When it comes to introducing new foods to your baby, it can seem like there are a lot of things to keep in mind! How should you introduce solid foods to your baby's diet, should you give a food or not, do you need to be concerned with potential allergens, how do you introduce a variety of foods? And fish for babies is right at the top of those concerns. So let's talk about it!
Fish Is One of the Top Allergenic Foods
First and foremost, there is good reason to be sure to include fish in your baby's diet. Fish is one of the top 9 foods that can cause a food allergy. If we consider seafood as well, then we are talking about two of the top 9 foods.
Recent research has shown the importance of introducing potential food allergens early, ideally around 6 months of age and before 1 year. This goes for babies with a family history of food allergies, or other high risk concerns like severe eczema, as well.
We know that introducing foods that have a high risk for an allergic reaction for the first time early, and then continuing to expose them to that allergen for several years can actually be protective against food allergies. Which means we have the potential to lower the number of people with a fish allergy simply by introducing it intentionally to our babies.
Other Health Benefits of Fish
On top of the potential to prevent the development of an allergy, there are several other reasons that fish is an important food for your baby.
Fish is a great source of protein. But more importantly than that it is a fairly good source of heme iron. Iron is one of the essential nutrients that your baby needs to get from foods in their first year of life.
There are several different types of fish that are also great sources of omega-3 fatty acids. Omega-3 fats are types of essential fatty acids, like the highly beneficial docosahexaenoic acid (DHA), that have many functions in the body. They help with brain development, as well as potentially function in cell development and immune system functioning.
Levels of omega- 3 vary by the type of fish, but a general rule of thumb is that fatty fish (like salmon) are the best choices for helping get the omega-3 benefits for your baby's brain development and overall health.

Vitamin D in Fish
Vitamin D is another nutrient of concern for babies, and one that is actually fairly hard to come by in food. Some variety of fish (like salmon and sardines), especially ones with bones in them, can actually be a good source of vitamin D. And yes, the bones are soft enough that babies can eat them!
Is Fish Safe for Babies?
Now that you know the health benefits of including fish in your child's diet, let's talk about the other side of things.
Many fish can have high levels of mercury in them. Mercury is an element that is incredibly toxic to people. It can have an effect on everything from the nervous system to the digestive and immune systems as well as many other organs. (Ref)
Even more concerning, high mercury levels can be incredibly damaging for pregnant women and young children due to the effect mercury has on brain development in an unborn baby and in younger children. (Ref)
So what does that mean for your baby?
Incorporating Fish In Your Child's Diet
Like with most things nutrition related, fish is not all good or all bad. Too much of anything can be harmful for us, and fish is no exception. So how do we know how much fish is safe for our kids, and which ones to choose?

The American Academy of Pediatrics recommends 1-2 portions of fish weekly for babies and children. They recommend focusing on fish from the best and good choices categories. These categories, developed by the Food and Drug Administration and the Environmental Protection Agency, would mean that it is safe for babies to have fish with mercury at or less than .23 microgram/gram. But let's get technical for a minute because I think it's really important here.
Let's Look at The Actual Mercury Levels in Fish
When it comes to feeding babies, I prefer to be on the safer side. We know that mercury is incredibly neurotoxic to babies. The World Health Organization actually recommends keeping mercury intake to 1.6 micrograms/kg of bodyweight per week. If we're strictly looking at an average baby weight, let's say that 6-12 month olds weigh between 7-9 kg (about 16-20 pounds.)
Using that, the most mercury that a baby should have is somewhere between 11.2 micrograms and 14.4 micrograms. If we use the 2 servings a week guideline, that means 2 ounces (or 56 grams) of fish. With that number, it is safe for 16 pound babies to have fish with up to .2 micrograms of mercury per gram. For bigger 20 pound babies, that number would go up to .26 micrograms per gram.
Baby Fish Serving Size Recommendations
But the key here is 2 ounces! That's not much fish when it comes down to it. These guidelines for babies and toddlers were put into place when babies generally ate baby food only. Now that baby led weaning and finger foods are much more popular, it is entirely plausible that your baby would easily eat more than 2 ounces of fish at just one sitting.

