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interview: james kenney
If people want to eat low fat, they should eat a diet full of fruits, vegetables, whole grains, and beans, not full of fat-free cookies, cakes, and chips.

Doctor, for a layperson like me, what's the basic thing to know about Pritikin? What is it? What's the diet?

Well, the Pritikin diet is basically a healthy diet. I mean, Pritikin didn't start as a weight loss program. It started as a way to reverse heart disease, high blood pressure, diabetes. And weight loss is really a side effect of eating a healthy diet. And what we have people eat is mostly a lot of fruits, vegetables, whole grains, beans, a little bit of seafood, some nonfat dairy products or some soy milk.

No meat, no fish, no chicken?

They can eat fish and seafood and poultry and very lean meat in modest amounts. That's the only thing we really limit on the diet. We don't restrict calories. People can eat as much as they want on this diet and still lose weight, mainly because people feel fuller when they eat this type of food than when they eat the junk food that makes up most of the American diet.

James Kenney is the chief nutritionist at the Pritikin Longevity Center, which espouses a low-fat diet in combination with exercise to reverse chronic disease, including heart disease, diabetes and high blood pressure. In this interview, he explains the basics of the Pritikin program and how low-fat diets allow people to achieve satiety on fewer calories. Kenney tells FRONTLINE that Pritikin considers weight loss to be a side effect of a healthy diet and exercise program. "But it's still a matter of discipline," he says. "You have to take responsibility for your health." This interview was conducted on Jan. 6, 2004.

What fills them up?

People fill up on vegetables, potatoes, whole-grain pastas, brown rice, fruits. These are very filling foods. Research has shown that when people eat these types of foods, that they feel satisfied on far fewer calories than when they eat croissants when they eat steaks, when they eat eggs, those types of foods.

So basically this is a low fat diet?

Yes. It's low in fat, particularly saturated fat and hydrogenated fat, because those are the fats that really push up cholesterol in the blood and lead to clogged arteries, the number-one killer of most Americans.

And where do those come from? What foods are the culprits?

Most saturated fat comes from meats and cheeses and dairy products. And most of your hydrogenated fats are found in things like cookies and potato chips and Pringles and that type of stuff. …

And drinks. There's been a lot of talk lately about super-sizing drinks. But Coke, Pepsi, soft drinks?

Yes. Very bad diet. If you want to lose weight, you don't want to be drinking a lot of calories, and particularly sugar and water. We've known for years that if you want to fatten up rats, you can fatten them up a lot quicker with sugar water than with just plain sugar. …

Because it delivers it faster?

Yes. It gets into the body quicker, and somehow it doesn't register as much satiety, fullness basically. …

But on Pritikin, what about fruit juices?

Well, we actually discourage the use of fruit juice. We don't eliminate it completely, but here's the facts: Research has shown that oranges are far more filling and satisfying, on the same number of calories, as orange juice. You could eat three or four oranges in the morning. You probably wouldn't be able to eat your regular breakfast. But if you drink a glass of orange juice with three or four oranges squeezed, you'll eat that whole breakfast. And the truth is, the only way you lose weight is to eat fewer calories. The key is to eat fewer calories but not be hungry. That's why we advocate whole fruit and not fruit juices most of the time. …

The other thing that people worry about a lot, about diets, is that you're not satisfied. Doesn't fill you up. And if that doesn't happen, then it's very, very hard to stick to. So Pritikin is kind of hard to stick to, isn't it, because it's very low-fat?

Well, you know, no diet is easy because it makes people change their bad food habits. But the truth is, the Pritikin program is much easier to stick with long term, because we're not requiring you to go hungry. We're having you eat food that makes you feel fuller and more satisfied on fewer calories. The result is you can eat fewer calories and not be hungry. If a diet is requiring you to eat fewer calories of the same low-satiety foods that don't make you feel satisfied, then you have to go to bed hungry every day for the rest of your life in order to keep the weight off. Well, not many people are going to do that, which is why most diets fail. …

So it's a little embarrassing, but let me start on a personal note here. I'm 54 -- be 55 next month, by the time this documentary airs -- and I'm 5'11", and I weigh between 205-210, about 210 now. I've definitely put on weight [over] the last 10 years. When I played high school or college sports, I was 155-165, probably 180 in my 30s. So I've put on weight, definitely. How serious a problem is that? Should I be concerned about it?

Oh, sure. I mean, there's unequivocal data that the heavier you get for your height, the higher your BMI goes, the greater your risk of dying from cardiovascular disease, cancer, particular diabetes goes way up. So weight is a big issue from a health perspective. Many Americans worry about weight in terms of their appearance, but health is probably the bigger issue, particularly as you get older.

