Health
By: Taras Grescoe
Jan 17, 2009 - 2:08:20 PM
A single nutrient may have turned early humans into civilized man. Has stripping it from our diet given rise to cancer, diabetes, and other civilized diseases?
Fish, encapsulated: Colin Barrow, PhD, of Ocean Nutrition, the company that produces 60 percent of America's omega-3s. Studies have shown that regularly taking an omega-3 supplement can boost brain function and protect against heart disease. At the end of a residential cul-de-sac in Dartmouth, Nova Scotia, a driveway winds up a hill to the headquarters of Ocean Nutrition, a complex of buildings of mid-century vintage overlooking the tall-masted schooners and gray-hulled Canadian Navy destroyers in Halifax Harbour. Down the road, semi-trailers loaded with drums of oily yellow liquid pull up outside a newly built factory. Inside cavernous galvanized-steel hangars, the oil is blended with deionized water in 6,500-gallon tanks. The resulting slurry of micro-encapsulated oil is then pumped through a five-story spray-drier to remove the moisture. The final product is a fine-grained beige substance that looks like flour but is, in fact, a triumph of technology: smelly fish oil, transformed by industry into a tasteless, odorless powder. It will be used to spike everything from infant formula in China to the Wonder Bread and Tropicana orange juice on our supermarket shelves.
Ocean Nutrition is not manufacturing some Soylent Green for the new millennium. After seven years and $50 million of research, the company's 45 technicians and 14 PhDs have found a high-tech way of getting a crucial set of nutrients back into our bodies—compounds that, thanks to the industrialization of agriculture over the past half century, have been thoroughly stripped from our food supply without, until recently, it being realized by anyone. Now, an ever-growing body of research is showing that the epidemic of diseases associated with the Western diet—cancer, heart disease, depression, and much more—might be curtailed simply by restoring something we never should have removed from our diets in the first place: omega-3 fatty acids.
The Great Mistake
We are, it is often--and accurately—said, what we eat. Recent diet trends, from Atkins to South Beach, have put the emphasis on upping our intake of protein or cutting out carbohydrates. Meanwhile, cholesterol, saturated fats, and trans fats have been stigmatized, leading to the belief that waging a total war on fat is the best way to get a slimmer waistline and a longer life. But fats are as crucial to a healthy body as protein is; they end up holstered into the heart, protecting organs, and building the cells of the brain, an organ that is itself 60 percent fat. The key to good health lies not in ruthlessly striking fat from our diets, but in eating the best possible fats for our bodies. And a growing chorus of nutritionists agrees that those fats are omega-3s.
Certainly, you've read headlines trumpeting the ability of omega-3 fatty acids to boost brain function and protect against coronary heart disease. Hedging your bets, you may already have tweaked your diet, substituting beef or poultry for salmon or some other oily fish a few times a week. But, as a jaded observer of food trends, you may have wondered whether the new "heart-healthy" fats touted on the packaging of eggs, margarine, spaghetti, and frozen waffles are just a marketing ploy—the latest in a long line of miracle nutrients that, a few months or years hence, will prove to be nothing more than hype.
Lose the skepticism. This isn't the next oat bran.
Omega-3 molecules are a by-product of the happy meeting of sunlight, water, and carbon dioxide in the chloroplasts of terrestrial plants and marine algae. Not long ago, these fatty acids were an inescapable component of our diet. Back in the early 1900s—long before the arrival of bovine growth hormone and patented transgenic seeds--American family farms were perfect factories for producing omega-3s. Bucolic, sun-drenched pastures supported a complex array of grasses, and cattle used their sensitive tongues to pick and choose the ripest patches of clover, millet, and sweet grass; their rumens then turned the cellulose that humans can't digest into foods that we can: milk, butter, cheese, and, eventually, beef, all of them rich in omega-3s. Cattle used to spend four to five carefree years grazing on grass, but now they are fattened on grain in feedlots and reach slaughter weight in about a year, all the while pumped full of antibiotics to fight off the diseases caused by the close quarters of factory farms.
Likewise, a few generations ago, chickens roamed those same farms, foraging on grasses, purslane, and grubs, providing humans with drumsticks, breasts, and eggs that were rich in grass-derived omega-3s. Today, most American chickens are now a single hybrid breed—the Cornish—and are raised in cages, treated with antibiotics, and stuffed full of corn.