On top of that, if you know anything about my feeding philosophy, I put great importance on allowing your child to choose how much food to eat of what you serve. It can impact your feeding relationship with your child if you start to limit the amount of food that they eat once you've served it. That's just something that we want to avoid.
So what's the solution?
The Best Types of Fish for Babies
There is no one size fits all solution. The best way to look at this is to evaluate the amount of fish that you want to incorporate into your diet.
If you're someone like me who doesn't really enjoy fish and will have a hard time incorporating it into your family's diet, then you can safely stick with the guideline to feed fish under .23 micrograms of mercury/gram. With that, your baby getting up to 2 ounces a week of it would be safe. Although it is likely best to serve it all at once to allow them to choose how much they eat of it instead of breaking it up into multiple meals.
If you incorporate fish frequently in your family's diet, then it is going to be even more important to limit fish with higher levels of mercury. With this, if you kept the levels of mercury in the fish to .06 micrograms/gram or less, your baby could safely have up to 8 ounces or 224 grams of fish a week.
What about if you want to serve fish that falls above .06 micrograms but below .23 micrograms and your baby is likely to eat more than 2 ounces? Spread out how often you serve it. If your baby is likely to eat 4-8 ounces of the fish, try serving it every other week or once a month. Spreading out the medium mercury fish is another way to approach it.
So what fish types fall under those levels?
The Best Low-Mercury Fish for Babies (at or under .06 micrograms/gram of mercury)
Let's start with the fish with the least amount of mercury. Good choices tend to be small fish, as they have not had the lifespan or diet that increases mercury levels.
All the fish with asterisks (*) are ones that are also good sources of omega-3 fatty acids. (Ref) Which means prioritizing them for our children is a great idea!
In order of average concentration levels of mercury according to the US EPA:
- Scallop
- Tilapia
- Shrimp
- Sardines*
- Canned salmon*
- Oyster*
- Clam
- Squid
- Fresh or frozen salmon*
- Catfish
- Anchovy*
- Pollock*
- Crawfish
- Shad*
- Whiting
- Mullet
- Atlantic mackerel*
- Haddock
- Flatfish
- Crab
- Butterfish
Good Choices for Babies (at or under .23 micrograms/gram of mercury)
- Freshwater trout*
- Striped bass (ocean)*
- Atlantic croaker
- Smelt
- Herring*
- Hake
- Whitefish*
- Sheepshead
- Pickerel
- Pacific chub mackerel*
- Lobster
- Cod
- Carp
- Perch (ocean)
- Canned light tuna (includes skipjack)
- Black sea bass*
- Tilefish (from Atlantic Ocean)*
- Skate
- Buffalofish
- Perch, freshwater
- Monkfish
- Snapper
- Mahi mahi
- Weakfish/sea trout
- Rockfish
- Halibut* (this one averages .24 ug/g so is slightly out of the limits but still acceptable occasionally.)
Fish to Avoid for Babies (.25 micrograms/gram of mercury or higher)
There are several fish that are recommended to be avoided by pregnant women and babies due to their higher levels of mercury. The larger fish tend to be the worst fish when it comes to mercury levels. Large fish generally eat smaller fish, which means that they are ingesting the mercury the small fish have and it is being concentrated in them. (Ref)
- White croaker/Pacific croaker
- Yellowfin tune
- Canned tuna, albacore or white
- Spanish mackerel
- Chilean sea bass/Patagonian toothfish
- Albacore tuna/white tuna fresh/frozen
- Sablefish
- Bluefish
- Grouper
- Marlin
- Orange roughy
- Bigeye tuna
- King mackerel
- Shark
- Swordfish
- Tilefish (from the Gulf of Mexico)
Farmed Fish Versus Wild Fish and Other Considerations
The above list focuses strictly on mercury and omega-3 levels. When it comes to fish, we know that there are other things to consider from a sustainability standpoint as well.
No method, whether fishing or farming, is foolproof. Each method has it's pros and cons, as well as companies and people who are doing it well and those that aren't. It is hard to say something like all atlantic salmon are farmed and should be avoided, which I have heard before. But there are definitely things to consider when it comes to farmed fish, for our own health as well as the environment.

The best way I have found to evaluate these issues is to use the Monterey Bay Aquarium's Seafood Watch Program. There you can search the best choices for the type of fish you would like to buy.
It will tell you if a type of fish is certified, is from a responsible company, and so much more. It is a great resource to go a step beyond mercury issues.
How to Evaluate Fish Not on This List
This list was created from the list maintained by the United States Environmental Protection Agency. Which means that if you are in a different country, there is a chance that fish you have access to is not on this list.
Most regions have local agencies that maintain mercury advisories. The best thing to do is find the list relevant to your local area and the fish available to you. Then use the numbers of .06 micrograms/gram and .23 micrograms/gram to find the fish that fall within these limits.
Nutrition and Feeding Our Babies Is a Balancing Act
Wouldn't it be easier if everything about nutrition and feeding was black and white? Unfortunately, that's just not the case. Things like fish can be both incredibly beneficial and potentially harmful to our kids.
It is a balancing act that will be playing out with our kids for years to come.
And it's why putting the focus on incorporating a variety of different foods into your child's diet is often the best, and most protective, approach. Then you will get the benefits of lots of different foods, without needing to be overly concerned with the potential downfalls of them as well.
Hello! Thank you so very much for this post. Browsing the Seafood Watch web-site, which you linked here, made me realize just how difficult it is to find good quality fish. Are there any brands of fish that you have used and can recommend?
It really is difficult! Unfortunately, there are just so many different brands available in different stores that it can be hard to give a general recommendation. The seafood watch website is going to be your best bet, even just in store when you’re buying. It is a bit easier for canned fish though- Safe Catch and Wild Planet are two companies that have some good options I’ve found!