Via thriftymom this morning, a link to this article, which I’d give 4 out of 5 stars:
The Vanishing Youth Nutrient
Science writer Susan Allport unravels why the disappearance of omega-3s from our diet may be responsible for the epidemics of obesity, heart disease, cancer. Oh, and wrinkles, too.
In terms of her explanation of the omega-6 vs. omega-3 problem, it’s excellent.
Since 1909, according to the USDA, Americans have more than doubled their daily intake of omega-6s–from about 7 grams to around 18. One hundred years ago, heart disease was much less common in this country. Over the past century, though, heart disease has risen in tandem with our increasing intake of these seed fats, or omega-6s, according to the American Heart Association (AHA). So have neurological disorders like Lisa’s, as well as depression, arthritis, obesity, insulin resistance, and many cancers. While other dietary factors such as increased consumption of calories, trans fats, and sugar undoubtedly contributed, our essential fatty acid imbalance is a key player in most of these illnesses.
Over the same time period, omega-3s began disappearing from our food supply. Cows used to be raised on grass and other greens, producing meat, milk, and cheese with much higher concentrations of omega-3s. These were the animal products that our grandparents and great-grandparents grew up on, before industrial feedlots replaced family farms. Now these livestock are fed corn and soy, and their tissues are swamped with omega-6s. Chickens, too, used to eat grass and grass-eating bugs. Those chickens produced eggs and meat that were high in omega-3s, but now they’re fed full of omega-6-rich fall fats.
We are now eating a diet that is supposed to fatten us up for winter, when weather is harsh and calories are scarce. But today food is never scarce for the average American. The base of our food supply has shifted from leaves to seeds, and this simple change means our bodies are storing more fat, leading to obesity and all its associated diseases.
And in terms of how we got here, excellent as well.
A great deal happened to our food supply in those decades. Due to farm subsidies, the acres of soybeans, for example, grown in the United States exploded from about 4 million to 70 million. Oil processors like Archer Daniels Midland mastered the process of extracting oil from these and other seeds, and vegetable seed oils–thought to be healthy–began to dominate our food supply as they were added to the foods that make up the center aisles of the grocery store.
At the same time, food chemists discovered that rancidity in packaged foods was caused by the oxidation of some minor but pesky fats: omega-3s. Scientists extended the shelf life of processed foods such as cookies, chips, cakes, breads, and spreads by removing omega-3s–a nutrient that no one thought mattered. Health agencies, like the AHA, and the US government also promoted omega-6s, because seed oils are low in saturated fat and free of cholesterol. So omega-6 oils, such as corn and soybean, they thought, were good for the heart.
Scientists have known since the early 1970s, however, that omega-6s also promote blood clotting and inflammation, two immediate and direct causes of heart disease. But because omega-6s were essential, doctors thought you had to take the good with the bad. By the time they learned that omega-3s protect our hearts and fight inflammation, omega-6s were already the foundation of our modern food supply.
Well that’s already far more quoted material than I like, but oh well. The way it goes sometimes.
All is not complete joy, however. There’s a distinct underlying bias toward green leafy plant-based diets on the basis of alpha-linolenic acid (ALA – an omega-3) conversion to the forms of omega-3s that humans use, EPA and DHA, while only grudging acceptance that this conversion is "somewhat inefficient." Someone correct me if I’m wrong, but I believe the efficiency is on the order of about 3%. Hardly "somewhat."
The last two pages of the article provide some steps in how to increase omega-3 while decreasing omega-6. Not discussed in the article, however, is that the ratio of the two is probably as important, perhaps more important, than the absolute amount of omega-6. To give you some idea, a natural diet consumed by non-industrial peoples from equator to arctic circle will have a 6:3 ratio anywhere from about 4:1 to perhaps 1:2 for arctic Inuit. So, once again, evolution has afforded us a not-too-tight requirement. Plenty of leeway. But modern diets? I’ve read various claims, but they seem to come in somewhere at a 6:3 ratio anywhere from 15-30:1. Evolution simply didn’t provide for that at all.
As to increasing omega-3s, most of the advice is sound in that she talks about choosing grassfed meats and wild-caught fish. She asserts that "fish oil supplements [are] not a long-term solution to this widespread nutritional deficiency." Why? Unless you go live in a cave somewhere, you’re likely to be getting more n-6 than would be found in diets we evolved to eat. Restaurants, dinner with friends & family, the list goes on. And for many, the expense of grassfed meats and wild caught fish just isn’t an option. It is for these reasons that fish oil supplementation is probably the most important supplement and I can’t see any way around it being anything but a long-term solution. And it has the virtue of being pretty objective. You know precisely what amount of n-3 you’re getting. No guesswork.
The final page about lowering omega-6 intake, while not a disaster, is pretty much a mixed bag, in my book. I can’t believe someone that’s adept enough to research and write this article would tell you to replace a natural food, butter, with an industrially processed one — the solvent extracted oil from the rapeseed (canola).
But all in all, a very worthy read.
While I have not read Robert Andrew Brown’s book, Omega Six The Devil’s Fat, I can easily recommend it on the basis of his comment activity over at Stephan’s blog on so many entries over many months. I’m convinced he really knows what he’s talking about.
Finally, I recently reported on two amazing health improvements owing to fish oil supplementation. The first was the 95% drop in triglycerides Dr. Davis achieved in a few weeks. Then, Dr. Stephan reports on two fatty liver reversals here, and here.