Vitamin K1 in Plant Based Foods

The Adequate Intake (AI) is 90µg/day for women and 120µg/day for men — there is no RDA for vitamin K1. A single cup of raw kale provides well over the AI. A handful of parsley (about 10g) delivers over 160µg. Plant based eaters who include even modest amounts of leafy greens consistently meet or exceed the adequate intake with ease.

Vitamin K1 (phylloquinone) is found almost exclusively in green leafy vegetables and is the primary dietary form on plant based diets. Vitamin K2 (menaquinone) is produced by bacteria in fermented foods like natto (fermented soybeans), tempeh, and sauerkraut — K2 content varies dramatically. The body can convert some dietary K1 to K2, though the efficiency is modest. For plant based eaters, K1 from leafy greens is the reliable, consistent source.

Yes, absolutely. Plant based diets are the richest dietary source of vitamin K1. Leafy greens — kale, spinach, collard greens, Swiss chard, parsley — are unequivocally the highest-concentration sources. A plant based eater who includes even modest servings of cooked or raw leafy greens easily meets the adequate intake. This is one nutrient where plant based diets have a decisive advantage over omnivorous diets.

Vitamin K1 is fat-soluble, not water-soluble, so it is remarkably heat-stable. Boiling leafy greens causes minimal K1 loss — most is retained. In fact, cooking increases the bioavailability of vitamin K1 slightly by releasing it from plant cells. Cooking also reduces volume, making it easier to consume larger quantities of greens. Both raw and cooked greens deliver abundant vitamin K1; the best approach is to eat both forms regularly.