Headline:

"Fish oil supplements during pregnancy don't improve child's intelligence, study says"

There is a study where pregnant women consumed fish oil supplements, and the children were compared 4+ years later to the non-supplement children. The children scored the same. So the big headlines! Don't waste your money on fish oil supplements during pregnancy!

Now let's back up. What is DHA?

DHA (docosahexaenoic acid) is a fatty acid found in:

Fish (salmon, mackeral, herring, tuna, whitefish, sardine, sablefish, swordfish, striped bass, tilefish, trout, bluefish, sea bass, etc.)

Brains (lamb, beef, pork)

Testes (lamb)

mollusks (blue mussel, oysters, squid,)

crustaceans (blue crab, shrimp)

Our recommended average daily intake is about 0.5g. (4oz of atlantic salmon supplies about 3 times this amount.)

For amounts in each of these (and other) foods, please visit:

https://ndb.nal.usda.gov/ndb/nutrients/report?nutrient1=621&nutrient2=629&nutrient3=851&fg=&max=25&subset=0&offset=0&sort=c&totCount=5822&measureby=g

We hear a lot about the omega 3 content of seeds and nuts, and the idea that we can convert ALA to DHA and EPA.

Quote

Can adults adequately convert alpha-linolenic acid (18:3n-3) to eicosapentaenoic acid (20:5n-3) and docosahexaenoic acid (22:6n-3)?

The use of ALA labelled with radioisotopes suggested that with a background diet high in saturated fat conversion to long-chain metabolites is approximately 6% for EPA and 3.8% for DHA. With a diet rich in n-6 PUFA, conversion is reduced by 40 to 50%.

Ok, so we CAN make DHA from flax oil.. and to be sure to get enough, we should consume 1-2 Tablespoons of fresh flax oil a day. (Do your own research to see how much YOU want to take.. Flax oil can cause upset stomach, interact with medications, etc).

And get this.. they caution pregnant and breastfeeding women against consuming flax seed oil. Fish is limited because of mercury, and flax seed oil because its use has been related to preterm births (likely due to its blood thinning properties).

Quote

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4728620/

(DHA) is a structural constituent of membranes specifically in the central nervous system. Its accumulation in the fetal brain takes place mainly during the last trimester of pregnancy and continues at very high rates up to the end of the second year of life.

Ok, so now it looks like DHA is really important during the last 3 months of pregnancy, and for the first 2 years of life.

Since brain development continues after birth, what about breast milk?

I have searched all around for information, and there is are HUGE differences in the levels of DHA in breastmilk between people, based on their fish consumption. Japanese women have about seven times the DHA in their breastmilk compared to Americans. Guess who has the higher IQ scores? Average in the US is 100. Average in Japan is 105.

Quote

Animals fed an n-3 repletion diet at birth recovered to normal levels of both brain DHA and dopamine. However, a delay in feeding the n-3 repletion diet to the period following weaning resulted in only partial recovery of brain DHA and no recovery of the neurochemical factors. The implication is that early and prolonged insults from a severe n-3 deficiency may lead to irreversible damage to specific brain functions.

In other words, if a baby animal is born that is deficient in DHA, there is a window of opportunity to "catch up". But, if that time frame elapses with no remediation, the window closes, and the damage is permanent.

Ok, so after all that, I'll revisit that headline: "Fish oil supplements during pregnancy don't improve child's intelligence." The study evaluated the children 4 years after the mothers were supplemented. The period of rapid brain development after birth wasn't supplemented. AND the controls in the study received normal levels of DHA from their mothers.. they weren't fed deficient diets. So it is no surprise that there was little to no difference between the children.

The current recommendation is to consume 8-12 oz of fish a week.

9 hours ago, Berry78 said:

The current recommendation is to consume 8-12 oz of fish a week.

8oz-12oz ?

225 grams to 330 grams?

Geez, I eat that much fresh or canned fish every 36 to 48 hours. I must have a fair quota of good oils and DHA.

You are definitely getting plenty of those oils.. I might be concerned about mercury exposure. Here is a detailed article. It's a long, but worthwhile read for anyone that consumes fish.

http://www.whfoods.com/genpage.php?tname=george&dbid=103

@Berry78 We don't supplement. We definitely don't take flax oil (very high in phytoestrogens=nono for hormone pos bc). We don't eat any soy either. There is some new information about how much DHA/EPA we really need derived from how little DHA/EPA is actually metabolized from CLA. The belief may now be trending to being that we don't need as much as was previously thought--much like the Vitamin D and megadoses information that's now out there.

We do eat wild caught Pacific salmon, either fresh or canned about 1lb per week between the two of us--it makes 1 meal each, plus a spare meal each for breakfast or a light lunch. Then we will usually eat tilapia (responsibly farmed) or basa/pangasius for another meal--or I will have shrimp for that meal.

Oh and I do eat sardines in olive oil a couple of times a month.

But on the flip side, we eat very little PUFAs, so our balance of PUFA/Omega 3 isn't as bad as those who eat veggie oil and grains.

