Does Subway Tuna Contain Mercury?

Subway’s tuna sandwiches are a popular menu item, appreciated for their affordability and convenience. But some have raised concerns about potential mercury exposure from frequently eating Subway’s tuna. So does Subway tuna actually contain mercury, and is it safe to eat?

Like all tuna, Subway’s contains small traces of mercury. However, mercury levels are low enough that tuna can be safely consumed in moderation as part of a balanced diet. By limiting intake and varying seafood choices, mercury exposure from Subway tuna is unlikely to pose health risks.

Why Tuna Contains Mercury

All tuna contains some mercury which gets into oceans and rivers through industrial pollution. It accumulates in large fish like tuna through a process called bioaccumulation.

When humans eat contaminated fish, mercury is absorbed into the bloodstream and can build up in body tissues. High mercury concentrations can be toxic and lead to a condition known as mercury poisoning.

Symptoms include impaired brain function, numbness, muscle weakness, vision problems, and irritability Fetuses are especially vulnerable, as mercury can harm development.

To lower mercury exposure, health officials tell people, especially pregnant women and kids, how much seafood they should eat.

Mercury Levels in Canned Tuna

Subway uses canned tuna in its sandwiches. Canning processes do not remove mercury.

Levels of mercury in canned tuna average around 0. 1-0. 3 parts per million (ppm), with albacore tuna on the higher end. Guidelines consider under 0. 5 ppm to be a low mercury fish.

For comparison, swordfish averages 0.995 ppm, tilefish 1.450 ppm, and shark 1.101 ppm. So tuna is on the lower end for mercury concentrations.

Subway uses skipjack tuna in its sandwiches, which tends to be lower in mercury than albacore. Still, some mercury is present.

Is The Mercury in Subway Tuna Dangerous?

In moderation, the small amounts of mercury in Subway tuna are unlikely to cause health issues.

According to the FDA, eating up to 12 ounces (two average meals) of low-mercury fish like canned light tuna per week is considered safe.

Consuming Subway tuna subs within these limits, as part of an overall balanced diet, carries little risk. Eating tuna daily or in excessive quantities is when potential issues could arise.

Sensitive groups like pregnant women and young children do need to be more cautious. But for most people, infrequent tuna intake poses minimal risk.

How Much Tuna Can You Safely Eat?

Authoritative food agencies provide the following weekly intake guidelines regarding low-mercury tuna like Subway uses:

• FDA: Up to 12 oz per week

• EPA: Up to 11 oz per week

• WHO: Up to 3.5 oz per week

Observing these recommendations allows you to incorporate tuna as part of a varied, nutritious diet while limiting mercury exposure. The less often it is consumed, the lower the risk.

Tips For Reducing Mercury From Tuna

Here are some tips to further minimize mercury exposure from occasional Subway tuna subs:

• Alternate tuna with low-mercury fish like salmon, tilapia, shrimp

• Choose smaller tuna like skipjack over albacore

• Consume tuna in moderation following guidelines

• Avoid additional seafood meals when eating tuna

• Increase intake of selenium-rich foods like nuts and seeds that can bind mercury

By varying your protein sources and diet overall, you can safely incorporate some Subway tuna sandwiches without significant mercury concerns.

Who Needs To Be Most Cautious?

Pregnant women, nursing mothers, and young children should take extra care to limit tuna mercury exposure as fetuses and developmental stages are most sensitive.

The FDA and EPA recommend pregnant/nursing women eat no more than 6 oz (1 average meal) of low-mercury tuna like light canned per week. Albacore tuna should be avoided.

For small children, amounts should be smaller and intake infrequent. Children’s developing brains and nervous systems are vulnerable to mercury’s effects.

Those who already consume a lot of fish or have other mercury exposure sources may also want to moderate intake.

How Subway Can Reduce Tuna Mercury Levels

Subway does not currently detail any efforts to reduce mercury in its tuna supply chain. But some practices could potentially lower levels:

• Sourcing tuna from less contaminated regions and fisheries

• Avoiding larger, older tuna which accumulate more mercury over time

• Implementing third-party mercury testing programs on tuna

• Supporting industry innovations to reduce mercury absorption in fish

For now, Subway tuna likely contains average mercury levels compared to other canned tuna. But efforts could be made to minimize concentrations.

The Bottom Line

Overall, consuming Subway tuna subs occasionally and in moderation poses negligible mercury health risks for most people without underlying health conditions.

By following authoritative guidelines for low-mercury fish intake and incorporating a variety of seafood in your diet, the small amount of mercury in Subway tuna is unlikely to cause harm.

However, daily or excessive consumption over time could potentially lead to a buildup of mercury in the body and associated health effects. Moderation and variety is key.

While Subway tuna does contain some traces of mercury like all tuna, intake within recommended limits as part of an overall balanced diet is considered safe by health experts.