Heart attacks seem increasingly common in western countries. In part it may be simply that the average age of westerners is increasing, and hearts wear out. In part it may be poor diets which weaken those old hearts more. There are good arguments that one should learn to own and operate a heart when young so that it will last longer. Exercise is good and so is attention to diet. This is a highly contentious subject that attracts quacks with diet books and wellness centers, making it difficult, and in the end disgusting, to contemplate. A pox on all their houses.

There's a semi-interesting debate about dietary substances, food extracts, being used as medicine.

ROME — Every patient in the cardiac care unit at the San Filippo Neri Hospital who survives a heart attack goes home with a prescription for purified fish oil, or omega-3 fatty acids. . .

But in the United States, heart attack victims are not generally given omega-3 fatty acids, even as they are routinely offered more expensive and invasive treatments, like pills to lower cholesterol or implantable defibrillators. Prescription fish oil, sold under the brand name Omacor, is not even approved by the Food and Drug Administration for use in heart patients. . .

Because prescription fish oil is not licensed to prevent heart disease in the United States, drug companies may not legally promote it for that purpose . . .

So community doctors do not learn how to use the drug. Lack of F.D.A. approval also means that insurers will not pay for treatment with Omacor. Approval from the agency for the use of the drug in heart disease is not expected soon. . .

Why not?

In a large number of studies, prescription fish oil has been shown to improve survival after heart attacks and to reduce fatal heart rhythms. The American College of Cardiology recently strengthened its position on the medical benefit of fish oil, although some critics say that studies have not defined the magnitude of the effect. . .

In the largest study of fish oil — conducted more than a decade ago — Italian researchers from the Gissi Group (Gruppo Italiano per lo Studio della Sopravvivenza nell’Infarto), gave 11,000 patients one gram of prescription fish oil a day after heart attacks. After three years, the study found that the number of deaths was reduced by 20 percent and that the number of sudden deaths by 40 percent, compared with a control group.

Later studies have continued to yield positive results, although some scientists say there are still gaps in knowledge.

This summer, a critical review of existing research in BMJ, The British Medical Journal, “cast doubt over the size of the effect of these medications” for the general population, said Dr. Roger Harrison, an author of the paper, “but still suggested that they might benefit some people as a treatment.”

It's not a miracle drug that has large, immediate and easily quantifiable effects. Its use as a medicine after heart attacks is not yet well understood. It can't hurt, it may help, many believe in it, and in some countries it is common. I suggest that the more important role of omega-3 fatty acids is in prevention rather than treatment. Other's agree.

Dr. Harrison said he believed that people should generally increase their intake of omega-3 acids, best done by eating more fish.

Still, he acknowledged that it was difficult to eat foods containing a gram of omega-3 acids each day. “If you ask me do I take omega-3 supplements every day, then, embarrassingly, the answer is yes,” said Dr. Harrison, a professor at Bolton Primary Care Trust of the University of Manchester in England.

“I, too, am caught up in this hectic world where I have little time to shop and prepare the healthy foods I know I should be eating,” he said. . .

The American College of Cardiology now advises patients with coronary artery disease to increase their consumption of omega-3 acids to one gram a day, but it does not specify if this should be achieved by eating fish or by taking capsules. But over-the-counter preparations of fish oil have much less rigorous quality control and are often blends of the two fish oils know to be beneficial in heart disease with other less useful fatty acids.

Omega-3 fatty acids are not mysterious substances only found in fat fishes. They are everywhere but in small quantities. All your greens have them and some seeds and nuts (flax, walnuts) have them in modestly high concentrations. In many cases what is available in these foods is a precursor that is converted in the body. The conversion rate is variable, often low, depending on the presence of other nutrients such as certain vitamins.

Worse perhaps, fatty fishes are sometimes (often?) laced with heavy metals such as mercury. They are top predators who concentrate substances from their prey, not just omega-3 fatty acids but whatever chemicals they have consumed. Wild fishes may or may not be OK. Farmed fishes may not have the toxins but may also not have the omega-3 fatty acids depending on what they were fed in confinement. Equally worrisome is the over-exploitation of fish stocks world wide. Not only are wild stocks depleted it seems that farmed fishes spread parasites and perhaps diseases to the wild, and escapees may weaken the gene pool.

An arguably better source is from ruminants, such as cattle and goats, that are raised on a natural diet of greens rather than grains. They have much higher levels of omega-3 fats than grain fed animals. Still, getting a gram of omega-3 acids each day seems daunting. Long ago in a far away blog post I discussed this with Randall "FuturePundit" Parker and Oliver "Nature Magazine" Morton.

The conversation continues with Randall asserting that:

When lipid content is standard, a serving of grass-fed beef would provide 88.5 mg of omega-3, roughly 13% of the RDI for EPA/DHA

Unless you wnat to eat 6 or 7 servings of beef a day (which is not a good idea) grass fed beef just isn't going to get you there. . .

Fish is still the only game in town.

Not really.

Drinking just half a pint a day of organic milk as part of a healthy balanced diet gives a useful additional source of this Omega 3 fatty acid, as it could provide approximately 10% of the UK’s Daily Reference Value3 of essential n-3 fatty acid, alpha-linolenic acid.

Organic cheese is an even better source, with a matchbox sized piece of organic cheese providing up to 88% of your RDI of this Omega 3 fatty acid.

Organic isn't the issue since you could have certified organic grain fed animals and thus low omega-3. The issue is grass fed since the omega-3 comes from greens. That's where the little fishes get it and eating the little fishes is where the big oily predator fishes get it. Somebody needs to eat their greens, though some nuts (such as walnuts) have good amounts too.

