Tuna- What you should know before you buy

Health Benefits of Canned Tuna

Tuna is a protein powerhouse, providing two thirds of the Daily Value (DV) in one 4-ounce serving. Power lifters and body builder’s have been known to eat large amounts of tuna to fuel muscle growth. It’s an excellent source of vitamin B3 (niacin), B6 (pyridoxine) and B1 (thiamin). Tuna is also a good source of the minerals phosphorus, potassium, and magnesium.

Tuna is an established food source of healthy Omega-3 fatty acids. Omega-3 fatty acids provide anti-inflammatory benefits. An increased level of omega-3s in the circulatory system is associated with better regulation of blood pressure and lower risk of ‘clogged’ blood vessels.

Tuna contains selenium found in a form called selenoneine. Selenoneine protects the tuna’s red blood cells from free radical damage and also combines together with mercury compounds to protect the fish from mercury poisoning.

Water or Oil?

Tuna packed in water can sometimes seem dry when compared to tuna packed in oil. However, the tuna packed in water may be the healthier choice. The oil used in canning tuna (Omega-6) mixes with the natural Omega-3 oils in the fish. When you drain the oil from the can, you lose the precious Omega-3 oils. As you know, oil and water do not mix, so the tuna packed in water retains the Omega-3 oils when drained.

White or Light?

Canned tuna is typically labeled as “white” or “light.” White tuna is always albacore. Light may refer to a number of species: bigeye, yellowfin, skipjack or tongol.

The highest levels of Omega-3 fatty acids are found in the white tuna or albacore. However, white tuna tends to be high in mercury as well- up to three times higher than mercury levels found in Skipjack tuna which is commonly sold as light tuna. A general rule of thumb is that the bigger and older the fish, the higher the mercury concentration.

Concerns about Mercury

Mercury pollution released into the environment becomes a serious threat when it ends up in our oceans and waterways, where it builds up in fish that we eat. Mercury works its way up the food chain as large fish consume smaller mercury contaminated fish. Instead of dissolving or breaking down, mercury accumulates at ever-increasing levels.

Humans risk ingesting dangerous levels of mercury when they eat contaminated fish, especially larger ocean species. Once in the human body, mercury acts as a neurotoxin, interfering with the brain and nervous system.

“This (high levels of mercury) is of particular concern for young children, whose nervous system, brain, heart, kidneys and lungs are all susceptible to the harmful effects of mercury.” – Environmental Defense Fund

The good news is that we can enjoy tuna as long as we do so responsibly and in moderation. Some guidelines from the NRDC (Natural Resources Defense Council):

  • Children under six, as well as women who are pregnant or planning to become pregnant, are the most vulnerable to mercury’s harmful effects.
  • A woman who is pregnant or is likely to get pregnant should eat no more than two cans of light tuna per week, or 2/3 of a can per week of white albacore tuna if she wants to stay below the EPA’s level of concern for mercury.
  • Since children get most of their mercury from canned tuna, it is important for parents to limit their children’s consumption to less than one ounce of canned light tuna for every 12 pounds of body weight per week

Cilantro and Tuna

It has been suggested that cilantro can be used to help rid the body of mercury and other heavy metal toxins. Here is an excellent recipe suggestion.


Tuna is the second most popular seafood in the United States. It can be enjoyed regularly without cause for concern. The key is moderation. The United States Environmental Protection Agency has released the following guidelines for safe consumption of tuna fish:


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