Our animal fats were once derived from leafy greens, and now our livestock are fattened with corn, soybeans, and other seed oils. (Even the majority of the salmon, catfish, and shrimp in our supermarkets are raised on farms and fattened with soy-enriched pellets.) So not only have good fats been stricken from our diets, but these cheap, widely available seed oils are the source of another, far less healthy family of fatty acids called omega-6s, which compete with omega-3s for space in our cell membranes. Omega-6s are essentially more rigid fatty acids that give our cells structure, while omega-3s are more fluid and help our bodies fight inflammation. Our ancestors ate a ratio of dietary omega-6s to omega-3s of approximately 1:1. The Western diet (the modern American and European eating pattern characterized by high intakes of red meat, sugar, and refined carbohydrates) has a ratio of about 20:1.
"The shift from a food chain with green plants at its base to one based on seeds may be the most far reaching of all," writes Michael Pollan in his prescriptive manifesto In Defense of Food. "From leaves to seeds: It's almost, if not quite, A Theory of Everything."
This shift began in earnest in the 1960s. Research on the links between cholesterol and saturated fats and coronary heart disease led health authorities to demonize lard, dairy products, and other animal-derived sources of fat. Meanwhile, new health guidelines lionized the polyunsaturated fats in vegetable oils and margarine (which is merely vegetable oil solidified via hydrogenation, a process that creates the dreaded trans fats).
Food processors were happy to play along: Polyunsaturated seed oils did not go rancid as quickly as omega-3s, which meant a longer shelf life for packaged foods. One form of fat in particular, omega-6–rich soybean oil, is now ubiquitous in processed foods. Soybeans, originally an import from East Asia, have become the second most valuable food crop in the United States. Genetically modified to resist pests, they are crushed to make high-protein meal for livestock, and the heavily subsidized industry has found ingenious ways of moving its product in the form of "soy isoflavones," "textured vegetable protein," "soy protein isolate," and the other novel ingre-dients lurking on the labels of processed foods. Look around your kitchen and you'll find soybean oil in everything from salad dressing to Crisco, from processed cheese to granola bars. If you are eating a processed food, chances are it contains soy. Twenty percent of Americans' calories now come from soybeans; the average person eats 25 pounds of the stuff a year. Just four seed oils—soybean, corn, cottonseed, and canola oil—account for 96 percent of the vegetable oil eaten in America today.
The spread of the seed-oil-rich Western diet around the world has been tracked by a statistical rise in the so-called diseases of civilization: asthma and arthritis, depression and Alzheimer's, heart disease and cancer, as well as metabolic disorders such as diabetes and obesity. Okinawans, of Japan, once had the longest life expectancy in the world. But with postwar American administration, which didn't end until 1972, residents of the Japanese prefecture switched to a Western diet rich in meat and seed-based vegetable oils (think Spam, McDonald's hamburgers, and margarine). As a result, they experienced a precipitous rise in cancer, diabetes, and cardiovascular diseases. Western eating habits proved hard to shake, and 47 percent of Okinawan men are still considered obese, twice the rate of the rest of Japan.
According to a 2003 study published in the World Review of Nutrition and Dietetics, urban Indians who have adopted seed-oil-rich diets succumb to heart disease and chronic illnesses at a much higher rate than village dwellers who eat a "poor man's diet" that is high in mustard oil, which is relatively high in omega-3s. It is believed that, in the 1960s, Israelis enthusiastically adopted an ostensibly heart-healthy diet rich in polyunsaturated fats from vegetable oils; now heart disease, high blood pressure, and diabetes are ubiquitous, and rates of cancer are higher than in the United States.
In 1970, intrigued by reports that Eskimos rarely die from heart disease, two Danish scientists flew to Greenland and charmed blood samples from 130 volunteers. Hans Olaf Bang and Jørn Dyerberg discovered that the Inuit people still got most of their calories from fish, seal, and whale meat. Despite their high cholesterol intake, the Inuit had a death rate from coronary disease that was one-tenth that of the Danes, enthusiastic pork eaters who have been known to butter even their cheese. And diabetes was almost non-existent among the Inuit. Bang and Dyerberg found strikingly high levels of omega-3s and relatively low amounts of omega-6s in the Inuit blood samples. In 1978, they published a groundbreaking paper in The Lancet, establishing the link between omega-3 consumption and lower rates of coronary heart disease. It initiated a paradigm shift among nutritionists, one that is only now truly influencing official dietary policy around the world.
