hormones, neurotransmitters, vitamins

Acetylcholine (ACh)

Enables muscle action, learning, memory; decreased in Alzheimer's

Dopamine

Pleasure, reward, motor control; low in Parkinson’s, high in schizophrenia

Serotonin

Mood, sleep, appetite; low levels linked to depression

Norepinephrine

Alertness, arousal, fight-or-flight; increased in anxiety

GABA (gamma-aminobutyric acid)

Main inhibitory neurotransmitter; low in seizures, anxiety

Glutamate

Main excitatory neurotransmitter; involved in learning and memory

Endorphins

Natural painkillers; released during exercise or stress

Epinephrine

Similar to norepinephrine; involved in fight-or-flight, increases heart rate

Histamine

Wakefulness, appetite, allergic response; involved in immune system

Vitamin A (Retinol)

Vision, immune function, skin health; deficiency causes night blindness

Vitamin B1 (Thiamine)

Nerve function, carbohydrate metabolism; deficiency causes beriberi

Vitamin B2 (Riboflavin)

Energy production, skin and eye health; deficiency causes cheilitis

Vitamin B3 (Niacin)

Metabolism, DNA repair; deficiency causes pellagra (3 Ds: dermatitis, diarrhea, dementia)

Vitamin B6 (Pyridoxine)

Amino acid metabolism, neurotransmitter synthesis; deficiency causes neuropathy

Vitamin B12 (Cobalamin)

DNA synthesis, red blood cell formation; deficiency causes megaloblastic anemia

Folate (Vitamin B9)

DNA synthesis, cell division; deficiency in pregnancy causes neural tube defects

Vitamin C (Ascorbic acid)

Collagen synthesis, antioxidant; deficiency causes scurvy

Vitamin D

Calcium absorption, bone health; deficiency causes rickets/osteomalacia

Vitamin E

Antioxidant, protects cell membranes; deficiency causes hemolytic anemia

Vitamin K

Blood clotting; deficiency causes bleeding

Insulin

Lowers blood glucose by promoting cellular uptake; secreted by pancreas

Glucagon

Raises blood glucose by promoting glycogen breakdown; secreted by pancreas

Thyroxine (T4)

Regulates metabolism; secreted by thyroid gland

Triiodothyronine (T3)

Active form of thyroid hormone; regulates metabolism

Cortisol

Stress hormone; increases glucose, suppresses immune system

Adrenaline (Epinephrine)

Fight-or-flight response; increases heart rate and energy

Aldosterone

Increases sodium and water reabsorption; regulates blood pressure

Antidiuretic hormone (ADH)

Promotes water reabsorption in kidneys; increases blood volume

Oxytocin

Labor contractions, milk ejection, bonding

Prolactin

Stimulates milk production after childbirth

Growth Hormone (GH)

Stimulates growth, cell reproduction; secreted by pituitary

Estrogen

Regulates female reproductive system and secondary sex characteristics

Progesterone

Maintains pregnancy, regulates menstrual cycle

Testosterone

Regulates male reproductive system and secondary sex characteristics

Parathyroid Hormone (PTH)

Increases blood calcium by stimulating bone resorption

Calcitonin

Lowers blood calcium by inhibiting bone breakdown

Melatonin

Regulates sleep-wake cycle; secreted by pineal gland