Most people who want to reduce stress are worried about cortisol. But remember, cortisol is essential to human life. By raising levels of blood glucose, cortisol provides the resources to combat stress from illness, trauma, fright, infection, and bleeding, among other things.
In general, cortisol deserves a high-five and a pat on the back, but it's a situational ally. There are times, as described above, when you want higher cortisol levels in your bloodstream, and there are times when you don't want a higher cortisol level. When it's allowed to run around all willy-nilly, cortisol can negatively affect growth hormone and testosterone output. It can also reduce muscle growth in general and increase abdominal fat, none of which are good if you're a lifter.
Luckily, there's an easy way to thwart high cortisol levels, and it involves something that's probably already in your supplement stash: fish oil.
In general, cortisol levels are highest in the morning and they generally taper off throughout the day. That's all good, provided the levels are within normal, healthy ranges.
However, cortisol spikes during and after a ball-busting workout. You'd prefer that it didn't happen because it can negatively affect muscle protein synthesis. And sometimes, cortisol levels, because of physical (overtraining) or mental stress, can remain perpetually elevated throughout the day and night. You definitely don't want that.
Sure, post-workout spikes of cortisol can be largely controlled by proper peri-workout nutrition, but sometimes, particularly during bouts of particularly heavy or intense training, your body needs some extra help. It turns out a modest amount of fish oil can be just the help you need in beating down cortisol, particularly if taken at bedtime.
A group of Italian researchers recruited 31 alcoholics to see if fish oil could lower cortisol levels. (When alcoholics stop drinking, their cortisol rises. The effect is temporary, but the cortisol is accompanied by feelings of stress and anxiety, which may in turn thwart their attempts to stop drinking.)
Ten were given placebo and 21 were given a 1,000 mg. capsule of fish oil containing a paltry 252 mg. of DHA and 60 mg. of EPA. The researchers monitored the subjects' saliva cortisol concentrations for 24-hour periods on the first and last days of the study. While the placebo capsules had zilch effect, the fish oil group had much lower cortisol levels in their saliva throughout the day. They also reported lower feelings of stress.
Granted, these effects were seen in alcoholics, but the cortisol-lowering effects of fish oil, as supported by other studies, is no different in non-alcoholics. Note, too, the amounts of omega-3 fatty acids (DHA and EPA) used in this particular study are much lower than those found in superior fish oils like Flameout®.
While the study didn't theorize as to the best time of day to take the fish oil, it seems logical that taking fish oil at dinner or even bedtime would be the best as it would reduce nighttime levels of cortisol and help you sleep.
This nighttime fish oil protocol would also help during times of overtraining as it would temper the highest-of-the-day morning cortisol spike so it doesn't hamper muscle protein synthesis or, worse yet, sacrifice muscle tissue to raise glucose levels.
Either take all your fish oil capsules at night, or take some of them during the day and take at least one at bedtime.
- Barbadoro P et al. Fish oil supplementation reduces cortisol basal levels and perceived stress: A randomized, placebo-controlled trial in abstinent alcoholics. Mol Nutr Food Res. 2013 Jun;57(6):1110-4. PubMed.