To understand the connection between food and cortisol, it’s helpful to first understand the hormone's basic function in the body.
Cortisol, also known as the "fight or flight" hormone, is a glucocorticoid hormone produced by the adrenal glands. Alongside its primary role as a response to anxiety or stress, the “stress” hormone is responsible for many important functions in the body, including maintaining blood glucose levels, regulating metabolism, and even controlling the immune system. It also plays a critical role in the balance between digestion and absorption of nutrients, and the conversion of food into energy.
Although the stress hormone often gets a bad rap, cortisol is critical for your body's ability to adapt to stress, and without it, you won’t be able to go on with your day-to-day life. However, chronically elevated cortisol levels can have negative effects on the body, including impacting the body's ability to produce certain hormones, resulting in impaired immune function, and even accelerating aging. That’s why it’s critical to keep stress levels in check.
In this edition, we're diving into the relationship between cortisol and food, and exploring 13 cortisol-lowering, nutrient-dense foods that can help us stay calm and healthy.
What is Cortisol and Why Should I Care?
Cortisol is a steroid hormone secreted by the adrenal glands in response to stress.
When we’re experiencing chronic stress, we often think of cortisol as the culprit that drives weight gain, but this hormone is essential for survival. Cortisol is involved in several biological processes, including responding to stress, regulating blood sugar levels, and managing immune system functioning. It is also produced in response to a wide range of physiological and psychological stimuli, including fear, pain, and lack of food.
Additionally, cortisol has many other roles in the body, such as increasing the availability of amino acids and glucose, and increasing the body's tolerance to pain. The physiology of stress and its relationship to disease is a complex subject, but cortisol plays a key role in the body's response to stress and its downstream effects on the body.
The effects of cortisol vary depending on the amount produced, the duration of its presence in the body, and the location of its actions.
What Are The Effects of Elevated Cortisol?
While low levels of cortisol are needed for proper immune and reproductive function, high levels of the stress hormone can be damaging to the body. Cortisol typically rises in the morning and then tapers off throughout the day.
However, many people are stuck in a pattern of chronically high cortisol levels. Chronically elevated levels of cortisol (e.g., in response to stress) are associated with a wide range of health consequences, including depression, insomnia, blood sugar imbalances, and elevated blood pressure. Elevated cortisol levels have also been linked to increased visceral fat, decreased bone density, and memory impairment.
What Foods Reduce Cortisol?
Salmon is a rich source of omega-3 fatty acids, which have been shown to reduce the body’s production of cortisol. Omega-3s are anti-inflammatory and help relax the muscles of the body, preventing the development of chronic conditions such as cardiovascular disease and high blood pressure. Eating a diet rich in foods like wild-caught salmon, or supplementing with products like fish oil, can help keep your cortisol in check. (Source)
One study found that eating one average-sized dark chocolate candy bar (1.4 ounces) each day for two weeks reduced levels of the stress hormone cortisol. It also reduced the “fight-or-flight” hormones known as catecholamines. Researchers hypothesize that chocolate’s stress-reducing properties are thanks to its flavonoids, which inhibit an enzyme involved in reducing cortisone to the active form cortisol. (Source, Source)
Turmeric is a potent anti-inflammatory and pain reliever that has been used for thousands of years in Ayurvedic medicine to treat inflammatory conditions ranging from arthritis to allergies. The active ingredient in turmeric, curcumin, is a phytochemical that modulates the expression of brain-derived neurotrophic factor, aka BDNF. The best way to consume turmeric is with piperine, the active compound in black pepper, as it makes the curcumin more bioavailable. (Source, Source)
