Eat Fish Often? A Minnesota Guide to Eating Fish - EH: Minnesota Department of Health

Eat Fish Often? brochure cover pageEat Fish Often?
A Minnesota Guide to Eating Fish

Cover Image of PDF version:
Original batik by Sue Duda, Minocqua, Wisconsin

PDF version of this webpage formatted for print:
Eat Fish Often? A Minnesota Guide to Eating Fish (PDF),
April 2017

You already know that Minnesota is the Land of 10,000 Lakes and some excellent fishing. But how much do you know about the fish that you eat?

Eating fish 1 to 2 times a week has health benefits for people of all ages. Fish is a great source of lean protein with plenty of vitamins and minerals. Fish are a natural source of omega - 3 fatty acids - a good kind of fat.

However, any fish (store-bought or sport-caught) could contain contaminants such as mercury or PCBs that could harm human health—especially the development of children and fetuses.

What to do?

The benefits of eating fish outweigh the risks when eating fish low in mercury and other contaminants.

Eat fish! Follow the recommendations in this brochure to prevent mercury and other contaminates from building up in your body. Contaminants take time to leave your body so spread out your fish meals over time.

Tips for reducing contaminants in fish

You can't see, smell or taste the mercury or PCBs in fish. That's why it's important to know which fish are safer than others to eat. Larger fish, older fish and fatty fish have higher amounts of contaminants. Fish that feed on other fish—such as walleyes, northern pike and bass—have the highest amounts of mercury in their meat.

Remember the following tips when eating fish:

  1. Eat smaller, younger fish.

  2. Eat more panfish (sunfish, crappie) and fewer predator fish (walleyes, northern pike, lake trout).

  3. Trim skin and fat, especially belly fat. Also, eat fewer fatty fish such as carp, catfish and lake trout. PCBs build up in fish fat. For instructions on cleaning and cooking fish properly, see: Clean and cook fish Properly to deal with contaminants

Safe Eating Guidelines

The following Safe Eating Guidelines (provided in the two tables below) are based on mercury or PCB levels measured in fish throughout Minnesota and on levels of mercury found in commercial fish. Not all waters in Minnesota have been tested for contaminants in fish. But the Safe Eating Guidelines can be used for both tested and untested waters.

In addition to these general Safe Eating Guidelines, the Minnesota Department of Health also provides specific advice for lakes and rivers that have been tested.

For specific lake and river advice, see:

Guidelines for men, and for women not planning to become pregnant

Fish Caught in Minnesota

Kind of fish you eat How often can you eat it?*
Sunfish, crappie, yellow perch, bullheads unrestricted
Walleyes, northern pike, smallmouth bass, largemouth bass, channel catfish, flathead catfish, white sucker, drum, burbot, sauger, carp, lake trout, white bass, rock bass, whitefish, other species 1 meal a week

Commercial Fish

Kind of fish you eat How often can you eat it?*
Limit the following species: shark, swordfish, tile fish, king mackerel 1 meal a month

*In general, adults who eat fish just during vacation or one season can eat fish twice as often as recommended in these guidelines.

Pregnant women, women planning to become pregnant and children under age 15

If you are pregnant, planning to become pregnant, breastfeeding or have children under age 15, you and your children are more sensitive to contaminants. You need to be more careful about the kinds of fish you eat and how often you eat fish. Visit ChooseYourFish.org for more information.

Fish from some Minnesota lakes and rivers have been found to have higher levels of mercury or PCBs. If you eat certain fish from these waters, you should eat it less often than the guidelines below. For further information on restrictions for eating fish from specific Minnesota lakes and rivers, see:

Guidelines for Fish Caught in Minnesota
for pregnant women, women planning to become pregnant and children under age 15

Kind of fish you eat How often can you eat it?*
Sunfish, crappie, yellow perch, bullheads 1 meal a week

AND

Kind of fish you eat How often can you eat it?*
Walleyes, northern pike, smallmouth bass, largemouth bass, channel catfish, flathead catfish, white sucker, drum, burbot, sauger, carp, lake trout, white bass, rock bass, whitefish, other species 1 meal a month
Muskellunge Do not eat.

