Plus, what to know about the health benefits—and risks—associated with the food.

By Madison Yauger
January 21, 2021
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Sushi isn't just a delicacy, it's practically an art form. With humble roots, starting as a way to preserve fish in Japan, this cuisine has become an immensely popular and sophisticated dish across America.

At its baseline, sushi seems like a healthy, nutritious meal: rice, veggies, fresh fish—but past that, there are many different variations as to how sushi can be prepared and which ingredients are used. Here, registered dietitians weigh in on the health benefits of sushi, and how to get the most out of your order.

Real quick: What exactly is sushi?

Sushi is a collection of rice, vegetables, and cooked or raw fish wrapped up in a roll of seaweed. There are typically three types of sushi, according to Comprehensive Reviews in Food Science and Food Safety, and they include: nigiri, maki, and temaki. Nigiri is raw fish, salmon eggs, cooked shrimp, or sliced egg on rice. Maki is rolled sushi. Temaki, or a handroll, is sushi rolled by hand into a cone shape. The variance of ingredients in these types of sushi is where the question of health begins to surface.

"To make sushi, [vinegar-saturated] rice is hand-molded and topped with raw fish or other seafood. Vinegar is added to cooked rice to achieve a pH of 4.6 or less, depending on the chef's preference; some chefs like to add a little sweetness to their rice to make it more palatable, [and] that's why other ingredients such as sugar and/or salt may be included," Ella Davar, RD, CDN, a registered dietician integrative nutritionist and certified health counselor based in Manhattan, tells Health.

Davar explains that "in the rolled variant (maki), a special bamboo mat is used and nori (a thin sheet of prepared seaweed) is wrapped around the rice and fillings such as [egg], avocado, mango or cucumber." She says that "nori contains significant amounts of vitamins A, B1, B2, B6, B12, C, niacin, and folic acid," noting that "the vitamin C content can decrease by drying the product."

While sushi has many healthy elements, its preparation and seasoning can take away from the overall nutrition. For example, "rolls dipped in tempura and fried [and] then covered with a creamy sauce will not be the same as those wrapped solely in nori and packed with fish, rice and vegetables," Marisa Moore, RDN, a registered dietitian nutritionist based in Atlanta, tells Health. 

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Which types of sushi are the healthiest?

In terms of health and longevity, the Japanese diet has significantly contributed to longer lifespans, and that's in part due the fish they eat, many of which are high in EPA and DHA fatty acids, and are found in different types of sushi. If you're looking for what to order, Davar recommends "nigiri (thin slices of raw fish topped over small balls of vinegared rice) and sashimi (thin slices of raw fish)", alongside "a salad and side of cooked vegetables, which [are great sources] of fiber and micronutrients."

"The idea is to see more colors from various fish and veggies and less white color of cooked vinegared rice," says Davar. "Also, in addition to the regular rice wrapped roll, I like to order "Naruto-style" which is a roll wrapped in cucumber. It is fun, crunchy, and makes a great healthy option in addition to traditional sushi menu options," she says. However, if you're gunning for rolled sushi, try to use healthier types of fish like salmon and mackerel (which are low in mercury). Avoid high-sodium soy sauce and go for other healthy flavor enhancers like wasabi or pickled ginger (gari). 

What are the health benefits of sushi?

The various combinations of different vegetables and fish have enriching benefits—especially with additives like wasabi and picked ginger—but what exactly do all those flavorful ingredients do for your body?

It may help improve gut health

"A major contributor to Japanese health is the gut microbiota, which thrives on fermented vegetables and foods like bok choy, seaweed, mushrooms, kimchi, natto and tofu," says Davar. "Dietary fiber provides prebiotics and a good nutritional environment for beneficial microbes and helps cleanse the gut of the harmful substances that unhealthy bacteria produce," she adds.

It can strengthen your immune system

"Research has also shown that wasabi, the unique flavorant used to spice up and disinfect raw fish in sushi, has significant health benefits and helps strengthen the immune system," says Davar. "Wasabi is rich in beta-carotenes, glucosinolates, and a range of isothiocyanates, which have antibacterial properties and help mitigate microbial elements or latent pathogens." She also notes that wasabi has been known to kill some forms of E. coli and Staphylococcus bacteria.

It can help improve your heart health

"Salmon [and] mackerel are excellent sources of protein in addition to DHA omega-3 fatty acids which may reduce the risk of coronary heart disease (as well as support brain health and memory retention)," says Davar. A U.S. Food and Drug Administration (FDA) report supported these findings stating there is limited but credible evidence that the DHA found in oily fish can reduce blood pressure and lower the risk of hypertension, two common risk factors of developing coronary heart disease.