Coconut oil is classified as a “functional food,” thanks to its anti-inflammatory, antimicrobial, and antidepressant effects. It’s rich in medium-chain fatty acids (MCFAs) which can quickly be converted into energy. As a result, coconut oil’s MCFAs have been shown to improve physical and mental performance, and reduce fatigue. In one study looking at the effects of the oil on exercise- and cold-induced stress, mice treated with virgin coconut oil showed increased levels of antioxidants in the brain, and lowered cortisol, triglyceride, and cholesterol levels. (Source)
Olive oil has numerous health benefits, thanks to its strong anti-inflammatory effects. Researchers believe that a phenolic compound found in olive oil called oleuropein may be responsible for reducing cortisol levels. (Source)
Bananas are a rich source of magnesium, which can help lower blood pressure, decrease cortisol, and improve sleep. They also contain tryptophan, which is a precursor to serotonin, a neurotransmitter that plays an important role in mood. A study of 20 cycling athletes showed eating bananas during a 75-km ride improved performance times by 5% and also recovery biomarkers, including cortisol levels. (Source)
One of the compounds found in mushrooms, called beta-glucans, can help lower cortisol levels. Beta-glucans are a type of fiber that can be found in many foods, including mushrooms, oatmeal, and barley. A study of 18 healthy men found that consuming a beta-glucan-rich mushroom supplement significantly lowered cortisol production, especially after exercising. (Source)
Ground flax seeds, also known as flax meal, are a good source of lignans, fiber, and alpha-linolenic acid (ALA), the plant-based omega-3 fatty acid. Flax seeds contain phytoestrogens, which can improve responses to stress (by lowering cortisol and blood pressure) and may offer protection against atherosclerosis (the narrowing of arteries). (Source)
Garlic is a natural antibiotic, antiviral, and antifungal agent. When garlic is chopped or crushed, it releases an amino acid compound called allicin, which has been shown to regulate blood pressure, lower cholesterol levels, and even improve muscle soreness. On the stress front, researchers have found that both raw and low temperature-aged garlic activated neuroprotective effects and significantly decreased the levels of stress-related hormones, including cortisol. (Source, Source, Source)
Asparagus is a rich source of glutathione, a powerful antioxidant that helps neutralize stress-causing free radicals and helps quell inflammation. Glutathione is used by the body to detoxify chemicals like heavy metals, pesticides, and solvents that are stored in fat cells. One study showed that asparagus extract appeared to exert “anti-stress” effects on cortisol levels and sleep quality. (Source)
This root has been used for centuries in traditional Eastern medicine for its anti-inflammatory, antioxidant, and immune-enhancing properties. More recently, researchers have explored the effects of ginger on cortisol levels and found that the root helps to modulate the stress response and reduce oxidative stress in animals. (Source, Source)
Onions are one of the most powerful foods for reducing cortisol levels and helping you to cope with stress. They contain sulfur compounds that have been shown to lower cortisol levels during stressful situations. In addition, onions contain flavonoids and quercetin, which are powerful antioxidants. In animal studies, onions have been shown to enhance stress tolerance and effectively fight off pathogens. (Source)
Green tea is one of the most powerful dietary supplements for lowering cortisol levels. The specific polyphenol in green tea, epigallocatechin gallate (EGCG), is a powerful anti-inflammatory that has been shown to calm the body and mind, and may help reduce the risk of inflammatory diseases. EGCG blocks the enzyme that converts the amino acid tyrosine into a hormone called norepinephrine, which is a stress- and anxiety-inducing hormone. Researchers found that EGCG inhibits the activity of an enzyme that converts from cortisone to cortisol. (Source, Source)
The bottom line on cortisol-reducing foods
Because many people are stuck in a pattern of chronically high cortisol levels and experience high cortisol related health consequences, consuming cortisol-reducing foods is a great way to manage a stressful lifestyle and reclaim your health. While implementing dietary changes are important to mitigate effects of high cortisol, it can sometimes feel overwhelming. Working with a WellTheory Nutritional Therapy Practitioner provides support, accountability, and guidance for individuals who want to use a lifestyle-first approach, through diet and supplementation, to manage their stress and autoimmune symptoms.