Why do Vitamin K levels vary in the same foods?

Why does the Vitamin K level go higher after the broccoli is cooked? Raw chopped it is 92.5mcg and cooked chopped is 220.2. Also if we keep our RDA of Vitamin K at 80mcg does that mean our INRs won't change?

The Health meets Food Team Says...

The difference occurs not because there is a change in the amount of Vitamin K, but because the volume of cooked broccoli is smaller than when it is raw.

The results that the USDA gives for cooked foods are measured after the food is cooked. Cooked, chopped broccoli takes up perhaps half of the volume that raw broccoli does. This is more obvious with ingredients like mushrooms or spinach, which lose even more volume when cooked.

On the other hand, there is no evidence that cooking has an effect on Vitamin K. If you have half a cup of broccoli and cook the broccoli, it will still contain the same amount of Vitamin K as it did before you cooked it.

While there can be a lot of factors that have an effect on the action of warfarin, consuming a consistent amount of Vitamin K each day will help keep your INR results more stable.

Thanks for writing.