What Actually Keeps You Healthy This Holiday Season
And why it costs less—and works better—than immune gummies
There is a lot of bad bugs out there
The influenza this year is nasty, COVID is coming, and you are not wnting to be sick for the holidays.
This time of year, the message is everywhere: take more zinc, more vitamin C, more immune gummies. The implication is that if you just buy the right product, you’ll avoid getting sick.
That’s not how the immune system works.
The truth is far less profitable—but far more reliable. The things that most strongly protect you from influenza, COVID, and other respiratory infections cost little or nothing, and they work better than anything you’ll find on a supplement shelf.
Here’s what the science actually supports.
First: your immune system doesn’t need a “boost”
The immune system is not something you turn up like a volume knob.
If it’s over activated, people don’t get healthier—they get inflammation, autoimmune disease, and worse outcomes during infections. What we want isn’t more immune activity. We want immune balance: the ability to respond when needed and shut down when the job is done.
That’s why the supplement promises fail under scrutiny. Vitamin C doesn’t prevent colds. Zinc may shorten symptoms slightly. Gummies don’t train immune cells to behave better. I buy gummies at the movie as candy - and suspect any gummy as just being that, and as helpful as you think candy might be.
Balance does.
Sleep: the most powerful immune tool you already have
Sleep is not passive rest—it’s active immune regulation.
When you sleep well:
Immune cells coordinate more effectively
Antibody production improves
Inflammatory signals quiet down
Hormones that support immune balance rise
Large genetic and population studies now show that chronic poor sleep increases the risk of respiratory infections, including influenza and COVID, and increases the risk of hospitalization when people get sick.
Sleep deprivation weakens both:
Innate immunity (your first line of defense)
Adaptive immunity (long-term protection and vaccine response)
If you want one intervention that delivers more immune benefit than any supplement, it’s consistent, good-quality sleep.
Movement: do it regularly, not heroically
Regular movement is one of the most reliable ways to support immune health.
Moderate physical activity:
Lowers chronic inflammation
Improves immune surveillance
Reduces stress hormones
Improves metabolic health
During the pandemic, people who went from sedentary to moderately active just a few days a week had better outcomes when they got sick.
More is not always better. Prolonged, intense exercise without recovery can temporarily suppress immunity. The immune system responds best to daily, moderate movement—walking, light resistance training, moving after meals.
No special gear is required.
Food: where immune balance is built
About 70% of your immune system is connected to your gut.
That’s where immune cells learn what’s dangerous, what’s harmless, and when to calm down. That education depends heavily on what you eat.
Dietary patterns linked to better immune outcomes consistently include:
Fruits and vegetables
Adequate fiber
Fish and healthy fats
Minimal ultra-processed foods
Micronutrients matter, but they work as part of a system—not as isolated fixes. Vitamin D, zinc, and vitamin C can play supporting roles, but they don’t replace food patterns.
Your immune system responds to real food, not marketing claims.
Stress: real, measurable, and often ignored
Chronic stress weakens immune function.
Persistently elevated stress hormones:
Reduce immune cell responsiveness
Impair antibody production
Increase baseline inflammation
Decrease vaccine effectiveness
The holidays amplify stress for many people—less sleep, more obligations, more pressure.
Managing stress isn’t indulgent. It’s preventive medicine.
Even small steps help:
Protecting sleep
Daily walks
Saying no when needed
Lowering unrealistic expectations
Your body keeps the score.
What wearables confirm (but don’t fix)
Data from wearables like Whoop and Withings show the same patterns across millions of users:
Poor sleep → higher resting heart rate, lower recovery
Alcohol → fragmented sleep and delayed physiologic rebound
Chronic stress → slower recovery metrics
Consistent habits → better resilience
Alcohol is one of the clearest examples. Even one or two drinks reliably disrupt sleep and recovery—exactly what immune studies have shown for decades.
Here’s the key point:
You don’t need a device to act on this. OK, I wear Withings - and like them, because their watch looks awesome, and I am a data nerd.
Wearables didn’t discover new biology. They simply made visible what we already knew. The solution isn’t better tech—it’s better habits.
The bottom line
As many people want to sell you more zinc, more gummies, and more “immune support,” the truth is simpler:
What works best:
Sleep
Daily movement
Real food
Stress management
Vaccination when appropriate
What costs less:
All of the above
What works better:
All of the above
Boring works.
Boring works reliably.
A final thank-you
To those who support this work as paid members—thank you. Your support allows me to keep this newsletter focused on evidence instead of hype.
And to everyone reading: I’m glad you’re here.
Staying healthy isn’t about buying more.
It’s about doing what works—consistently, and kindly.
Wishing you a calm, healthy holiday season.
Excellent read
Thanks for your science based Substack. Always happy to see it in my email feed. Wishing you happy holidays and a healthy new year.