"Meat is linked to cancer risk. When you cook meat, certain chemical compounds are produced that are linked to cancer, both breast cancer and colon cancer, and others."

"Sixty percent of the foods in a typical American diet are carbohydrate. If you take them out of the diet, you're on an old-fashioned, low-calorie diet. But that would also work if you took out all the foods from your diet that began with the letters A to G. You could arbitrarily knock out 60 percent of anything you ate and lose weight."

"You don't have to say 'For the rest of my life, I can't have another potato or bread.' Just be selective about which type of carb you choose. Then you can lose weight gradually, impressively, safely and in a more healthful way."

      Most people now realize that their food choices have a lot to do with whether they feel well or ill, energetic or sluggish, whether they are fat or thin. In other words, many people realize that food is potent medicine. But many people with whom we at Nexus speak are confused as to which foods, which diets, will produce the best results for them.

      Is "high quality protein" (translate meat) really important? But weren't the experts recommending we all eat lots of complex carbohydrates like whole grains while reducing our fatty meat consumption not long ago? The discussion rages on among those promoting "zone" diets and Atkins diets and blood type diets and vegetarian diets and many others. And in the background, scientists are writing up studies and the news media is summarizing them. Often the scientists contradict the pop-diet gurus. Who's right?

      We'll keep covering this story. (We love to print your views in our Letters column!) But this issue, we are delighted to interview Neal Barnard, MD, who has been an eloquent voice on the national stage for many years, including influencing federal dietary guidelines. As far as this discussion goes, he is in the vegetarian low-fat diet camp, along with John McDougall, MD, Dean Ornish, MD and John Robbins.

      Dr. Barnard is the president of the Physicians Committee for Responsible Medicine (PCRM), a nationwide group of physicians that promotes preventive medicine and ethical treatment of animals, especially in scientific research. PCRM also conducts research, including a breakthrough study showing that a new approach to diabetes can get many patients off their medication. Dr. Barnard is the author of five books, the most recent of which are Foods that Fight Pain (Harmony, 1998) and Turn Off the Fat Genes (Harmony, 2001). He is the editor of the PCRM newsletter, "Good Medicine." Nexus publisher and editor Ravi Dykema spoke with Dr. Barnard via phone.

 

RD:  Over the years, diet systems promising health, weight loss, energy or longevity come and go. But what does research tell us? 

 

NB:  The research that we have been doing-meaning the Physicians Committee for Responsible Medicine, along with Georgetown University Medical Center-shows clearly that the optimal diet is one that excludes animal products, keeps vegetable oils very low and uses foods in as natural a form as possible, with minimal processing. The closer we get to that sort of optimal diet, the better off we're going to be. Not only are we likely to be able to control our weight, but we're also going to be healthier in a great many ways, with a lower cancer risk, lower risk of heart disease, reverse heart disease that already exists and other health benefits.

 

RD:  A number of popular diets encourage low carbohydrate consumption and high protein consumption. Some of them even endorse a high fat and high protein diet. People I know who have tried this diet swear by it. What would you say to these people?

 

NB:  First of all, it's important to remember the epidemiology. When we compare different countries, the skinniest people on this planet are those living in rural Asia; Japan, China, Thailand and so forth. Happily they have never read those books saying that they should be phobic of carbohydrate. They eat astounding quantities of carbohydrate in the form of rice, noodles and vegetables, and relatively little meat. What meat or fish they do eat is usually a flavoring for the vegetables, and especially rice and other grains, that are their staples. They are the slimmest people on the planet until they move to Denver or Seattle or Portland or Los Angeles, and eat less rice and more cheese, meat and chicken. That's when they start gaining weight. So the idea that carbohydrates are the enemy, and that by avoiding them we're going to be slimmer and healthier, is a very myopic view. Now it is true that carbohydrates, for some people, can be problematic, but the answer is not to avoid them. The answer is to select the healthiest ones.

 

RD:  What are the "healthiest" carbohydrates?

