Cortisol Issues

Increasing fat intake in your diet really is a hot topic lately with so much new information coming out debunking some of the myths that we previously believed to be fact. I personally believe that we could all benefit from eating a little bit more of it and reducing the carb intake to a certain extent, or timing our carbs a bit better, which I have written about previously.

Now after last weeks post on the high fat ketogenic diet, there was a question from Taz who asked about the effect of high fat diets on cortisol levels and in turn the effect this has on hormones, especially in women. I answered this question under the blog briefly, but the more I thought about it, the more I realized that I should do a full post on this as I’m sure there are many others out there in a similar situation.

The question was – “I have been gradually shifting away from carbs to a higher fat diet, but had been advised recently that a high fat diet in women can affect hormone levels. Particularly where cortisol levels are already too high. Thoughts?”

Before we answer the question with a long winded response, let’s take a look at the body’s stress hormone, cortisol. We produce cortisol as a response to any stress in the body, whether it be physical or emotional. Running definitely fits into the physical side of things (personally I think it has a positive effect on the mental side of stress…) as it is actually a rather large stress on us as the body needs to repair the muscles that have been damaged during the session. The cortisol is produced, does it’s job, then the body gets rid of it as it’s no longer required.

If everything worked that well, all would be good. The problem is, in today’s society, we get up in the morning and stress our body with a run, have a quick bite to eat, get cleaned up and out the door for work, where we can almost be assured of a full day’s stress. We come home at night, still full of stress, get a poor nights sleep, only to get up the next day to repeat the whole process. In times like this, our body is in so much stress, it starts to forget to switch off the stress response, so our cortisol levels remain elevated, almost permanently.

The effects of this can be quite dramatic, with reduced thyroid function, blood sugar issues, poor sleep, decrease in muscle mass, decreased healing of wounds, high blood pressure, poor immune system and hormonal issues in women (leading to infertility in extreme cases).

So the question is, what can we do about it? I’m definitely not going to tell you to stop exercising as I would hate to have to do this myself and really don’t think it is the right answer. But we do need to look at ways of reducing the stress on the body. First, when I talk about high fat diets, I also talk about lowering the carbohydrate intake. But this has to be taken into context. Not eating enough carbs to recover after a training session can definitely increase cortisol levels.

As athletes, we do need carbs and a bit more than the average person for obvious reasons. I just like to time them around training to get the best effect from them. The high carb foods I eat, such as bananas and sprouted grain breads are all eaten as recovery foods within 30 minutes of exercise along with some protein. Ensuring correct carb intake after exercise can definitely reduce the stress on the body, in turn reducing your cortisol levels.

Reducing the amount of stress through the rest of the day can be done by taking a relaxing walk for lunch, breathing deeply and not hunching over the computer, meditating, sleeping an appropriate amount of hours (8-9 for athletes per night) or even looking at some herbal remedies like ashwagandha, an Indian herb that reportedly has a positive effect on chronically high cortisol levels.

As far as high fat diets go, there is some evidence to show that they can raise cortisol levels. In relation to a ketogenic diet, this is generally a temporary thing as your body adapts to the new way of eating (generally 2 weeks). But once you are fully ketogenic, the levels should come back to normal. But if you are just increasing the amount of fat you eat to a more moderate level than the full ketogenic method, you really don’t need a huge amount of it. It doesn’t need to be any more than 25-30 of your whole caloric intake.

If all else fails, just treat yourself to a holiday on a tropical Island for a week. It’s almost impossible to stress in that situation. Unless the airlines lose your baggage!

Run Well

Chris O’Driscoll

Leave A Reply (2 comments so far)


  1. Taz
    3 years ago

    Great answer, & has assured me I’m on the right path. Thanks for taking the time to delve into it further Chris


  2. Chris
    3 years ago

    No problems Taz, glad to be of service.
    Chris.

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