Kilmer McCully has indeed led a revolution because his work . . . has provided powerful evidence that nutritional deficiencies are an important cause of heart disease. Not surprisingly, this notion encountered great resistance . . . This is also the story of a personal struggle by a brilliant physician against a powerful and rigid scientific establishment.
- Dr. Walter Willett, Harvard School of Public Health.
IN 1968, KILMER MCCULLY was a young pathologist studying inherited diseases at Ma.s.sachusetts General Hospital in Boston. One day, pediatricians told McCully about an eight-year-old boy who had died of a stroke at the same hospital in 1933. The case was unusual enough to be written up in the New England Journal of Medicine, and it made McCully curious. When he tracked down the original autopsy slides, he saw the severe arteriosclerosis diagnosed by the pathologist on the boy"s death thirty-five years before.
The boy had a rare genetic disease called h.o.m.ocystinuria, which is caused by faulty B vitamin metabolism and named for h.o.m.ocysteine, an amino acid that appears in the urine. Other symptoms include long limbs, mild mental r.e.t.a.r.dation, and severe arteriosclerosis. Children with h.o.m.ocystinuria die of conditions one a.s.sociates with old age: blood clots, heart attack, stroke. There is no cure, but high doses of vitamin B6 help relieve symptoms in about half of patients.
McCully happened to be familiar with h.o.m.ocysteine and cholesterol metabolism.39 In 1968, the leading theory of arteriosclerosis was that cholesterol attacked the arteries. But McCully didn"t believe cholesterol caused the damage he saw in this case. If cholesterol caused arteriosclerosis, why was there no cholesterol in this boy"s arteries? Mulling it over, McCully recalled animal studies linking deficiency of B vitamins and folk acid to arteriosclerosis, and he reflected on the cause of h.o.m.ocystinuria: faulty B vitamin metabolism. After many sleepless nights, his eureka moment came: McCully realized that excess h.o.m.ocysteine due to lack of B vitamins and folic acid caused arteriosclerosis. Cholesterol did not.
In 1969, McCully described his hypothesis about arteriosclerosis in the American Journal of Pathology and proposed a simple treatment: folic acid and B vitamins to keep h.o.m.ocysteine down. At first, this alternative theory of arteriosclerosis was big news, and scientists all over the world asked for copies of the article. In 1970, the hospital praised his work as an example of "the unpredictable, important contributions which can come when an imaginative, skilled worker is given free reign to follow his findings."
But the warm reception was brief. The cholesterol hypothesis was still the establishment view; in 1968, experts had decreed that 300 milligrams of dietary cholesterol daily was the "safe" upper limit. As news spread of this apparent threat to the cholesterol theory, the medical world shunned McCully. He lost his research funding and his posts at Harvard and Ma.s.sachusetts General Hospital. He went jobless for two years.
Now, more than thirty-five years later, McCully is the chief of pathology at the Veterans Affairs Medical Center in Boston, and he treats the affair as a backhanded compliment. "If what I had discovered was unimportant, no one would have cared," McCully told me brightly.40 He can afford to be magnanimous, because today the role of h.o.m.ocysteine is widely accepted. The landmark Physicians" Health Study on diet and heart disease found that male doctors with high h.o.m.ocysteine were three times more likely to have a heart attack than those with normal levels. In the large and prestigious Nurses" Health Study, women who ate the least folic acid and vitamin B6 had the highest heart-related death rates. The famous Framingham Heart Study also linked h.o.m.ocysteine to heart disease. McCully"s rehabilitation is complete. He is known as the "father of h.o.m.ocysteine."
About twenty human trials examining h.o.m.ocysteine are under way all over the world. McCully is supervising the h.o.m.ocysteine Study, a national clinical trial of two thousand veterans sponsored by the U.S. Department of Veterans Affairs, in which people with kidney failure- a risk factor for heart disease- are taking a placebo or large doses of folic acid and vitamins B6 and B12.
B VITAMINS AND FOLIC ACID IN THE h.o.m.oCYSTEINE STUDY.
Note the large vitamin doses in the h.o.m.ocysteine Study (HOST). Folic acid and B vitamins are perfectly safe.
RDA* Ideal RDA Dady dose in HOST.
* Recommended Daily Allowance (RDA).
According to Kilmer McCully, The Heart Revolution.