Guidelines for Commercial Fish
for pregnant women, women planning to become pregnant and children under age 15

Kind of fish you eat How often can you eat it?*
Shark, swordfish, tile fish, king mackerel Do not eat.
Other commercial species, including canned tuna See MDH's brochure, "Choose Your Fish (PDF)"

*These guidelines apply even if eating fish just during a vacation or for just one season.

Meal Size and Preparation

What is a meal of fish?

The recommendations are based on a portion size of 8 ounces (raw fish) for someone who weighs 150 pounds.

To adjust the meal size for a lighter or heavier weight - subtract or add 1 ounce of fish for every 20 pounds of body weight. For example, one meal would be:

  • 7 ounces for a 130-pound person, and
  • 9 ounces for a 170-pound person.

Clean and cook fish properly to deal with contaminants

Mercury cannot be removed through cooking or cleaning—it gets into the flesh of the fish. However, you can reduce the amount of other contaminants like PCBs by removing fat when you clean and cook fish.

remove skin, cut away the fat along the back, trim off the belly fat, and cut away the fatty area along the side of the fish

Questions & Answers About Fish Contaminants

Q. What are the contaminants found in fish and where do they come from?

A. In Minnesota, mercury is the contaminant in fish that causes the most concern. Air pollution is the major source of mercury that contaminates the fish in Minnesota's lakes and rivers. About 70 percent of the mercury in the air is the result of emissions from coal combustion, mining, incineration of mercury-containing products and other human sources. Over time, fish can accumulate relatively high mercury concentrations. That's why it's important to make wise choices about the fish you eat and how often you eat it.

There are also other contaminants in fish, including PCBs and PFCs. PCBs are man-made substances that were banned in 1976. Levels have declined, but PCBs are still found in the environment. Perfluorochemicals (PFCs) are a family of manmade chemicals that have been used for decades to make products that resist heat, oil, stains, grease and water.

Q. Which lakes and rivers have fish with contaminants?

A. All fish contain some mercury. It may seem surprising, but fish from lakes in the northeastern portion of Minnesota generally have higher levels of mercury. Although many of these lakes are relatively pristine, airborne contaminants still fall on them. Unfortunately, the sensitive natural water chemistry in these lakes efficiently turns non-harmful forms of mercury into a potentially harmful form. As a result, fish in these lakes accumulate more mercury.

PCBs are found mainly in Lake Superior and major rivers such as the Mississippi River. PFOS (Perfluorooctane sulfonate), a chemical in the PFC group, has been measured in fillets of several species of fish from the Mississippi river and metro lakes. The Minnesota Pollution Control Agency is leading an investigation into environmental contamination from perfluorochemicals.

Q. How can mercury, PCBs and PFOS in fish harm me?

A. In adults, prolonged exposure to mercury can damage your kidney and nervous system. It may cause tingling, prickling or numbness in hands and feet or changes in vision. Exposure to PCBs may increase the risk of cancer. Studies of laboratory animals exposed to low levels of PFOS show decreases in high-density lipoprotein (HDL or good cholesterol) and changes in thyroid hormone levels.

Q. How can they harm children and babies?

A. Young children, developing fetuses and breast-fed babies are at most risk, because small amounts of mercury can damage a brain that is just starting to form or grow. Too much mercury may affect a child's behavior and lead to learning problems later in life. Babies who are exposed to PCBs during pregnancy may have lower birth weight, reduced head size and delayed physical development. For more information:

Q. What can be done to reduce the amount of mercury in fish?

A. Mercury is found in many common household items, such as fever and cooking thermometers, thermostats and fluorescent lamps. One of the best ways to keep mercury out of the home and the environment is to avoid purchasing mercury-containing products and use mercury-free alternatives. When discarding products containing mercury, it is important to dispose of them properly. Using less energy and supporting alternative energy sources also reduces mercury in the environment.

For more information about preventing and reducing pollution, contact:

Minnesota Pollution Control Agency
(search for mercury, PCBs or PFOS)
651-296-6300 or 1-800-657-3864

For More Information

Updated Friday, May 12, 2017 at 03:38PM