Why Vitamin D Deficiency is 70% Higher in February.

G'day Legend,

Emailing you from Austin. I stayed a few extra days after the marathon to take advantage of the sun, because right now towards the back end of February, vitamin D is at its lowest point of the year. A 2023 study of 7.9 million people found vitamin D deficiency is 70% more prevalent in late winter than summer and February is the peak of it. We're missing out on essential micronutrients that impact your energy, testosterone, and recovery. Here's what to do about it.

In this week’s newsletter (4 min read):
⚡ What Vitamin D Actually Does
💊 Why Taking a Pill Won't Fix It
🐟 The Foods That Close the Winter Gap

If you’ve got a mate struggling with winter blues, send them THIS link — it might turn things around until the sun comes back out.

What Vitamin D Actually Does

Vitamin D is a fat-soluble vitamin that acts more like a hormone than a regular vitamin. Think of it like a performance coordinator on your sports team.

It powers your mitochondria, the energy generators inside your cells, helping you actually produce energy from food. It also supports testosterone production, which influences muscle repair, strength, drive, and recovery. Think of testosterone as your strength and conditioning coaches. Vitamin D keeps that system fully staffed.

When you don't get enough, it's like training with dim stadium lights and an understaffed coaching crew. You still put in the work, but you feel flatter, recover slower, get sick more often, and notice a dip in motivation. Not just "winter blues." Your performance system is missing a key player.

Why Taking a Pill Won't Fix It

This one I love explaining because I never like pills (ask Milena).

The problem is that vitamin D doesn't work alone. Three things need to line up for it to actually do its job:

1. Fat for absorption Vitamin D is fat-soluble, so taking a dry tablet with black coffee on an empty stomach means you're barely absorbing it. It's like signing a great athlete and never putting them on the field. Take it in liquid form suspended in oil, with your fattiest meal of the day.

2. The right dosage The standard 600–800 IU recommendation prevents severe deficiency, not optimal performance. Most adults in northern latitudes through winter need 1,000–4,000 IU daily to hit the 40–60 ng/mL sweet spot. The only real way to dial in the right number is blood work.

3. The right teammates

• Vitamin K2 directs calcium into bones and teeth where you actually want it. Without it, you're recruiting more players onto the team but giving nobody a position to play. The very best sources are grass-fed animal products like Force of Nature.

• Magnesium converts vitamin D into its active form. Without it, vitamin D can't fully activate. It's like having a star athlete on the roster who never makes it to game day.

Taking a standalone vitamin D pill without fat, K2, and magnesium is like building a team around one star player and expecting championships. Which is why for the past 5 years I've taken Vitamin D3 + K2 from AG1 through winter. Sign up for AG1 and I'll throw in a full year of D3 + K2 for free HERE.

The Foods That Close the Winter Gap

No food truly replaces summer sun. In peak conditions your body produces thousands of IUs just from being outside. But in winter when UVB drops off completely, the right foods meaningfully close the gap.

Fatty fish are your heavy hitters. Wild salmon delivers 800–1,000 IU per 3.5oz. Mackerel and sardines are strong starters, and canned sardines are the best value draft pick in the game. Get them in 3–4x per week and the omega-3s cover recovery and inflammation too.

Eggs are your reliable starter. Pasture-raised yolks contain 3–6x more vitamin D than conventional. Two to three daily with healthy fat and you're absorbing well.

UV-exposed mushrooms are your utility player and the only meaningful plant-based source. A 3oz serving gives you 400 IU or more. Look for "UV-exposed" on the label.

Great teams build depth. So even with these on rotation, I still use D3 + K2 through winter. Grab the free AG1 deal HERE.

Quick Protocol

• Fatty fish 3–4x per week

• 2–3 pasture-raised eggs daily

• UV mushrooms 2–3x per week

• D3 + K2 supplement with your fattiest meal

February is the low point — everything you do right now compounds into how you feel come spring, so eat the salmon, get your D3 + K2 sorted, and keep showing up without coasting through on empty.

Giveaway Winner🎁 

Drumroll please!! The winner of the Force of Nature regenerative meats box is Angelina Howe! Congratulations Legend, and thanks to all who entered! We have new rewards monthly, so lots of opportunities for

This Week's Recipe: One Tray Salmon Fettuccine

This is an epic meal to that that vitamin D and omega-3s. Get the full recipe HERE.

Quick Notes

🏃 Congrats to everyone who ran Austin this weekend. Blown away by how many of you are cooking from this newsletter!

🎥 Just locked in an incredible YouTube guest. No fear whatsoever. You're going to love them.

🏋️ Locked in for Houston Hyrox. Who's coming?

#EatGoodFeelGood

— DC