People can't eat and digest enough greens to get a significant amount, but fishes or ruminants can concentrate it for them. Ruminants do this directly from the foods they eat while most oily fishes are predators that concentrate previously concentrated oils. This is the problem with toxins since each level up the food chain concentrates toxins as well as omega-3. The older a fish is and the higher in the food chain the greater the chance of concentrated toxins.

It seems possible to get non-toxic fish if you are careful. It seems possible to get omega-3 rich meat and dairy if you are selective and specify grass fed. If you do then it's easy to get the RDI of omega-3 while eating a varied diet.

Given all the trouble with fishes you may be wiser to care for your heart by seeking out meat and dairy products from grass fed ruminants, and seeds and nuts that have higher levels of precursors. Say Cheese 8-)

Update:

It isn't just heart health, it's brain health too. [via Instapundit -> Clayton Cramer's Blog -> Guardian]

Mechanisms by which aggressive and depressive disorders may be exacerbated by nutritional deficiencies in omega-3 fatty acids are considered. Early developmental deficiencies in docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) may lower serotonin levels at critical periods of neurodevelopment and may result in a cascade of suboptimal development of neurotransmitter systems limiting regulation of the limbic system by the frontal cortex. Residual developmental deficits may be manifest as dysregulation of sympathetic responses to stress including decreased heart rate variability and hypertension, which in turn have been linked to behavioral dysregulation. Little direct data are available to disentangle residual neurodevelopmental effects from reversible adult pathologies. Ensuring optimal intakes of omega-3 fatty acids during early development and adulthood shows considerable promise in preventing aggression and hostility.

The argument that modern diets stunt children's brains and lead to an increase in violence is mostly correlation, but they are working on causation.

Over the last century most western countries have undergone a dramatic shift in the composition of their diets in which the omega-3 fatty acids that are essential to the brain have been flooded out by competing omega-6 fatty acids, mainly from industrial oils such as soya, corn, and sunflower. In the US, for example, soya oil accounted for only 0.02% of all calories available in 1909, but by 2000 it accounted for 20%. Americans have gone from eating a fraction of an ounce of soya oil a year to downing 25lbs (11.3kg) per person per year in that period. In the UK, omega-6 fats from oils such as soya, corn, and sunflower accounted for 1% of energy supply in the early 1960s, but by 2000 they were nearly 5%. These omega-6 fatty acids come mainly from industrial frying for takeaways, ready meals and snack foods such as crisps, chips, biscuits, ice-creams and from margarine. Alcohol, meanwhile, depletes omega-3s from the brain.

To test the hypothesis, Hibbeln and his colleagues have mapped the growth in consumption of omega-6 fatty acids from seed oils in 38 countries since the 1960s against the rise in murder rates over the same period. In all cases there is an unnerving match. As omega-6 goes up, so do homicides in a linear progression. Industrial societies where omega-3 consumption has remained high and omega-6 low because people eat fish, such as Japan, have low rates of murder and depression.

Of course, all these graphs prove is that there is a striking correlation between violence and omega 6-fatty acids in the diet. They don't prove that high omega-6 and low omega-3 fat consumption actually causes violence. Moreover, many other things have changed in the last century and been blamed for rising violence - exposure to violence in the media, the breakdown of the family unit and increased consumption of sugar, to take a few examples. But some of the trends you might expect to be linked to increased violence - such as availability of firearms and alcohol, or urbanisation - do not in fact reliably predict a rise in murder across countries, according to Hibbeln. . .

Essential fatty acids are called essential because humans cannot make them but must obtain them from the diet. The brain is a fatty organ - it's 60% fat by dry weight, and the essential fatty acids are what make part of its structure, making up 20% of the nerve cells' membranes. The synapses, or junctions where nerve cells connect with other nerve cells, contain even higher concentrations of essential fatty acids - being made of about 60% of the omega-3 fatty acid DHA.

Communication between the nerve cells depends on neurotransmitters, such as serotonin and dopamine, docking with receptors in the nerve cell membrane.

Omega-3 DHA is very long and highly flexible. When it is incorporated into the nerve cell membrane it helps make the membrane itself elastic and fluid so that signals pass through it efficiently. But if the wrong fatty acids are incorporated into the membrane, the neurotransmitters can't dock properly. We know from many other studies what happens when the neurotransmitter systems don't work efficiently. Low serotonin levels are known to predict an increased risk of suicide, depression and violent and impulsive behaviour. And dopamine is what controls the reward processes in the brain.

It's not only what you eat you are, it's also what she ate you are.

Hibbeln's theory is that because the omega-6 fatty acids compete with the omega-3 fatty acids for the same metabolic pathways, when omega-6 dominates in the diet, we can't convert the omega-3s to DHA and EPA, the longer chain versions we need for the brain. What seems to happen then is that the brain picks up a more rigid omega-6 fatty acid DPA instead of DHA to build the cell membranes - and they don't function so well.

Other experts blame the trans fats produced by partial hydrogenation of industrial oils for processed foods. Trans fats have been shown to interfere with the synthesis of essentials fats in foetuses and infants. Minerals such as zinc and the B vitamins are needed to metabolise essential fats, so deficiencies in these may be playing an important part too.

There is also evidence that deficiencies in DHA/EPA at times when the brain is developing rapidly - in the womb, in the first 5 years of life and at puberty - can affect its architecture permanently. Animal studies have shown that those deprived of omega-3 fatty acids over two generations have offspring who cannot release dopamine and serotonin so effectively.

"The extension of all this is that if children are left with low dopamine as a result of early deficits in their own or their mother's diets, they cannot experience reward in the same way and they cannot learn from reward and punishment. If their serotonin levels are low, they cannot inhibit their impulses or regulate their emotional responses," Hibbeln points out.

If you have a bun in the oven, eat well.