Beat the December Slump: Light Exposure + Vitamin D
(H2L Studio Blog | December 2025)
Shorter days. Darker mornings. Cloudier everything.
If you’ve felt more tired, unmotivated, or “meh” lately — you’re not imagining it.
When sunlight goes down, so do our:
- Mood
- Energy
- Metabolism
- Immune function
- Sleep quality
That’s because light is one of the strongest signals to your brain that says:
“Wake up, feel good, let’s move.”
And in the winter… that signal gets really quiet.
But you don’t have to let your energy crash with the season. Here’s how to fight back.
Morning Light = Better Mood + Better Sleep
Even 5–10 minutes outside (yes, even when it’s cloudy) triggers serotonin — the brain chemical that lifts mood, reduces anxiety, and later converts to melatonin to help you sleep deeper at night.
The earlier you get light, the better your body clock runs.
Morning Light Ritual
- Step outside within 30–60 minutes of waking
- Look toward the daylight (not directly at the sun)
Your brain wakes up. Your metabolism wakes up. You wake up.
Why You Feel Sleepier in December
Less sunlight → higher melatonin during the day
More darkness → your brain thinks it’s bedtime all the time
So workouts feel harder, cravings increase, and motivation drops.
Solution? Give your body a stronger “daytime” signal:
- Open blinds the second you wake
- Keep living spaces bright during the day
- Schedule movement earlier when possible
Morning workouts = natural energy upgrade.
Vitamin D: The Winter Power Nutrient
Most people become deficient this time of year — and it impacts:
- Mood + depression risk
- Immune strength
- Bone health
- Hormones + metabolism
- Muscle function
Sunlight creates Vitamin D in your skin… but from Nov–March, sunlight isn’t strong enough to make much at all.
Foods that help:
- Salmon + fatty fish
- Egg yolks
- Mushrooms
Supplementation basics:
- Look for D3 (often paired with K2 is best for absorption)
- Typical range: 2,000–4,000 IU/day* (individual needs vary)
- Take it with a meal that has healthy fat
(*Always talk to your provider if you’re unsure what your level is.)
Light at the Right Time Improves Workouts
Training earlier in the day:
- Boosts focus + coordination
- Improves sleep quality later
- Supports metabolism and appetite regulation
When you move in the morning, you go into the day already winning.
Your December Energy Checklist
Try these daily:
✔ Step outside each morning
✔ Keep indoor lights bright until late afternoon
✔ Add Vitamin D-rich foods
✔ Take D3 (with K2 if recommended)
✔ Aim for an earlier workout 1–2x/week
Little shifts → major energy return.
Final Note
You deserve to feel awake, happy, and strong — even in the darkest month of the year.
Light is life. Movement is momentum.
Put them together, and December becomes a month you thrive through — not just survive.
Book a morning class at H2L this week — let’s bring your energy back into the light.