How Eating Fish Can Boost Your Immune System and Keep Viruses Away

WASHINGTON — Heading back into the cold and flu season is extra anxious this year. Now, more than ever, people are looking for ways to “boost” or support their immune systems, according to Seafood Nutrition Partnership.

“Nutrients, the things we eat, are a very important part of how our immune system functions in addition to things like physical activity and not smoking,” said Dr. Philip Calder, professor of nutritional immunology at the University of Southampton and author of a recent peer-reviewed study, “Nutrition and immunity: lessons for COVID-19.” “The immune system is central to protection against infection. In the past 18 months, weak immune systems have been exposed as a major public health challenge.”

Good nutrition is essential to supporting a strong immune system, and if there is one food that packs a punch of a wide spectrum of vitamins and minerals, it is seafood. “Seafood is an excellent source of immune-supporting micronutrients, some of which, like Vitamin D, are really hard to get from other foods,” said Calder at the Seafood Nutrition Partnership’s 2021 State of the Science Symposium.

Data from the NIH-AARP Diet and Health Study of more than 420,000 people show eating seafood reduced respiratory deaths by 20 percent. In fact, higher fish and omega-3 fatty acid intakes were significantly associated with lower total mortality.

Both fish and shellfish provide essential nutrients to the body that keep immune health functioning properly. Here are some key nutrients found in a variety of seafood that work together to support antiviral immunity, according to the Seafood Nutrition Partnership, which has an Eat Seafood America! initiative to help Americans stay healthy through the pandemic and beyond.

  • Omega-3s EPA and DHA – Omega-3s EPA and DHA found in seafood “are very important to the immune system,” Calder said. “They are also anti-inflammatory, that means they can reverse the harmful effects of the immune response. This is a really important effect in the context of immunity.” Fish with the highest omega-3 levels include salmon, herring, anchovies, oysters, sardines and trout. Here is a chart of seafood options that shows levels of omega-3 fatty acids.
  • B Vitamins – B vitamins such as B2, B6, and B12 all help keep the immune system working properly by regulating inflammation while promoting red and white blood cell development to keep the oxygen flowing while fighting against disease. Seafood, both fish and shellfish, have a variety of B vitamins.
  • Vitamin D – “Vitamin D controls the function of the immune system,” Calder said. D plays an important part in the innate antimicrobial (an agent that kills microorganisms) response, which helps keep the immune system functioning properly. “Perhaps the most important dietary source is fatty fish.”
  • Iron – Iron is essential in the activation and reproduction of immune cells. All shellfish is high in iron, but clams, oysters and mussels are particularly good sources.
  • Selenium – Selenium, which is often overlooked according to Calder, has a role in mitigating viral mutation. It is an antioxidant that helps to lower oxidative stress levels in the body, which in turn reduces inflammation and enhances immunity. All seafood has selenium; tuna, sardines, clams, halibut, and shrimp are all good options to consider.
  • Zinc – Zinc helps the immune system work properly and may help wounds heal. It’s found in cells throughout the body. It helps the immune system fight off invading bacteria and viruses. The body also needs zinc to make proteins and DNA, the genetic material in all cells. Shellfish like oysters, crab, and lobster are good sources of zinc. Zinc is found in fish like sardines, salmon, flounder, and sole.

No one food or supplement can prevent illness, but the immune system can be supported by including these key nutrients found in seafood on a regular basis.