Serotonin in Critical Illness: How Severe Disease Disrupts Mood Chemistry

How Does Critical Illness Affect Your Body’s Serotonin System?

Critical illness dramatically alters serotonin synthesis and function throughout the body, with blood serotonin levels potentially increasing 1000-fold during severe inflammation. This surge affects immune responses, blood clotting, cardiovascular function, and gut motility - making serotonin a key player in both the development of complications and the recovery process from serious illness.

Dr. Kumar’s Take

Understanding serotonin’s role in critical illness is crucial for intensive care medicine because it affects so many organ systems simultaneously. What’s particularly important is that critically ill patients often receive multiple medications that interact with serotonin pathways - opioids, antiemetics, and antidepressants - creating risk for dangerous serotonin syndrome. The key insight is that serotonin isn’t just about mood in the ICU; it’s about survival.

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The Biology of Loneliness: How Social Isolation Damages Your Body

How Does Loneliness Actually Change Your Body’s Biology?

Loneliness and social isolation trigger measurable changes in stress hormones, immune function, and inflammatory markers that accelerate aging and increase disease risk. Socially isolated individuals show elevated cortisol levels, increased inflammatory cytokines, weakened immune responses to vaccines, and altered gene expression patterns that promote inflammation while suppressing antiviral defenses - creating a biological environment that increases vulnerability to infections, cardiovascular disease, and premature death.

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How Vitamin C Levels Drop During the Common Cold—and What It Means for Recovery

Dr. Kumar’s Take:

This study from Scotland in the early 1970s shows just how fast vitamin C in our white blood cells can drop during a cold, falling to scurvy-like levels within a single day of symptoms! The researchers found that keeping vitamin C intake high, both before and during a cold, helps your immune cells recover their vitamin C stores much faster. If you want to bounce back from a cold as quickly as possible, a higher-dose vitamin C regimen could help your immune system do its job.

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