http://gillseafood.com

Peter Willatts, Ph.D.

Senior Lecturer, Department of Psychology
University of Dundee, Scotland

Peter Willatts:

Everyone is gasping for coffee.  I’ll get you to look just a wee bit longer, and- that was the correct one.  So who got it?  Yes, I thought so:  people in the front.  Yes.  People in the back clearly are different, and there’s the evidence.

So that’s the test.  We have two measures.  The measures are the number of errors children make over a series of trials and the time it takes them to respond, to point to their first choice.  We measure that with a stopwatch; it’s a very effective way of measuring.

Here are the results.  The results for errors:  no differences in errors scored whatsoever.  You can see, we’ve also got data from a reference breast-fed group of children, and certainly, our formula-fed groups are well within the normal range, using breast-fed results as the standard.  So whether a child got LCPs, DHA, or ARA in infancy or not had no effect on their ability to solve a problem.  But if we look at speed, we found significantly faster responding in the children who received ARA and DHA in infancy.  They were about 20 percent faster.  They were more efficient at processing the information.  At this time, when they’re entering school, that’s important, because if you’re a little bit more efficient at mentally processing information, you’re going to do that a little bit better.  When you’re reading, you’re going to acquire numeracy that little bit easier.  This could well make an important difference.

So, final conclusions.  I hope I’ve been able to convince you that LCPs and especially DHA have positive effects on infant cognitive development.  I’ve focused on two main areas where we get the most consistent results:  speed of processing and attention control.  More importantly, these effects are not just confined to infancy; they persist.  They are long-term effects.  Dietary differences early in life are now shown to have long-term implications for later cognitive function.  In addition, we’ve seen from these new studies, and other trials I know are in progress, that omega-3 supplementation of both pregnant and breast-feeding mothers can improve cognitive development in their children.  I think the conclusion must be that both fish and seafood offering a natural source of omega-3 LCPs are going to be beneficial in promoting optimal cognitive growth.

Thank you very much for listening.

Introducing Speaker:

Thank you very much, Dr. Willatts.  You’ll see on our program we have a discussion period, and we’ll take questions for both of the speakers in this session.

Question:

Hello.  Yves Bastien, Fisheries and Ocean Canada.  My question was for Dr. Mozaffarian.  We know that salmon is, of course, a good source of omega-3 fatty acid, and I guess we do know also that one way of people to consume salmon is smoked salmon.  I’d like to know if you have found anything in the literature about, is there anything introduced in smoked salmon, like possible contaminants, that would change the risk/benefit analysis.

Dr. Mozaffarian:

I don’t know if I’m qualified to answer the question, because I really think I chose the wrong teddy bear.  I thought it was the one in the upper right corner; I thought it had square feet.

There is data from the USDA Food Nutrient Database that smoked salmon have a little bit less omega fatty acids.  They still do have omega-3 fatty acids, but they have a little bit lower content.  I think that gram for gram, there might be a less benefit compared to fresh salmon.  Again, we need so much weight of evidence to say that fish is beneficial, but we seem to require no weight of evidence to say that a contaminant is harmful, so I think that even if there were contaminants in the smoked salmon, some nitrates or something, I would find it extremely hard to believe that some small level of contaminants would outweigh the known, well-established, well-documented, very large—50 percent reduction in sudden death is not a small number, it’s better than any drug or surgery we have.  I think that the issue, again, would be, would the contaminant decrease the benefit to some extent, than if the contaminant weren’t there?  But I would find it very hard to believe that something that contains a reasonable amount of fish oil, either a supplement or smoked salmon or fresh fish, would not be net beneficial.

Question:

Joe Hibbeln from the NIH.  Dr. Mozaffarian, as we discussed in Toronto, I wanted you to elucidate if there was any level of high tuna intake—because tuna is probably the greatest fish deliverer of mercury in the U.S. diet—in which there was a greater risk of cardiovascular disease or death.

Dr. Mozaffarian:

I thank you.  I was worried you were going to ask me about N-3/N-6.

We grouped together tuna fish and other broiler-baked fish, because both had similar associations with lower risk.  The other broiler-baked fish were both associated with higher omega fatty-acid levels in the plasma and were also associated with lower risks.  On average, I think the other broiler-baked fish were- the oilier dark-meat fish like salmon, mackerel, herring, and they were associated with lower risk. But even the people who reported very high intakes of tuna fish—more than five servings per week—still had lower risk of coronary heart disease death, so there wasn’t a U-shape or anything like that, even at high levels.  I think, again, that makes sense that even if there might be mercury in the tuna, that they’re still getting the benefit of the fish oil, so net, they’re still getting benefit.

