Seaweed Nutritional Facts

Dried seaweed is a nutritional powerhouse.  Sea vegetables are known to contain most, if not all, of the 24 minerals and trace elements required for your body's physiological functions, some in quantities greatly exceeding those of land plants.  They contain significant levels of vitamins, including the B vitamins, Vitamin A, and Vitamin C.  Their protein content ranges from 10% to almost 40%, and they contain all or most of the essential amino acids required by humans.  They’re low in fat and high in fiber; two qualities that make them healthy for the heart.  And then, of course, there’s iodine.  Sea vegetables are one of the highest natural sources of dietary iodine, even when eaten in small quantities.

Below are two tables showing levels of selected nutrients found in our eight species of whole leaf sea vegetable, seaweed blends, and in Kelp Krunch.  Milled sea vegetables have the same nutritional composition as the whole leaf from which they were milled.  For example, dulse flakes have the same nutritional composition as whole leaf dulse. The levels in these tables are provided as “amounts per 100g” because this is how the information is normally presented for food industry specifications.  It also makes it easier to compare levels between species and products.  You can use this table to calculate how much of any specific nutrient you're getting in a specific serving size.  All you need is a calculator and a simple formula: divide the level of the nutrient found in the nutrients per 100g table by 100 to get the level per gram, and then multiply by the number of grams in your serving. Just remember, it's impossible to know the exact level of any nutrient in sea vegetables because nutrients vary between season, age, location, and other factors.  Also, 100 grams is not a serving size!  Serving sizes of sea vegetables are much smaller than that. If you scroll down the page past the tables you will find more information on serving size, as well as on specific nutrients.

The levels provided in these tables represent average compositions determined through various published research articles and our own testing.  For some species there’s no published data for certain nutrients and we have not yet tested for those nutrients.  When that’s the case, it’s indicated by “ND” (No Data).  Also, it’s important to keep in mind that sea vegetables are wild marine plants, and their nutritional composition is known to vary due to naturally occurring fluctuations in the plants. These fluctuations may be due to location, season, tidal flows, ocean temperatures, weather patterns, and other factors. The values presented here are not absolutes, and we believe the whole plants provide more than the sum of their parts. (You may double click on the table in order to view larger.)

Seaweed Nutritional Facts By Species

Serving Size

To paraphrase an old saying, oftentimes good things come in small portions.  This is definitely true of sea vegetables.  You don’t have to eat a lot to get the most of their flavor and nutrition.  Even in Japan, where about one-third of the adult population eats seaweed almost every day, the average daily intake is only about 4-7 grams, usually over the course of 2-3 small servings eaten throughout the day.  In the US, the FDA defines a serving size as the amount of food customarily consumed (i.e., typically eaten) in one sitting for that food.  The FDA often refers to serving size as the “Reference Amount Customarily Consumed”, or RACC. The serving size is required information on nutrition facts labeling because it informs consumers about the nutritional value of their food in a quantifiable fashion.  The serving size shouldn’t be interpreted as the amount one is supposed to eat, but rather as the amount that most people ordinarily eat.  For dried edible seaweed, the FDA considers 5g to be the RACC. 

The below table shows the serving size for most Maine Coast Sea Vegetable products, along with levels of the three essential minerals required on the nutrition label, plus iodine (nutritional values are rounded to nearest whole number).  You’ll see that the serving size for some of our milled products is smaller than the FDA RACC of 5 grams for seaweed, whereas for whole leaf products it’s larger.  We’ve learned through experience and from our customers that how much people eat very much depends on the product form and how it’s used.  Sea vegetable flakes, granules and powders are usually used in small amounts to add flavor and nutrition to such things as soups, dips, or smoothies.  Whole leaf sea vegetables, on the other hand, may be eaten as snacks or used as ingredients in salads or casseroles, much as one might add arugula or other greens to a mixed salad, or spinach to a lasagna.  

Typical Sea Vegetable Serving Sizes Showing Essential Minerals and Iodine Per Serving