bruce Fife seems to be the coconut oil guru. Also, see Mary Enig.

OK, you are teaching me something. I used to love raw coconut but stopped eating it after the popular press jumped on coconut oil 15 or 20 years ago.

I found this from Bruce Fife:

"Once mistakenly believed to be unhealthy because of its high saturated fat content, it is now known that the fat in coconut oil is a unique and different from most all other fats and possesses many health giving properties. It is now gaining long overdue recognition as a nutritious health food.Coconut oil has been described as "the healthiest oil on earth."

DreamStalker · Post by **DreamStalker** » Sun Jan 20, 2008 10:46 pm

Daffney_Gillfin wrote:
Basically, it's Atkins/Protein Power. I didn't really bother with induction. I don't count calories, and I don't really even count carbs. I eat low-carb healthful foods, and it seems to take care of it. The weight is coming off.

Congrats on the weight loss!

I just ordered Taubes' new book from Amazon to add to my growing collection of food/diet related info ... thanks for the heads up

Daffney_Gillfin · Post by **Daffney_Gillfin** » Mon Jan 21, 2008 5:56 am

DreamStalker wrote:
Congrats on the weight loss!

I just ordered Taubes' new book from Amazon to add to my growing collection of food/diet related info ... thanks for the heads up

Thanks!

I hope you noticed that it's not really a diet book in the the sense it will tell you what to eat and not to eat. It's more about diet research, politics, and how we got to where we're at today in diet recommendations. It can be dry, and I admit much of it went over my head. I end up reading some pages more than once, and have even gone back to re-read entire sections. I plan to re-read the entire book after I finish it. Probably not right away though. It's a lot like reading Lyle McDonald's first ketogenic diet book, but with more history. If you read the reviews on Amazon with low ratings, then you probably already know this.

Humidifier

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