Stress, eating, and the college student

by Stephanie Scott

Twinkie by nataliej

Stressful situations cause the production of cortisol, a stress hormone.  This hormone causes an increased heart rate, diversion of blood flow to muscles, and metabolic changes, which allows energy to be made ready for use by the muscles.  All of these responses aim to aid in survival in stressful, and possibly life-threatening, situations.  This mechanism works through a negative feedback system, so the stress response is able to quickly shut itself off and allow the body to function normally again.

Generally, this is not the type of stress that college students deal with in their lives. With ever-increasing demands from classes, the responsibility of being on one’s own, possible financial responsibilities, lack of sleep, substance abuse (or decisions about whether to take part in such activity), and trying to figure out how to balance everything, stress levels are often elevated in college students. If students do not learn to manage their busy lives, it can lead to chronic stress.

Chronic stress affects the body using the same mechanism as a regular stress response.  However, chronic stress causes the body to produce cortisol in a routine manner to allow the body to physiologically respond to the stressful situations it is placed in, and these stress responses do not shut themselves off using a negative feedback system. When a response that requires much energy does not shut off, it quickly depletes the body’s energy supply.  This can lead to food cravings– especially cravings for high-energy foods containing much sugar and fat.  These foods are favorable because they tend to be deposited as fat in the abdomen, and abdominal fat is easily accessible by the liver to be used for energy.  Also, these abdominal fat deposits send out metabolic signals that turn off the stress response in the body. Therefore, eating high-energy foods is important when dealing with chronic stress because it allows the body to gain energy deposits so the body can function once previously stored fat deposits have been depleted by energy-consuming stress responses.

Alzheimer’s, sleep and copper

by Robert Rooney and Jesse Greenberg*

Alzheimer's disease brain (note the enlarged ventricles, or holes in the middle)

Named after German physician Alois Alzheimer, Alzheimer’s disease is a terminal brain disorder that gets progressively worse over time.  Alzheimer’s deteriorates and destroys brain cells, causing detrimental effects to memory, behavior and one’s thought process.  A main characteristic of Alzheimer’s is the extensive development of “plaques and tangles.”  Plaques are deposits of the protein beta-amyloid that accumulate in the spaces between nerve cells.  Tangles are deposits of the protein tau that accumulate inside of nerve cells.  Although most people develop some plaques and tangles over time, those diagnosed with Alzheimer’s tend to have a much larger build up of these proteins.  The plaques and tangles are thought to impede interaction between nerve cells and interrupt cell activities necessary for survival.

Scientists are still not sure what exactly causes Alzheimer’s, but current research and evidence point to a few key risk factors.  These factors include, but are not limited to, aging, heart disease, head injury, and genetic history.  While lack of sleep is not considered a risk factor, recent studies suggest it may play a role.

One study performed by members of the Department of Neurology at Washington University, St. Louis showed that plaque levels increased significantly in mice when they were deprived of sleep.  They also found a correlation between beta-amyloid levels and sleeplessness.  The research team also studied a group of male volunteers and found similar correlations.  They found increased levels of beta-amyloid during the time while the men were awake, with the highest peak level around the evening, but the protein levels decreased when the men slept.  Due to the similarities between the results of the mice and the men, the researchers concluded that optimization of sleep time could potentially reduce aggregation of the beta-amyloid protein and slow the progression of AD.

Meanwhile, copper has also been getting a lot of attention from Alzheimer’s researchers.  Over the past decade, the role of copper in Alzheimer’s disease has also been extensively explored, yet two conclusions are being drawn which only serve to cloud our understanding.  The continuing exploration of the interesting relationship between copper and Alzheimer’s disease will hopefully yield an important breakthrough in the near future.

Brave new tastes

By Dorie Obertello

No one will deny that America, as a country, is overweight. Some states have obesity rates that surpass 1 in every 4. There are countless theories as to why this is the case. Is it socioeconomic? Cultural? Medical?

A study by Don Katz from Brandeis University about taste got me thinking not about why American is fat, but how we could fix it. It does not seem that Katz has looked at the weight loss angle of his research, but I see a very possible link.

A popular remedy to excess weight, other than diet and exercise (which for some is too gradual or ineffective) is surgery. This seems a bit extreme because while it is effective, it is also incredibly dangerous. There must be a better way to return quickly and permanently to normal weight.