 

NB:  First you have to understand what happens when you eat carbs. If you eat white bread, or any other starchy food, it starts to break apart in the process of digestion to individual sugar molecules that pass into the bloodstream. As the starch releases its sugars into the blood, insulin responds to take the sugar from the blood into the cells of the body. So with every bite of white bread, the sugar gets into the blood and insulin moves that sugar into the cells of the body. If you have already gained a fair amount of weight, or you eat a high-fat diet, you may become insulin resistant, meaning that the body needs more and more insulin to try to take those sugars out of the blood.

      The problem with this is that insulin has an additional job. It shuts down fat burning, so as long as it's present in the blood and busily storing sugar, it slows down our ability to burn fat. The Dr. Atkins approach, or other high-protein diets, say, "Let's just take all the carbohydrate out of the diet. Then insulin will not be released, and we won't shut down our fat burning." But Atkins made a major error. He forgot that insulin isn't just important for storing fat; it's also important for storing protein. And a slab of meat will cause a bigger insulin release than popcorn. So, biochemically, it's an erroneous approach. Even so, some people who follow this diet do lose weight-usually quickly, and for a short period of time. But eventually they get stuck, and find it's hard to maintain their lost weight. 

 

RD:  You mean they plateau short of their goal?

NB:  Yes. Or they gain it back, or they just can't stick to a diet. A diet that says you can never, ever have grains and many vegetables and so forth is very hard to stick to over a long period of time. And it's also unhealthy. A diet that excludes plant products is low in the fiber and antioxidants that we need to protect us from cancer and other serious illnesses.  

      Some of these diets do include fruits and vegetables. But the amount of meat or dairy products is way too high. Meat is linked to cancer risk. Cooking meat, especially at high temperatures as in broiling or grilling, causes the formation of heterocyclic amines which are potent carcinogens once they get into the body. These same chemicals are found in tobacco smoke and are 15 times more concentrated in grilled chicken than in grilled beef. A case in point: Suzanne Sommers, who has been promoting these diets, just revealed she has breast cancer herself. Was diet a contributor? We can't say for sure, but I think it should be a reminder to us that these are not low stakes we're playing for. But back to this question of why do people lose weight. Sixty percent of the foods in a typical American diet are carbohydrate. That's 60 percent of our nutrients. If you take them out of the diet, you're on an old-fashioned, low-calorie diet, and you're going to lose weight. But that would also work if you took out all the foods from your diet that began with the letters A to G. You could arbitrarily knock out 60 percent of anything you ate and lose weight.

 

RD:  Unless you replace it with something else as caloric.

 

NB:  Right. Now there's a much better approach. It's true that insulin is worth considering, and it's true that for some people who are insulin-resistant, they are going to do better if they choose a diet that doesn't cause a massive insulin response, because that disrupts fat burning. But the way to do it is not to avoid carbohydrate. The way to do it is to be selective. White bread does release its sugars quickly. Rye bread releases them more slowly.  Pumpernickel, slower still. If the white flour were turned into pasta, it's even slower, and al dente pasta, meaning not over-cooked pasta, releases its sugars even slower. And a slow release of sugars means less of an insulin response and less disruption of fat burning. If you take a big baking potato, it releases its sugars very quickly and causes a large insulin response. New potatoes release sugar slower, and sweet potatoes slower still.  So you don't have to say, "For the rest of my life, I can't have another potato or bread." Just be selective about which type you choose. Then you can lose weight gradually, impressively, safely and in a more healthful way.

      Let me be clear on one thing: carbohydrate isn't our enemy, and most people can completely ignore the whole carbohydrate issue. Most people lose weight simply by following a diet that avoids animal products, uses few fats and oils, and focuses on the new four food groups-vegetables, fruits, grains, legumes-and the foods that are produced by those groups, like pasta marinara, veggie chili, split pea soup or black beans in minestrone. When people do that, they lose weight. In our studies, virtually everyone loses weight with that kind of approach, even though they're not counting calories and they're eating lots of carbohydrates. The whole carbohydrate issue is an eccentric one for those people who have really difficult and unmanageable weight problems that persist, even though they're following a pretty healthy diet.