"There has been a thousandfold increase in the consumption of soybean oil over the past hundred years," says Joseph Hibbeln, MD, acting chief of the section on nutritional neurosciences at the National Institutes of Health in Bethesda, Maryland. The result, he states, is an unplanned experiment in brain and heart chemistry, one whose subject is the entire population of the developed world. In a series of epidemiological studies, Dr. Hibbeln showed that populations that consume high levels of omega-3s in the form of seafood are the least afflicted by the major diseases associated with the Western diet.
Among the Japanese, who each eat an average of 145 pounds of fish a year, rates of depression and homicide are strikingly low. Meanwhile, men who live in landlocked nations such as Austria and Hungary, where fish consumption is respectively 25 pounds and nine pounds per capita, top the global charts in suicide and depression. Despite the fact that the Japanese smoke like fiends, struggle with high blood pressure, and eat a hundred more cholesterol-rich eggs a year per person than Americans do, they boast enviably low rates of cardiovascular disease, as well as the longest life span on the planet, an average of 81 years…three years longer than that of Americans. And while it's true that the Japanese consume soy in the form of tofu, miso, and soy sauce, the way it is prepared--precipitated or fermented--is far healthier than the raw, mineral-blocking phytate estrogen and omega-6-rich versions consumed by Americans.
Dr. Hibbeln is convinced that the key to the average Japanese citizen's longevity is omega-3 fatty acids; levels in Japanese bloodstreams average 60 percent of all polyunsaturates. After half a century of favoring seed-based vegetable oils, the level of omega-3s in American bloodstreams has fallen to 20 percent of polyunsaturates. "We have changed the composition of people's bodies and brains," says Dr. Hibbeln. "A very interesting question, to which we don't yet know the answer, is to what degree has the dietary change altered overall behavior in our society?"
Lately, the answers have been coming in thick and fast. In one study of 231 inmates medicated with fish oil in a British prison, assaults dropped by a third. Comparing homicide rates in five countries, Dr. Hibbeln found that the rising consumption of omega-6 fatty acids correlated with a hundredfold increase in death by homicide, even though access to firearms went down in all the countries surveyed except the United States. A paper published in the Journal of the American Medical Association concluded that even a modest increase in the consumption of omega-3–rich fish reduced the risk of coronary death by 36 percent. A 2007 study by the National Institutes of Health found a positive correlation between mothers' consumption of omega-3s during pregnancy and the fine motor skills and verbal IQs of their children. Increasing the amount of omega-3s in your diet might even reverse obesity: Omega-6s are, in the words of one researcher, "remarkable boosters of adipogenesis," which is to say the formation of fatty -tissues. Animals that are fed diets high in omega-6s gain far more weight from the same amount of calories than their grass-fed counterparts, and that hard-to-lose fat in the middle-aged paunch, it turns out, is mostly omega-6s. A higher intake of omega-3 has been shown to positively affect ailments as diverse as stroke, allergies, dementia, and dyslexia.
"Men in their forties and fifties can nearly reverse their risk of dying from sudden cardiac death by eating fish at least three times a week," says Dr. Hibbeln. "And if they want to live -longer and happier lives, there's substantial data that they should increase their body composition of omega-3s." Your family doctor can test your ratio of omega-6 to omega-3, or you can do it yourself. (Your Future Health sells test kits on its Web site, yourfuturehealth.com.)
How could a simple change in dietary fat have such a huge impact on so many aspects of our health? The answer lies in the nature of two specific forms of omega-3s, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), which are especially rich in seafood.
Not all omega-3 fatty acids, it turns out, are created equal.
The Rise of Humanity
Stephen Cunnane, PhD, is an ideal poster boy for a high omega-3 diet. Tall, energetic, and trim, this researcher in brain metabolism at Quebec's University of Sherbrooke lacks any sign of the paunch you might expect in a man of 55 years. His secret, he confides, is lots of exercise and at least two servings of omega-3–rich fish a week.