Question:

Dr. Willatts, what quantity of DHA in the mother’s diet or the baby formula were you referring to?

Dr. Willatts:

I knew someone was going to ask that question.  That’s the big question.  We really don’t know.  Variety of levels have been used.  There are very few of these studies, these supplementation studies, and I guess if you want to demonstrate improvement in children’s cognitive function, then the level should be measured against that degree of improvement.  So that’s a really hard question to answer at the moment.  Except there are a couple of interesting observations here.  The study in Norway involves women who generally you wouldn’t think to be at risk of having too low an intake of omega-3.  In fact, their initial levels were pretty high compared, for example, with mothers in the U.S.A.  Nevertheless, providing them with a supplement of cod liver oil did increase the levels.  It raised the levels in the infants.  So we don’t know what the upper limit is.  Given that enormous variation you see in breast milk, it’s really very hard to answer it.  Which is optimal?  Which is normal?  Is it the Japanese diet?  The Chinese?  The Israeli?  Or is it the diet in Kansas City?  It’s a very, very hard question to answer.  All we can say is that, relatively speaking, higher levels of provision of DHA and ARA to babies improves both visual and cognitive function.  Some of the studies that have been reported show no effects whatsoever, and I think undoubtedly the reason is the levels were too low.  We’ve missed out; we really do need some nice, controlled studies where we can get a clear dose/response relationship.  Those are expensive studies to do, because you need large numbers of subjects.

Question:

Dr. Willatts, Marcie ver Ploeg from Pittsford, New York.  A question for you:  Before you do your novelty testing with the young infants, how arduous and scientific is the process of figuring out what pictures you’re going to use, in terms of color or shapes, brightness, lightness, those kinds of factors?  Are you sure you’ve controlled for those?

Dr. Willatts:

Yes.  In fact, the examples I gave you come from the Fagan Test of Infant Intelligence—that’s a commercially available test developed by Joseph Fagan—where these issues have all been allowed for.  This is a very carefully selected set of pictures, equally balanced for interest.  Obviously, if you showed a highly interesting picture which was the normal one, babies would look at it spontaneously and you might mistakenly think they were recognizing, but in fact, they were not.  All that is very carefully controlled for.  Where researchers develop and use their own pictures, then you go through a pilot phase of testing to make sure that everything is equally attractive in its own right, before babies have been exposed to either of them. That would be how we would do it.

Question:

Dr. Mozaffarian, my name is Ron Johnson.  I’m with NOAA Fisheries in Seattle.  In your research, have you found any effect of increased DHA on serum cholesterol or serum LDL or HDL?

Dr. Mozaffarian:

Found an effect of fish oil on those parameters?  Is that your question?  I haven’t studied that, but that’s been well studied, and fish oil really has no effect on LDL or HDL cholesterol.  Very little effect.  At high doses, over a gram a day, it lowers triglycerides.  That’s one of the original reasons fish oil was thought to be cardio-protective, was that at three grams per day, you can lower triglycerides.  It’s actually an approved indication for prescribing fish oil supplements in the United States, is high triglycerides.  But for LDL and HDL and to some extent total cholesterol, there’s not much of an effect.  I think the effects of fish oil at regular dietary doses are very likely to have nothing to do with lipids.  It goes back to the paradigm I showed where the effects are really through other things:  arrhythmia, hemodynamics, inflammation, etc.

Question:

Sean Strain, University of Ulster.  A question for Dr. Willatts.  A couple of years ago, there was a meta-analysis published—I can’t remember the name of the authors; I’m from the back of the room here, so processing is not so good.  But they suggested or indicated that there was very little effect of fish oils, and DHA in particular, on term babies, that most of the effect was on pre-term.  Did these authors include the studies that you talked about in your presentation?

Dr. Willatts:

No, they haven’t.  One of the problems with- I’m just trying to think which meta-analysis you’re referring to.  Is this the one looking at visual development, do you recall?

Question:

Yes.  The visual development was about the only one that was showing any effect in term babies, but there was no other effects on early development.

Dr. Willatts:

That’s right.  Yes.  The meta-analysis on term infants suggests that there’s far less effect there.  On pre-term infants, you can see why there might be an effect, because a baby born pre-term is going to be missing out on that maternal supply, so it’s much more important to ensure that they do get an adequate supply.  However, one of the problems with some of the visual studies is that there is a whole variety of different methods used.  Some are much more sensitive than others.  Some of them have been carried out at different times in development, and there are clearly different periods where you will- there are plateaus in development for visual function.  If you’re testing a baby at the point where nobody is showing very much change, you’re not going to see differences.  There are some problems there.

