It’s Seafood Month-Here are some reasons to eat a fish

Every month is seafood month at my house. October, however, is the official U.S. Seafood Month so now’s a good time to cast a glance over some of the ways we benefit from seafood. 

For all you old people or those who want to be old someday—In October 2018 Zhang and colleagues published one of the largest and most in-depth studies of how seafood affects our health.  Their work followed 240,729 men and 180,580 women for 16 years.  In their study, they grouped people into 5 groups based on highest to lowest levels of seafood consumption. They followed the group for 16 years to see what effect eating seafood had on deaths due to many different diseases.

The highest 20% of seafood eaters among men ate about 7.4 ounces per week; for women it as 6.3 ounces. Those in the lowest consuming 20% group were 0.9 ounces and 0.7 ounces, respectively.  The study population came from six states plus two metro areas and all were between 50 and 71 years old at the study’s beginning.

In comparing the highest vs lowest seafood consuming groups the authors found these changes in death rates. 

Comparison of death rates between highest and lowest seafood consumption groups for: WomenMen
All causes-8%-9%
Alzheimer’s disease-38%-24%
Respiratory diseases-19%-20%
Liver disease-15%-37%

In these outcomes, the one for Alzheimer’s stands out.  As our population ages, the number of those with Alzheimer’s will increase and its effects are insidious.  Not only does it upend the life of the person afflicted, it also reaches into a much larger network of family and friends.  It’s hopeful to me that by changing our diets we can help thwart Alzheimer’s.

I cherry-picked a bit for the results in the table.  Zhang reviewed many more diseases and you can see all their results in Tables 2 and 3 in their article.  

The importance for seafood for adult health and wellness may even be eclipsed by its importance for kids.  The extent of this is stunning and heartening.  And, with that let’s swing to the other end of the age spectrum-pregnant moms and young kids. 

Seafood’s importance for kids shines in its benefits on neurocognitive development. There are many measures of kids’ neurological development. Developmental psychologists measure verbal skill, manual dexterity, the ability to distinguish distinct sounds and IQ as well as many others. Eating seafood affects all of these. 

To focus down a bit onto IQ scores, children of mothers who eat seafood during pregnancy have higher IQ scores. The effect is a big one. 

European Food Safety Authority (EFSA) metastudy compared kids whose moms at three versus no servings of seafood weekly.  EFSA found the kids from seafood eating moms had an IQ score 8 points higher (see here page 24). Another group at the Southampton General Hospital in the UK found a 7.5 IQ score increase for kids of moms who ate fish during late pregnancy.  

Beyond that, the Southampton group found that kids from moms who ate oily fish (such as salmon, mackerel and sardines) early in pregnancy had a lower incidence of hyperactivity disorder when compared to kids from moms who didn’t eat oily fish.

Fish, especially oily fish from cold waters, are a good source of omega-3 fatty acids. And, abundant evidence shows that omega-3s are crucially important to many aspects of our health.   But the developmental benefits kids receive come from eating seafood as a whole food.  Many scientists have looked at the effects of supplementing pregnant women’s diets with omega-3s but they find no effect from either fish oil or the individual omega-3s (EFSA page 31; another study is here, it is an 800 page slog but they list summary findings on the first couple pages; lastly, see here for the latest compilation). 

The benefit story, then, is not one about the effects of ingredients. The takeaway message is that fish is much more than the sum of omega-3 or protein or vitamins it contains. It is as a whole food that fish is a stellar path to the apex of healthful nutrition. Plus. It tastes really good which is another superb reason to make any month a seafood month.