Cunnane believes that omega-3s, and specifically DHA and EPA, are the crucial nutrients that permitted proto-humans with brains the size of a chimpanzee's to become chattering, tool-using Homo sapiens. DHA has a cylindrical shape and can compress and twist like a Slinky, switching between hundreds of different shapes billions of times a second. The molecule is particularly abundant in the tails of rattlesnakes, the wings of hummingbirds, the tails of sperm, and the retinas and brain cells of people who eat fish. A neuron that is high in DHA molecules is virtually liquid, allowing for more effective reception of serotonin, dopamine, and other crucial neurotransmitters. In test subjects, this heightened neuroplasticity has been linked to better vision and eye-hand coordination, better mood, enhanced general movements, and an increased capacity for sustained attention. EPA is no less crucial: It reduces blood clotting and dampens the inflammatory response in tissues. Such chronic inflammation is suspected to be at the root of most of the so-called diseases of civilization, from Alzheimer's and depression to heart disease and cancer.
While it's true that terrestrial plants are good sources of omega-3s, the fatty acid most present in land-based species is alpha-linolenic acid (ALA). Essential for good health, ALA can be found in fruits, vegetables, and some seeds, among them lettuce, leeks, purslane, kale, broccoli, blueberries, hemp, chia, and flaxseed. ALA is especially rich in plants that grow in intense light, and the fatty acid is thought to help the plants recover from sun damage. Though the human body is capable of turning ALA into DHA and EPA through a series of enzymatic reactions, it is not particularly good at it: Less than 1 percent of the ALA we get from vegetable sources ultimately becomes DHA and EPA. The ocean is the world's richest source of DHA and EPA, particularly from plankton-eating oily fish such as sardines, mackerel, and herring.
Recently discovered archaeological evidence suggests that around 2 million years ago, early hominids, the ancestors of modern humans, left the forests to live on the wooded edges of huge brackish lakes and estuaries in what is now Africa's Rift Valley. Prehistoric middens found in Kenya and Zaire are filled with shells and headless catfish skeletons, evidence that these proto-humans were taking full advantage of the easily gathered protein—and, incidentally, omega-3 fatty acids—at one of the world's first all-you-can-eat seafood buffets. Around the same time, hominid brains began to grow, swelling more than twofold from 650 grams in Homo habilis, the first tool-using hominid, to 1,490 grams in the early ancestors of Homo sapiens. "Anthropologists usually point to things such as the rise of language and tool making to explain the massive expansion of early hominid brains," says Cunnane. "But this is a catch-22. Something had to start the process of brain expansion, and I think it was early humans eating clams, frogs, bird eggs, and fish from shoreline environments."
The missing link: New evidence suggests that an omega-3–rich diet may have helped make us human. Scientists such as Stephen Cunnane, PhD, (pictured here) believe our ancestors fished long before they settled the plains. Seafood is especially rich in the minerals zinc, iodine, copper, iron, and selenium, all of which are essential for fetal brain growth and good brain function in adults, and may have kick-started the process of explosive neural growth. This shore-based theory of early human evolution, laid out by Cunnane in his book Survival of the Fattest and championed by the British brain chemistry expert Michael Crawford, challenges the prevailing savannah and woodland theories, which pinpoint hunting and scavenging as the motive force in brain evolution. The Aquatic Ape Theory is a more controversial version of the shore-based scenario. Propounded by Sir Alister Hardy and Elaine Morgan in the United Kingdom, it seeks to explain such diverse phenomena as bipedalism and the streamlined human torso by positing an aquatic phase to human evolution, in which hominids spent a good percentage of their waking lives wading and swimming in search of seafood.
Cunnane's account has the advantage of explaining some of the more puzzling attributes of Homo sapiens. Why, for example, are we the only primates whose babies are born with more than a pound of subcutaneous fat, and whose fetuses actually float? And why, unlike elephants, rhinos, and other mammals whose brains actually shrank over the generations, did our ancestors' gray matter undergo explosive and sustained growth in the past 2 million years?
EPA and DHA, Cunnane insists, work in synergy; what is good for the heart also tends to be good for the brain. "Even if you don't change the composition of your brain by getting more DHA," says Cunnane, "the vessels are the things that supply oxygen and nutrients to your brain, and they require omega-3 fatty acids for optimal function as well. For blood pressure regulation, for controlling your platelet function, your clotting tendency, the rhythm of your heart, you need omega-3 fatty acids."
