Edible Seaweed and Vitamin K

Publication Date: 
Sun, 06/01/2014
By: Alere Staff


Some species of seaweed are famous delicacies and are also considered a common source of food in many cultures. Some well-known edible seaweed types include nori, agar, kelp, carrageen moss, and dulse. Compared to the plants from land and animal-based foods, seaweed is rich in some healthy vitamins and minerals such as, dietary fiber, omega-3 fatty acids, essential amino acids, iodine, and vitamins A, B, C, and E.1

Compounds taken from seaweed have shown different biological benefits, such as antibacterial activity, antioxidant possibilities, anti-inflammatory properties, anti-coagulant activity, and anti-viral activity. Seaweed has important applications in a range of products in food, pharmaceuticals and cosmetics.2

There are three main types of seaweed based on the color of the pigment: brown, red, and green. Within these categories of seaweed, there are dozens and dozens of edible seaweed varieties. Some common edible seaweed types include:

  • Nori (laver) – dried layer of seaweed pressed into thin sheets and used as a seasoning or as a wrapper for sushi. Vitamin K content = 0.2 mcg per 1 Tablespoon.3
  • Agar – often used as a gelatin substitute with strong thickening properties. Vitamin K content = 3.6 mcg per 1 Tablespoon.3
  • Kelp – most readily available type of seaweed with some popular ones being kombu and wakame and often dried and used in soups. Vitamin K content = 3.3 mcg per 1 Tablespoon.3
  • Dulse – red seaweed often shredded and dried, but can also be eaten fresh and sautéed similar to land vegetables.
  • Carrageen moss (Irish moss) – most often eaten fresh and cooked to a pudding-like dessert. Vitamin K content = 0.2 mcg per 1 Tablespoon.3

For more information about the amount of vitamin K in the foods and beverages you consume, check out our Vitamin K Finder. It is important to talk with your doctor about starting any new foods because they can interact with your warfarin, so please keep this in mind when planning your next meal.

  1. Rajapakse N, Kim SK. Nutritional and digestive health benefits of seaweed. Adv Food Nutr Res. 2011;64:17-28.
  2. O’Sullivan, L., et al. Prebiotics from Marine Macroalgae for Human and Animal Health Applications. Mar Drugs. 2010; 8(7): 2038–2064.
  3. U.S. Department of Agriculture, Agricultural Research Service. 2004. USDA National Nutrient Database for Standard Reference, Release 17. Nutrient Data Laboratory Home Page, http://www.nal.usda.gov/fnic/foodcomp.