It may help your body's natural detoxification process

The nori most commonly used to make sushi, is extremely nutritious. It has 10 times as many vitamins as spinach, and contains 30 to 50% protein and merely 0.1% sugar, according to Davar. "Other beneficial seaweed include kelp, wakame, kombu and bladderwrack, followed by red seaweed (which includes nori), dulse and Irish moss, and finally green seaweed. [These] are high in iodine and help to support natural detoxification processes in the liver," she says.

What are the health risks of sushi?

Sushi can be a healthy option, but this delicacy is not without its faults, and with the benefits come a couple of risks to be considered as well.

It can lead to high sodium intake

Part of what makes sushi so flavorful is the high concentration of salt. The rice, fish and even seaweed all come into contact with salt during the preparation process, and that's before adding high-sodium additives like soy sauce. According to the Harvard T.H. Chan School of Public Health, the main problem with salt is that your kidneys have trouble keeping up with excess sodium in the blood. Your body tries to dilute the sodium and retains more water, which increases your overall blood volume. This leads to your blood vessels working overtime to pump all of that blood, and that pressure can stiffen blood vessels, resulting in high blood pressure, heart attack, stroke, and even heart failure. Key takeaway? Take it easy with the salt.

It adds more refined carbs to your diet

White rice is a big part of sushi and unfortunately, it's a refined carbohydrate, meaning it includes sugars and has been stripped of all of its nutrients. "The difference between commonly used white rice and less processed brown rice is that after processing rice, grain is stripped off of the highly beneficial outer husks, bran and germ (which is the fiber or the roughage that contributes to healthy gut flora and serves as a prebiotic)," Davar says. Studies have shown an increased intake of refined carbs have contributed to the prevalence of type 2 diabetes in the U.S., and white rice specifically has a high sugar content which can lead to overeating due to spikes in blood pressure and insulin levels.

It may add unsafe levels of mercury to your diet

According to the Natural Resources Defense Council, the top fish you should avoid due to their high mercury content are King mackerel, marlin, orange roughy, shark, swordfish, tilefish, ahi tuna, and bigeye tuna. "Tuna has gotten a bad reputation due to [its] high mercury content, however that depends on the type of tuna," says Davar. Experts recommend swapping ahi (yellowfin) and bigeye tuna, which accumulates the most mercury over its lifetime, for a light tuna or skipjack tuna. If you're willing to skip tuna altogether, you can opt for lower-mercury fish and shellfish like eel, salmon, crab and clam.

It puts you at risk for foodborne illness

Preparation of food can make a huge difference in terms of health and food safety. Most cooking requires high heat to eliminate food contaminants like pathogens, but with sushi, this step doesn't happen. Davar notes that one of the biggest hazards of consuming uncooked, undercooked, or frozen seafood, are the parasites, which can grow naturally in many animals and be transmitted to and cause illness in humans. "The FDA recommends that anyone with reduced autoimmunity illnesses and certain conditions, like pregnancy and old age, follow safe seafood practices and stay away from eating sashimi, raw fish, and sushi," says Davar. 

In order to avoid the risk for foodborne illness when dealing with raw and undercooked fish, Moore suggests that you "always purchase your sushi from a reputable restaurant, or if you're making it yourself, seek out a fishmonger that provides sushi grade fish that's been handled and sold specifically for sushi."

What do the experts recommend when choosing sushi?

Plainly, some elements of sushi are fabulous for your health, and some elements are less than stellar. As Moore puts it, "Not all sushi is created equal, and it can vary from place to place." That being said, if you absolutely love sushi, there are ways to make it healthier.

"Instead of relying on names, take a look at what's inside [the sushi] as well as the sauces," says Moore. "Go for rolls with your favorite seafood, vegetables such as cucumber and carrots, and add creaminess from avocado."

In addition to recommending sashimi and nigiri, Davar also suggests, "when ordering sushi rolls, [ask] for "less rice" to prevent blood sugar spikes due to high carbohydrate load from white rice and sweetener used to make it."

"Generally speaking, with salmon, tuna and other seafood as the base, sushi can be a great option. To round out the meal, consider adding a salad or steamed edamame from the menu for a filling meal," adds Moore. Essentially, load up with veggies and lower your rice intake, and you'll be good to go.

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