 

RD:  But if high-protein diets are so unhealthy, how have they gained such popularity?

 

ND:  If we sold books in Columbia saying that cocaine was a good thing, we'd probably be pretty popular. If you're in North America and you tell people that eating roast beef is a darn good idea, you'll be pretty popular. People love good news like that, even if it's poorly based. But let's be clear. In the research studies that we've done, we've used a much more healthful approach that is not carbo-phobic, and allows people to lose weight and get healthier. We also treat diabetic individuals and find that most of them get off their medications, or need a lot less, in a very short time by following a diet that avoids the animal products and is rich in whole grains, vegetables, fruits and legumes.

      I think the grain of truth in high protein diets is that certain foods, like certain grain products and starchy root vegetables, really do cause a rapid sugar release into the blood, and some people have to be concerned about that. That's as far as you need to go with that. When the solution is eat more meat, that's ludicrous. Meat is every bit as unhealthy as we thought it was. If it isn't hoof-and-mouth disease, mad cow disease, salmonella or E. coli, it's colon cancer and heart disease and so forth. It's just astounding the range of illnesses that people are willing to risk in following these absurd fad diets.

      A high meat diet is a short-term solution that compromises long-term health. One recent article found that people on the Atkins diet get worse over time. Their coronary arteries progress into aggressive atherosclerosis, meaning they're headed for a heart attack. And my conclusion has to be that you really cannot set aside the mountain of research showing that animal products are risky from a health standpoint, and try to embrace them just because of these fads.

 

RD:  What about those of us who eat mainly fruits, vegetables and grains, with meat once a week, fish and chicken a few times a week, and low-fat dairy products like yogurt? Can't this be just as healthy a diet as a no-animal-product diet?

 

NB:  The scientific data consistently point to a low-fat vegan diet as the best diet for reducing chronic disease risk. Dean Ornish has used a very-low-fat vegetarian diet to reverse heart disease. In a huge epidemiologic study done in China by Dr. Chen and Dr. Campbell over a 17-year period, they found that the closer the diet was to 100 percent plant foods, the lower the chronic disease risk. In our own studies, vegan diets show bigger improvements than low-fat diets that still include small amounts of meat, chicken, fish or dairy products in blood pressure, body weight, blood cholesterol levels and other markers of chronic disease risk. These lower-fat omnivorous diets are better than the typical U.S. eating pattern, but they clearly fall short of a low-fat diet built completely from foods from plant sources.

 

RD:  Back to carbs for a moment. So you think the best advice would be to eat in moderation the grains and root vegetables that cause a rapid release of insulin and are truly problematic for some people, and suggest that those people replace them with more appropriate high-carb sources?

 

NB:  If you're concerned about carbohydrates, that's about as far as you need to go with it. But once again, as I mentioned earlier, throughout Japan and much of Asia, a huge portion of the world's population eats these foods all the time. And their risk of obesity, diabetes or hypertension is very low. In our studies, people can consume carbohydrates to their heart's content, and they lose about a pound, pound and a half a week. And that doesn't sound like a lot over a week or two, but you add that up over 52 weeks, and that's substantial. And you haven't had to say no to a cookie, a potato or a piece of toast.

 

RD:  How do you get enough protein on a diet like that?

 

NB:  If you look at, well, there's protein in fruit, too, although not a lot, but there is protein in whole grains and beans and vegetables. Broccoli is 40 percent protein as a percentage of its calories. If you look at the massive musculature of a bull, or a stallion or an elephant, they have built their body from the proteins in the plant foods. A bull doesn't down some Spam, a slice of cheese and some weight-on mixture that he bought at the health food store. There is a huge amount of protein in plant foods, including all of the essential amino acids, which even without conscious combining are perfectly usable by the human body. And so long as a person is consuming any normal variety of vegetables, beans, grains and legumes, he or she will get adequate protein. It's not an issue. In fact, that's not only my position. That's been the position of the American Dietetic Association for many years, as well as that of the federal government.

