Stress is the organism's full response to a load that demands adaptation. Energy, structure, and orientation all move. Hans Selye described a nonspecific triad after many insults: enlarged adrenals, shrunken thymus and lymph tissue, gut damage. That is the classical general adaptation picture.

Walter Cannon described the same energy mobilization decades before Selye's triad. Strong emotion draws on a physical reserve.

That the major emotions have an energizing effect has been commonly recognized. Darwin testified to having heard, "as a proof of the exciting nature of anger, that a man when excessively jaded will sometimes invent imaginary offences and put himself into a passion, unconsciously for the sake of reinvigorating himself."

— Walter B. Cannon[1]

F. Z. Meerson and Anokhin give the working frame used here: stress hormones free material from idle tissue for the system under load; active tissue makes CO₂ that helps stabilize it.[2][3]

Energy is required to leave the defensive state. Low thyroid, high PUFA, gut endotoxin, or low glucose keep stress hormones high after the load is gone. See Mitochondria, Bioenergetics, Soviet medicine.

When diet keeps that reserve depleted instead of restoring it, low blood sugar and low thyroid function keep the same stress hormones elevated well past the load that triggered them, and the emotional energy Cannon described stops resolving. Anxiety and OCD cover that pattern in detail, including the blood sugar and meal-timing mechanisms specific to each.

PUFA and stress hormones

[edit]

Polyunsaturated fat stores feed a loop. Free PUFA stimulate ACTH, cortisol, adrenaline, glucagon, and prolactin. Those hormones free more fat. Without excess PUFA, the stress reaction is self-limiting.

When the diet has chronically contained more polyunsaturated fats than can be oxidized immediately or detoxified by the liver, the fat stores will contain a disproportionate amount of them... These PUFA stimulate the stress hormones, ACTH, cortisol, adrenaline, glucagon, and prolactin, which increase lipolysis, producing more fatty acids in a vicious circle. In the relative absence of PUFA, the stress reaction is self limiting.

— Ray Peat[4]

Saturated fatty acids terminate the stress reactions, polyunsaturated fatty acids amplify them.

— Ray Peat[5]

Calorie restriction raised cortisol and self-reported stress in dieters.[6] Intense exercise raises cortisol, prolactin, and estradiol acutely in athletes.[7] Aspirin blunts several exercise-related pituitary responses in a human RCT.[8]

See Free fatty acids, Randle cycle, Linoleic acid.

Gut and endotoxin

[edit]

The maladaptive sequence, starting from stress or hypothyroidism, would typically involve increased absorption of endotoxin, leading to interference with mitochondrial respiration, a shift to fat oxidation, inflammation, and the increase of a wide range of stress hormones.

— Ray Peat[9]

Chronic endotoxin load, hypothyroidism, and estrogen excess amplify stress hormone output. See Endotoxin, Tissue leakiness.

Inhibition and recovery

[edit]

Protective inhibition matters as much as excitation. GABA and glycine stabilize nerves and muscle. When that inhibition fails, cells become hypersensitive. That state shows up across heart disease, cancer, anxiety, allergies, epilepsy, nerve degeneration, and inflammatory shock. Excess dietary PUFA suppresses energy while intensifying excitatory signals from estrogen, cytokines, and serotonin.[10]

Meerson described a multi-level inhibitory anti-stress system. Nasonov's work showed that the right stimulation can raise resistance to later stress.[10] Overlap with functional systems: Soviet medicine, Pyotr Kuzmich Anokhin.

Stress networks raise PTH, serotonin, prolactin, and IL-6. That pulls calcium from bone toward soft-tissue deposit when unchecked. See Calcium, CO2.

Recovery supports: thyroid, progesterone, CO₂ retention, salt, glucose, lower PUFA, aspirin, niacinamide, gelatin/glycine, lower gut endotoxin. See Harm reduction.

