9a. Stress Flashcards
What is stress?
Non-specific response of the body to any disturbance or demand
When can stress become harmful to the body?
Extreme
Chronic
Causes of stress
Poor nutrition - processed diets, high alcohol intake
Personal - financial, family, work
Poor body functions - injury, illness
Environmental - radiation, pesticides, industrial/household chemicals
What are the three stages of stress (Hans Selye)?
Alarm phase
Resistance phase
Exhaustion phase
What happens during the alarm phase of stress?
Fight or flight
Hypothalamus triggers SNS
SNS triggers adrenals to release adrenaline and noradrenaline
Anterior pituitary releases ACTH which triggers adrenals to release cortisol
What is the role of cortisol in the alarm phase?
Provides additional glucose
Increases pain threshold
Inhibits immune responses
What happens during the resistance phase of stress?
Alarm phase abates
Individual returns to a state of equilibrium
What is the exhaustion phase of stress?
Happens when stress is prolonged and individual doesn’t return to resistance phase
What happens to cortisol levels during the exhaustion phase?
Decrease
What does repeated surges of cortisol lead to?
Cortisol dysfunction
What can cortisol dysfunction lead to?
Inflammation
Pain
Depression
GI issues
Increased risk of CV disease/cancer
What happens during cortisol dysfunction?
Prolonged/excessive cortisol secretion leads to desensitisation of glucocorticoid receptors to cortisol
This leads to cortisol resistance
How does cortisol resistance affect corticotrophin releasing hormone (CRH)?
Negative feedback
Because of CR, cortisol isn’t working so CRH keeps pumping out messages to release more cortisol
How does the continued release of CRH affect other hormones?
Increases mast cell activation
Release of noradrenaline (pro-inflammatory)
Upregulates glutamate in amygdala to promote a fear-based response to stress
How does cortisol go from being anti-inflammatory to pro-inflammatory?
High surges of cortisol increase its affinity to bind to mineralocorticoid receptors
Makes cortisol pro-inflammatory
Examples of conditions where stress-induced inflammation is implicated
CVD
Fibromyalgia
CFS
RA
IBD
What are the negative physiological effects of inflammation?
Causes oxidative stress
Free radical damage
Cellular death
Ageing
Systemic tissue damage
What are the physiological effects of prolonged cortisol secretion?
Increased risk of T2D and IR
Weight gain with central adiposity
Suppresses reproductive function
Impaired immune function
Suppressed thyroid function
Suppressed GI function
Downregulates the endocannabinoid (eCB) system
How does prolonged cortisol secretion increase the risk or IR and T2D?
Increases gluconeogenesis
Decreases glycogen synthesis
Leads to hyperglycaemia
Inhibits beta cell insulin secretion
Impairs insulin-mediated glucose uptake
How does prolonged cortisol secretion lead to weight gain with central adiposity?
Stimulates appetite and intake of highly palatable foods
Causes accumulation of fat in visceral fat cells
IR and hyperglycaemia sends hunger signals to brain leading to overeating
How does prolonged cortisol secretion suppress reproductive function?
CRH suppresses secretion of GnRH
This disrupts release of FSH and LH, oestrogen, progesterone, testosterone
How does prolonged cortisol secretion impair immune function?
Increases infection susceptibility
Decreases T-cell proliferation
Downregulates T-helper cell receptors
Inhibits neutrophil, macrophage and NK cell activity
How does prolonged cortisol secretion suppress thyroid function?
Inhibits enzyme that converts T4 to T3
Shunts T4 to inactive rT3
How does prolonged cortisol secretion suppress GI function?
Alters gut motility (impairing digestion and elimination)
Increased visceral perception (perception of pain/discomfort)
Downregulates HCl
Increased intestinal permeability
Dysbiosis
GORD, IBD, IBS, SIBO
What is the endocannabinoid system?
Helps us to manage pain, inflammation, hunger, metabolism
Which conditions is the downregulation of the eCB system linked to?
