As we previously learned, cortisol is the main stress hormone involved in preparing the body to handle physical and mental stress. It affects every body system - metabolism, respiration, circulation, digestion, immunity, and more.
Can your diet influence cortisol levels, though? Notice what some scientific research has revealed:
The Journal of the International Society of Sports Nutrition set out to determine how fish oil supplements affected cortisol production in healthy adults. A daily 4 gram supply of fish oil lowered morning cortisol levels.
Another study found that fish oil supplementation prevented cortisol production caused my mental stress.
Omega 3 fatty acids can be found in salmon, sardines, mackerel and other oily cold-water fish.
One drink that has traditionally been associated with stress relief is tea. One study set out to investigate the effects of 6 weeks of regular black tea consumption on scientific measures of stress - including cortisol production.
After a 4 week wash-out phase with zero coffee, tea, and caffeinated beverages, 75 healthy men were given 6 weeks of treatment with black tea or placebo. After 6 weeks, all subjects were given two challenging behavioral tasks to complete. Then, different measures of stress were measured.
The group that drank black tea for 6 weeks showed lower blood levels of cortisol after the challenging task.
We are finding more and more compelling evidence for the link between brain function and gut bacteria. It appears that prebiotic consumption can influence how the brain processes information linked with anxiety and depression and can influence the stress response.
The strong neurological effects prebiotics can have are clearly seen in rat studies. However, a recent study set out to find how two prebiotics can influence cotisol secretion in humans.
Two prebiotics - fructooligosaccharides (FOS) or Bimuno®-galactooligosaccharides, (B-GOS) - or a placebo were given to 45 healthy individuals every day for 3 weeks.
After 3 weeks of regular prebiotic consumption, all individuals had to complete a computerized activity.
There was a lowered stress response in those who consistently took B-GOS.
You can find a high amount of prebiotics in foods such as garlic, leeks, onion, asparagus, Jerusalem artichokes, and chicory. Other foods with prebiotics include bananas, sweet potatoes, yams, savoy cabbage, barley, rye, dandelion greens, beetroot, fennel bulb, green peas, snow peas, sweet corn and whole wheat.
Yep, the humble H2O. Were you expecting something more fancy? An interesting study found that periods of dehydration were associated with greater concentrations of cortisol.
BANANAS & PEARS
While this exercise study focused on bananas and pears, it is more than likely any fruits can apply. When compared with just water, exercise perfomance improved and, yet, cortisol production was lower.
A study published in the Journal of the American College of Cardiology found that flavonoid-rich (an antioxidant) dark chocolate intake buffered the stress response in humans at the level of the adrenal gland.
Study subjects were given either a flavonoid-rich 72% dark chocolate or a placebo chocolate made with flavonoid-free white chocolate that was dyed, flavor-matched, and aroma-matched to look, smell, and taste like dark chocolate. Two hours after ingestion, subjects were given a three part stress test that included a mock job interview and an arithmetic task to complete in front of an audience.
The study's dark chocolate group did not have high cortisol production, compared with the placebo group, after the stress test.
Do you see a pattern?
While most of these foods may have but a modest effect on cortisol production, they can help decrease the impact of stress in your life. They are all anti-inflammatory, nutrient-dense, or beneficial for overall health.
Inflammation encourages extra cortisol production. Maintain an anti-inflammatory diet to control cortisol. That is the key - a nutrient-dense diet with high quality protein, plenty of fresh produce, whole instead of refined grains, and quality, unprocessed fats.
An anti-inflammatory diet is more than just consuming anti-inflammatory foods. It requires minimizing inflammatory foods or habits - foods or meals with a high-glycemic load, caffeine, excess alcohol, trans fats, a low-fiber diet, a low intake of antioxidants, a sedentary lifestyle, and being overweight.
Not only will these help keep cortisol production under control to the extent possible, but they help keep blood sugar under control when eaten in proper proportion to each other.
If you have sensitivities to specific foods, try to limit or avoid them to prevent additional cortisol from possibly being produced.
Finally, don't underestimate the importance of getting adequate restful sleep.
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