Cunnane shows me a photo of an image carved into buff-colored sandstone. "This was found in a cave in France. It must have been one of the Sistine Chapels of the drawing world at the time." It is a highly naturalistic rendition of a salmon, down to gill flaps and hooked mandible. Evidence of early fish eating, jaw-dropping in its technical sophistication, the image is 22,000 years old. An interesting footnote to Cunnane's theory is that our seafood-eating Cro-Magnon ancestors, including the master sculptor responsible for this bas-relief, might well have been smarter than we are. Fossil evidence shows that the Cro-Magnons, though their bodies were smaller than those of Neanderthals, had brains about 200 grams heavier than modern humans'. Humanity's relatively recent creep away from seafood-rich shorelines, Cunnane believes, explains everything from the 20 percent of American women who are iron deficient to the dangling goiters of people living in mountainous regions. (If iodine hadn't been added to table salt 80 years ago, cretinism, a deficiency typified by severely stunted mental growth, would be endemic in most developed countries.) Until the American Revolution, 98 percent of the population lived along rivers and oceans. Leaving the coasts might be a slow-motion public-health disaster. Deficiencies of DHA and the brain-selective minerals abundant on shorelines, speculates Cunnane, affect the performance of the modern human brain and, uncorrected, might eventually cause brains to shrink.
"Adaptation will be necessary," he concludes in Survival of the Fattest, "either by making supplements more widely available or by moving back to the shorelines, or we will conceivably face evolutionary processes that could eventually reduce cognitive capacity."
In other words, our cod-liver-oil–loving grandmothers had it right: Fish really is brain food. And our disastrous decision to replace the omega-3s in our diet with omega-6s might be all the proof anybody needs that, as a species, Homo sapiens are getting demonstrably dumber.
The Future of Fish
Colin Barrow, PhD, Ocean Nutrition's vice president of research and development, has any number of ways of getting omega-3s into his diet. He could, he points out, spread specially formulated Becel margarine onto DHA- and EPA-spiked Wonder Bread and wash it down with omega-3 supplemented Danone liquid yogurt. Instead, he prefers to take his omega-3s neat: He stirs a tablespoon of pure powdered fish oil into his morning juice.
A tall, soft-spoken New Zealander with a ginger beard and a long-toothed smile, Barrow has used the expertise gained from a PhD in chemistry and marine natural products to develop the process that allowed Ocean Nutrition to reintroduce omega-3s into packaged foods.
"The process is called microencapsulation," says Barrow, "and it was originally used for delivering ink in the cartridges of ink-jet printers." If you increased the size of a grain of Ocean Nutrition's microencapsulated powder to that of a basketball, it would be filled with Ping-Pong-ball–size agglomerations of oil encased in gelatin. Each particle is like a microscopic fish-oil capsule, allowing the powder to be added to food without changing the food's taste. Without a protective coating to prevent oxidation, the omega-3 in a glass of orange juice would stink like a sardine tin left out in the sun. Ocean Nutrition has taken any hint of fishiness out of fish oil—an essential move in the notoriously seafood-averse North American market.
The source of Ocean Nutrition's meticulously deodorized oil is, ultimately, a fish. Namely, Engraulis ringens, the Peruvian anchoveta, a small schooling species that lives in the relatively unpolluted waters off the west coast of South America. The process starts when fishing boats encircle the vast schools with purse-seine nets and bring the catch back to barges. Under the close supervision of rabbis, who are there to ensure that no squid, shellfish, or other nonkosher species remain in the nets, billions of fish are sucked through a pipe to onshore processing plants. There, the anchoveta are heated to 85 degrees Celsius, ground with an auger, and pulverized with a hydraulic screw to extract the oil. The oil is then distilled and filtered through clay to eliminate all traces of mercury, dioxins, and other persistent organic pollutants, those nasty toxins that can cause developmental and long-term neurological problems in consumers of tuna and farmed salmon. Transported by container ship through the Panama Canal, the oil arrives in Nova Scotia, where it is further concentrated and refined. Some of the oil ends up on the shelves of Walmart, Walgreens, and other major retailers that package it in their house-brand capsules. The rest, in powdered form, goes to the likes of PepsiCo and Unilever, who mix it into packaged foods. Ocean Nutrition now supplies 60 percent of the North American fish-oil market.