Depression
Fibromyalgia
Migraine
IBS
Examples of conditions linked to chronic stress
Anorexia nervosa
Asthma
Cancer
CVD
CFS
Recurrent infections
T2D
IBS
Ulcers
Headaches
Hypertension
PMS
Thyroid disorders
How does persistent stress initially affect the HPA axis?
Hyperactivation of the HPAA
Examples of conditions associated with hyperactivation of the HPAA?
Depression
Anxiety
Metabolic syndrome
How does ongoing persistent stress affect the HPAA?
Hypoactivation of the HPAA
Examples of conditions associated with hypoactivation of the HPAA
Fatigue
Pain
CFS
Fibromyalgia
Arthritis
Along with cortisol, adrenaline and noradrenaline, which other hormone is secreted by the adrenal glands in response to stress?
DHEA
What is the role of DHEA in stress?
Protects against negative consequences of stress
Protects against effect of high cortisol in brain
Reduces anxiety/depression
What does ongoing stress with prolonged DHEA and cortisol release lead to?
Adrenal exhaustion
Signs/symptoms of adrenal exhaustion
Fatigue
Continued need for sleep
Inability to cope with stress
Recurrent infections
Low libido
Sweet cravings
Sensitivity to cold/heat
Poor digestion
What does raised cortisol and normal DHEA mean on a test?
Normal, short-term stress
What does raised cortisol and raised DHEA mean on a test?
Chronic stress
What does raised cortisol and low DHEA mean on a test?
First sign of adrenal fatigue
What does low cortisol and low DHEA mean on a test?
Adrenal exhaustion
Natural approach to stress
Anti-inflammatory diet - fresh fruit/veg
Stabilise blood glucose - whole grains, legumes, nuts, seeds, fish, eggs, brown rice, quinoa, oats
Tryptophan rich foods (brown rice, quinoa, oats, eggs, bananas) for serotonin/melatonin production
Glutamine rich foods (cabbage juice, bone broth, turkey, asparagus) for intestinal permeability
Increase potassium rich foods (depleted in stress)
Microbiome support - pre/probiotics
Avoid refined carbs, alcohol, caffeine
Abdominal breathing prior to meals
Bitter foods 15 mins before meals
Mindful eating
O3 - to support eCB system
Cold water exposure - hot/cold therapy
Why is vit C important in supporting stress?
Antioxidants to mop up stress-created free radicals
Adrenal support
Reduce stress-induced cortisol release
Enhance immune function
Why is B5 important in supporting stress?
Precursor to acetyl-CoA (steroid hormone synthesis)
Increases production of glucocorticoids
Reduces secretion of cortisol in times of stress
Dosage for B5 in times of stress
100-300mg/day
Why is B6 important in supporting stress?
Modulates GABA and serotonin (neurotransmitters that regulate pain perception, anxiety, depression)
Downregulates activity of glucocorticoid receptors, reducing the physical impact of corticosteroid release
Dosage for B6 in times of stress
50-100mg/day
Why is a high dose B complex important in supporting stress
Formation of Acetyl-CoA (key for ATP production)
Maintain nervous system health
Neurotransmitter synthesis
Improve mood
Why is vit E important in times of stress?
AO
Protects adrenal cortex from free radicals
Supports immunity
Dosage for vit E in times of stress
400-800iu/day
Why is Mg important in times of stress?
Downregulates HPA activity by reducing cortisol and ACTH
Co-factor for GABA synthesis
Co-factor in serotonin-melatonin pathway
Why is L-theanine important in times of stress?
Increases serotonin, dopamine, GABA levels
Aids relaxation
Why can reishi mushrooms support stress?
Adaptogen
Sedative action
Assists immune system in times of stress
(increases NK cells, lymphocytes, macrophages)
Examples of herbs for stress
Chamomile
Passionflower
Lavender
Lemon balm
Ashwagandha
Siberian ginseng
Examples of lifestyle strategies for stress
Exercise
Acupuncture
Massage
Reflexology
Optimise sleep hygiene
Go for walk in daylight
