Immune System
Your body's defense force. The immune system protects against pathogens, clears damaged cells, and maintains tissue integrity. It's a complex network of cells, organs, and signaling molecules. Balance is key—too weak or too strong causes problems.
Two Arms of Immunity
Innate Immunity
First line defense. Born with it. Fast but non-specific. Physical barriers, NK cells, macrophages, neutrophils.
Adaptive Immunity
Learned response. Specific targeting. Memory cells. T cells and B cells. Takes days but precise.
Key Immune Cells
T Cells
Coordinate immune response. Helper T cells, cytotoxic T cells, regulatory T cells. Made in thymus.
B Cells
Make antibodies. Memory for future infections. Plasma cells produce immunoglobulins.
Natural Killer Cells
Kill infected and cancer cells. Part of innate immunity. First responders.
Macrophages
Engulf pathogens. Present antigens. Clean up debris. Tissue-resident.
Neutrophils
First to infection site. Short-lived. Major component of pus. Fast responders.
Dendritic Cells
Antigen presenters. Bridge innate and adaptive. Activate T cells.
Key Nutrients for Immunity
Vitamin D
Master immune regulator. Activates T cells. Reduces autoimmunity. Most are deficient.
Zinc
Essential for immune cells. Shortens cold duration. Thymus function. Don't overdose.
Vitamin C
Supports white blood cells. Antioxidant. Concentrated in immune cells. High doses when sick.
Vitamin A
Mucosal immunity. First line barriers. T cell function. Don't overdo.
Selenium
Antioxidant enzymes. Viral defense. T cell function. Brazil nuts.
Glutathione
Master antioxidant. Immune cell function. NAC to support. Crucial for immunity.
Gut-Immune Connection
GALT
Gut-associated lymphoid tissue. 70% of immune cells here. Largest immune organ.
Microbiome
Trains immune system. Produces immune-supporting metabolites. Diversity matters.
Leaky Gut
When barrier fails. Immune activation. Systemic inflammation. Autoimmunity link.
Probiotics
Support immune balance. Strain-specific effects. Reduce infections.
Fiber/Prebiotics
Feed beneficial bacteria. Produce short-chain fatty acids. Immune regulation.
Secretory IgA
First line mucosal defense. Made in gut. Binds pathogens.
Lifestyle Factors
Sleep
Critical for immunity. Cytokine production. Repair happens during sleep. 7-9 hours.
Stress Management
Chronic stress suppresses immunity. Cortisol effects. Meditation, nature, connection.
Exercise
Moderate exercise boosts immunity. Too much can suppress. Balance is key.
Sunlight
Vitamin D production. Beyond just D—direct immune effects. Regular exposure.
Avoid Sugar
Sugar suppresses immune function. For hours after consumption. Limit processed foods.
Social Connection
Loneliness impairs immunity. Positive relationships boost it. Community matters.