All fish contain some level of mercury, but the amount varies significantly by species. Generally, larger, longer-lived predatory fish tend to accumulate higher levels of mercury in their tissues. Therefore, when these types of fish are processed and canned, they will carry their inherent mercury content.
High-Mercury Canned Fish Varieties
Some canned fish varieties are known to have higher mercury levels due to the type of fish used. These varieties should be consumed with caution, especially by vulnerable populations.- Tuna:
- Bigeye Tuna: While sometimes used for sushi, if bigeye tuna were to be canned, it would be among the highest in mercury.
- Albacore Tuna (White Tuna): Often found canned, albacore tuna typically has a higher mercury content than light canned tuna because albacore are larger, older fish.
- Mackerel (King Mackerel): While smaller mackerel species like Atlantic mackerel are lower in mercury, King Mackerel is specifically identified as very high in mercury. If canned King Mackerel were available, it would pose a significant mercury concern.
- Other fish known for very high mercury levels like orange roughy, shark, and swordfish are less commonly found in canned form, but if they were, their canned versions would also be high in mercury.
It is important to note that fish with very high mercury levels should be consumed only very occasionally, if at all. This is particularly crucial for children and people who are or could become pregnant, who should avoid them entirely.
Lower-Mercury Canned Fish Options
For those looking to include canned fish in their diet with less mercury concern, several excellent options are available:- Skipjack Tuna (Light Tuna): This is the most commonly canned tuna and typically has lower mercury levels than albacore tuna. It's often labeled as "chunk light" tuna.
- Salmon: Canned salmon (pink, sockeye, etc.) is generally very low in mercury and is an excellent source of Omega-3 fatty acids.
- Sardines: These small fish are low on the food chain and are very low in mercury, making them a safe and nutritious choice.
- Anchovies: Similar to sardines, anchovies are small and have very low mercury levels.
Making Safer Choices
Being mindful of your canned fish choices can help reduce your mercury exposure.For comprehensive guidance on fish consumption and mercury levels, you can refer to resources from reputable health organizations like the U.S. Food and Drug Administration (FDA).
Consider the following table for a quick overview of common canned fish and their general mercury content:
| Canned Fish Type | General Mercury Level | Notes |
|---|---|---|
| Albacore Tuna | Moderate to High | Larger fish; "white tuna" |
| Skipjack Tuna | Low to Moderate | Smaller fish; "chunk light tuna" |
| Canned Salmon | Very Low | Excellent source of Omega-3s |
| Sardines | Very Low | Small, bony fish, good source of calcium |
| Anchovies | Very Low | Small fish, often used for flavor |
| King Mackerel | Very High | Less common in cans, but high if found |
By understanding which types of canned fish are higher in mercury and opting for lower-mercury alternatives, you can enjoy the nutritional benefits of fish with greater peace of mind.
