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by Swee San Tan

Imagine that test week is approaching; you haven’t started your revision because lots of homework is due. Then, you also realize that this string of tests and homework goes on relentlessly until the term ends. Would you be extremely frustrated and worried? Would you reach for a bag of comfort food (such as French fries, potato chips, or cookies) in attempt to eat your stress away? After all, the word “stressed” spelt backwards is “desserts!” If this scene sounds familiar, you may be interested to know that there is a scientific basis to explain why you can effectively relieve your anxiety by consuming sweet and fatty comfort food. Although these foods take care of the stress, you could be gaining extra fat and getting a pound closer to the “Freshmen 15”—the notorious 15 pounds that many first-year college students gain. The good news is that scientific evidence shows that healthier alternatives (to potato chips) can help you to both reduce stress and avoid gaining too much weight.

 

How do comfort foods reduce stress?

            There is a biological reason to explain why college students binge on comfort food during test week. When you are chronically stressed, your adrenal gland produces glucocorticoids (GCs), a type of stress hormone that signals your body to seek out carbohydrate-laden food. Eating carbohydrates lowers the GC level in your body and lowers your stress response, making you feel better (Dallman et al, 2003).

The effects of GCs on stress response have been shown in a recent study by Dallman et al (2003). In their experiments, they used rats, which are surprisingly good models of human physiological processes. To simulate chronic stress, they increased rats’ brain concentration of cortisol (a rodent version of GC). As cortisol concentration increased, rats responded by drinking more sugar water, eating more lard, and gaining abdominal girth. This effect explains why you may unconsciously self medicate to reduce stress while doing an all-nighter, and may gain weight as a result.

Dallman et al’s study also found that GCs work differently in the long term than they do in the short term. If rats’ stress was prolonged, they kept eating and drinking. In another experiment, the same researchers found that fatter rats were less biologically responsive to stress than control rats. This suggests that you can eat more and gain weight to combat chronic stress because you are less likely to feel stressed if you are fatter. However, being fat is not your desired outcome!

 

What healthier stress-relieving foods exist?

            Since students tend to prefer eating food that can be purchased on their way to class, it is highly likely that they would rather grab a hamburger made ten minutes ago than stand in line for a turkey sandwich (no mayo). However, there are some healthier stress-relieving alternatives to fast food that are just as convenient.

Oranges, for example, are obviously healthier than French fries, but researchers have also discovered that the Vitamin C in citrus fruits acts as a stress busting antioxidant. Campbell et al (1999) show that Vitamin C lowers the level of stress hormone in laboratory rats. Stressed rats that received a daily dose of 200mg of Vitamin C showed lower blood concentrations of stress hormone than rats that received no Vitamin C. This suggests that you can try to consume citrus fruits or take Vitamin C tablet supplements to relieve stress.

Furthermore, a study by Markus et al (2000) found that stress-prone individuals might cope with pressure better if they tailored their diet to fuel the brain with tryptophan. It is used by the brain as a building block of serotonin, a hormone that relaxes people. Markus et al’s investigations required subjects to fast overnight. Then they each had either a chocolate drink laced with a low concentration of tryptophan or another that had a higher concentration of tryptophan, for both breakfast and lunch. After lunchtime, against a backdrop of loud industrial noise, each volunteer spent 20 minutes at a computer screen calculating math sums. Markus et al noted that volunteers’ level of brain serotonin dropped and they felt stressed after being given the tryptophan-low drink. On the other hand, these volunteers showed increased brain serotonin levels and they did not feel as stressed after consuming the tryptophan-rich drink. Since these results show that trypotophan may replenish the serotonin that chronic stress depletes, you could eat more tryptophan-rich foods like turkey, cashews, soy beans or tuna to reduce your stress level. Also, tryptophan produces serotonin only when your stomach is empty so you can consider snacking on a piece of turkey while working late at night.

Another way to relieve stress is to eat healthy carbohydrates. A study done by Wurtman et al (2003) showed that carbohydrates increase the plasma concentrations of tryptophan, which in turn increases the amount of serotonin produced, causing the person to be more relaxed.  You could try to include high-fiber, carbohydrate-rich foods such as baked sweet potatoes, minestrone soup or sautéed vegetables over rice. Healthy carbohydrates are alternatives to fat-laden carbohydrates such as potato chips, although they may not be as convenient.

 

Eat right to avoid succumbing to the “Freshmen 15”

You probably already knew that eating a bag of potato chips while studying can help you feel more relaxed, but now you know that there also exist less fattening and equally effective stress-reducing alternatives. Certainly it takes lots of determination to eat right and reduce stress, but once this is achieved, you may well be on your way to a “Freshmen 15”-free college life.

 

 

Bibliography

Dallman, M.F. Pecoraro, N. Akana, S.F. la Fleur, S.E. Gomez, F. Houshyar, H. Bell, M.E. Bhatnagar, S. Laugero, K.D. and Manalo, S.2003. “Chronic stress and obesity: A new view of “comfort food””, Proceedings of the National Academy of Sciences, 100 (20), 11696-11701. http://www.pnas.org/cgi/content/full/100/20/11696. Last accessed: 19th February 2004.

 

Markus, C.R. Olivier,B. Panhuysen, G.EM. Van der Gugten, J. Alles, M.S. Tuiten,A. Westernberg, H.GM. Fekkes, D. Koppeschaar, H.F. and de Hann, EEHF. 2000. “The bovine protein alpha-lactalbumin increases the plasma ratio of tryptophan to the other large neutral amino acids, and in vulnerable subjects raises brain serotonin activity, reduces cortisol concentration, and improves mood under stress”,  The American Journal of Clinical Nutrition, 71(6), 1536-1544. http://www.ajcn.org/cgi/content/full/71/6/1536. Last accessed: 19th February 2004.

 

O’Keefe, M.P.  Scholz, C. and Campbell, P.S. 1999. “Vitamin C attenuates the physiological response to stress.” Book of Abstracts, 218th American Chemical Society National Meeting. 1999, 79. http://www.designinglogic.com/upload/www.aor.ca/MedicalAbsDetail.asp?abs_id=98 Last accessed: 19th February 2004.

 

Wurtman, R.J. Wurtman, J.J. Regan, M.M. McDermott, J.M. Tsay, R.H. and Breu, J.J. 2003. “Effects of normal meals rich in carbohydrates or proteins on plasma tryptophan and tyrosine ratios”, The American Journal of Clinical Nutrition, 77(1), 128-132. http://www.ajcn.org/cgi/content/full/77/1/128 Last accessed: 19th February 2004.

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