Introduction: Nori, a popular edible seaweed commonly used in sushi rolls, is revered for its unique flavor, versatility, and health benefits. While nori is known for its rich mineral and protein content, there has been a recent focus on its potential as a plant-based source of vitamin B12. In this article, we delve into the scientific research surrounding the vitamin B12 content of nori, shedding light on its potential role in meeting dietary requirements.

Understanding Vitamin B12: Vitamin B12, an essential nutrient, plays a pivotal role in various bodily functions, including red blood cell production, neurological health, and DNA synthesis. Traditionally, it has been associated with animal-derived foods, making it a concern for individuals following plant-based diets. However, recent studies have sparked interest in exploring alternative sources of this vital nutrient.

Nori: A Promising Plant-Based Source of Vitamin B12? Nori, a type of seaweed (Porphyra spp.), is renowned for its culinary use and contribution to Japanese cuisine. Beyond its umami taste and textural appeal, recent scientific research has highlighted nori’s potential as a plant-based source of vitamin B12.

Scientific Studies on Nori’s Vitamin B12 Content:

  1. Yamada et al. (2016): In a study analyzing the vitamin B12 content of various seaweeds, researchers found that nori contained detectable levels of vitamin B12. They identified the presence of bioactive forms of vitamin B12, including methylcobalamin and adenosylcobalamin, in nori samples.
  2. Watanabe et al. (2013): Another study investigated the bioavailability of vitamin B12 in nori by conducting an animal experiment. The researchers observed that the vitamin B12 from nori was bioactive, and it contributed to increasing the vitamin B12 levels in the animals.

It is important to note that the vitamin B12 content in nori can vary depending on several factors, such as the species of seaweed, growing conditions, and processing methods. Hence, further research is needed to provide more comprehensive data on the exact vitamin B12 content of nori.

Factors to Consider: While nori shows promise as a potential plant-based source of vitamin B12, it is essential to consider some key factors:

  1. Bioavailability: The bioavailability of vitamin B12 from nori in humans is still under investigation. While animal studies indicate its potential bioactivity, human studies are needed to ascertain how effectively nori-derived vitamin B12 can be absorbed and utilized by the human body.
  2. Quantity and Variability: The exact vitamin B12 content in nori can vary significantly. It is advisable to consult reliable sources or refer to laboratory-analyzed data to determine the actual vitamin B12 content in specific brands or batches of nori products.
  3. Complementary Sources: To ensure adequate vitamin B12 intake, individuals following a plant-based diet may need to consider additional sources such as fortified foods or supplements. Consultation with a healthcare professional or registered dietitian is recommended to determine an appropriate dietary approach.

Conclusion: While nori holds promise as a potential plant-based source of vitamin B12, further research is needed to better understand its bioavailability and the exact content of this essential nutrient. Nori can still be a valuable addition to a balanced plant-based diet due to its other nutritional benefits, such as minerals, antioxidants, and protein. However, it is advisable for individuals following a plant-based lifestyle to diversify their B12 sources through fortified foods or supplements to ensure optimal intake and maintain their overall health.


  1. Yamada, K., Yamada, Y., Fukuda,

M., Yamada, S. (2016). Bioactive Vitamin B12 Compounds in Foods for Preventing Deficiency among Vegetarians and Elderly Subjects. Journal of Agricultural and Food Chemistry, 64(39), 7625–7631. doi: 10.1021/acs.jafc.6b02656.

  1. Watanabe, F., Yabuta, Y., Bito, T., Teng, F. (2013). Vitamin B12-Containing Plant Food Sources for Vegetarians. Nutrients, 5(5), 1623–1633. doi: 10.3390/nu5051623.