Chapter 4 - 80% Of Your Body Composition Is Determined By How You Eat Flashcards
Chronically excessive insulin production interferes with the optimal function of what hormones?
- Appetite hormones
- Sleep hormones
- Thyroid hormones
- Sex hormones
- Stress hormones
Glucagon
- The counter regulatory hormone to insulin
- Responsible for mobilizing stored fuel into the bloodstream for use as energy
- Secreted by the pancreas (as is insulin)
Glucagon response to macros
Carb ingestion = suppression of glucagon + increase in insulin
Protein ingestion = slight increase in both insulin and glucagon
Fat ingestion = no effect on insulin or glucagon
Leptin
Produced by fat tissue
A key hormone for regulating:
- appetite
- satiety
- fat metabolism
- reproductive functions
Influences:
- production and distribution of sex hormones (primary role = priming the body for reproductive success: stimulating appetite and/or fat storage as needed to ensure the body has enough energy on board…
Involved in processes that regulate:
- bone density
- onset of puberty
- immune function
Low Leptin
Interferes with menstruation and fertility
Other signs include:
- Hunger
- Depession
- Low energy
Chronically High Leptin & Inflammation of the Hypothalamus
Can lead to Leptin resistance (receptors unable to read leptin’s signals)
- Results in a vicious cycle of overeating and excessive fat storage
Leptin Sensitivity can be improved by:
- Moderating carbohydrate intake
- Avoiding pro-inflammatory foods
- Getting good sleep
- Limiting fructose intake
- Lowering blood triglycerides (if they are chronically high)
- Avoiding prolonged caloric deficit — if they have been following a very low carb diet for a long period of time, then they may want to experiment with carb cycling to stimulate leptin synthesis
Ghrelin
“Hunger hormone”
- Secreted by the stomach pre-prandially (before eating)
- Main function = keep us from starving by stimulating appetite and increasing reward value of food, and priming the body to utilize the incoming energy
Stimulates growth hormone
Activates areas of the brain involved with learning and memory
CCK (Cholecystokinin)
Peptide hormone
- Produced in the small intestines
- Stimulates secretion of digestive enzymes (from the pancreas) and bile (from the gallbladder) into the intestines to facilitate the digestion of protein and fat, respectively.
- Regulates rate of protein and fat digestion —> slows down intestinal contractions, which slows rate down digestion so that the small intestine can effectively digest proteins and fats from a meal.
— This helps promote satiety…
Cortisol
Belongs to the glucocorticoid family
Produced by the adrenals in response to signals sent from the Hypothalamus via the pituitary glands
Levels usually peak in early morning, influenced by sunlight in the human circadian rhythm
Levels usually diminish in the evening, allowing the sleep-inducing hormone melatonin to rise into prominence in the bloodstream
Healthy Levels of Cortisol
Support the regulation of:
- Energy levels
- Metabolic function
Mobilizes:
- Fatty acids, glucose, and amino acids for use as energy
A critical component to fight-or-flight response is cortisol triggering the conversion of amino acids (ingested or stored) into glucose for quick energy via gluconeogenesis
It is a catalyst for peak performance by increasing:
- Alertness
- Heart rate
- Blood pressure
- Fuel mobilization
Chronic/Excessive Production of Cortisol
- Suppresses immune function
- Has a catabolic effect on lean tissue
- Accelerates the storage of fat (particularly in the abdomen —> where cortisol receptors that promote fat storage are more concentrated)
Chronically high levels are believed to:
- increase appetite, particularly for sugar, by influencing levels of appetite hormones such as leptin, corticotrophin releasing hormone (CRH) and neuropeptide Y (NPY)
Can result in:
- High blood pressure, due to sugar cravings and gluconeogenesis, a state of hyperglycemia (high blood sugar)
Three-fold Stress Response
- Stimulus
— Or stressor, from the environment - Perception
— of the stimulus (example: seasoned vs. novice speaker response) - Response
— on a biochemical level
“It follows that you have a choice in how you perceive stimulus, which will then directly impact your physiological response to this stress…”
“… When a person is able to reframe his or her perception of an environmental stimulus, they gain some control over the involuntary chemical/hormonal elements of the stress response…”
General Adaptation Syndrome
Three-phase process of the stress response (Hans Seyle)
- Alarm
— occurs when stress hormones flood the bloodstream (fight-or-flight response) - Resistance
— immediate & extreme elements of the fight-or-flight response subside, but stress hormones still circulate in the bloodstream at an elevated level, affording heightened cognitive and physical performance
— a person can remain in this phase for days & weeks - Exhaustion
— when the resistance phase continues for too long, the body’s stress coping mechanisms are exhausted:
- elevated cortisol drops
- immune function becomes vulnerable to infection
- brain performance declines
- physical fatigue is prolonged…
Testosterone
Primary male sex hormone
Presides over:
- Muscle growth and recovery
Promotes:
- Physical strength
- Body & facial hair
- Sex drive
- Competitive drive
Women estrogen to testosterone ratio = 2:1
A gradual decline in testosterone is believed to be a major marker of aging for both sexes
Increase in Abdominal Fat in Males Associated with
Declining Testosterone/
Elevated Cortisol
High-insulin-producing, fat-storage-promoting diet creates a negative feedback loop:
- Abundant abdominal fat produce more estrogen than is optimal for men
- Luteinizing hormone (LH), released from the pituitary gland to regulate testosterone production, is disturbed by excess estrogen
— In females, this can throw off normal ovulation cycles
— In men, the interference with LH signaling can cause the testes to produce less testosterone
To improve sex hormone balance:
- First, improve sleep habits
— during sleep, testosterone & growth hormone production are elevated - Conduct brief, intense exercise sessions, which promote a genetically optimal acute elevation of adaptive hormones into the bloodstream
- Moderate carbohydrate intake and insulin production
— to improve insulin sensitivity and normal delivery of testosterone and human growth hormone to target hormones - Maintain optimal Vit-D levels
— primarily through sun exposure; - Eating ample levels of saturated fat, monosaturated fat, and cholesterol
- Avoiding sugary foods that cause glucose spikes and insulin responses
- Obtain adequate zinc from dietary sources, such as shellfish
*Break the cycle of carb dependency, chronic cardio, inadequate sleep, excessive life stress —> can optimize testosterone levels in both males and females…
*In rare cases, low carb/insulin can reduce testosterone levels… this person could experiment with increased carb intake to improve performance without sacrificing health benefits of a diet that optimizes insulin production