The normal role of h.o.m.ocysteine is to control growth and support tissue formation, but in excess, it damages the cells of arterial walls, destroys the elasticity of the artery, and contributes to calcification of plaques. Vitamins help by reducing h.o.m.ocysteine. Folic acid and vitamin B12 convert it to harmless methionine, and vitamin B6 converts it to cysteine, which is excreted. Less well known nutrients betaine and choline also reduce h.o.m.ocysteine.
The actions of h.o.m.ocysteine fit with what we know about heart disease. It raises triglycerides and forms oxidized LDL, which causes arteriosclerosis.41 h.o.m.ocysteine travels on LDL, which explains the high LDL seen in some people with heart disease. In addition to diet, many other factors- old age, menopause, smoking, diabetes, lack of exercise, being male, high blood pressure- raise h.o.m.ocysteine, and every one is linked to heart disease. "All along, it was h.o.m.ocysteine causing the damage," writes McCully, "while cholesterol was getting the blame."
A popular parlor game in cholesterol circles is solving the mystery known as the French Paradox. Why do the French have low rates of heart disease despite relatively high blood cholesterol and a diet rich in saturated fats? The French Paradox is only paradoxical if you believe that natural saturated fats cause heart disease, of course. But let"s pretend they do for the moment. Perhaps red wine is the answer, or smaller portions.
McCully believes the key to the mystery is the pate, sauteed calves" liver, and sweetbreads the French are so fond of. Liver and organ meats are superlative sources of folic acid and B vitamins, which keep h.o.m.ocysteine levels low. h.o.m.ocysteine also explains why people from Papua New Guinea to Nigeria can eat liberal amounts of saturated fat and yet escape heart disease- another paradox for the conventional wisdom. Traditional diets are low in white flour and sugar (which deplete B vitamins) and rich in meat, liver, fish, whole grains, and green vegetables, all of which are good sources of folic acid and B vitamins.
WHAT TO EAT TO KEEP h.o.m.oCYSTEINE LOW.
Folic acid, vitamins B. and B10, betaine, and choline reduce h.o.m.ocysteine. Note that B12 is found only in animal foods.
To keep h.o.m.ocysteine levels healthy, eat beef, liver, oysters, eggs, whole grains, and green vegetables. Remember that vitamin B12 is found only in animal foods, especially salmon, tuna, cheese, eggs, liver, beef, and lamb. Also, nutrients are lost when food is processed.
About 80 percent of folic acid disappears when whole wheat flour is milled into white flour, and vitamin B6 is easily damaged by heat. Thus canned tuna contains half as much B6 as fresh tuna. Vitamin B12 is more robust to heat, but microwaves damage nutrients much more than conventional heat.
McCully was not the first to blame industrial foods for heart disease, but his discovery about h.o.m.ocysteine was a giant leap forward in our understanding of how, exactly, refined foods damage the arteries. "The first case of heart disease as it is known today was reported in 1912, the second in 1919, and since then it has developed into a major killer," wrote Adelle Davis in Let"s Get Well. "The obvious change has been the ever-increasing consumption of refined foods and hydrogenated fats. The populations of the world living today on unrefined foods, in which nature packages with her fats all the nutrients needed to utilize them, do not develop heart disease." She was writing in 1965. More than forty years later, Adelle Davis"s books are still worth reading. Even more remarkable, her work is cutting edge.
BEYOND CHOLESTEROL.
What Causes Heart Disease * Deficiency of any of the following: omega-3 fats; folic acid, vitamins B6 and B12; antioxidants, including CoQ10 and vitamins C and E * Excess omega-6 fats (polyunsaturated vegetable oils).
* Inflammation (from infection and excess corn oil).
* Oxidized cholesterol (from free radicals in the body and powdered eggs and milk).
* Sugar.
* Trans fats (hydrogenated oils).
A Few Risk Factors.
* Age (84 percent of people who die of heart disease are sixty-five or older).
* Excess weight, particularly belly fat.
* Sedentary lifestyle.
* Diabetes (also metabolic syndrome, or prediabetes).
* Family history of heart disease.
* High blood pressure.
* High C-Reactive Protein (an indication of inflammation).
* Kidney and gum disease.
* Menopause.
* Smoking.
* Thyroid disease.
* High blood sugar.
10.
The Omnivore"s Dilemma.