In the case of cognitive function, there’s been a meta-analysis completed but not published, looking at studies where you’ve got common results.  These haven’t been included, because they haven’t been enough of them.  By that, I mean the researchers who looked at the outcomes of studies that have used a very general test of development, the Bailey Scales of Development, and particularly the Mental Development Index scores.  Now, the problem with all of those studies is, as a psychologist, that is the last test I would have thought of using to measure quite subtle differences in cognitive development, because it’s very heavily influenced by perceptual and motor function.  It really isn’t measuring these important cognitive abilities that I’ve been talking about today.

Yes, the meta-analysis showed there were no effects—I said that one wasn’t published—but what value is a meta-analysis were the researchers are using the wrong assessment?  So the answer is no, these haven’t been included.  There are simply not enough studies yet.  But I think as researchers- I know there are several studies of maternal supplementation underway, and the researchers are now beginning to use several of the tests of that I’ve been talking about.  I think it’s only a matter of time before we’ll have the evidence for a substantial meta-analysis.

Question:

A comment and a question.

Dr. Mozaffarian’s comment about LDL:  Actually, when patients who have hypertriglyceridemia and are treated with omega-3 fatty acids to lower their triglycerides, there frequently is a rise in LDL cholesterol.  There is a metabolic connection between- part of the reason they have a high triglyceride is that they have a blocked conversion from those particles to LDL.  When you remove that blockade, LDL levels can tend to come up at levels—not nutritional levels, as he points out—at three and four grams a day of omega-3, which is the therapeutic dose for triglyceride lowering.  So LDL can come up.  Whether that increases risk, nobody really knows.  Nobody suspects that it really does.

The question is to both of you.  You were talking about potential neurological effects of omega-3.  Certainly in the cardiovascular world, there has been a thought that some of the benefit of omega-3 might be on heart rate variability mediated by parasympathetic vagal tone.  Of course, that originates above the neck, so it’s not the heart, it’s the vagus.  I wonder if you’d comment on what you think of the possibility that omega-3 is actually affecting autonomic tone.

Dr. Mozaffarian:

Yes.  The measure is heart rate variability, and that’s a measure every normal person has.  Their heart rate varies during the day and at rest.  Basically, the more variable it is, the better; that’s the sign of a healthy heart, of a healthy nervous system affecting that heart.  People with heart disease have less heart rate variability, and heart rate variability predicts disease.  There are several studies, as you know, billed by Christensen et al., which suggest that fish oil increases heart rate variability.  Unfortunately, several studies from the same group, and one study from another group—from Gilan, from Martin Gitan’s [phonetic] group—did not show an effect on heart rate variability.  I think that the question is still up in the air.  We’ve done preliminary analyses in the cardiovascular health study looking at dietary levels, and so far, in these preliminary studies, dietary fish intake is strongly associated with heart rate variability.  I think it’s still an unanswered question, but an important one.

Joe Hibbeln:

Joe Hibbeln here, to answer your question with unpublished data.  From about 24 rhesus monkeys that we randomized to an infant formula containing 1 percent arachidonic and DHA emulating Japanese levels of breast milk compared to a placebo.  The supplement was given for just six months, and heart rate variability as a residual change was measured up to four years later in the rhesus monkeys.  The magnitude of improvement in heart rate variability was similar to the magnitude of effective ketamine on changing heart rate variability.  We do think that it is a residual neurological effect of supplementation that resulted in persisted improvements in heart rate variability four years later.

Dr. Willatts:

I could add just one little comment.  I can’t answer with regard to the possible mechanism, but we are currently getting measures of heart rate and heart rate variability in a study of 6-, 12- and 18-month old babies.  In fact, we’re finishing this study at the end of the month.  The last baby comes in next week.  And preliminary examination of the data suggests that at six months—certainly in the boys—we’ve got a relationship between DHA levels measured in cheek cells and heart rates, such that higher DHA is related to lower heart rate.  The data presented today for adults are very interesting, because the origin of this may well be much earlier on in infancy.  These are very preliminary results at the moment.  But as for the mechanism, I really have no idea.

