A guide to fish: Lean vs fatty

Posted by Dayne Hudson in Weight Loss

Estimated reading time: 5mins

Fat content in different types of fish

Per 100 grams, the fish with the highest fat content are:

  • Mackerel = 16 grams of fat
  • Herring 13.2 grams of fat
  • Salmon = 11 grams of fat
  • Sardines = 9 grams of fat
  • Trout, rainbow, farmed = 5 grams of fat 
  • Anchovy = 4.7 grams of fat

Fish is classified as a lean source of protein, and for good reason.

Mackerel, with 16 grams of fat, isn't too large considering the protein you get with it.

But it's critical we know the fat content regardless, as some women on a weight loss diet will have a daily limit of 50-60 grams of fat per day.

So in this context, 16 grams would be a significant percentage.

A popular fish variety, salmon, has 11 grams of fat.

Again, this isn't anything too large, but people tend to forget about it when consuming foods like sushi, having up to 200-300 grams of salmon and thinking it's "lean" and that they've consumed "next to no fat."

But in reality, this is up to 30 grams, not at all insignificant!

For a quick snapshot, here is what 100 grams of smoked salmon looks like.

A popular fish variety, salmon, has 11 grams of fat per 100 grams.
A popular fish variety, salmon, has 11 grams of fat per 100 grams.

Leanest types of fish

The leaner types of fish, the ones you can eat a large amount of without worrying about fat content, are:

  • Haddock = 0.6 grams of fat
  • Whiting = 0.7 grams of fat
  • Cod = 0.7 grams of fat
  • Boiled prawns = 0.9 grams of fat
  • Oyster = 1.3 grams of fat
  • Steamed scallop = 1.4 grams of fat
  • John Dory = 1.4 grams of fat
  • Squid = 1.5 grams of fat
  • Tilapia = 1.5 grams of fat
  • Boiled lobster = 1.6 grams of fat
  • Barramundi = 1.8 grams of fat
  • Clam, cooked = 2.4 grams of fat
  • Boiled mussel = 2.7 grams of fat
  • Bream = 2.9 grams of fat
  • Red mullet = 3.8 grams of fat
  • Tuna = 4.6 grams of fat
  • Boiled crab = 5.5 grams of fat
Cod is one of the leanest fish you can eat, with just 0.7 grams of fat per 100 grams.
Cod is one of the leanest fish you can eat, with just 0.7 grams of fat per 100 grams.

Seafood for fat loss

You can see how these varieties of fish are very lean. They're also high in protein, meaning at any time, these fish are a great protein source during a weight loss diet!

Fish can also be cooked many different ways with different seasonings and low-calorie sauces, adding much-needed flavour and variety when weight loss is the goal.

Health benefits of fish and seafood

Whilst utilising the low-calorie benefits of fish and seafood, there is also a plethora of health benefits.

Fish contains fatty acids, selenium, iodine, vitamin D, and taurine, which may help us reduce our likelihood of developing cardiovascular disease.

A review in 2019 which included data from over 10 studies, found fish oil to lower the risk of a heart attack and death from coronary heart disease.

Consuming fish fights heart disease in these different ways:

  • The omega-3 fatty acids in fish protect the heart against the development of erratic and potentially deadly cardiac rhythm disturbances.
  • They lower blood pressure and heart rate, improve blood vessel function
  • At higher doses, omega 3s can lower triglycerides and might ease inflammation.

Further research finds seafood helps with brain and eye health, and it's recommended we consume two servings per week.

Moreover, other research finds fish to be beneficial for the immune system, whilst playing a role in favourable gut health.

Moreover, women who are pregnant can benefit further from fish intake, as it's been found to be important for optimal development of a baby’s brain and nervous system:

"...in general, how much fish women ate during pregnancy appeared to have little long-term relation with neurodevelopmental outcomes in their child."

Regular fish intake might also help us reduce the risk of depression, stroke, and Alzheimer's disease.

Pregnant women consuming fish might be doing their babies brains wonders
Pregnant women consuming fish might be doing their babies brains wonders

And if you can't stomach fish at all, then you can consider getting your omega 3s from elsewhere; flax seeds, walnuts, and some vegetable oils.

The other alternative is an omega 3 fish oil supplement.

In summary of lean vs fatty fish

The leanest fish we can eat are options like barramundi, whiting and cod, and the fattiest are mackerel, herring and sardines. All fish is great on a fat loss diet, but just ensure you're keeping track of the fat content per 100 grams of consumption for simplicity. Fish is beneficial for our health; containing fatty acids, selenium, iodine, vitamin D, and taurine, which may help us reduce our likelihood of developing cardiovascular disease. It can also assist with brain, eye and gut health, whilst maybe reducing the likelihood of depression, stroke, and Alzheimer's disease. Fish intake is also important for pregnant women for the development of babies brains and nervous systems. It's recommended we have two servings of fish/seafood per week.


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