Speaking With...: David L. Katz

David L. Katz, M.D., M.P.H., F.A.C.P.M., F.A.C.P is a board-certified specialist in Internal Medicine and Preventive Medicine as well as associate adjunct professor in public health practice at Yale School of Public Health.

He is also the founder and director of the Yale Prevention Research Center and the Integrative Medicine Center.

Hundreds of television and print appearances have made him familiar to millions of people in the United States and around the world.

Some of his most high-caliber gigs? Health columnist for the New York Times; nutrition columnist for O (Oprah's magazine), nutrition consultant for VH1's Celebrity Fit Club, and medical contributor for ABC News.

He has also made multiple appearances on Larry King Live, Oprah, The Today Show, 48 Hours, Good Morning America, World News Tonight, and 20/20.

The American College of Preventive Medicine noticed all his potential and presented Dr. Katz with its Rising Star Award in 2001.

Dr. Katz' extensive knowledge of -- and research on -- weight management and chronic disease earned him the title of one of the country's top preventive medicine physicians by the Consumers' Research Council of America in 2003, 2004, and 2005.

I contacted Dr. Katz to discuss some of today's hottest nutrition issues, as well as the release of his new paperback, "Dr. David Katz's Flavor-Full Diet: Use Your Tastebuds to Lose Pounds and Inches with this Scientifically Proven Plan," which introduces the concept of "sensory specific satiety."

Read on to find out exactly what that is, and much more, in my exclusive chat with Dr. Katz.

The research on sensory-specific satiety presented in The Flavor Point Diet [hardcover title] brings a new and different approach to weight loss and maintenance. When did you first become aware of these studies, and how did you start developing and molding it into your book?

I first learned of sensory specific satiety in 1991, while examining factors that influenced dietary choices – and overeating – during my preventive medicine training. I was immediately fascinated, recognizing this as a powerful, universal force, but a topic people did not know at all.

It occurred to me that sensory specific satiety – the tendency to fill up faster when there is less variety in a given meal or snack, and to stay hungry longer when there is more variety – was the reason why, at the end of a large holiday meal, right after saying we’re too full to eat another bite, the next words out of our mouths are: “What’s for dessert?”

It is also the reason why everyone overeats at an all-you-can-eat buffet.

The research on this topic goes back thirty years, but no one had tried to leverage the power of this tendency to help people fill up on fewer calories and control their weight. That, I suppose, is the novel idea for which I get credit. But I owe a debt of gratitude to the appetite researchers and neuroscientists who worked out sensory specific satiety in the first place.

I began thinking about it in 1991; applying it to patient care in 1993; writing about it by 1995; and incorporating it into my books in about 1997. I wrote Flavor Point (the paper back is Flavor Full Diet) from 2003 to 2005.

During that time, I worked with my wife [an expert cook] to turn my understanding of this powerful force into a meal plan that could help people control appetite in a whole new way, while preserving balanced nutrition and the pleasure of eating good food every step of the way.

Did you ever worry that some of the advice can be misconstrued? For instance, someone starting out on the diet might be deterred from eating a nutritious, healthy snack like apple slices and walnuts on "pineapple day" [one of Flavor Points' theories is to keep a consistent flavor throughout the day] , while someone else might get confused and think that salt-free potato chips and club soda are a better snack than, say, air-popped popcorn and piece of fresh fruit.

The book is very explicit about placing good nutrition first and foremost. And it also explains the role of flavor themes.

But, yes, there is the risk of getting too preoccupied with the idea of flavor themes. To be blunt, they are a gimmick.

Not in a bad way; a gimmick is defined as ‘an ingenious device’ for some purpose. I found that the flavor themes helped people understand what organizing flavor meants. It helped them focus on flavors over the course of a day. So, flavor themes help people “get it”, and learn how to distribute flavors thoughtfully.

But otherwise, they are totally unnecessary. What makes the flavor point meal plan work is the avoidance of too many flavor categories (sweet, salty, savory, etc.) jumbled together into any given food, meal, or mouthful. The flavor theme helps a little by providing subtle repetition throughout the day, but it’s really the avoidance of mad jumble of unnecessary flavorants all at one time that gets the job done.

Publishers like what they know, and in diet books, what they know is plans with several, progressive stages. But if I had flavor point to write over again, I would eliminate that. The book teaches a new concept, and a new skill; you can apply it without the rigidity of flavor themes. They clearly help some people, but I think they may distract and even discourage some others. If they help, use them; if not, you can ignore them and apply the concept.

The concept is this: identify and choose more wholesome foods by knowing how to read a good label, and you avoid unnecessary sugar added to salty foods; unnecessary salt added to sweet foods; and artificial flavorants added to most processed foods. All of these additions turn on appetite responses, and make you need more calories to feel full. The “bet you can’t eat just one” ad was a threat the food industry really could back up!

There are popular breakfast cereals with more added salt than potato or corn chips; there are popular pasta sauces with more added sugar than chocolate fudge sauce. This is not by accident; these hidden flavors (and they are hidden; who likes salty breakfast cereal or pouring high fructose corn syrup over their spaghetti?) put your appetite center into overdrive.

