Vitamin K Foods: Best Sources and What You Need to Know

When you think about vitamins, you probably think of vitamin K, a fat-soluble nutrient essential for blood clotting and bone health. Also known as phylloquinone (K1) or menaquinone (K2), it doesn’t get much attention—but without it, even a small cut could become dangerous. Unlike vitamin C or D, your body doesn’t store vitamin K well, so you need it regularly from food. And no, supplements aren’t always the answer—most people get enough from their diet if they eat the right things.

There are two main types of vitamin K you need to know about. vitamin K1, the form found mostly in leafy green vegetables is what your liver uses to make clotting proteins. vitamin K2, produced by bacteria and found in fermented foods and animal products, helps direct calcium to your bones instead of your arteries. Both matter. If you’re on blood thinners like warfarin, your doctor watches your vitamin K intake closely because it directly affects how the drug works. Too much can make the medicine less effective; too little can raise your risk of bleeding.

You don’t need to take a pill to get enough. Just eat a few key foods daily. vitamin K foods like kale, spinach, broccoli, and Brussels sprouts are top sources of K1. A single cup of cooked kale gives you over 1,000 micrograms—more than double your daily need. K2 shows up in natto (fermented soybeans), cheese, egg yolks, and chicken liver. Most people don’t eat enough of these, especially if they avoid dairy or fermented foods. If you’ve had stomach surgery, take antibiotics often, or have digestive issues like Crohn’s or celiac disease, your body might not absorb vitamin K well—even if you eat it.

It’s not just about avoiding bleeding. Low vitamin K levels are linked to weaker bones and higher fracture risk, especially in older adults. That’s why some studies connect long-term low intake to osteoporosis. And while most people don’t get sick from lack of vitamin K, newborns are at risk—so they get a shot at birth. If you’re wondering why your doctor asked about your greens before prescribing blood thinners, now you know. It’s not about being healthy—it’s about keeping your medication working right.

What you’ll find in the posts below isn’t a list of supplements or pills. It’s real, practical info from people who’ve dealt with medication interactions, aging bodies, and nutrient gaps. You’ll see how vitamin K connects to drugs like warfarin, how liver and kidney changes affect absorption, and why some people need to watch their diet more than others. No fluff. Just what works—and what doesn’t—when it comes to getting enough of this quiet but critical nutrient.