Tuna is abundant in protein but low in fat, which makes it one of healthiest foods on the planet as well as one of your best allies during the weight loss process.

However, the question regarding its safety has been raised due to the amount of mercury it contains and its effect on the people who consume it. This doesn’t mean that you shouldn’t eat tuna, but that you should eat only a certain type in order to avoid the risk of mercury poisoning.

Is Tuna Toxic?

Even though the amount of mercury in tuna is something you need to pay attention to, this information is partially right. Namely, most mercury that enters the ocean is not actually harmful and the conversion of mercury into methylmercury makes tuna potentially dangerous.

The above-mentioned methylmercury is highly toxic and it is converted from mercury by some species of bacteria living on the ocean floor. It tends to build up in large predatory fish like tuna because they eat prey containing it.

According to a study which collected over 100 different tuna samples from 54 sushi restaurants and 15 grocery stores, the mercury levels were highest in bluefin and bigeye tuna, which are actually two of the biggest tuna species. On the other hand, the lowest levels were found in one of the smallest species: skipjack tuna. Therefore, the bigger the tuna is, the more mercury it contains.

How to Choose Canned Tuna?

Even though the general rule says that the smaller a tuna is, the less mercury it contains, the way it is harvested is very critical element when it comes to the mercury levels. Labels on tuna can make it difficult to determine what you should eat to avoid mercury, so here is a list of the most and least toxic forms of canned tuna.

1.      Chunk Light

Chunk light is actually a blend of various tuna species, such as low-mercury species like skipjack and high-mercury species like bigeye. Therefore, it is recommended to avoid this type of canned tuna.

2.      Chunk White

Chunk white is generally safe to consume because it is made of albacore tuna.  This is one of the healthiest fish and even though it is not the smallest species of tuna, they are caught when they are young, meaning that the fish didn’t have enough time to accumulate mercury.

3.      Canned Light

Canned light is basically made from skipjack tuna, one of the smallest species of tuna. This means that it has lower levels of mercury and it is one of your best options. However, some studies have found that the mercury levels in canned light can be dangerous for children and woman.

Who Should Eat Tuna

Most people can consume tuna without any adverse effects. However, some people are at higher risk for mercury poisoning than others.

According to information based on findings from the U.S. Environmental Protection Agency, a child weighing approximately 48 pounds that eat more than 1.4 ounces of tuna weekly can be at risk of brain damage as a result of mercury exposure. The same goes for women weighing around 140 pounds who should limit their tuna intake to no more than 4.5 ounces weekly.

Symptoms of Mercury Poisoning

-          Loss of hair, teeth and nails
-          Blindness
-          Loss of hearing
-          Impaired memory
-          Lack of coordination
-          Abnormal speech patterns
-          Red cheeks, fingers, and toes
-          Bleeding from the mouth and ears
-          Rapid heartbeat
-          High blood pressure
-          Intense sweating

In case you are experiencing any of the above-listed symptoms and are consuming mercury-laden foods, it is very likely that you are suffering from mild mercury poisoning.

Source: http://theheartysoul.com/is-tuna-toxic/