Sometimes you're really stressed out....I know.
And sadly (as you may have thought) this can get in the way of your fat loss goals by slowing down your metabolism.
And now you're intrigued - just how much does it slow down my metabolism by?
Let's go and investigate.
Stress and Fat Loss
In this study (1), the researchers gave 58 women in total meals with the macronutrient ratio of:
+ 36 grams protein
+ 60 grams fat
+ 59 grams of carbohydrates
The women had an average age of 53, and after the meal their energy expenditure and blood was examined.
Over half of the women were breast cancer survivors; they were expected to be under more stress than other women. A questionnaire was given to them to see see to what extent this was true.
Stress And Metabolism
So what did they find?
Their calorie expenditure was high upon finishing the meal, but as the hours went on it decreased.
And as might have been expected - the reduction of energy expenditure was quicker in the women who said they'd been plagued with stress from the day earlier - this included any arguments in the home or workplace or something more serious.
Check out the graphs below to see how the "0 stressors" scored higher on both the calories burnt after the meal and fat oxidation observations.
And now fat oxidation:
It's obvious that the stress didn't help them.
The authors paint a bleak picture - "this study provides novel evidence of metabolic pathways through which prior day stressors and past depression facilitate weight gain over time."
So how much of a big deal is this over a year? Let's hear from them again:
"Greater numbers of prior day stressors were associated with decreased postmeal energy expenditure. The cumulative difference between one recent stressor and no stressors over 6 hours translates into 435 kJ, averaged across meal type and group and all controlling variables. This difference would add up to almost 11 pounds [5 kg] across a year."
Stress is a very real issue for a lot of people, particularly those in this study.
Cortisol and Weight Gain - Is it Making You Fat?
Now the stress hormone cortisol can wreak havoc on your waistline (2), however it's a very misunderstood hormone. First of all, it's HOW MUCH that's being secreted that's a problem.
Like everything else in the fitness industry, hormones and certain foods are always painted as either "BAD" or GOOD" with no inbetween, without any effort to decipher what they really are!
Cortisol is not the boogie man people make it out to be - it's released during food intake, exercising, awakening, and too during psychosocial stressors (3-6).
Now yes, "Cortisol directly effects fat storage and weight gain in stressed individuals" (2), but remember the normal amount secreted during daily life (seperate to severe stress) is not as bad as some people may tell you.
For instance as I mentioned above, fasting increases cortisol, as does eating, so if you went on a low calorie diet to avoid it - well that would also increase cortisol too (7).
What I'm getting at is - don't live your life by trying to AVOID cortisol totally, and assume it's the boogie man - it's not. You also can't run away from it.
If you have a lot of stress in your life - whilst exercise increases cortisol - in can also be used to control it; exercise has been shown to cause an overall "reduction in circulating cortisol levels" (8).
Practical Application - Fighting Cortisol and Stress Induced Weight Gain
So deal with stress with some exercise, and do whatever activities in your life help "de-stress" you.
These may be vastly different for a lot of people...
But whatever you do - don't live your life trying to run away from cortisol secretion, as it's not as terrible as some may suggest!
"Stay Fit, Stay Flexed!"
References
(1) Kiecolt-Glaser JK, Habash DL, Fagundes CP, Andridge R, Peng J, Malarkey WB, Belury MA. Daily stressors, past depression, and metabolic responses to high-fat meals: a novel path to obesity. Biol Psychiatry. 2015 Apr 1;77(7):653-60. doi: 10.1016/j.biopsych.2014.05.018. Epub 2014 Jul 14.
(2) Maglione-Garves CA, Kravitz L, Ph.D, Schneider, S Ph.D. Cortisol Connection: Tips on Managing Stress and Weight. ACSM'S Health & FItness Journal: September/October 2005 - Volume 9 - Issue 5 - pp 20-23.
(3) Ely, D.L. Organization of cardiovascular and neurohumoral responses to stress: implications for health and disease. Annals of the New York Academy of Sciences (Reprinted from Stress) 771:594-608, 1995.
(4) McEwen, B.S. The brain as a target of endocrine hormones. In Neuroendocrinology. Krieger and Hughs, Eds.: 33-42. Sinauer Association, Inc., Massachusetts, 1980.
(5) Vicennati, V., L. Ceroni, L. Gagliardi, et al. Response of the hypothalamic- pituitary-adrenocortical axis to high-protein/fat and high carbohydrate meals in women with different obesity phenotypes. The Journal of Clinical Endocrinology and Metabolism 87(8) 3984-3988, 2002.
(6) Wallerius, S., R. Rosmond, T. Ljung, et al. Rise in morning saliva cortisol is associated with abdominal obesity in men: a preliminary report. Journal of Endocrinology Investigation 26: 616-619, 2003.
(7) Tomiyama et al. Low calorie dieting increases cortisol. Psychosom Med. 2010 May;72(4):357-64. doi: 10.1097/PSY.0b013e3181d9523c. Epub 2010 Apr 5.
(8) Hill et al. Exercise and circulating cortisol levels: the intensity threshold effect. J Endocrinol Invest. 2008 Jul;31(7):587-91.
Author
Dayne Hudson