Katz is studying the links between tastes and emotions. He has postulated that every taste, without exception, invokes a tangible response, usually in the form of brain activity. However, many tastes also evoke emotions, often mirror images of feelings about the setting and/or experience of past consumption.

He has found that if a taste is associated with a negative experience and negative emotions, the taste itself will become disliked. This is called taste aversion. It holds true for a number of animals, from humans to mice (Katz is currently using mice).

So, what if doctors and scientists could program obese patients to loath unhealthy foods? The idea is not extraordinary. All that would be necessary is a bad experience to accompany the taste. If French fires and fried chicken seem vile due to a particularly nasty past stomachache, there is little risk an overweight individual will want to eat them.

Taking the idea a step further, perhaps children could be taught preemptively to dislike certain fattening or non-nutritious foods in an effort to stem the growing “epidemic,” as some call it. Of course, this preventative measure is not right for everyone. However, for those at risk, a picky palette is better than a lifetime of health trouble.

Blueberries, tea, chocolate, memory and skepticism

If you read newspaper and internet stories about foods and health, you have no doubt come across articles touting the memory boosting properties of certain foods, like blueberries. Even on this site, a number of posts have touted the memory-boosting properties of certain foods:

• A substance, epicatechin , found in chocolate, has been shown to improve spatial memory. Specifically, it boosted the ability of rats to remember the location of a platform in a murky pool of water. This worked better when the rats were getting regular exercise.
• Another chemical, theanine, found in tea, has been found to boost attention skills, when used in conjunction with caffeine (also found in tea). Human participants were better at picking out a target on a computer screen when their pre-game water had been spiked with the caffeine/theanine combination.

But should you really be scarfing down blueberries, tea and chocolate when you study? Well, maybe, because they all taste good, though the chocolate might make you gain weight, and the tea might keep you awake. But we don’t really know if they will be of any use in the kind of memory involved in studying for school. We don’t know that because we have not seen the research. It is tempting, but foolish, to assume that our brains will respond in much the same way as rat brains, or that success on laboratory tasks will translate to success in real-world tasks. In fact our brains are different in some important ways from rats’ brains (a bigger ratio of cortex to brain, for example) and not all memories are the same (semantic memory, the stuff you know, involves different parts of the brain than procedural memories, what you know how to do).

So where is the real-world, human subjects research? It is quite possible it is sitting in a file-drawer somewhere. It is notoriously difficult to publish studies which show no effect. Perhaps some reputable scientist has actually done research on the effects of chocolate or tea on memory for texts, for example, and found no effect. It would not be easy to get that research into a journal, let alone on to WebMD or USA Today.

Or perhaps the research just hasn’t been done. For reasons I have difficulty fathoming, many scientists, including journal editors, may be more interested in carefully controlled studies using extracts of chocolate on rats doing laboratory memory tasks. It just sounds so much more scientific than the relatively simple experiment of testing tea or chocolate on actual people studying.

Meanwhile, I see no harm in boosting your consumption of blueberries, or replacing other fattening foods with chocolate, or replacing coffee with tea. And who knows, you may someday find yourself swimming in murky water and be glad you did.

Can food be an addiction?

by Rachel Harris

Many addictive drugs, such as nicotine, alcohol, and amphetamines, change the levels of dopamine in an area of the midbrain called the substantia nigra. In disrupting the dopamine systems in the brains, these drugs interrupt the brain’s quest for rewards and control of decisions. Recently, the obesity epidemic has catalyzed many psychologists to examine how food consumption acts on the brain in ways similar to substances more typically associated with addiction. Researchers at the National Institute on Drug Abuse have compared brain images of obese people and methamphetamine users. They have found that fewer dopamine receptors in both groups, when compared to a normal control group. Moreover, the signs of drug addiction‹: developing tolerance, withdrawal symptoms, and overwhelming involvement‹ are also seen with food. [Editor's note: More on food "addiction" in this post on the hazards of delicious food. ] In addition, the absence of food is seen to cause withdrawal symptoms in rats. Although these results cannot be directly applied to humans, this study suggests that food might create powerful motivations to eat not only because the taste is rewarding, but also because eating reduces anxiety or stress.