How tall are you?

I'm 6'3" and I weigh the same now as I did when I graduated high school.

That's incredible. And honestly, how do you do that?

I eat healthy and I exercise.

How important is exercise? Because you read some of these diets and it's like: You don't have to exercise. Just take this pill. Or do what we tell you and eat this.

You always know you're dealing with a fad diet when they tell you, you don't need to exercise, that you can eat as much as you want of foods that seemingly are really fattening or bad for you.

Exercise is extremely important. We know that when you go from sedentary to active -- and when I say "active," I'm talking about walking three, four, maybe five miles a day -- that you're not likely to increase your food intake, so what you're doing is creating a nice calorie deficit without hunger. And that's why, when you look at long-term success in terms of weight control, most research suggests that most people who are successful exercise and change what they eat. …

Why did you get into this? What spurred you to become so interested with nutrition and eventually end up working for Pritikin?

Well, I got my Ph.D. in nutrition from Rutgers back in the early '70s. But back then, I was more concerned with gaining weight. And in fact, sadly, I was successful. I went from about 157, where I am now, up to 197. And now I'm back down to 157. So you can put on a lot of weight in college, if you're eating the cheeseburgers and all the other bad food.

I was studying nutrition because I was concerned really about athletic performance, back then. And when I was in my early 30s, I had high blood pressure, a cholesterol over 300, and was starting to put a little bit around the waist. That inspired me to start changing my diet, putting the information that was up here into practice for myself.

Now, Pritikin, as I understand it, really grew out of an attempt to deal with heart disease, with patients who had heart problems.

Yes. Originally, the diet was devised to stop or reverse heart disease, which is still the number one killer of Americans. But one of the side effects we noticed with people on this diet is, not only did their cholesterols go down and their angina or chest pain go away, but a lot of times they would lose weight, their diabetes would go away, their blood pressure would normalize.

And over the years, we've published 70-80 studies or more in peer-reviewed journals, showing that in fact our diet does what we claim it does, in terms of reducing all of the degenerative diseases that plague most Americans. And a side effect, as far as we're concerned, of a healthy diet and exercise program, is normalizing your body weight. And health is our top objective, not losing a lot of weight as quickly as possible.

Let me ask you about that, because some of the critics of Pritikin will say, "Okay, this is terrific for people who have heart disease, but this is not a very good way for the general public to lose weight because it's too tough. You can't stick to it."

Well, it's not that difficult to eat healthy and exercise if you're buying the food yourself and eating it at home. What makes eating healthy in America difficult is that most restaurant food, particularly fast food restaurant food, is designed to make people fat and sick. And if you go into a fast food restaurant and look for something healthy to eat, it's kind of a challenge. So I will agree that there's some difficulty in eating healthy in an environment which basically encourages people to eat unhealthy, and provides people with all these energy-saving devices so they don't have to do any physical work.

But it's still really a matter of discipline. You have to take responsibility for your health. If you want to be healthy, if you don't want these diseases, if you want to lose weight, you're going to have to change your eating habits, you're going to have to exercise more than most people feel like. But the nice thing about it is, the more you do it, the easier it gets and the better you feel. And as a side effect, you don't have to worry so much about heart disease, cancer, and diabetes.

Let me ask you about the Atkins diet, because when I walk into a bookstore now, that's what's there in the diet section. Pritikin may be down in the corner. Atkins is all over. And people say, "Look, on the Atkins diet, I lost a lot of weight." So does it work? Is it a good thing or not?

Well, short-term, it does produce weight loss in people because, first of all, you're eliminating the chocolate cake, you're eliminating the bread and butter, you're eliminating the potato chips and the french fries. If you go to a restaurant on the Atkins diet, 60 to 70 percent of the calories that you would normally eat in that meal, you can't have because they have too much carbohydrate in them. Now, they may also be high in fat. But Atkins says you can eat the butter as long as you don't eat the bread. Who's going to eat the butter without the bread? You see? So it's a gimmick to get people to give up some of these fattening foods, which I said make people fat.

Now, the problem with the Atkins diet is that at some point you're going to have to eat enough calories to maintain a healthy weight. And research has shown that when people follow a high saturated fat and cholesterol diet, even if their carbohydrate intake is extremely low and they stay in ketosis, that cholesterol levels may go up 50 percent or more. And that undoubtedly would lead to clogged arteries. So maybe, I would say, it might be not a bad way to go if your goal is to lose weight and you don't care about your health. But if health is your goal, I don't see following that diet long term.