[edit]

Caffeinated (but not decaffeinated) coffee attenuated chronic-unpredictable-stress mood and memory deficits in mice.[11]

Restraint stress lowered hippocampal ATP and produced lasting depressive behavior in mice; nicotinamide restored ATP and reversed the phenotype.[12]

Chronic stress hormones reactivated dormant disseminated tumor cells through neutrophil inflammatory signaling and oxidized-lipid release; beta-adrenergic blockade suppressed the path.[13]

After heart attack, survivors kept high basal cortisol and exaggerated catecholamine responses to mild noise.[14]

In type 2 diabetes, flattened daily cortisol variation associated with higher glucose.[15]

Maternal stress promoted preterm delivery through cortisol-driven FKBP51 inhibition of progesterone receptor activity in uterine decidua.[16]

Human prefrontal cortex mitochondrial complex I protein abundance tracks psychosocial load.[17]


Emotional suppression

[edit]

Suppressing emotion keeps the HPA axis and sympathetic nervous system activated longer than expressing it would. In a 12-year US cohort study, high suppressors had 35% higher all-cause mortality and 70% higher cancer mortality than low suppressors.[18] See Emotion.

[edit]

Adrenal fatigue is a popular label without a clear lab definition. Stress chemistry (cortisol, adrenaline) is real; the brand name is not a diagnosis. See Cortisol, Harm reduction.

Reproductive cost of sons

[edit]

Reproduction itself is a stress load, and sons cost mothers more of it than daughters. Male fetuses grow faster and weigh more at birth, and male offspring make greater lactational demands, so the "expensive son hypothesis" predicts a larger fitness cost to mothers from producing and rearing sons than daughters.[19] This dovetails with the broader finding that maternal condition and stress shift offspring sex ratio toward daughters: mothers under poor condition or environmental stress across many mammal species, including humans, tend to have relatively more female offspring, consistent with the Trivers-Willard prediction that resource-poor mothers do better investing in the lower-cost, lower-variance sex.[20]

See also

[edit]

References

[edit]
  1. ↑ Bodily Changes in Pain, Hunger, Fear and Rage, 1922
  2. ↑ Ray Peat, "Aging, estrogen, and progesterone," raypeat.com.
  3. ↑ Ray Peat, "Adaptive substance, creative regeneration," raypeat.com.
  4. ↑ Fats, functions and malfunctions., Ray Peat newsletter
  5. ↑ Fats, functions and malfunctions., Ray Peat newsletter
  6. ↑ Tomiyama AJ, et al. "Low calorie dieting increases cortisol," Psychosom Med. 2010. PMID 20368473.
  7. ↑ Gray AB et al., "Endocrine response to intense interval exercise," European journal of applied physiology and occupational physiology, 1993
  8. ↑ Di Luigi L et al., "Acetylsalicylic acid inhibits the pituitary response to exercise-related stress in humans," Medicine and science in sports and exercise, 2001
  9. ↑ Ray Peat, PhD on Endotoxin, Functional Performance Systems (compilation, not a primary source)
  10. ↑ 10.0 10.1 Ray Peat, "The GABA System, Defenses, and Tissue Renewal," Ray Peat Newsletter, 2008-05.
  11. ↑ Tomé AR, et al. "Regular intake of caffeinated but not decaffeinated coffee attenuates behavioral modifications in mice subject to chronic unpredictable stress," Neurobiol Stress. 2026. PMID 42495655.
  12. ↑ Wang Y, et al. "Nicotinamide and depressive-like behaviors," Behav Brain Res. 2021. PMID 33248165.
  13. ↑ Albrengues J, et al. "Stress hormones reawaken dormant cancer cells," Sci Transl Med. 2020.
  14. ↑ Mendelson GL, et al. "Hormonal status after myocardial infarction," J Clin Endocrinol Metab. 1974. PMID 4270621.
  15. ↑ Joseph JJ, et al. "Cortisol dysregulation and glycemia," Psychoneuroendocrinology. 2021.
  16. ↑ Guzeloglu-Kayisli O, et al. "FKBP51 and preterm birth," Proc Natl Acad Sci U S A. 2021.
  17. ↑ Trumpff C, et al. "Psychosocial experiences and brain mitochondrial biology," Proc Natl Acad Sci U S A. 2024. PMID 38889126.
  18. ↑ Chapman BP, et al. "Emotion suppression and mortality risk over a 12-year follow-up," J Psychosom Res. 2013;75(4):381-385. PMID 24119947.
  19. ↑ Invernizzi L, Lemaître JF, Douhard M. "The expensive son hypothesis," Journal of Animal Ecology. 2025;94(1):20-44. PMID 39473289.
  20. ↑ Navara KJ. "Programming of offspring sex ratios by maternal stress in humans: assessment of physiological mechanisms using a comparative approach," J Comp Physiol B. 2010;180(6):785-796. PMID 20544204.