IN THE EARLY 19 70S, my father"s parents came to visit us in Buffalo, New York, en route to Yugoslavia. Then, as now, we ate simple food, always made from scratch: some protein, whole grains, vegetables, a green salad. Sugar was a treat. As they left, my grandfather said cheerfully, "Let"s hope there"s dessert in Yugoslavia!"
It is said that every household resembles a small nation-state. If so, each family has its Department of Health and its food and cooking policies. In our house, my mother (like most mothers) wrote the law. Like most daughters, I left home, founded a new colony of sorts, and wrote my own (vegan and vegetarian) laws. When that turned out badly, I was happy to come home to the foods I"d grown up eating, but I also wanted to know what science had to say about them. Now I am satisfied that b.u.t.ter and eggs are good for you.
It is not easy to decide what to eat. There are virtually no limits today. We are not like foragers, who found a beehive dripping with honey only now and then; we are not like the babies in the Clara Davis experiments, who could choose only from nutritious foods. And things move fast. In the modern food industry, novelty and technical wizardry are the rule. In the United States, ten thousand new processed foods come on the market each year, and it seems a new diet is always climbing the bestseller list. Unlike industrial food, real food is fundamentally conservative. It is the food you already know: roast chicken, tomato salad with olive oil, creamed spinach, sourdough bread, peach ice cream. To me, that"s a relief. When you rule out industrial foods altogether, it does simplify things a bit.
The quest for the right diet is not a modern conundrum. It is not merely the result of unprecedented variety and abundance or even of the profusion of contradictory nutritional advice. On the contrary, our search for the right food is as old as eating itself. Since prehistoric times, every human has asked: what"s for dinner?
Culture undoubtedly plays a role in how we decide what to eat. Hindus don"t eat cows, for example. But culture is a minor determinant compared with nutritional needs, which traditionally trump all other factors. What will nourish the body for a day"s labor, through a long winter, or to recover from an infection? Survival alone is not enough. For men as well as women, food must also be adequate to ensure fertility. For most creatures, nutrition is simple: instinct rules. Insect or mammal, herbivore or carnivore, the menu is typically short. Parsnip worms eat parsnip seeds, ladybugs eat aphids, koala bears eat eucalyptus leaves, zebras eat gra.s.s, and lions eat zebras. But we are omnivores. We can and will eat anything.
Omnivores are highly adaptable and humans especially so. That"s why we occupy not one ecological niche but many, from frozen tundra to moist forest to scorched desert. This is a singular achievement; no other species lives in all the major habitats. A penchant for trying new foods in new situations was key to the success of all the h.o.m.o tribes, including ours. "When the eucalyptus trees all die in a given place, so do all the koalas," writes Richard Manning, "but omnivores have options."
Along with these options comes a unique problem, namely, that not everything that looks like food is edible and some things might be poisonous. In 1976, the psychologist Paul Rozin called this the omnivore"s dilemma. One eucalyptus tree meets all the nutritional needs of a hungry koala, but an omnivore must successfully balance curiosity and caution to survive. Various tactics come in handy. As social animals, we pa.s.s the word along that this berry or that insect is to be eaten or avoided. Contemporary hunter-gatherers without formal education in botany or zoology can identify hundreds of plant and animal species and many details about their medicinal or toxic properties, life cycles, habitat, and habits. The Harvard psychologist Steven Pinker calls this intuitive biology, and it is surely the product of the omnivore"s quandary. Omnivores also avoid things that smell rotten, and only nibble at unfamiliar foods. Researchers describe another tactic as the "poisoned partner effect." If a rat smelling of a particular food is looking poorly, other rats will avoid that food.
Even so, omnivores do get things wrong, especially in new situations, and suffer for it. When Americans settled west of the Appalachians in the 1800s, people began to get "milk sickness," which caused weakness, nausea, thirst, foul breath, and finally, death. In certain Indiana and Ohio counties, the illness was rampant. It was noticeable that where people were dying, cattle with similar symptoms got the "trembles." The twin epidemics aroused the curiosity of an Illinois midwife, Anna Pierce, who asked a local Shawnee woman for advice. The woman led her directly to white snakeroot, a plant that caused the trembles in cows and poisoned the milk. The active compound of snakeroot- tremetol- was not identified until 1928. One doctor who doubted that Pierce had found the cause of milk sickness ate snakeroot to prove her wrong; he promptly died.