So short term, for people who say they're losing weight on Atkins, they may be right. But long term, you're saying it's actually a threat to their health?

Yes. I mean, look. We have data from the National Weight Control Registry, where they've actually been gathering data on people who've lost a lot of weight and kept it off, long term. These successful Americans who've lost weight and kept it off -- very few, maybe 1 percent -- are actually following these low-carb, high-fat diets. The vast majority of people are eating high-fiber foods, lower-calorie dense foods, they're exercising. They're doing most of the things or all of the things that we're suggesting people do to be healthy, and they're losing weight and keeping it off as well.

Probably the most provocative article I've read, researching this show, was by a guy named Gary Taubes in the New York Times Magazine. I'm sure you're familiar with this. And he basically says a couple of things, but starting with the idea that basically you people, the Pritikin people among others, have demonized fat, but that fat is actually something we need.

Yes. Well, we haven't demonized fat. We've simply discouraged people from eating a lot of refined fats and oils, and a lot of saturated fat and hydrogenated fat. And the reason we do that is because those types of foods are bad for your health and they promote obesity, because they don't provide much satiety. So we haven't demonized fat. In fact, we encourage people to eat a little bit of fatty fish, and to eat whole grains and beans and things that have "good" or essential fat in them.

So not strictly eliminate fat, because you do need certain fats.

You do. There are essential fatty acids, and nutritionists have recognized this for many years. But the truth is, the requirement for fat for the human body is probably no more than 2 or 3 percent of the calories.

Now, the other charge is that: Look at America. People have been doing Pritikin low-fat diet for a long time. It's been around for quite a while. And yet in that same period of time, people now say there's an obesity crisis. It's an epidemic. So someone like Gary Taubes blames that on the low-fat diet advocates.

That's pretty naive, because let's face it, if you look at the data, Americans aren't eating less fat today than they were 10 or 20 years ago. What's really happened is, the percent of calories from fat has dropped a little bit, because Americans are eating so much more refined carbohydrate -- sugars and refined grains -- things that we tell people, and have always told people, to limit in their diet.

We've talked about this before. You yourself agreed that Americans are getting too fat. We're an overweight society. What are the basic causes of that? What should we worry about most? Why is it happening?

It's happening for two fundamental reasons. One is, we're becoming far too sedentary. And the more sedentary you are, the easier it is to put on body fat.

The second major reason is the diet that most Americans eat. It's low in fiber. It's high in refined grains, sugars, and saturated fats and hydrogenated fats. This makes it very low in terms of what we call satiety, or how full you feel when you eat a certain amount of calories. The result is, you have to eat more calories to feel satisfied. By the time you feel satisfied, you've eaten too many calories. You're not exercising and burning it up. The natural consequence is increased obesity.

But people who claim that high-carbohydrate diets are fattening should take a look at the Japanese in the 1970s. They were eating a diet which was mostly carbohydrate, mostly rice. Very little in the way of fat and protein, relative to what Americans eat. And were they obese? No. In fact, the Japanese are getting fatter today, eating more fat and eating more protein.

Getting an American diet, right?

And they really are eating more meat and cheese and animal products full of fat. And they really are eating more fat. And they're eating less carbohydrate. So if anything, if you look at all the data, more research suggests that as you increase fat in the diet, people have more trouble with their weight. And that's what most research has shown.

One other question about these other diets that seem to be very popular right now, South Beach diet, another one I see in bookstores, everywhere. That diet says: Lay off white flour, lay off white bread, lay off pasta, white rice, and potatoes. They say potatoes are the enemy now.

Yes. Well, look. Probably it's better than an Atkins-type diet because it's eliminating a lot of the saturated fat. But you still have this problem. Claiming that, for example, a baked potato is a fattening food, when in fact research has shown that of all the foods tested to date for their satiety value -- how full they make you feel with a given number of calories -- the potato scored the highest. And the claim that you can make a potato less fattening by adding butter and sour cream to it, or making it into a french fry or a potato chip, flies in the face of common sense as well as all the scientific research I'm aware of.

Common sense. If you talk to my wife, she says, "Look, it's very simple about diets. You just eat good, obviously healthy food. Everybody knows potato chips aren't good for you. You eat carrots, you eat good food, you eat lean chicken. You eat it moderately, and you exercise. At least you walk every day. And then you should be okay." Isn't that basically right?

I suspect that most Americans know what to do, but they don't want that solution. They want something that's quicker and easier and more glamorous. And that's why they try these fad diets. …

So doctor, you read the Atkins diet and they say: Look, I can lose weight and I get to eat steak. Now, why would I not do that, when Pritikin is saying no steak, low fat. Seems a little hard to stick with.

