The Thyroid

Facts

• Ancestral origin developed as animals left sea• Active starting from fetal age “week 4”• Secreting at fetal age “week 18”• Responsible for packaging iodide and

transporting it into the cell• Also houses parafollicular cells (calcitonin)• Shields the parathyroid gland (parathormone)

Post thyroidectomy testing:

Salmon Calcitonin

pathology

• Hypothyroidism –underactive

• Hyperthyroidism-overactive

• Subclinical Hypothyroidism-underactive

Hypo

• Age• Infections (viral)• Surgical• Auto “digestion” (auto immunity s/e)• Radiation (2011 Tohuko Earthquake/Tsunami)• Cancer • Drugs (lithium)

Hypo symptoms

• Fatigue/weakness• Weight gain• Depression• Low voice• Constipation • Poor memory• Intolerance to cold• Brittle nails, dry skin, coarse/thin hair• Irregular mense (>5-7 d)

Long term Hypo

• Intellectual disability/social out casting• Psychological labeling• Myxedema coma• Heart failure +/-

hyper

• Autoimmune (early phase)• Pregnancy• Foods• Infection/inflammation• Iatrogenic

Hyper symptoms

• Nervousness/anxiety• Weight loss• Insomnia• Irregular heart beat• Diarrhea • Hyperhydrosis, rash, thin falling hair

Long term Hyper

• Heart enlargement• Myxedema (thick skin shins/feet)• Graves ophthalmopathy • Psychological labeling

“Subclinical” Hypo

• “Wastebasket Dx”• Blood tests normal• All the symptoms of Hypo• Some studies show females > 60 = 20%

Long term Subclinical Hypo

• Social withdrawal• Psychological labeling• Withdrawal from western medicine (+)• Small % go onto Hypo

Imbalances in a nutshell

• T4 (thyroxine) • T3 (triiodothyronin)• TSH (thyroid stimulating hormone)

T4

• The cool molecule created by land animals to carry iodide throughout the blood and deliver to the cell-most attached to TBG

• Most thyroxine is bound (but free is included in the total)

• Free is “active” can be calculated (FreeThyroxineIndex)

• Free T4 (0.9-1.8ng/dL)

T3

• Less in amount but also attached to TBG• Seems to have greater effect on the way the

body utilizes energy• Better to get free T3 (240-450pg/dL)

Exogenous hormone• Levothyroxine sodium (levothyroid, levoxyl, synthroid)• Dessicated thyroid (armour/nature thyroid)• Armour=corn fed/Nature=grass fed)• Compounded Armour• Liothyroinine sodium (cytomel)• Liotrix (thyrolar)• Compounded Liotrix

• The New England Journal of Medicine 1999;340:424-429, 469-470

TSH

• Hormone secreted by the pituitary gland• Increase means brain thinks thyroid slow• Decrease means brain thinks thyroid fast

• Supersensitive TSH (1-1.5mIU/L)• THR (thyroid releasing hormone for pituitary loop function)

Thyroid antibodies

• Thyroid peroxidase antibody• Antithyroglobulin antibodies

• Problem: what is causing the antibodies to attack?

• Further investigation (Naturopathy)

Goitrogens

• Cabbage• Brussel sprouts• Broccholi• Califlower• kale

Iodine

• Supplanted by the government in salt, and in some countries flour and cooking oil

• Potassium iodide created after dash diet • Lack of can cause goiter or low production

thyroid• Poor nutrition bringing back low iodine • Chlorine, florine, bromine compete