More on the “freshman 15″

It is, without a doubt, difficult for most students to adjust to college life. Many students are far from home, and often for the first time. There are a myriad sources of stress and lifestyle changes that no amount of warning can really prepare for. There are new classes that are significantly more intense than their high school equivalents, there is an entirely new work load, and there is the pressure to do well and prove one’s self. But even more difficult to deal with than academic pressure is the entirely new social network that evolves. Freshman are, for the most part, paired with a roommate they have never before met, and more than likely have very little in common with. Students also have to make new friends, and develop new social habits. There is also the added freedom of alcohol and drugs found on most college campuses which can lead to difficult (and dangerous) decisions. All in all, it is no wonder that the freshman experience so often includes weight gain, or “the freshman fifteen.”

A post everyone can agree with

by Andrea Lam

When I was in middle school, my teachers would sometimes have us vote–by a show of hands–on what we thought was the answer to a problem. At times we’d vote with our heads up and our eyes open, and at other times we’d vote with our heads down on our desks and our eyes closed. When we voted with our eyes closed, I personally always felt a little silly, sitting at my desk with my books in front of me, my eyes squinched shut and my hand in the air, but I never felt any pressure to pick an answer besides the one upon which I had decided. This method of voting was anonymous–or at least as anonymous as it got in sixth grade. But it was an entirely different story when we voted with our eyes open. Then we could see each other, and thus see who picked what answer. Often a just a few hands would go up at first, then a few more, and after a furtive look or two, even more. I remember on more than one occasion looking around the room and, after seeing many of my fellow classmates raising their hands with apparent confidence in the truth of their decision, changing my mind and raising my hand as well. I didn’t want to get labeled as the kid who voted the wrong way, because everyone else must have been right–right?

A recent article in The New York Times deals with this issue of peer- (or authority-) pressure-induced decision-making. Titled Diet and Fat: A Severe Case of Mistaken Consensus, it deals with the idea of “informational cascades” and how they affect even the most intelligent groups of people. An informational cascade is basically what happens when one or two people publically guess one way and everyone else follows, each one “[assuming] that the rest can’t all be wrong.” Because of this tendency, many people who originally believed the “other” way will generally change their minds, even if the group’s final “decision” ends up being incorrect.

Boosting your memory with yummy foods

Have you ever wished that you could be thrown repeatedly into a swimming pool filled with murky water, and reliably find your way to a submerged platform? Probably not. But that is a common way to test the memory of  mice. Mice who remember the location of the platform find it more quickly, and of course mice with better memories remember the location better. But what makes for a good memory in a mouse? Surprisingly, one of the answers is a group of foods that contains the antioxidant chemical epicatechin. A recent study in the Journal of Neuroscience found that mice who ate more of this chemical found the submerged platform more quickly than a control group of rats who did not get an epicatechin supplement.

So where can you get epicatechin? In some very tasty foods, actually. Blueberries, grapes, tea, and cocoa top the list. Personally, I like the prospect of eating more dark chocolate and drinking more tea. But the study suggests there is one more step I should take, to get maximum benefit to my memory: Exercise. Rats that ran a treadmill for two hours a day, and also go the epicatechin supplement had the best performance in the underwater maze. I hate treadmills, but if raking leaves or walking my dogs can work as a substitute, I’m already there.

Of course, there may be a few nit-pickers out there who will point out that mice are not exactly the same as people, and that finding a submerged maze may not involve the same memory systems as remembering material for a psychology quiz. Pick all you want, but you are not going to stop me from making a batch of blueberry muffins, and telling myself that they are good for me.

The hazards of delicious food

 by Amielle Major

It seems like something we already know: Overeating or even eating “high calorie” foods is more than a simple homeostatic (eating because of physical need) process. However, Dr. Michael Lowe, Drexel University professor of Psychology, and other researchers closely observed existing food intake studies and found correlations that would suggest we have a drive for eating that is similar to those produced by other pleasure driven activities like drug use.  The researchers found that delicious food can make you want to eat it more frequently and that it’s even worse if in your environment the food is easily accessible.

Serving up food research with a big spoon

by Jasmin Iskandar

When it comes to matters of pleasure and guilt, there is no more prominent locus for the juxtaposition of these things than food. American society has adopted food as a tradition that exercises social functions as well as it makes us feel joy and occupies our thoughts. These days, Americans can qualify themselves into two orders of consideration with regards to eating—there are those who eat freely, devoid of any guilt, and there are those who obsess over their food.   For those who are less occupied with their habits of consumption, Cornell researcher Brian Wansink offers some interesting information about why some Americans should be more wary of what it is that we are eating.  A recent article in Time Magazine profiles his research.