Well, they eat the steak but they can't eat the potato with the butter and the sour cream. They can't have the chocolate cake. They can't have the bread and butter. I mean, you're deprived on the Atkins diet, but you do get to eat the steak. The steak is better than the chocolate cake, as far as your weight is concerned. But both cake and steak are loaded with saturated fat and cholesterol, and they're both going to clog up your arteries. So maybe you're thinner with the steak, but you're still -- what's the point of looking thin in a casket?

That's a horrible idea. But you're really saying, if I did that diet, and I was eating a lot of steak and I kept that going in the long run, not just as a short-term weight loss, that's what I'm doing? I'm clogging my arteries?

Sure. Why has the American Heart Association, every other responsible organization out there, warned people not to eat diets high in saturated fat and cholesterol -- meat and cheese and fatty dairy products? They're doing it because they're concerned about the health of Americans. And there's no doubt that a low-carb, high-fat diet, full of animal products, is going to promote heart disease. It's going to raise cholesterol, it's going to clog people's arteries, they're going to have heart attacks, they're going to have strokes, and they're going to have an increased risk of colon cancer, probably osteoporosis, kidney stones. There's a lot of health problems associated with these types of diets.

So this has got to drive you crazy. You're a crusader for Pritikin and for the low-fat diet. This has got to drive you crazy, that in the last 10 years these diets, these other diets, have caught on.

… As a health professional, it's very frustrating to see people being misinformed about what it takes to lose weight and keep it off and be healthy. That worries me, because we live in a country where people can get away with saying just about anything. Nobody checks the facts in a popular diet book. Every popular diet book I've read, I can find numerous factual errors that conflict with known scientific research. The problem is that most people don't have Ph.D.s in nutrition. They don't understand what's fact and what's fantasy. They buy into the fantasy, but the fact is, they end up harming their health in the long run.

If I were to come down here [to the Pritikin Longevity Center], what would I do in a week? What would happen to me?

Well, we educate people. This is a health education program, first and foremost. We show you how to read labels, so that you end up buying foods that are actually good for you rather than stuff that's just labeled with big print, "no fat." You could put "no fat" on a box of sugar. That doesn't make it healthy.

Isn't that the problem? That "low fat" really caught on, the idea? And then the food processing industry turns it around, puts "low fat" on everything, and you think, "Oh, that's a lot better than fat," but there's other stuff in it you shouldn't be eating, including sugar.

Yes. Low fat doesn't mean low calorie, and it doesn't mean it's low in calorie density and it's high in fiber and nutrients, the way fruits, vegetables, whole grains, and beans are. If people want to eat low fat, they should eat a diet full of fruits, vegetables, whole grains, and beans, not full of fat-free cookies, cakes, and chips. That is fattening, and that is bad for your health too. And one might even argue in some ways that it's nearly as bad as eating high animal fat foods.

So low-fat yogurt that has a lot of sugar, some kind of fruit flavoring in it, low-fat muffins -- kind of a trick, right?

Yes. It is a trick, because these foods have a very low satiety value. They have a lot of calories and they don't have much satiety, so people have to eat more calories before they feel full. You cannot equate low fat with health. It has been demonstrated beyond any reasonable degree of uncertainty that the ration of fat to protein or carbohydrate in the diet is not the key to good health. The key to good health is eating foods that have more fiber, nutrients, vitamins and minerals, and eating foods that don't have a lot of salt, saturated fat, cholesterol, sugar and refined carbohydrates.

A simple message that doesn't necessarily sell diet books, right?

Probably not. But the truth is sometimes not as exciting as the reality. I mean, the truth is sometimes not as good as the fantasy.

One last question for you here. I saw in there, there are some people who look like they're in very good shape, there are a lot of people, maybe first timers, who look like they really need to be here. What's the recidivism rate? How many people work out here, get in good shape, you send them off, and they come back a year later and they've got to start all over again?

Well, it's difficult to say. Certainly there are a lot of people who are very successful long term, and keep coming back and keep sticking with the program. And there are people who slip and slide.

Look, here's what I tell people. If you look at people who've quit smoking successfully, most of them tried and failed five, six, seven times before they succeeded. … And so we encourage people to keep coming back until they get it right, because this is really a matter of life and death. It's not just about the vanity of losing 20 or 30 pounds. This is about your arteries that feed your brain, your heart, your risk of cancer, diabetes. The diseases that most Americans worry about are what this program is designed to prevent and even reverse. …

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posted april 8, 2004

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