 

RD:  Given that, is there a downside to increasing your protein substantially?

 

NB:  Yes. Protein depletes calcium. Osteoporosis is a condition in which bone calcium is lost into the bloodstream, and it filters through the kidneys and is lost in the urine. That pathway is accelerated by high protein intake, particularly animal proteins. Animal proteins are rich in what we call the sulfur-containing amino acids. These amino acids release sulfate into the blood, which tends to sweep the calcium through the kidneys. So a high-protein diet encourages bone loss. It also contacts the kidney, and cause the filter units of the kidney to wear out. 

      The biggest problem, though, is that people forget there's no protein aisle at the grocery store. When people say protein, they often mean meat, which is not just protein. It's a mixture of protein and fat, along with the occasional parasite or salmonella or something. Along with the protein, you get saturated fat that causes heart disease and you get carcinogens. Also, the animal fats are the repository of most of the environmental pollutants that make their way into the human diet. 

 

RD:  So you're getting some negatives with the protein, and the positives might not even be worth it. 

 

NB:  I don't think there are any positives in increasing protein beyond the body's basic needs. The only reason to increase protein would be if you're eating a lot of sugar in your diet. You would feel tired and depleted. Protein-rich vegetarian foods like beans, chick peas and so forth can counteract that affect to a degree, and the earlier in the day you have them, the better off you're going to be. But a better solution is to eliminate the sugar from your diet.

 

RD:  I know a number of people who were vegetarian who've switched to being meat eaters partly under that influence.

 

NB:  Ravi, you're hanging around with the wrong people. A lot of people have naively followed this high protein diet, but it's certainly not everybody, and frankly, I think its time has passed. 

      It's a terrible diet. Many people just can't tolerate it. Some people like it because they like a cut of meat, but over the long run, their health is abysmal and they will not achieve their weight loss goals with it. My only hope is that they will understand how to prepare vegetables, fruits, grains and legumes the right way so that they can enjoy the taste, and be slim and healthy at the same time. Anybody who's done an Atkins diet and was impressed with their results would be absolutely blown away by what you can do with a well-prepared, low-fat vegan diet. I will have patients occasionally ask, "Is this weight loss ever going to taper off?" They're doing so well burning off the pounds. Everybody's different, but the diet we recommend just knocks the socks off of something like an Atkins diet.

 

RD:  Are other writers or speakers promoting a similar sort of diet?

 

NB:  Yes, and the entire credible scientific community is on the same side I am. People like Dean Ornish, John McDougall and the Loveland Clinic promote plant-based, vegetarian or vegan diets. There was a commentary the other day by Robert Eckel, who is with the Nutrition Committee of the American Heart Association, blasting Atkins and pointing out that the Atkins diet is an abysmal diet.

 

RD:  What about the state of the meat industry now? Some people fear that because of hoof and mouth and other diseases, we might lose our meat industry altogether.

 

NB:  I certainly hope we do. It would be a great boon to the American consumer to have the meat industry be gone. It would be a tragedy for the American cattle rancher. The folks involved in the cattle industry are good and decent people. And, like the tobacco industry before them, they got into a business before its health risks were fully understood, and before the tragedies of mad cow disease, hoof and mouth disease, E. coli and the product recalls that seem to happen about every other day. It is a tragedy for the people who get sick and for the people who make their livelihoods from raising meat.

      What I recommend is not punishing the farmer, but also not supporting these businesses. Let's face it, if you get a heart attack from eating beef, it's a tragedy. There's no reason to be baling out these industries. What we should do is to help the people whose lives are connected with meat production, help them to transition into something more healthful, as we've been exploring with the tobacco growers. We should be doing the same with the meat and dairy industries.

 

RD:  How do you think that would come about?

