Cortisol: How The Stress Hormone Is Impacting Your Health And Body Composition

Cortisol is a hormone that is produced by the adrenal gland in response to stress. It is known as the "stress hormone" because it is released in response to physical or emotional stress. It plays a critical positive role in regulating various normal physiological processes such as blood sugar, blood pressure, and immune function. A normal cortisol spike is also why our body wakes up in the morning, for example.

Though there is no need to fear cortisol, chronic stress *can* lead to excessively high cortisol levels, which can have negative effects on the body, including weight gain, increased blood pressure, decreased immune function, muscle loss, and increased risk of chronic diseases.

How The Food We Eat Impacts Cortisol

Some of the food we eat can impact cortisol levels in several ways. Studies have shown that the following dietary factors can affect cortisol levels:

1. Caffeine

   Caffeine is a stimulant that can increase cortisol levels. A study conducted on 16 healthy adults found that consuming caffeine resulted in a significant increase in cortisol levels. While moderate amounts of caffeine are generally safe for most people, excessive consumption can lead to high cortisol levels and other health problems. It is important to nuance that caffeine is often consumed in conjunction with exercise (ex. pre-workout supplements) or mental stress (ex. exam season for students, or to get an energy kick during a stressful day at work). The interactions of caffeine and stress on cortisol secretion have not been explored adequately in women.

2. Alcohol

   Alcohol consumption can also increase cortisol levels. A study conducted on 17 healthy men found that consuming alcohol resulted in a significant increase in cortisol levels. It is important to consume alcohol in moderation and to be mindful of how it affects your body.

3. Healthy fats

   Consuming healthy fats, such as those found in nuts, seeds, avocados, and fatty fish, can help lower cortisol levels. One study found that a diet high in monounsaturated fatty acids resulted in a significant decrease in cortisol levels compared to a diet high in saturated fatty acids. This is partly because healthy fats help stabilize blood sugar levels, which in turn helps regulate cortisol levels.

How Cortisol Impacts Body Composition

Chronically elevated cortisol can impact body composition in several ways. Studies have shown that the following effects can occur:

1. Weight gain in the abdomen

   High cortisol levels can lead to weight gain, particularly in the abdominal area. This is because cortisol can increase appetite and promote the storage of fat in the abdominal area. A study conducted on 47 women found that those with high cortisol levels had higher levels of abdominal fat.

2. Muscle loss

   High cortisol levels can also lead to muscle loss, particularly in the legs and arms. This is because cortisol can break down muscle tissue to release amino acids, which can then be used to produce glucose (aka your body’s favourite energy source).

3. Bone loss

   High cortisol levels can also lead to bone loss, particularly in postmenopausal women. This is because cortisol can interfere with the production of new bone tissue. A study conducted on 61 postmenopausal women found that those with high cortisol levels had lower bone mineral density.

How to Reduce High Cortisol Levels with Lifestyle Habits

Fortunately, there are several lifestyle habits that can help reduce high cortisol levels. Based on current scientific studies, here are a few examples:

1. Exercise

   Though exercise also increases cortisol levels short term, regular exercise can help reduce cortisol levels in the long term. It is important to remember that cortisol has many positive impacts on the body, and is necessary to induce post-exercise adaptations (such as muscle gain, for example). Exercise releases endorphins, which are natural mood boosters, and can help reduce stress and anxiety. A study conducted on 60 healthy young adults found that participating in regular aerobic exercise resulted in a significant decrease in cortisol levels.

2. Mindfulness practices

   Mindfulness practices, such as meditation and deep breathing exercises, can help reduce cortisol levels. A study conducted on 57 adults found that participating in a mindfulness-based stress reduction program resulted in a significant decrease in cortisol levels. Another study by Brand et al. (2012) found that mindfulness practice can impact cortisol levels. The study explored the impact of long- and short-term meditation experiences on hypothalamus-pituitary-adrenocortical system activity (HPA SA) and sleep. The study found that long-term meditators had lower cortisol levels than short-term meditators and non-meditators. The study also found that long-term meditators had better sleep quality than short-term meditators and non-meditators.

3. Sleep

   Getting enough quality sleep is essential for regulating cortisol levels. Sleep deprivation can increase cortisol levels and disrupt the body's natural circadian rhythm. A study conducted on 17 healthy men found that sleep deprivation resulted in a significant increase in cortisol levels. It’s ideal to aim for anywhere between 7-9 hours of sleep per night on average for most adults (some might need more, but it’s a good place to start).

4. Healthy diet

   Consuming a healthy diet can also help reduce cortisol levels. Eating a diet rich in fruits, vegetables, lean protein, and healthy fats can help stabilize blood sugar levels and reduce inflammation, which can in turn help regulate cortisol levels. A study conducted on 30 healthy adults found that consuming a diet high in fruits and vegetables significantly decreased cortisol levels. A Mediterranean-style diet can be interesting to look into if this is something that interests you.

To sum up…

Cortisol plays a critical and positive role in regulating various physiological processes in the body, but chronic stress can lead to high cortisol levels, which can have negative effects on body composition and overall health. By making lifestyle changes such as regular exercise, mindfulness practices, getting enough quality sleep, and consuming a healthy diet, individuals can help reduce high cortisol levels and promote overall well-being.

To help put some of these lifestyle changes in place, you might benefit from consulting with a professional, such as a psychologist or Registered Dietitian.

Hope this helped!

Maria Tanielian
Registered Dietitian/Nutritionniste
ODNQ # 7223, CDBC # 2815, SDA # 949

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References:

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