By Dr. Alyssa Musgrove
Seafood can be a great addition to a healthy diet, providing a great source of protein, and the heart, and brain-
healthy omega-3 fatty acids. But seafood can also carry a long list of chemicals that can render it unhealthy.
Due to widespread pollution, most types of seafood have some degree of contamination which is generally unavoidable. However, some types of seafood have such high levels of contaminants they qualify for seizure by the FDA.
Most consumer seafood guides rate fish based on sustainability (health of the population, environmental impact of fishing method, etc), but fail to consider the toxicity levels of those fish. Below are some guidelines to help you avoid the seafood with the highest level of contaminants and direct you toward healthier options.
Seafood to Avoid or Reduce Consumption of:
Tilefish, Swordfish, Shark, King Mackerel
These fish are the apex predators of the ocean and have some of the highest levels of the neurotoxic chemical methylmercury. Methylmercury exposure can result in a long list of serious health issues including autoimmune disorders, insomnia, memory loss, immune system damage, cognitive dysfunction, tingling in the extremities, seizures, depression, anxiety and delayed development. It’s best not to consume these fish.
Tuna
Tuna consumption is our primary exposure to the neurotoxic chemical methylmercury. Tuna are higher up on the ocean food chain and bioaccumulate toxins easily.
Atlantic Bluefin and Bigeye tuna, most commonly served as sushi tuna, have the highest levels of methylmercury of all tuna species and should be avoided, especially by women of childbearing age, and women who are pregnant or nursing.
Yellowfin & Albacore tuna are referred to as “chunk lite” and “white meat” respectively and are often found in canned tuna (although Yellowfin is also served as sushi). Both species of tuna have moderate levels of methylmercury. Limit consumption of this type of fish to 1-3 times per year, or never if you have known heavy metal issues.
Skipjack tuna is the smallest of the tuna species and therefore has the lowest amount of methylmercury contamination (although still much more than salmon). If you are going to eat any canned tuna, be sure it’s Skipjack, or that you’re buying the SafeCatch brand, which tests every fish for methylmercury levels. Children under 55 pounds should limit Skipjack tuna consumption to once per month.
Farmed Salmon
Most of the salmon in restaurants and grocery stores is farmed Atlantic salmon. Farmed salmon, no matter where it’s from, can have very high levels of polychlorinated biphenyls, or PBC. These chemicals were banned decades ago due to their health effects, but because they are persistent in the environment are still found in animal foods. Similarly, farmed salmon can have high levels of dioxins, a potent carcinogen and hormone
disrupting chemical. Even imported salmon from places like Scotland and Norway are farmed, so pass on these as well.
Imported Shrimp
Most shrimp is imported from Southeast Asia, where regulations about fish farming are lax. Shrimp is notorious for being raised in filthy water, and is regularly dosed with antibiotics, pesticides, hormones, and other chemicals banned in other countries. Since the FDA inspects less than 2 percent of imported seafood, most of these contaminated shrimp pass freely into commerce. Shrimp farmed or caught domestically in the US are a healthier option. (There’s a vendor who catches shrimp off the Georgia coast every Thursday and sells them
fresh (not frozen) on Saturday at the Harmony Farmer’s Market.)
Tilapia
Tilapia is a popular mild tasting whitefish. Nearly all tilapia is farmed and can contain several contaminants like pesticides and antibiotics. Additionally, because of the feed given to farm raised tilapia (like corn and soy), they have a higher ratio of inflammatory omega-6 fatty acids to anti-inflammatory omega-3 fatty acids. This renders the fish nutritionally inferior, and with the pesticides and antibiotics, not a good choice for consumption.
So, what seafood should you eat? SMASH is a handy acronym to help you choose fish with the highest nutritional value and lowest levels of contamination. SMASH fish are all shorter lived, lower on the food chain species that can make great alternatives to the more contaminated types of seafood. SMASH fish include:
Salmon (wild caught from the Pacific only)
Mackerel
Anchovies
Sardines*
Herring
*Some types of sardines can have higher levels of PCBs and should be consumed in moderation.
By keeping the SMASH acronym in mind the next time you’re at the grocery store, you can reap the nutritional benefits of seafood, while limiting toxicity and chemical exposure.
Pathways to Healing specializes in holistic chiropractic care. Dr. Alyssa Musgrove draws on a variety of techniques, including chiropractic, kinesiology, nutrition, food allergy testing and lifestyle counseling to assist clients in achieving optimal health and wellness in one setting. Pathways to Healing is located at 1022 Founders Row, Lake Oconee Village, Greensboro. The office can be reached at 706-454-2040.