What foods are high in vitamin K?

Foods High in Vitamin K

The highest dietary sources of vitamin K are dark green leafy vegetables (particularly spinach with 145-1027 μg per cup depending on preparation), followed by certain cooking oils (soybean oil with 193 μg/100g and canola oil with 141 μg/100g), with moderate amounts in broccoli, soybeans, pickles, lettuce, and salad dressing. 1

Primary Vitamin K Sources by Category

Dark Green Leafy Vegetables (Highest Content)

• Spinach is the most concentrated source, containing 144.9 μg vitamin K per cup when raw, but dramatically increases to 1027.3 μg per cup when frozen and cooked 1
• Green leafy vegetables constitute the major dietary source of vitamin K overall 2
• Other green vegetables include lettuce, which is commonly consumed 1

Cooking Oils and Fats (Very High Content)

• Soybean oil contains 193 μg vitamin K/100g and is commonly used in fast food restaurants 1
• Canola oil contains 141 μg vitamin K/100g 1
• Corn oil is notably low at only 2.91 μg/100g, making it a safer alternative for those needing to limit vitamin K 1

Vegetables and Plant Foods (Moderate Content)

• Broccoli is a commonly consumed vitamin K source 1
• Soybeans contain significant amounts 1
• Pickles are a notable source 1
• Salad dressing (due to oil content) 1

Processed and Fast Foods (Variable but Potentially High)

• Fast foods can be significant sources due to soybean oil used in preparation 1
• Olestra potato chips contain 347 μg vitamin K/100g chips 1
• Processed foods vary widely depending on the oils used in production 1

Vitamin K2 (Menaquinone) Sources

Fermented and Animal Products

• Fermented cheeses are a major source of vitamin K2, as bacterial cultures synthesize menaquinones during fermentation 3
• Full-fat dairy products, especially fermented varieties like yogurt and cheese 3
• Animal products including meat, eggs, and poultry contain vitamin K2 (MK-4) 4, 5
• Chicken eggs and meat products (ham, chicken) have the highest MK4 content 5

Important Clinical Distinctions

Vitamin K1 vs K2

• Vitamin K1 (phylloquinone) is found primarily in green leafy vegetables, cruciferous vegetables, asparagus, prunes, peas, and parsley 3, 6
• Vitamin K2 (menaquinones) are mostly of bacterial origin and introduced through fermented cheeses and animal products 4, 6

Preparation Methods Matter

• Frozen vegetables that are cooked contain dramatically more vitamin K than fresh raw vegetables (spinach increases from 145 μg to 1027 μg per cup) 1
• This is a critical consideration for patients on warfarin who need consistent vitamin K intake 1

Practical Dietary Modifications

For Patients Needing to Limit Vitamin K

• Switch from canola or soybean oil to corn oil (2.91 μg vs 141-193 μg/100g) 1
• Use fresh instead of frozen green vegetables 1
• Read snack food labels carefully, particularly for Olestra-containing products 1
• Reduce fast food consumption due to soybean oil use 1

For Patients on Warfarin

• Consistency in vitamin K intake from week to week is more important than complete avoidance 1
• Develop a mutual plan with minimal dietary changes that maintains stable intake 1
• Note that 68% of warfarin users report being advised to avoid vitamin K-rich foods, which results in 35-46% lower vitamin K intakes, but current recommendations favor stable rather than restricted intake 7

Common Pitfalls to Avoid

• Do not advise complete avoidance of vitamin K-rich foods for warfarin patients, as this contradicts current evidence favoring stable, consistent intake 1, 7
• Be aware that commercial infant formulas contain vitamin K (8-16 μg/100 kcal) while breast milk contains virtually none (0.3 μg/100 kcal), which affects warfarin management in infants 1
• Recognize that the same vegetable can have vastly different vitamin K content based on preparation method (raw vs frozen/cooked) 1