If you organized a vitamin popularity contest, commonly known nutrients like vitamin C would easily sweep the competition. But once you move beyond the initial letters in the alphabet (think: vitamin A, vitamin B, vitamin D3), you’ll discover there are other letter vitamins worth knowing.  
What Is Vitamin K?
When you see the term “vitamin K” it actually covers a family of compounds that include phylloquinone (vitamin K1) and a series of menaquinones (vitamin K2). According to the National Institutes of Health, vitamin K “functions as a coenzyme for vitamin K-dependent carboxylase, an enzyme required for the synthesis of proteins involved in hemostasis (blood clotting) and bone metabolism, and other diverse physiological functions.”

Here are some of the foods that contain the most amounts of vitamin K:

Collards
Turnip greens
Spinach
Kale
Carrot juice
Canned pumpkin
Okra
Pine nuts
Chicken
Top Other Letter Vitamin Brands
Looking for a new vitamin K supplement? How about phosphatidylserine? These wellness brands have what you need. 
Jarrow Formulas
Since 1977, Jarrow Formulas has been developing supplements that range from minerals and probiotics to vitamins and enzymes. No matter which product you choose, each supplement has been verified by the brand’s scientific panel, which closely monitors FTC and FDA regulations in the industry. 
Nordic Naturals
Nordic Naturals got its start with cod liver oil, which the Norwegian founder couldn’t find when he moved to California to attend graduate school). Each supplement goes through a rigorous testing process before hitting shelves, and the brand also gives back to global health organizations.  
Country Life
Founded in Long Island, New York in 1971, Country Life played a critical role in helping pass the 1994 Dietary Supplement Health and Education Act (DSHEA) and is known for becoming the first Certified Gluten-Free supplement brand in 2008.  
Best Letter Vitamin Supplements
From vitamin K to MK-7, here’s a look at some lesser-known vitamins. 
Jarrow Formulas PS 100- Phosphatidyl Serine
It’s a bit of a mouthful to pronounce, but phosphatidylserine (which you can shorten to PS) is a natural phospholipid found in cell membranes. This concentrated form is soy-free and made without non-GMOs. 
Nordic Naturals Vitamin D3 + K2
Gluten-free and Non-GMO Project Verified, Nordic Naturals offers the benefits of both D3 and K2 in one convenient gummy, which may help balance the levels of calcium and phosphorus in your blood. 
Tips for Choosing the Right Vitamins
Looking for the best vitamin supplements? Have a read through our guides to learn more about each nutrient you’re considering. 
Where to Find Vitamin A
One type of vitamin A (retinol) can only be found in animal sources (like dairy milk and butter). The other type (beta carotene) is plentiful in lots of different vegetables.  
How to Make DIY Vitamin C Gummies
Getting your kids to take their vitamins is easy when you offer a homemade gummy. A short list of ingredients (like grass-fed gelatin, raw honey, and vitamin C powder) makes easy work of this nutritious supplement.  
Vitamin D3 Benefits
If you aren’t getting enough daily sun exposure (news flash: many of us don’t), you may benefit from taking vitamin D3 supplements. Here’s our guide to “the sunshine vitamin.”

<p>If you organized a vitamin popularity contest, commonly known nutrients like vitamin C would easily sweep the competition. But once you move beyond the initial letters in the alphabet (think: vitamin A, vitamin B, vitamin D3), you’ll discover there are other letter vitamins worth knowing.</p>  
<h2>What Is Vitamin K?</h2>
<p>When you see the term “vitamin K” it actually covers a family of compounds that include phylloquinone (vitamin K1) and a series of menaquinones (vitamin K2). According to the <a href="https://ods.od.nih.gov/factsheets/vitaminK-HealthProfessional/"target="_blank">National Institutes of Health</a>, vitamin K “functions as a coenzyme for vitamin K-dependent carboxylase, an enzyme required for the synthesis of proteins involved in hemostasis (blood clotting) and bone metabolism, and other diverse physiological functions.”</p><br>

<p>Here are some of the foods that contain the most amounts of vitamin K:</p><br><ul>

