Ray Peat on adrenaline

November 29, 2025

Adrenal response to inflammation and stress hormones

"When the body detects inflammation or other stress (possibly by perceiving changes in blood sugar, lactic acid, or carbon dioxide – or all of them together), its adrenal glands will release anti-stress hormones, including adrenaline and cortisol (provided these glands are not exhausted or undersupplied). Both adrenaline and cortisol can raise blood sugar levels to meet the increased demand."

Nutrition for Women

Blood sugar as an integrating factor for stress

"Based on my own experience, I tend to believe that blood sugar is an important integrating factor and that the body can probably perceive small or rapid fluctuations that would be very difficult to detect using standard laboratory methods. For example, it is known that men, in particular, release adrenaline under the stress of having blood drawn, which tends to increase blood sugar levels."

Nutrition for Women

Metabolic effects of caffeine and adrenaline on sugar and fat utilization

"Since both caffeine and adrenaline increase the metabolic rate, fat is presumably burned more quickly. Adrenaline is known to raise blood sugar, apparently by inhibiting the use of glucose and increasing the use of fat. Coffee normally raises blood sugar due to its adrenaline-like effect."

Nutrition for Women

Effects of coffee and adrenaline on glycogen depletion during fasting

"During fasting, coffee and/or adrenaline can accelerate the depletion of glycogen reserves and thus cause hypoglycemia to occur more quickly."

Nutrition for Women

The influence of vitamin C on tyrosine metabolism and adrenaline levels in tissue

"Tyrosine metabolism, which is involved in brain function, is sensitive to vitamin C. Furthermore, vitamin C maintains adrenaline levels in tissues – possibly by inhibiting its oxidation – and adrenaline is necessary for chalones to perform their function, namely to inhibit cell division."

Nutrition for Women

Salty snacks and improved sleep quality

"Salty snacks are particularly helpful in making it easier to fall asleep, presumably by stabilizing blood sugar and lowering adrenaline. Ice cream, which combines sugar, calcium and some fat that delays sugar absorption, is often effective in improving sleep quality."

– March 2018 – Ray Peat's Newsletter

The effects of hypothyroidism on skin and adrenaline production

“Many people with hypothyroidism compensate for this by producing high levels of adrenaline (sometimes up to 40 times higher than normal), which causes the skin to remain cool, especially on the hands, feet, and nose. The high adrenaline is a consequence of low blood sugar, so consuming carbohydrates, such as a glass of orange juice, can sometimes temporarily lower the heart rate.”

– Generative energy: Restoring the wholeness of life

The role of adrenaline in depression, stress and inflammation

"Elevated adrenaline – similar to elevated cortisol levels – is a characteristic of depression, stress, and inflammation; through the mobilization of fats, it can become part of a vicious cycle in which free fatty acids cause insulin resistance and thereby activate stress responses."

– February 2001

The unique receptor behavior and tissue interaction of estrogen

"The effect of estrogen on many tissues increases the tissue's ability to bind estrogen; estrogen thus stimulates the formation of its own receptors – in a self-stimulating and simultaneously self-destabilizing process. This differs from the behavior of other receptors, such as the adrenaline receptor, which is inactivated by increased adrenaline exposure. This unusual interaction between tissue and hormone warrants careful investigation."

– March 2000

Hypothyroidism and excessive activity of the adrenergic nervous system

"In hypothyroidism, the adrenergic nervous system tends to be overactive, and adrenaline production remains at a high level even when there is no external reason for it, because adrenaline is needed to maintain sufficient blood sugar levels and enough energy in the inefficient metabolic state of hypothyroidism."

– January 2000 – Ray Peat's Newsletter

The role of estrogen in the mobilization of free fatty acids and edema

"Adrenaline mobilizes free fatty acids from tissues, including fat and muscle tissue. Estrogen itself leads to increased free fatty acids. If the free fatty acids are unsaturated, they cause edema by making the blood vessels more permeable."

– January 2000 – Ray Peat's Newsletter

The role of the thyroid gland in sleep and energy production

"Since I had become a deep sleeper as soon as I started taking thyroid, and had seen that thyroid alone could cure most people's insomnia (sometimes, as one doctor described his experience, even better than morphine), I began to understand that the adrenaline that was disrupting sleep was an indication of faulty energy production, and that the things that restored sleep—for example, thyroid, salt, sugar, protein, and progesterone—acted directly on the cells' energy production."

– January 2000 – Ray Peat's Newsletter

Effects of salt and thyroid gland on blood pressure and sleep

"Since elevated adrenaline tends to raise blood pressure, I started explaining the effects of salt and the thyroid to friends over 80. They found that they slept better, had more regular heartbeats, and didn't get swollen feet when they consumed a normal amount of salt. Their blood pressure didn't rise as a result."

– January 2000 – Ray Peat's Newsletter

Eating salty foods before bed can improve sleep.

"I have recommended salty foods before bed to promote sleep because of sodium's known anti-adrenaline effect. There is some complicated thinking about its effect on adrenaline, just as there are explanations for its thermogenic effect, but the simple fact that sodium is needed for glucose uptake may explain its ability to lower adrenaline (since adrenaline rises when glucose is needed) and increase heat production."

1998 – Ray Peat's Newsletter – Issue 4

The importance of thyroid hormones for sustained brain energy

"Thyroid hormones are crucial for providing the brain with a consistently high energy level. When these hormones are lacking, our nerves require stimulants to function normally, and our body typically produces large amounts of adrenaline to keep us going. The result is that we are simultaneously tired and tense."

April 1994 - Ray Peat's Newsletter

The influence of carbohydrates and salt on brain energy and relaxation

"The brain is like a muscle and needs to replenish its energy in order to relax. Many people have noticed that they feel tired after consuming a lot of carbohydrates and/or salt. Both salt and carbohydrates tend to lower adrenaline levels, and carbohydrates can also increase the activity of thyroid hormones while restoring tissue energy."

April 1994 - Ray Peat's Newsletter

Effects of stress on glucose and fat utilization

"If tissues are not adequately supplied with oxygen, glucose is rapidly depleted. During prolonged stress, the liver's gluconeogenic response to glucocorticoids, as well as its ability to produce and store glycogen, is reduced. Because glucose is less available, adrenaline levels in the blood rise, and fat is mobilized from stores as an alternative energy source. Free fatty acids, especially unsaturated fats, are toxic to the mitochondrial respiratory system because they block both oxygen utilization and energy production. The increased use of fats instead of glucose leads to an increase in lipid peroxidation."