ergo-log.com

Definition: "An ergogenic aid is any substance or phenomenon that enhances performance "

26.04.2017

Increased cortisol levels from chronic stress make you fat

We don't need to tell our regular readers that cortisol, the hormone that's released when we're under stress, can have a disastrous effect on your body. The epidemiological study that British researchers published in Obesity confirms this yet again. The Brits were able to show that a chronically raised cortisol level dramatically increases the chance of overweight.

Study
The researchers measured the BMI, waist circumference and cortisol concentration in the hair of 2,527 people over 50. They analysed 2-cm lengths of head hair. Because the hair on our heads grows 1 centimetre per month, these measurements provided a picture of the cortisol concentration in the bodies of the participants over the previous two months.

Results
There was more cortisol in the hair of the participants who were a couple of kilograms [Overweight] too heavy than in the hair of the participants who were a healthy weight [Normal-weight]. And they found even more cortisol in the participants who were dangerously overweight – those who had a BMI of over 30 [Obese].

The researchers observed a similar relationship between cortisol and waist circumference. The men had higher cortisol levels in their hair when their waist measurement was 102 cm or more. The women had more cortisol in their hair when their waist measurement was 88 cm or more.

The relationships between cortisol, overweight and a thick waist were statistically significant.

Mechanism
"Chronic stress - and thus chronically elevated levels of cortisol - may promote obesity through effects on fat accumulation," the Brits wrote. "The effects of cortisol are mediated via glucocorticoid receptors, which have a particularly high density in visceral adipose tissue."

"In the presence of insulin, cortisol promotes triglyceride accumulation and retention in visceral fat depots which results in increased abdominal fat. [Hum Reprod. 1997 Oct;12 Suppl 1:21-5.] Indeed, animal studies have shown that chronic exposure to physical and psychological stressors increases deposition of visceral fat. [Am J Primatol. 2009 Sep;71(9):742-51.] [Physiol Behav. 1992 Sep;52(3):583-90.]"

"In addition to influencing fat deposition, cortisol is associated with alterations in the quantity and type of foods consumed. Laboratory studies in humans have shown increased ad libitum caloric intake in response to glucocorticoid infusion and artificially induced stress. [Am J Physiol. 1996 Aug;271(2 Pt 1):E317-25.] [Psychoneuroendocrinology. 2001 Jan;26(1):37-49.]"

"In addition to absolute changes in energy intake, functional MRI studies have indicated that the sensitivity of central food reward circuits is lower during times of stress, which may increase cravings for 'comfort foods'. [Int J Obes (Lond). 2010 Jan;34(1):172-81.] Under stress, there is a shift in preference toward more palatable, energy-dense foods irrespective of whether total energy intake increases. [Physiol Behav. 2006 Apr 15;87(4):789-93.] [Psychosom Med. 2000 Nov-Dec;62(6):853-65.]"

Conclusion
"These results provide consistent evidence that long-term exposure to elevated levels of cortisol over several months is associated with higher levels of adiposity," the researchers concluded.

"Hair cortisol offers a suitable and easily obtainable measure for assessing chronically elevated cortisol concentrations in obesity research and may therefore aid in further advancing understanding in this area."

"While cross-sectional studies have provided a good starting point from which to explore the role of hypothalamic-pituitary-adrenal axis dysregulation and chronic cortisol exposure in the development of obesity, longitudinal research is needed in order to clarify the direction of associations."

Source:
Obesity (Silver Spring). 2017 Mar;25(3):539-44.

More:
People with low cortisol levels have younger looking face for longer 21.12.2016
Relaxation exercise halves cortisol level 08.07.2009
Stress course lowers athletes' cortisol level 13.06.2009

Archives:
Blocking Cortisol

Pomegranate reduces cortisol by a third Pomegranate reduces the amount of the stress hormone cortisol in the body. This increases insulin sensitivity and, as a result, blood pressure decreases.	One capsule of fish oil daily lowers cortisol levels The participants in tis study were alcohol addicts who were doing a detox, but the cortisol lowering effect of fish oil is no different in healthy people.	Green tea inhibits cortisol synthesis Green tea is a cortisol inhibitor, and it may well be a very effective one.