In modern life, the risk of unintentional poisoning is greatly reduced. We don"t have to guess which foods might make us sick because the food supply is no longer wild. Botany is now a formal body of knowledge, scientifically tested. My parents taught me that rhubarb leaves contain toxic oxalic acid, while the stems make great pie; they learned that from books, not at the knee of the local wise woman. But the modern omnivore is not out of the woods yet. The risk of nutritional imbalance is great. Rozin writes: "A koala that eats only eucalyptus leaves has no such risk; it is adapted to survive on the nutrients eucalyptus has to offer. Similarly, a lion rarely risks imbalance, because the zebras it eats already contain the range of nutrients it needs. But the generalist happens upon many potential foods that have nutritive value, but are not complete nutrients. Appropriate combinations of foods must be selected."
There"s the rub. Unlike lions and other specialists, we have to think about which foods are nourishing, and in this respect, life is more confusing than ever. Modern humans face a vast choice of food, far beyond what was ever available before in both variety and quant.i.ty. Although traditional diets vary widely, in any given place, humans always ate a limited menu of local, seasonal foods.
Together, technology and migration have produced an unprecedented profusion of food. Freezing, canning, pasteurization, and other technologies extend the shelf life of perishable foods. Global trade has expanded variety beyond the imagination of any hunter-gatherer. The coffee, tea, spice, and olive oil trades are thousands of years old, but even this ancient commerce is recent in evolutionary time. The scale of modern trade is astounding. When there is snow on the ground, we can eat sweet corn and tomatoes; in cold climates, mangos and pineapples are easy to come by; in most American towns, Italian olive oil, Chilean grapes, and Thai shrimp are not luxuries but staples. Perhaps the most profound contribution of technology is the creation of truly new foods such as canola oil and margarine.
As exotic foods have circled the globe, so have people. Migration has loosened, if not severed, the bonds between people and their traditional foods. For most of human history, a child ate what her parents ate: yogurt in Turkey, miso soup in j.a.pan, cheese in the Swiss Alps. Today, the foods of every culture, from hummus to tortillas, mingle in restaurants, shops, and markets. The United States, a land of immigrants, is particularly diverse- and apt to slough off tradition- but something similar occurs in most wealthy nations: the typical diet is not the traditional one. The modern omnivore"s dilemma is acute.
THE OMNIVORE"S FEAST- WHAT"S FOR DINNER?
* Eat generous amounts of fresh fruits and vegetables daily.
* Eat wild fish and seafood often.
* Eat meat, game, poultry, and eggs from wild, pastured, and gra.s.s-fed animals often.
* Eat full-fat dairy foods, ideally raw and unh.o.m.ogenized from gra.s.s-fed cows, often.
* Eat only traditional fats, including b.u.t.ter, lard, poultry fat, coconut oil, and olive oil.
* Eat whole grains and legumes.
* Eat cultured and fermented foods such as yogurt, sauerkraut, miso, and sourdough bread.
* Eat unrefined sweeteners such as raw honey, evaporated cane juice, and pure maple syrup in moderation.
For three million years, we were skilled fishermen and hunters, able to kill giant animals such as wooly mammoths and fast ones such as wild horses, not to mention lions, sloths, bears, moose, giant lemurs, and camels. We hunted with a powerful combination of tools unique in the animal world: sharp spears, binocular vision, hand-eye coordination, and teamwork. We filled up on fish and game when we could, and in between we made do with every berry, tuber, and insect we could find. This dietary strategy- mostly predator, part forager- was simple and effective.
Then, in the blink of an evolutionary eye, something catastrophic happened. About thirty-five thousand years ago, the megafauna (big game) dwindled and then disappeared. "They became extinct in every habitat without exception," writes the historian Jared Diamond, "from deserts to cold rain forest and tropical rain forest." We humans were the main predator of these wild animals, which had thrived for tens of millions of years before we arrived. Until recently the suggestion that we killed them off- the "overkill hypothesis"- was ridiculed. Now most scientists agree that the big game were not doomed by an ice age or drought, but by spears and clubs.
Having depleted our chief source of nutrition, we did what only omnivores can do. We went looking for other foods to eat. We hunted less big game and began, gradually, to domesticate smaller wild animals for meat and milk. We foraged more and began to nurture wild crops like yams. The result was amazing variety in our diet. When an Iron Age man slipped into a peat bog in Denmark twenty-two hundred years ago, his stomach held the remains of sixty species of plants. Our brains are wired and our bodies are built to hunt and gather. Hunger is our motivation, variety is the result, and health is our reward.
