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The Vitamin Most U.S. Adults are Low in
LF Newsletter #126

Hey there - it’s Don.
Happy Friday!
Today we’ll be in the kitchen, looking at the top vitamin U.S. adults have lower than recommended levels in.
But speaking of the kitchen… there’s something else I’m cooking up… (classic dad joke transition)…
I’m putting together a private beta-group for something new I’m working on. This group will get early access.
More details will be coming out over the next several weeks and months.
Stay tuned.
Let’s jump in!
📋 What’s Inside
The vitamin most U.S. adults are low in
Dr. Andrew Huberman interviews Pavel Tsatsouline
Food sources for over 29 vitamins and minerals, top 100 best fresh meats from around the world, and more…
First time reading? Sign-up here.
💪 Deep Dive
The Vitamin Most U.S. Adults are Low in
Click here to read this on the Layman’s Fitness website
In December of 2015 my wife and I moved across the country from a college town in Texas to a town 40 minutes north of New York City.
It was an exciting time in life… newly married, new job, new location, etc…
But there was one change in particular that caught me flat footed.
The lack of sunshine.
New York City has just 5 hours of daily sunshine in January… and I bet you we had less than that during the winter we moved.
Most days I left for the office at 6:30am and left the office by 5p… so for the first time in my life there were days I didn’t see the sun.
All of a sudden I became a more melancholy, irritable, and moody.
This was my introduction to Vitamin D.
Most U.S. Adults Don’t Get Enough Vitamin D
Adults need at least 600 international units (IU) of Vitamin D every day.
For adults over 70 the recommendation is higher, at least 800 IU’s.
So how many U.S. adults get enough?
While the answer depends on the study you look at (and how it was run), here’s what a 2018 study published by Cambridge found:
28.9% of U.S. adults were vitamin D deficient (25-50 nmol/L)
41.4% of U.S. adults were vitamin D insufficient (50-75 nmol/L)
To quote their conclusion:
“… fewer than 30 % of US adults had sufficient vitamin D for optimal health outcomes”
These are staggering numbers.
P.S. Depending on the study you look at, you’ll find a range…
Some say ~60% are deficient & insufficient… some say 90%+ don’t get enough…
While the truth is probably somewhere in the middle… it’s undeniably far lower than recommended levels.
The Critical Supporting Role of Vitamin D
Vitamin D creation is remarkable… it’s one of those processes that happens without us having to consciously think about it.
Diving into this displays the brilliance of God.
Here’s what happens.
When UV light from the sun hits your skin, a reaction takes place that begins to create Vitamin D…. but it’s not quite ready to do it’s job yet.
So this Vitamin D compound is sent through your blood stream to the liver for the first conversion process.
Then this new compound is sent again through the blood stream to your kidneys for the second conversion process.
And then it’s sent to your small intestines to do one of it’s primary roles, which is helping the small intestines absorb calcium.
Calcium ensures bone strength and health, proper functioning of nervous tissue, muscle tissue, and much more.
For instance, if you have low Vitamin D and can’t absorb calcium from your food, your body starts pulling calcium from your bones… which leads to weaker and more porous bones.
Low levels of Vitamin D have also been linked to things like:
Bone softening
Mood changes
Seasonal affective disorder
Fatigue
Anxiety
Loss of appetite
Trouble sleeping
The body really is a system (1 Corinthians 12-14)… and each component, down to the tiniest vitamin, all have a pivotal role to play in this God designed, synergistic system.
How To Get Enough Vitamin D
So… how do we get enough Vitamin D?
There are two primary sources: sunlight and food.
Here’s a breakdown for both.
Vitamin D from sunlight
Here are the recommendations.
Daily sun exposure
10-15 minutes outside each day produces enough Vitamin D for most adults.
Optimal time is 10a-2p (when UV light is strongest), but other times work too
Expose face, arms, and hands
Get outside. Windows can block UV light
Works best in clear or partly cloudy weather. Overcast reduces UV exposure
30 minutes, 2-3x a week can also produce adequate amounts of Vitamin D
Total time depends on skin pigmentation
P.S. While sunscreen blocks UV light, not enough is typically used to block all Vitamin D production
Vitamin D from foods
Unlike other vitamins, not a lot of foods are high in Vitamin D.
Here are the some of the main ones.
Foods with High Vitamin D
Mackerel: 3oz = 600 - 1,000 IU
Wild-caught Salmon: 3oz = 570 - 1,000 IU
Trout: 3oz = 500-600 IU
Herring: 3oz = 400 - 600 IU
UV-exposed mushrooms: ½ cup = 450 - 1,000 IU
Sardines: 3oz = 300 IU
Tuna: 3oz = 230 IU
Eel: 3oz = 200 IU
Halibut: 3oz = 200 IU
Shrimp: 3oz = 50 IU
Beef liver: 3oz = 50 IU
Egg yolks: 1 egg yolk = 40 IU
Cheese (Swiss, Cheddar, Gouda): 1oz = 10-20 IU
P.S. There are other ways to get Vitamin D from consumption, like multi-vitamins, direct supplements, or fortified dairy products.
➡️ The Takeaway
Vitamin D plays a critical supporting role in calcium absorption, muscular, nervous, and mood regulation processes.
10-15 minutes of sun per day is enough to get what your body needs.
Some foods have Vitamin D, primarily fatty fish (salmons, mackerel, sardines, etc…)
God designed this incredible system to produce what we need on auto-pilot.
“I praise You, for I am fearfully and wonderfully made. Wonderful are Your works; my soul knows it very well”
To Him be the glory forever.
🔎 Finds
Here are some of my favorite finds/resources this week.
Top find
Dr. Andrew Huberman interviews Pavel Tsatsouline (more)
Pavel Tsatsouline’s research and content has totally changed how I thought about strength training.
And his work had a similar impact on Dr. Huberman, who interviews him on this podcast.
This is a loooooong one (~4 hours!), so here are some highlights:
- If you want to build strength, pick just a few exercises and focus on them (~7 minute mark)
- Once a week, jog a mile with a kettlebell weighing 30% of your bodyweight (~17 minute mark)
- Don’t seek the pump or burn, instead focus on anti-glycolytic training (2:11 mark)
- “Train to success, not to failure” (3:03 mark)
Other finds
Food sources for over 29 vitamins and minerals (more)
Science says this is the perfect way to boil an egg (more)
Back pain while sitting (more)
5-part checklist for breaking through a strength training plateau (more)
How to learn hanging leg raises (more)
Top 100 best fresh meats from around the world (more)
👍 Thanks for reading!
Here are some resources that can help your fitness:
The Home Gym Equipment List - 5 pieces of equipment I recommend (after having spent $1k+ on home gym equipment)
30 Day Weight Loss - Here’s a step-by-step guide on losing 5-10+ pounds in the next 30 days
KB Strength System - 1/1 coaching to give you everything needed to get strong and lose weight at home
I’ll see you next week.
Be strong,
Don
P.S. If you liked this dive into Vitamin D, let me know by hitting the polls below.
There are 20+ other critical vitamins and minerals that could be explored in future newsletters.
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