People reach for sugar for reasons beyond habit and emotional eating; we as dietitians need to address this and help our clients to come up with healthier ways to lesson stress and bring down cortisol levels.
In the first study of its kind, published in the Journal of Clinical Endocrinology and Metabolism in April of 2015, researchers explained that sugar-sweetened beverages suppress the hormone cortisol and stress responses in the brain. The aspartame sweetened drinks did not alter hormone levels or brain responses. The parallel-arm, double-masked diet intervention study looked at the effects of sugar-sweetened and aspartame-sweetened beverages on 19 women between the ages of 18 and 40. Eight of the women consumed aspartame-sweetened drinks, while 11 were given the sugar-sweetened drinks; the drinks were consumed at all three meals for 12 days. After the 12-day study, the women had functional magnetic resonance imaging (MRI) screening and performed math tests; they also provided saliva samples to measure levels of cortisol.
Cortisol is a hormone released in response to fear or stress by the adrenal glands, and it is part of the fight-or-flight reaction. Cortisol is an adaptive hormone that is released whenever the body senses it is “in danger”; it raises blood glucose levels, raises blood pressure, and modulates immune function. If cortisol levels remain chronically high, it plays a part in the development of high blood pressure, prediabetes and diabetes, obesity, increased abdominal fat, decreased bone mass, brain changes, memory loss, depression, suicide, insomnia, and poor wound healing.
Cortisol levels can be high in people with Cushing’s syndrome, some types of cancer, long-term use of corticosteroids, severe liver or kidney disease, depression, hyperthyroidism, recent surgery, illness, injury, or sepsis.
Not only did the women who received the sugar-sweetened drinks have a diminished cortisol response to the math test, but they also had more activity in the hippocampus, which is the part of the brain involved in memory and that is sensitive to stress. The hippocampus is usually less active when the body is stressed.
It seems that we might reach for sugary foods when we are psychologically or emotionally stressed for physical reasons, rather than or in addition to the emotional reasons that we have always assumed. Considering that more than one in three adults and 17% of children are obese, this could be an important scientific finding. About half of all people consume sugar-sweetened drinks on a daily basis.
Sugar-free ways to get cortisol levels down:
References and recommended readings
Bergland, C. Cortisol: why “the stress hormone” is public enemy no. 1. https://www.psychologytoday.com/blog/the-athletes-way/201301/cortisol-why-the-stress-hormone-is-public-enemy-no-1. Accessed April 23, 2015.
Cortisol in blood. http://www.webmd.com/a-to-z-guides/cortisol-14668. Accessed April 23, 2015.
Gottfried, S. Cortisol switcheroo: how the main stress hormone makes you fat and angry. http://www.huffingtonpost.com/sara-gottfried-md/cortisol_b_1589670.html. Accessed April 23, 2015.
Matthew S. Tryon, Kimber L. Stanhope, Elissa S. Epel, Ashley E. Mason, Rashida Brown, Valentina Medici, Peter J. Havel, Kevin D. Laugero. Excessive Sugar Consumption May Be a Difficult Habit to Break: A View From the Brain and Body. The Journal of Clinical Endocrinology & Metabolism, 2015; jc.2014-4353
Svoboda, E. 8 ways to beat your stress hormone. http://www.prevention.com/mind-body/how-lower-cortisol-manage-stress Accessed April 23, 2015.
Contributed by Elaine M. Hinzey, RD, LDN
Review date: 4/23/15