For anybody concerned about the future of the oceans, Ocean Nutrition's sourcing policies are good news. With big predatory species such as tuna, sharks, and swordfish already fished to 10 percent of their former abundance, and marine ecologists predicting the collapse of most major fisheries by the year 2048, conservationists have expressed concern about what kind of impact the widespread use of omega-3 supplements could have on the world's remaining fish stocks. Fortunately, the Peruvian anchoveta fishery—one of the world's largest—is in no imminent danger of collapse.
"These fish have been harvested in a highly regulated way, in very pristine waters, for more than 50 years," says Ian Lucas, Ocean Nutrition's executive vice president of marketing, "and the biomass is actually expanding." Fish oil is an industrial by-product of the fish-meal industry, which supplies feed for livestock and farmed shrimp and salmon. "It's going to take a long, long time before the fish-oil industry actually causes more fishing to happen," says Lucas. But according to Daniel Pauly, PhD, a leading authority on the decline of the world's fisheries at the Fisheries Centre at Vancouver's University of British Columbia, stocks of Peruvian anchoveta can fluctuate wildly; there was a temporary collapse in the 1970s and again in the 1980s. To forestall future problems, Pauly believes the fishery needs to be even more strictly monitored and regulated than it is today.
As word spreads of omega-3's benefits, so does fish-oil consumption. Lucas says that the share of omega-3 fatty acids in the supplement market has been growing by 30 percent a year for the past five years. Though alternative sources of fish oils exist, some are clearly more ecologically questionable than Peruvian anchoveta. A Virginia-based company called Omega Protein nets a schooling fish called menhaden off the mid-Atlantic coast; its -menhaden-based fish oil may now be added to 29 different categories of food. The fishery has been criticized because menhaden is a keystone species in the food chain of the East Coast; the fish feed by filtering algae from the water, and, in their absence, microscopic plankton have proliferated, creating the harmful algae blooms and dead zones that plague places such as Chesapeake Bay.
Barrow escorts me into a lab and shows me a 10-liter glass fermentation tank bristling with hoses and filled with a cloudy, swirling, foam-topped liquid. In its search for alternative sources of omega-3s, Ocean Nutrition has gathered a DHA-rich alga from an undisclosed location in Canada. In the United States, a company called Martek has already patented its own DHA-producing alga called Crypthecodinium cohnii, which is grown in massive multistory tanks in South Carolina; much of the infant formula in North America is now supplemented with Martek's patented Life's DHA.
"The product is good," says Barrow, "but it's really expensive, and they can't get their microorganisms to produce EPA. Our organism is a really good producer; we can get it to express about 8 percent EPA." This may be the future of omega-3s: an essential nutrient grown in tanks, sparing the world's fish stocks from overharvesting.
If Ocean Nutrition's better-living-through-chemistry approach to good nutrition strikes you as somewhat sinister, there is a straight-forward alternative to microencapsulated fish oil. The best way to get high-quality DHA and EPA into your body, it turns out, is the old—fashioned way: Eat more seafood, especially shellfish and smaller fatty fish such as herring, mackerel, anchovies, and sardines.
"You should eat vegetables and fruits, of course, and get exercise," advises Cunnane, "but you have to eat fish. You can take fish-oil capsules, but part of the point is to enjoy the experience of eating. So buy the best fish you can afford." Seafood also has the edge on omega-3 capsules because it includes the brain-selective minerals zinc, iron, copper, iodine, and selenium, cofactors our bodies need to make optimal use of EPA and DHA.
And now, full disclosure: As part of the research for a book I was writing about the sustainability of seafood in our world's oceans, I have radically increased my intake of omega-3s over the past two years. I've been taking three fish-oil capsules a day (a combined total of 1,800 milligrams of DHA and EPA), and having at least four fish meals a week. Early on, I saw a marked change in my alertness and capacity for sustained attention. But it wasn't until I started diminishing the amount of omega-6s in my diet that I started to lose weight. In the past year, I've shed five pounds and reversed the first swellings of a nascent potbelly.
The goal is not to "nix the six" completely, as the writer of one diet book puts it; after all, omega-6s are essential to good health. But getting an adequate supply is hardly a challenge; they are omnipresent in our food, and we would all be better off if our diets were closer to the 1:1 omega-6 to omega-3 ratio of our hunter-gatherer ancestors.
