Every now and again, cortisol is brought up as one of the greatest enemies of fat loss. The proposed ways to manage cortisol are numerous, including hormonal treatments and stress reduction, but nutritional alleviations seem to be the most popular.
One of the most recent examples of this is the idea that eating lower carbs (or no carbs) earlier in the day when cortisol is high can be a positive for body composition.
Carbs and Cortisol
Cortisol is a hormone that has the proclivity to store fat, and it tends to be slightly elevated in the morning hours. Thus, some have concluded that it is a good idea to stay away from carbs in the morning to prevent them from being converted into fat. There are two main problems with this reasoning:
1.) Daily fluctuations of hormones have not been shown to greatly impact neither fat loss nor fat gain, and likely hardly contribute at all.
2.) Consuming carbs actually blunts cortisol release.
So in reality, not only do natural daily variations in hormones not add up to a whole lot in terms of making you fatter or leaner, but the very same “bad” carbs that would turn to fat with cortisol present actually reduce the amount of cortisol in your blood when eaten.
So the take home message is:
If your Calories are in order (not too few, not too many) and you’re getting enough daily protein, carbs, and fats to meet your needs, there’s no real reason to worry too much about cortisol or about avoiding carbs in the morning.
Fat in Your Coffee
A closely related topic is the new trend of drinking coffee mixed with a fat source as a first meal – usually coconut oil, grass fed butter, or some combination of the two. One of the reasons this is advocated is the supposed beneficial effect of avoiding carbs when cortisol is elevated (which we debunked earlier). Now, there is some good to this meal idea; for instance, fat makes you really full for a long time and coffee has appetite-suppressant effects as well. On the downside, there are 4 distinct problems:
1.) Fat does not blunt cortisol nearly as much as carbs do, so now you still have high cortisol AND the fat supplied in the diet to add body fat. NOT a good combo!
2.) A lack of protein in a major meal of the day is a recipe to lose some muscle. Not much, but some. In order to stay healthy, shapely, strong, and lean, the best idea is to eat protein with every major meal. Skipping it at breakfast is not a good start.
3.) No carbs early in the morning can interfere with brain function, as carbs are a preferred food for the nervous system. If you have a job that requires lots of thought or physical activity (or both), some carbs in the AM might be a very good idea.
4.) Fat is REALLY Calorie dense, so consuming large amounts can be risky in elevating total daily Calories and thus risking fat gains.
On the whole, perhaps coffee with butter or oil isn’t the best idea as a breakfast. Removing some of the oil and adding in some lean protein and healthy carbs might make this breakfast a bit more nutritionally sound.