Question:

Denny Morrow, Nova Scotia Fish Processors’ Association.  Canada is in the middle of an election campaign, and there will be lots of discussion about delivery of health care, and I suspect very little discussion about preventive health measures that might be taken.  I was struck by the comment that you made—I think it was Dr. Mozaffarian—about the benefits of increased omega oil intake being perhaps equivalent to some of our inoculation programs.  I wonder if you’d care to comment- in Nova Scotia, it used to be the practice that children in schools took cod liver oil in the morning.  I know when I was in Iceland a couple of years ago, everybody was having cod liver oil for breakfast.  It was there with the orange juice.  What kind of benefit—and maybe a cost benefit—could we get if we were to go back to fish oil, or go to fish oil, in our daycare centers, in our schools, as preventive medicine?

Dr. Mozaffarian:

The initial comment about the quality of adjusted life years was actually from the analysis of increasing fish intake, not fish oil supplements.  The analysis was that if you increase fish intake by 50 percent, they estimated the benefit to be on the level, again, of vaccination programs.  I’m a cardiologist, but I’m sort of an odd bird that I believe in prevention and simple things instead of sexy things.  So I believe in diet over supplements; I believe in preventing disease over angioplasty, etc.  So I think that I would start with increasing intake, and then for people that don’t want to eat fish, or for specific groups—for example, a woman who might want to become pregnant or people with heart disease—maybe supplements to boost the levels.

In terms of Canada and preventative health care and so forth, I think Canada is actually well ahead of the U.S. because they have a nationalized health care system and worrying about the overall health care budget- I don’t think they’re far advanced, but I think they’re ahead of the U.S.  There’s at least some interest.  I know at the University of Guelph, we were just there a couple of days ago and putting in functional foods, and putting DHA in milk and putting DHA in eggs, the government is funding that.  As far as I know, the U.S. government is not doing anything like that here.  So I think there is some initial interest in Canada in prevention to reduce health care costs.  If there was similar interest in the U.S., I think the health care costs would be- the cost/benefit ratio would be quite good.

Question:

Martin Breen from the Australian Seafood Industry.  It’s an abuse of question time to turn it into a statement, so there will be a question at the end of this.  It refers to the very important and fundamental question we had across the other side of the room earlier, as to why there isn’t more appropriate government funding for research into and promotion of the health benefits of seafood.  That’s a problem, of course, that extends beyond America.  One way to do that, when we look at communications later, might not be not just to communicate with potential consumers but to also communicate with the decision-makers, the politicians on your hill and ours.  I wonder if one way to do that mightn’t be to recruit heart-attack survivors, mothers of young children, and others to help carry that message to the politicians.  Here’s the question:  Do the speakers agree?

Dr. Willatts:

Yes, I think I do.  I think it is important to lobby, and I think it is important that the children should be a factor as well.  To encourage people to eat more fish- it’s very hard to know where to break into the cycle.  A lot of people just don’t like the flavor, don’t like the texture, and that comes from early childhood.  The schools probably are the way forward.  If children can be encouraged to include this food in their diet, and they take that back home, then I think that is one way in which you can begin to affect these lifestyle changes.  But it is chicken-and-egg.  Children are affected by the foods that are made available, and there’s good evidence that their interest in flavors is affected by the diet of the mother during pregnancy and breast-feeding.  So it’s a very hard area to break into.

Dr. Mozaffarian:

I have just a couple comments.  First, I agree with that, but I think that, based on our data with fried fish, I don’t think that fried fish sticks that are ubiquitous—I see it at my friends’ house all the time for their kids—is maybe the best answer.  I think part of it is, if you think back—in the U.S., anyway—if you think back to the history, the U.S. was founded by farmers, and there’s been interest for I don’t know how- well, it wasn’t founded, but there was a huge agricultural interest in the U.S., and the USDA and all those organizations for at least 50 years, if not 100 years, have been focused on helping farmers.  I think the historical weight of government has been to help farmers, to promote farming, to make food cheap.  The food in the U.S. is, I think, the cheapest per capita income in the world.  We have incredibly cheap food because of all these subsidies.  It’s only been about 40 years, 30 years, that there’s been any nutritional interest, really.  Forty years ago, it was deficiencies; we were trying to address deficiencies.  So I think this idea of food being healthy and seafood being healthy is so new, I think we’re just behind the curve.  We’re going against the historical weight of the government.  They’re not trying to waste their money purposefully; they just wanted to help the farmers.  I think that’s just been a historical thing.  We have to now think of, Add fish to that equation.

Introducing Speaker:

I want to thank our speakers very much.