Seaweed isn’t a plant; it’s an umbrella term for thousands of different marine algae. Seaweeds harvest sunlight to grow, but they don’t have roots, stems or leaves and they absorb nutrients directly from the seawater.
Seaweed has long been a diet staple in coastal communities, and recently it’s gotten more attention as a sustainable food source. There are dozens of edible species, including nori, often used to wrap sushi; wakame, typically found in soups and salads; and kombu, which gives dashi broth its deep umami flavor.
Here’s a look at seaweed’s considerable health benefits, plus ideas for how to prepare it from New York Times Cooking.
It’s great for your gut.
Seaweed of all types is rich in polysaccharides, long chains of sugar molecules that form the walls of plant and algae cells. Some of these molecules are too complex for humans to digest without the help of beneficial gut microbes. In turn, the polysaccharides help these microbes thrive.
Beneficial gut microbes also ferment polysaccharides into short-chain fatty acids, another group of molecules important to gut health, said Shelly Wegman, a clinical dietitian at University of North Carolina Rex Hospital. “These molecules actually fuel and repair the cells of the gut lining,” she said. Some research also suggests that certain short-chain fatty acids could decrease the risk of colorectal cancer.
It’s a complete source of protein.
Seaweed contains all nine essential amino acids, the building blocks of protein that the body uses to build its muscles and tissues. How much protein seaweed contains, however, depends on the variety. Scientists have found that, gram for gram, dried nori is up to 47 percent protein — more than chicken breast, proportionally speaking. Dried wakame is closer to 16 percent.
That said, considering that typical servings are small, you’re unlikely to get a meal’s worth of protein from seaweed alone, said Yvonne Yuan, an associate professor at Toronto Metropolitan University School of Nutrition. One sheet of nori, for example, has just 1 gram of protein.
It contains iron and vitamin B12.
Thanks to the mineral-rich seawater it grows in, seaweed has higher quantities of certain nutrients than are found in plants. Those include iron, which the body needs to carry oxygen to your organs, and vitamin B12, which is used to build and maintain healthy red blood cells and nerve cells. These nutrients are often lacking in plant-based diets, and seaweed can help fill that gap, said Ingrid Undeland, a professor of food and nutrition science at Chalmers University of Technology in Sweden.
Nutritional data on seaweed varies, but according to one analysis, five grams of dried nori (the amount typically found in a snack pack) can contain nearly 1.4 milligrams of iron — around 17 percent of the recommended daily amount for men and 8 percent for women (pregnant women need more). A sheet of dried nori has about 80 percent of the daily amount of vitamin B12.
Be aware that one mineral — iodine — can be present in overly high doses in some seaweed. The body uses iodine primarily to make thyroid hormone, but needs only trace amounts to do it (the daily recommendation is 150 micrograms). Fresh, foraged seaweed can have many times that amount, and some varieties may contain toxic quantities, Dr. Undeland said. Store-bought seaweed is typically blanched, which reduces iodine to safer levels. But even then, the amounts can be on the high side — one study reported that a meal of sushi and seaweed salad contained 231 micrograms.
“People who have any concerns about their thyroid should be cautious and talk to a dietitian” before they add more seaweed to their diet, Ms. Wegman said.
Ready to dive in?
You can find dried seaweed varieties in the international food aisle of most major grocery stores. Crunchy seaweed snacks can be equally nutritious, but be mindful of their sodium content, Ms. Wegman said.
If you want to be even more adventurous, look online or in specialty stores for fresh sea lettuce, which is particularly high in calcium and other micronutrients, Dr. Undeland said.
Here are recipes from NYT Cooking to get you started.
Simple Seaweed Salad
This classic Japanese side dish is dressed with soy sauce, vinegar and sesame oil. Wakame, the seaweed used for this recipe, is sold dried, so it can become a pantry staple.
Recipe: Simple Seaweed Salad
Creamy White Bean and Seaweed Stew With Parmesan
Kelp and kombu swap in for escarole in this play on white bean soup.
Recipe: Creamy White Bean and Seaweed Stew With Parmesan
Soy-Glazed Salmon Hand Rolls
In these make-at-home hand rolls, toasted sheets of seaweed offer a crackling contrast to the creamy avocado and crisp cucumber.
Recipe: Soy-Glazed Salmon Hand Rolls
One-Pot Creamy Brown Rice and Vegetables
Showering rice and vegetables with crumbled roasted seaweed snacks or furikake, a seaweed and sesame condiment, gives them a savory kick.
Recipe: One-Pot Creamy Brown Rice and Vegetables
Sesame-Soy Tofu Bowls
Cooking rice with seaweed makes each bite deeply flavorful. Here, it’s topped with tofu and cucumbers, but it’s a wonderful base for nearly anything.
Recipe: Sesame-Soy Tofu Bowls
The post How Healthy Is Seaweed? appeared first on New York Times.
