Raw fish has been a staple food in human culinary history. Japan, for one, has elevated its traditional sushi and sashimi to global gastronomic indulgences. Many people who may want to eat raw fish, however, harbour concerns about its health such as allergies or infections.
Take the case of Akash Sarkar, 30, a communication professional from Bengaluru, who has a long history of seafood allergies. Initially hesitant to try sushi out of fear of his allergies, Sarkar gave it a shot three years ago and has not looked back. “I’m a big fan of sushi and often enjoy sushi nights with my partner,” he says.
Low-calorie and nutrient-dense
While their flavour mainly gets people hooked on such delicacies, their high nutritional values cannot be ignored. Yet, all that may come with the risk of a bacterial or parasitic infection.
Dr Soumita Biswas, chief nutritionist at Aster RV Hospital in Bengaluru, says raw fish contains high levels of omega-3 fatty acids like eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which are essential for health.
According to a study published in the Journal of American Heart Association in 2015, people who ate fatty fish containing Omega 3 fatty acids a few times a week had a nearly 50 per cent lower risk of dying from coronary heart disease and a 25 per cent lower risk of dying from a heart attack compared to those who did not consume any fish.
“Raw fish is typically lower in fat compared to cooked fish and an excellent source of high-quality protein and omega acids, making it an excellent option for people trying to maintain a healthy weight and also build muscles,” says Dr Biswas.
Source of food-borne infections
The US Centers for Disease Control and Prevention recommends against eating these seafood raw or undercooked: fish, shellfish, sashimi, sushi and ceviche. According to it, they can increase the risk of foodborne infections like vibrio, salmonella, listeria and norovirus.
A 2019 study published in the Journal of Food Protection found that raw fish products, particularly sushi, can cause outbreaks of foodborne illnesses.
“Raw fish contains bacteria, viruses, and parasites that cause foodborne illness,” says Aisvarya Madhavan, nutrition coach, HealthifyMe, Chennai. “Fish tapeworms are transmitted to people who eat raw or undercooked freshwater or sea fish that spawn in these water bodies.”
Sonia Velarsan, specialist in nutrigenomics and onco-nutrition, the University of Trans-Disciplinary Health Sciences and Technology, Bengaluru, says tuna, salmon and swordfish that are often used in raw fish cuisines can contain high levels of the mercury, which is especially harmful to pregnant women and children.
Allergy and digestion
Dr Abhishek Vishwakarma, resident doctor, Department of Pharmacology, All India Institute of Medical Sciences, Patna, says that consuming raw fish can cause allergic reactions such as hives, diarrhoea and fever.
“Raw fish purchased from local or unhygienic market places can be contaminated. When consumed, it can cause allergy, food poisoning and illness,” Dr Vishwakarma adds. “Allergy can sometimes stay lifelong and flare whenever one consumes fish raw.”
A study published in the Journal of Allergy and Clinical Immunology reveals that raw fish can cause allergic reactions in some people, particularly those with a history of seafood allergies.
Dr Vishwakarma also says some people may have a problem digesting raw fish. Stomachache, diarrhoea and nausea are linked with consumption of raw fish. People facing such digestive issues should quickly consult a doctor.
Nevertheless, it is possible to savour the flavours of raw fish dishes by taking precautions to reduce their health risks.
Sarkar, who worked around his allergy, says he frequents two places where he trusts hygiene and quality, apart from taste.
“I never had any ailment after consuming the sushi [at these places,]” he adds. “I will enjoy my sushi while being mindful of the place from where I am eating.”
Dr Biswas and Velarsan list some ways to reduce the risk of infections.
- FROZEN WELL: Freezing fish for a week at -4°F (-20°C), or for 15 hours at -31°F (-35°C) effectively kills parasites. But keep in mind that some household freezers may not get cold enough. Never leave fish out of the refrigerator for more than one or two hours. Bacteria multiply quickly at room temperature.
- TRUSTED SOURCE: It is essential to purchase raw fish from a reliable source to ensure that it is fresh and safe to eat.
- FRESHNESS: Raw fish should have a mild, fresh smell, and firm, glossy flesh. If the odour is strong and fishy, or the flesh is soft and discoloured, it should be avoided.
- HAND HYGIENE: Clean your hands after handling raw fish in order to avoid contaminating the food you handle afterwards.
- KITCHEN AND UTENSILS: Kitchen utensils and food preparation surfaces should be thoroughly cleaned to avoid cross-contamination.
- REFRIGERATE: Never leave fish out of the refrigerator for more than one or two hours. Bacteria multiply quickly at room temperature.
- BE SAFE THAN SORRY: And lastly, if you are not sure about the safety of the raw fish, cook it to the right temperature to kill any potentially harmful bacteria.
