How not to get sick this winter

Remember your mom yelling at you to wear a jacket so you don't "catch a chill and get sick"?

Turns out, she wasn’t exactly correct (although her heart was in the right place!).

The cold truth about winter illness

Cold air itself doesn't make you sick. Viruses make you sick. But your mom's intuition wasn't totally wrong – there's a reason we all get hammered with colds and flu between November and March.

Here's what's actually happening:

Viruses love winter. Cold, dry air is basically a viral playground. Influenza and other respiratory viruses survive longer and transmit more efficiently in cool, dry conditions, which is exactly what we create when we crank up the heat indoors. The virus particles linger in the air, waiting for their next host.

We become indoor sardines. Winter = more time inside, closer together, breathing the same recycled air. Add in holiday gatherings and kids packed into classrooms, and you've got a perfect transmission network for every pathogen making the rounds.

Your immune system takes a hit. Your immune system changes seasonally. Some immune responses are less robust in colder months, and your mucosal barriers (your body's first line of defense) don't work as well.

But, one of the biggest culprits? Vitamin D.

The vitamin D winter slump

When sunlight hits your skin, your body makes vitamin D3. Less sun = less vitamin D. And vitamin D isn't just about bones; it's also a critical immune regulator.

Studies show that maintaining serum vitamin D levels above 38 ng/mL is associated with a two-fold reduction in acute viral respiratory infections. Military recruits with adequate vitamin D had significantly fewer upper respiratory infections during winter training.

Vitamin D helps your immune cells produce antimicrobial peptides (natural germ-fighters), regulates inflammation, and supports both your innate and adaptive immune responses. When your vitamin D tanks in winter, so does your ability to fight off infections.

What you can do about it

Your mom's jacket won't save you, but these things will.

Get morning sunlight. Even 10-15 minutes of morning sun exposure helps regulate your circadian rhythm, which directly impacts immune function. Bonus: it also supports melatonin production later in the day, which affects immune response, too.

Supplement with vitamin D3. Most people need 2000-5000 IU daily in winter months to maintain optimal levels (that's why your HOP Box includes 2500 IU). If you're really committed, get your levels tested and aim for 40-80 ng/mL.

Add a humidifier. Dry indoor air helps viruses survive and irritates your respiratory tract. Keeping humidity between 40-60% makes it harder for viruses to hang around and easier for your mucous membranes to do their job.

Prioritize sleep. Your immune system does critical maintenance work while you sleep. Skimp on sleep and you're basically leaving the door open for every bug that comes knocking.

Keep moving. Even micro-movements throughout the day support immune function and help regulate the inflammatory response that can make you feel terrible when you do get sick.

Space out when you can. Yes, we know – winter gatherings are part of the joy. Just maybe don't share drinks, wash your hands, and give the person coughing in the corner a wide berth.

The bottom line

Yes, wear the jacket. But also: take your HOP Box, get outside in the morning, and maybe invest in that humidifier.

Your immune system will thank you.