Edited November 1, 20178 yr by FluffyChix

I wanna, wanna, wanna hear the new info!(*jumping up and down*)

Everything I've come across says we need more than we usually get (but your example of 8oz per person for a week sounds spot-on for the current recommendations).

Google Ray Peat (he's an anti omega3 supp guy), who is hooked up to a lot of the newer studies on omegas. I don't think I agree with him whole-heartedly. I do believe we need some external Omega 3s, but what amount?

Here's an article by Chris Kresser (no time to really delve into it right now). https://chriskresser.com/should-you-really-be-taking-fish-oil/

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwjXxOb-uJ3XAhVFj1QKHW6nCEAQFggoMAA&url=http%3A%2F%2Fraypeat.com%2Farticles%2Farticles%2Ffishoil.shtml&usg=AOvVaw13JEEnQNYstqipSM1KjVb-

A very good article from Mary Enig (the late grate)--who was one of the foremost authorities on fat metabolism and wrote a great book called Know Your Fats. https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=3&cad=rja&uact=8&ved=0ahUKEwjXxOb-uJ3XAhVFj1QKHW6nCEAQFgg-MAI&url=https%3A%2F%2Fwww.westonaprice.org%2Fhealth-topics%2Fknow-your-fats%2Fa-reply-to-ray-peat-on-essential-fatty-acid-deficiency%2F&usg=AOvVaw1BmcTODR0-Fd9ezmY0Z_gS

Very cool. Ok, so I guess we should make the distinction between fish oil supplements and eating fish.

Supplements.. it's hard to know if the oils are fresh. But for people (especially kids) that refuse to eat fish, supplements are probably better than none. A lot of the studies with less than favorable results had people taking 3-5g of oil a day. The supplements in my fridge are 2g for the recommended daily consumption.. so it's possible those studies were proving that there is a maximum.

I'm always trying to minimize pills where possible, so of course fish is better.

I did come across a study that showed canned and fried tuna retained virtually zero DHA. Boiling for 10 minutes retained almost all of it. (I had a sneaking suspicion that how fish is cooked makes a difference).

Other types of fish don't seem as sensitive.

So much for all of us eating canned tuna as a health food!

9 hours ago, Berry78 said:

8oz per person for a week sounds spot-on

Really?

8oz [225g] ? That is one to two fish meals per week.

That 225g should be a minimum for meat eaters ... more fish would be better for a lot of people.

On 11/1/2017 at 1:41 AM, Rainbow_Warrior said:

8oz-12oz ?

225 grams to 330 grams?

Geez, I eat that much fresh or canned fish every 36 to 48 hours. I must have a fair quota of good oils and DHA.

Ok, so with your high level of consumption, I looked at the mercury level chart as it would pertain to you. I don't know where your fish come from (which is really important), but if they come from the Atlantic and/or Pacific then the following are the only types you should ever eat:

Pacific anchovies

Atlantic herring

Pacific mussels

Atlantic pollock

Pacific canned or fresh salmon

Scallops

Shrimp

There may be safe fish that aren't on my list, they would have to be looked up individually. They should have .04mg/kg mercury or less.

If you eat local fish or types other than what are on this list, I highly recommend you get tested for your mercury level. Ask your doc.

For those that eat 12oz a week or less, they can eat all the fish in Rainbow's list, and can add:

Cod

Flounder

Herring

Pacific Mackerel

Atlantic mussels

Oysters

Ocean Perch

Pacific pollock

Atlantic salmon

Pacific yellowfin tuna

For regular fish eaters (12oz/week), we should NEVER eat fish that have a level higher than 0.13mg/kg mercury.

8oz/week open up a few more (.20mg/kg):

Pacific crab

Pacific lobster

Pacific albacore tuna

You hear "limit consumption" so you think if you eat shark once a month it's fine. Right? Actually, it's only fine if that were your only fish consumption at all. If you also eat salmon or shrimp or anything else, you've gone over the safe level.

Ok, here is another way of looking at it for yourselves.

First, figure out your personal mercury maximum based on your ideal weight.

100lbs = 5mcg/day, 35mcg/week

125lbs = 6mcg

150lbs = 7mcg

175lbs = 8mcg

200lbs = 9mcg

Ok, now, you'll use the ppm (or mg/kg.. they are equivalent) in the chart.

Figure up how many grams of fish you want to consume per day or week (28.4g =1oz)

Multiply ppm * [grams of fish] = mcg of mercury consumed.

Here is the fish chart:

https://www.fda.gov/food/foodborneillnesscontaminants/metals/ucm115644.htm

Here is an example:

So, my ideal weight is 150lbs. I don't want to consume over 49mcg of mercury a week.

I want to eat fish 3 times a week, 4oz each time. That is 12oz (341g).

I want to eat canned chunk light tuna, which has an average of 0.126ppm.

0.126(341) = 43mcg

43 is less than 49, but not by much. Keep in mind, we get mercury from other places, not just fish, so we don't want to get too close to our maximums.

And, if the reason I want to eat fish is DHA, and there isn't any in the canned tuna, then maybe I want to switch to frozen skipjack. It has only a little more mercury (0.15ppm)... but that small difference puts me over my 49mcg limit. (It gives 51mcg).

Crazy stuff....