 

NB:  In the case of the tobacco industry, the government has looked at what can you raise on that land, what other kinds of jobs are needed in those geographic areas and so forth. With the cattle industry, we could do much the same. The industry is changing so dramatically anyway, and quite often the younger generation doesn't follow in parents' footsteps into the business. They're looking for other things to do. But trying to bail it out and support it, and to support beef prices or dairy prices by buying these products up and serving them in schools is to condemn another generation to the same problems that we're seeing now, which is a population that is more out of shape than it has ever been, enormous rates of disease, people in long lines at the prescription counter for cholesterol lowering drugs and diabetic drugs and anti-hypertensive drugs, things that in 90 percent of cases you would never need if people were on a healthy, low-fat, vegan diet.

 

RD:  It doesn't look like that's changing-consumers still go for fast-food hamburgers and other meat products.

 

NB:  Some of them do, but not all of them. Look at what's going on in the health food industry. Twenty years ago, you'd go into a health food store and it was a small, dark place with dusty shelves and a person behind the counter named Sunshine with a tie-died shirt. Nowadays, you go into health food stores and they're huge. They have great products and an enormous variety, and there's huge demand for them. Somebody is buying those things. So the entire world is not lined-up at McDonald's. There are plenty of people voting with their fork for a much more healthful set of choices.

      The government and scientific community could endorse a plant-based diet, even on a one-on-one level, but haven't seemed to. For example, you'd think a responsible family practice physician would tell his or her patients that they were courting disease if they ate a diet based on meat, and that they should head in this other direction. I'm sure there are some who do say that, but I know the majority of them don't.

 

RD:  Isn't that a front that could change? Don't you think that if the research was even more convincing, that medicine itself would be promoting over and over again this change?

 

NB:  We now have a great many doctors in the Physicians Committee for Responsible Medicine who promote healthful diets, whereas 20 years ago, we did not see that. The U.S. government now says that most of our nutrition should be coming from plant sources. The pyramid that came out 10 years ago was the government's first attempt to say this, that whole grains, vegetables and fruits were the basis of a diet, and that meats and dairy products were less emphasized. Now, the government's own pronouncements have gone progressively more and more in that direction.

      The American Cancer Society, about two or three years ago, pointed out that meat does contribute to cancer. The National Academy of Sciences has been pointing this out since at least 1982. So the government and the contracting quasi-governmental organizations, like the National Academy of Sciences and the National Research Council, have been pointing this out, and the evidence is certainly clear enough. The difficulty is that certain laws mandate that the USDA promote certain agricultural products, like meat and dairy products. Every milk mustache ad you ever saw is actually produced by a program administered by the U.S. government, including those that encourage full-fat, artery clogging milk products. So the government is in a bit of a pickle that results in the fact that it has very mixed mandates. The force of industry is enormous, of course, and the force of our habit is a problem as well. But people can change their diets, and I'm very optimistic about that because we see it every day. 

      I often talk to people who have read my books-Turn Off the Fat Genes, which appeals to people who have weight problems, or Foods that Fight Pain, which was for people with migraines, arthritis, back pain, menstrual cramps or any other painful conditions. One after another describes that when they understand how foods really work within their bodies, their lives just aren't the same anymore. They have power that they didn't have before. And that, for me, is very gratifying to see, because it's not just one or two people. This happens by the thousands. It's true that many members of the press and government and in the medical community are confused about what constitutes a healthy diet, but the science of it is compelling enough for people to take action.

 

RD:  It sounds like your view of this is fairly centrist, that it's not a fringe idea.

 

NB:  What's centrist is that the diet should be primarily plant based. There is disagreement as to whether or not it should be vegetarian or vegan. Some people would say I'm going too far by recommending the diet should be derived exclusively from plants. There are some people who say that I don't go far enough, that it should not be just entirely plant, but it should be raw, or macrobiotic, or whatever. So a low-fat vegan diet is really simple actually. And it's also a centrist idea that the Atkins diet is a big mistake.