When you need extra calories to feel full, you have a choice: gain weight, or go hungry. Flavor Point offers a third choice: learn how to avoid this trap, fill up on fewer calories, avoid weight gain, and but still eat until completely satisfied.

How, if at all, does sensory-specific satiety tie into what I like to call the "three pillars" of satiety (fiber, fat, and protein)? Did you find that a meal high in these three nutrients is less effective in helping someone feel satiated if it combines too many flavors at once?

They are complementary concepts. Foods that are wholesome and close to nature tend to be best for avoiding a mad jumble of flavors. Such foods tend to be high in fiber, too; and to have a low glycemic load, high quality protein, etc.

Flavor Point focuses on the thoughtful distribution of flavors, since that is the novel concept it is introducing. But into the bargain, the meal plan and advice in the book address everything else we know about appetite control, from macronutrient composition, to glycemic load, to volume.

The bottom line is: healthful eating helps control appetite in a variety of ways. Put them all to work for you, and the effect is very powerful.

I would like everyone to be in my position: eat food you love, until you are full, and never worry about your weight. I can gain weight as easily as anyone else, but since I full up on the “right” number of calories, I never do. Add use of sensory specific satiety to other strategies for filling up on fewer calories, and that’s the result you get.

There are certain natural, healthy foods like milk which naturally contain sodium and sugar. How do these play into sensory-specific satiety? Are they seen as equal to processed cereals that contain these two flavors?

Wholesome foods from nature generally have a clearly dominant flavor; milk is certainly more sweet than salty. In fact, such foods do turn on more appetite than they would if they did not contain this combination.

It makes sense, for instance, that breast milk would turn on appetite to help ensure that newborns eat enough. It is not actually “normal” for adults to consume dairy; that’s why so many of us are lactose intolerant.

But in fact, I am not worried about such foods. Eliminate the enormous influence of processed foods and buffet meals on appetite, and the effect of flavor combinations in natural foods is modest in comparison. It’s just not a problem.

Like all reasonable theories, sensory specific satiety could be pushed to extremes where is is no longer useful or sensible. That is to be avoided, of course.

The field of nutrigenomics is a fairly new one that promises to keep growing over the next few decades. Do you think further research will provide breakthroughs in the field of preventive medicine and nutrition? As a renowned professional in the field of medicine, are there any specific issues or topics you think it holds the key to?

No question. Nutrigenomics will help us know what specific dietary adjustments are most important for a given individual to help avoid adverse outcomes or promote health.

But, let’s face it: we don’t need to catalog the genes of individual lions to know they should eat meat, or the genes of individual koala bears to know they should eat eucalyptus leaves. We are the same. We have a basic native dietary pattern that does, and always will, make sense for all of us.

Nutrigenomics will allow for individual tailoring, but it will still be variations on a theme – and we have a sound knowledge of the theme right now.

What is your take on the new batch of "superfoods" (i.e: hemp, goji berries, mangosteen, borage oil, acaí)? There is no doubt they have health-promoting properties, but don't you think they are often given too much credit as being miracle foods when, in reality, what we need to start with is encouraging people to develop healthy eating patterns that can include tried and true classics like pears, olive oil, and oatmeal?

What we need is strategies to help people adopt a healthful diet. We have no real evidence that any single super food will change health outcomes. We do have evidence that a healthful dietary pattern can provide lasting weight control, slash diabetes risk by at least 60%, slash heart disease and cancer risk, reduce the risk of osteoporosis, prevent allergies, etc.

But, it is much easier to sell people a single food than get them to adopt a healthful diet, hence the marketing effort for superfoods. Nothing against them, but there is no silver bullet when it comes to health. You have to find the forest, not get stuck picking a super fruit up a single tree.

That’s why what I write about is “how to,” not “what”. We know what a healthful diet is; people need new strategies, and knowledge, and skills to help them get from there to here. That is the focus of my work.

When it comes to overall health and risks for certain diseases – just how much, if any, damage can damage be reversed? Let's take someone who mainly ate processed throughout their 20s and, ten years later, did a 180 and made whole grains, fresh fruits and vegetables, nuts, legumes, and lean protein staples in their diet. Even though they are now eating better, are they actually "undoing" past damage on a cellular and organ level?

Absolutely, yes. Obviously, the later the conversion to healthy living, the more damage there is to undo it, but no question.

It’s never too late to start being healthy, and there will always be benefits of doing so. One thing people often overlook about those benefits – they won’t just be for you.

Start eating well when you are in your 30s and 40s, and, sure, you have some damage to undo. But you are also a role model for your children, perhaps, and helping them adopt healthful habits before ever any damage occurs.

The benefits of healthful eating extend to other members of your family if you approach this as a family affair. Everyone wins.

A lifetime of good health is the greatest of all blessings, and the best gift a parent can give their child. With the right application of both will power, and skill power, it is within reach for most of us.

Many, many thanks to Dr. Katz for his time and insightful, detailed answers.