<li>Collards</li>
<li>Turnip greens</li>
<li>Spinach</li>
<li>Kale</li>
<li>Carrot juice</li>
<li>Canned pumpkin</li>
<li>Okra</li>
<li>Pine nuts</li>
<li>Chicken</li></ul>
<h2>Top Other Letter Vitamin Brands</h2>
<p>Looking for a new vitamin K supplement? How about phosphatidylserine? These wellness brands have what you need.</p> 
<h3>Jarrow Formulas</h3>
<p>Since 1977, <a href="https://thrivemarket.com/brand/jarrow-formulas"target="_blank">Jarrow Formulas</a> has been developing supplements that range from minerals and probiotics to vitamins and enzymes. No matter which product you choose, each supplement has been verified by the brand’s scientific panel, which closely monitors FTC and FDA regulations in the industry.</p> 
<h3>Nordic Naturals</h3>
<p><a href="https://thrivemarket.com/brand/nordic-naturals"target="_blank">Nordic Naturals</a> got its start with cod liver oil, which the Norwegian founder couldn’t find when he moved to California to attend graduate school). Each supplement goes through a rigorous testing process before hitting shelves, and the brand also gives back to global health organizations.</p>  
<h3>Country Life</h3>
<p>Founded in Long Island, New York in 1971, <a href="https://thrivemarket.com/brand/country-life"target="_blank">Country Life</a> played a critical role in helping pass the 1994 Dietary Supplement Health and Education Act (DSHEA) and is known for becoming the first Certified Gluten-Free supplement brand in 2008.</p>  
<h2>Best Letter Vitamin Supplements</h2>
<p>From vitamin K to MK-7, here’s a look at some lesser-known vitamins.</p> 
<h3>Jarrow Formulas PS 100- Phosphatidyl Serine</h3>
<p>It’s a bit of a mouthful to pronounce, but <a href="https://thrivemarket.com/p/jarrow-formulas-ps-100-phosphatidyl-serine"target="_blank">phosphatidylserine</a> (which you can shorten to PS) is a natural phospholipid found in cell membranes. This concentrated form is soy-free and made without non-GMOs.</p> 
<h3>Nordic Naturals Vitamin D3 + K2</h3>
<p>Gluten-free and Non-GMO Project Verified, <a href="https://thrivemarket.com/p/nordic-naturals-vitamin-d3-k2-gummies"target="_blank">Nordic Naturals</a> offers the benefits of both D3 and K2 in one convenient gummy, which may help balance the levels of calcium and phosphorus in your blood.</p> 
<h2>Tips for Choosing the Right Vitamins</h2>
<p>Looking for the best vitamin supplements? Have a read through our guides to learn more about each nutrient you’re considering.</p> 
<h3>Where to Find Vitamin A</h3>
<p>One type of <a href="https://thrivemarket.com/blog/vitamin-a-everything-you-need-to-know"target="_blank">vitamin A</a> (retinol) can only be found in animal sources (like dairy milk and butter). The other type (beta carotene) is plentiful in lots of different vegetables.</p>  
<h3>How to Make DIY Vitamin C Gummies</h3>
<p>Getting your kids to take their vitamins is easy when you offer a <a href="https://thrivemarket.com/blog/easy-diy-raw-honey-vitamin-c-gummies-to-help-boost-your-immunity"target="_blank">homemade gummy</a>. A short list of ingredients (like grass-fed gelatin, raw honey, and vitamin C powder) makes easy work of this nutritious supplement.</p>  
<h3>Vitamin D3 Benefits</h3>
<p>If you aren’t getting enough daily sun exposure (news flash: many of us don’t), you may benefit from taking vitamin D3 supplements. <a href="https://thrivemarket.com/blog/vitamin-d3-benefits"target="_blank">Here’s our guide</a> to “the sunshine vitamin.”</p>

Buy other letter vitamins online at Thrive Market. Save time and money, and get the best dietary supplements delivered. Free shipping on most orders!

Buy Other Letter Vitamins Online

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