For me, the easiest change has been ridding my kitchen of such high-omega-6 fats as sunflower oil, corn oil, soybean oil, and margarine; I now favor olive oil, canola oil (a polyunsaturate, but one that is high in omega-3s), and butter. I have lately become an assiduous reader of food labels. Polyunsaturated fats, I now know, are usually synonymous with omega-6 fatty acids, which seem to have worked their way into virtually all the processed foods in the supermarket. It is much healthier to seek out monounsaturated fats like olive oil, and even avoid processed foods altogether. Even some forms of fish are high in omega-6s, especially fried fish sticks, fast-food sandwiches, and farmed catfish, tilapia, and salmon (whose feed is now spiked with large amounts of soy).
And those omega-6 capsules sold in health-food stores are worse than useless: Adding additional omega-6s to your diet defeats the whole purpose of the exercise. When shopping for an omega-3 capsule, I typically look for the brand with the highest levels of DHA and EPA, usually about 400 milligrams of EPA and 200 milligrams of DHA.
Omega-3s aren't a quick fix like Advil, or even, for that matter, Prozac, which takes several weeks to change brain chemistry. Omega-3s take at least three months to harness themselves into heart cells, for example. I can't be certain about improvements in my cardiovascular health, but since I started loading up on DHA and EPA, I feel as if I've upgraded my brain. My energy is high, and I feel strangely unflappable, like I've gained some kind of unbeatable equilibrium. My body feels different too, as though my fat and muscle have been redistributed to more useful places. Navigating among the omega-6–fattened hordes, I feel lean and swift, like a tuna darting among sea cows.
So, by all means, keep swallowing those omega-3 capsules. But here's an even better idea: Seek out grass-fed beef, free-range chickens and their eggs, the best olive oil, canola oil, and butter you can find, and lots of fish and shellfish, preferably small wild-caught species from clean waters. In other words, if you are looking for a guiding principle, keep it simple and eat like your ancestors ate.
Better Know Your Fish: A species guide to the highest levels of omega-3s
There's no question: Choosing seafood these days isn't easy. Some species (e.g., bluefin tuna and Atlantic halibut) have been fished to near extinction. Others (swordfish, farmed salmon) can contain nasty persistent organic pollutants (dioxins, PCBs) or be so high in mercury you might as well be chewing on a thermometer. (Go to gotmercury.org for an easy-to-use tool that shows where your favorites stand.) Generally, small, oily ocean fish (herring, mackerel) are low in toxins and score highest in omega-3s, while freshwater species (catfish, tilapia) have the lowest level of omega-3s because they don't eat the beneficial ocean plankton that bioaccumulates into this nutrient. Here's a countdown of the omega-3 levels in a three-ounce serving of common seafoods, from salmon to lobster. An important note: Farmed fish fattened with soy, as well as breaded and fried fish, can be as high in omega-6s as a cheeseburger (see next page). And a final word to the wise: When it comes to canned fish, go for sardines and tuna packed in water or olive oil rather than high-omega-6 vegetable oils.
Species: Omega-3s (in milligrams)
| Salmon (farmed, Atlantic) | 1,930* | |
| Herring (Atlantic) | 1,820 | |
| Anchovy (canned, in olive oil, drained) | 1,760 | |
| Sardine †| 1,260 | |
| Mackerel (Atlantic) | 1,120 | |
| Toro (bluefin tuna) | 1,104 | |
| Trout †(wild) | 1,000 | |
| Salmon (wild, Pacific) | 950 | |
| Striped Bass | 840 | |
| Mussel | 826 | |
| Swordfish | 696 | |
| Halibut (Atlantic) | 470 | |
| Crab | 377 | |
| Scallop | 336 | |
| Oyster | 329 | |
| Shrimp †| 284 | |
| Tuna †| 280 | |
| Snapper | 270 | |
| Cod †(Pacific) | 239 | |
| Eel | 188 | |
| Tilapia †| 166 | |
| Catfish †(farmed) | 151 | |
| Cod (Atlantic) | 145 | |
| Lobster | 73 |
* Farmed salmon, usually sold as Atlantic, is high in both omega-3s and undesirable omega-6s.
†This denotes fish with higher omega-6 to omega-3 ratios.
Source: USDA Nutrient Database, nal.usda.gov/fnic/foodcomp/search
http://www.bestlifeonline.com/cms/publish/health/Omega-3-Nutrient.php
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