Perhaps this explains my urge to forage. At the farm, I enjoy nothing more than picking vegetables for dinner, finding nettles behind the barn, or cutting watercress from the footbridge over the creek. Browsing the farmers" market always makes me happy. Even rummaging in the fridge in search of inspiration for dinner is a little adventure.
Variety is the hallmark of the human diet and its greatest pleasure. At my house, there may be a dozen different foods- from beef to bacon, olive oil to b.u.t.ter, kohlrabi to zucchini- at just one meal. I am not ambitious enough to put sixty vegetables, much less sixty species, on the dinner table, but when I am shopping for food or cooking dinner, I try to remember the rich array of life in the last supper of the Iron Age man, and I feel lucky to be an omnivore, blessed with a thousand ways to eat well and be well.
Where to Find Real Food.
For Nina"s current shopping list, see www.ninaplanck.com.
Local Foods.
Local food is sold in all kinds of venues. These two national sites cover all the options, from farmers" markets to farm stands and farm shares.
www.foodroutes.org.
www.localharvest.org.
American Farmers" Markets.
Find your local farmers" market. The USDA keeps a reasonably comprehensive list of farmers" markets in the United States.
www.ams.usda.gov/farmersmarkets.
British Farmers" Markets.
In London: www.lfm.org.uk.
FARMA lists farmers" markets in the United Kingdom.
www.farma.org.uk.
American Farm Shares or Community-Supported Agriculture Buy a farm share and get a weekly delivery of local foods all season. Most farm shares include produce and flowers; some add meat, dairy, poultry, and eggs.
www.nal.usda.gov/afsic/csa.
Gra.s.s-Fed and Pastured Meat, Dairy, Poultry, Eggs, and Game.
Jo Robinson, author of Pasture Perfect, provides excellent information on the benefits of gra.s.s-fed meat, dairy, eggs, poultry, and game, and posts an extensive directory of foods.
www.eatwild.com Niman Ranch is a network of several hundred independent farmers and ranchers who raise traditional beef, lamb, and pork. Look for lardo, ham, bacon, and other cured meats without nitrites.
www.nimanranch.com or 510-808-0340 In Virginia, Buffalo Hunter Meats sells American bison, gra.s.s-fed beef, pastured pork and poultry, and rabbit. Try the jerky and bacon.
www.buffalohuntermeats.com or 540-727-8590 The American Pastured Poultry Producers a.s.sociation lists farmers who raise pastured poultry.
www.apppa.org The Campaign for Real Milk describes raw milk laws in each state and will lead you to buying clubs and cow shares for raw milk, b.u.t.ter, cream, yogurt, and cheese.
www.realmilk.com Organic Pastures Dairy sells organic, gra.s.s-fed raw milk, cheese, and b.u.t.ter in California. It ships raw dairy foods frozen, exclusively for feeding pets (nod, wink).
www.organicpastures.com or 877-729-6455 Wild and Farmed Fish and Seafood All Alaskan salmon is wild. Because the state banned fish farming, wild salmon and other fish are abundant in Alaska"s clean, icy waters. The best fish is "frozen at sea" and vacuum packed. The following fishing boats, fishing co-ops, and purveyors sell wild salmon, halibut, sablefish, tuna, and other seafood from the Pacific Northwest.
Cape Cleare Fishery, www.capecleare.com or 360-385-7486 Dungeness Seaworks, www.freshfrozenfish.com Dungeness Seaworks, www.freshfrozenfish.com Marbled Chinook Salmon, www.marbledsalmon.com Prime Select Seafood, www.pssifish.com or 888-870-7292 Vital Choice, www.vitalchoice.com or 800-608-4825 Vital Choice, www.vitalchoice.com or 800-608-4825 Troll-caught Albacore Tuna, www.albatuna.com Fish Oil The nanny was right. Cod liver oil is the most valuable fish oil supplement because it contains vitamins A and D along with omega3 fats. All cod liver oil is refined to some degree, which reduces vitamins. Most manufacturers add synthetic vitamins back. According to an article by David Wetzel in the Fall 2005 issue of Wise Traditions, the brands listed below use only natural vitamin A and D. Some are flavored with mint, cinnamon, or citrus. (Nannies served cod liver oil in orange juice, another good method.) If you don"t care for cod liver oil, try wild salmon oil capsules from Vital Choice.