Posted on Wed, Jul. 16, 2003

Critics roast raw foods diet

Experts say cooking is necessary to release some foods' nutrients

By Shari Rudavsky

Knight Ridder Newspapers

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Until the death of a severely underweight infant whose parents followed a raw-food diet, the term ``raw food'' was more likely to conjure images of sushi, oysters or carpaccio than of crunchy greens.

Indeed, ``going raw'' has a certain cachet in quarters far from the modest apartment in Homestead, Fla., where 5-month-old Woyah Andressohn lived. (Born at 7 pounds, Woyah weighed one pound less when she was pronounced dead on May 15.)

Investigators said they thought Woyah may have died of malnutrition. According to state authorities, the family's four other children were severely malnourished.

Celebrities such as Woody Harrelson swear by the diet's salutary effects. Restaurants featuring all-raw menus have opened in California, New York and Miami Beach.

Foods proponents argue that a diet of uncooked vegetables, fruits and nuts reflects a natural way of eating. Fire changes the molecular structure of food. The theory holds that heating food above 118 degrees will kill the enzymes, diminishing its nutritional value. Pointing to nature and how no animal cooks its food, proponents contend that raw food is more alive than its cooked counterpart and, therefore, better for us.

``This is about the understanding that if you eat more food that has its life force still intact, that's going to be better for us,'' said Fred Busch, a raw-foods adherent and co-owner of a raw market and deli in Miami Beach. ``This means that there's life force in the cells and that's what's feeding us.''

Not so, say many nutritionists and scientists. While some raw foods will enhance your diet, an eating plan consisting totally of uncooked foods puts anyone -- particularly the young -- at the risk of nutritional imbalance.

Although raw fruits and vegetables are packed with vitamins, a raw diet, without dairy or meat, may have too little protein and too few fatty acids, which experts say are essential to growth and health.

In addition, nutritionists say some vegetables offer more nutrients when cooked, as the heat makes them more accessible to the human body.

``The burden of proof is on them to show that it's a better diet,'' said Linda Bobroff, a professor of nutrition at the University of Florida in Gainesville. She said that years of research stand behind the U.S. Department of Agriculture food pyramid and recommendations for a solidly balanced diet with a mix of raw and cooked foods.

Stan Glaser, owner of Glaser Farms in Redland, Fla., counters that science has yet to offer him proof that the mainstream diet is better. Over several years, Glaser experimented with different ways of eating, including raw foods.

At one point, he subsisted only on green leaves and fruits, but he has added raw vegan foods such as nuts and seeds. Glaser scoffs at the standard nutrition line.

``They lead you to believe that you have to be a Ph.D. in nutrition to know what to eat. I find this ludicrous,'' he said.

Instead, he advocates a diet more akin to that followed by our ancestors and other species. By doing that, Glaser said, we will hit upon a diet that not only worked well for our forebears but will also work for us.

``If you limit what you eat to the uncooked vegetables, foods which have always been available to us, then you can trust your taste,'' he said.

Movement's history

The raw foods concept dates back at least to the 1920s, when German writer Arnold Ehret published his account of how a raw foods diet helped restore him to health.

A few years later, Ann Wigmore, also an alternative healer, propounded her own theory of living foods -- uncooked fruits, vegetables, beans, sprouts, nuts and wheat grass -- that she argued would detoxify the body. Her Hippocrates Health Institute helped spread the word.

While adherents say the diet helped them shed pounds and energizes them, nutritionists remain skeptical.

``We don't have any research to indicate that this is a better way to eat,'' said Cynthia Sass, a spokeswoman for the American Dietetic Association and a dietitian based in Tampa, Fla.

If anything, the research that does exist pokes holes in the raw-foods diet. While cooking produces chemical changes, it does not change the molecular structure of food completely, said Robert Wolke, emeritus professor of chemistry at the University of Pittsburgh.

The claim that enzymes are destroyed at 118 degrees is also specious, he said. There are more than 1,000 enzymes, and each has its own critical temperature.

``It's like saying that all substances melt at 32 degrees Fahrenheit. It's nonsense. Ice does, but rocks don't and peanut butter doesn't,'' Wolke said.

That's not to say that there aren't some advantages to raw foods.

Overcooking vegetables can decrease their vitamin content, particularly vitamins B and C. Cooked vegetables may also come with excess salt or butter, while raw ones come with few extras and lots of fiber.

On the other hand, heat kills microorganisms or other toxins lurking in food. Soybeans contain substances that in large quantities will interfere with digestion and absorption of zinc and iron. Cooking disarms these blockers, according to the American Dietetic Association.

Other foods just offer more benefits when cooked. Tomatoes do not release lycopene, a substance that appears to prevent disease and even cancer, unless cooked.

And despite conventional wisdom that cooked carrots have less beta carotene, scientists now say that we get more beta carotene from cooked carrots because the heat makes the nutrient more accessible. Beta carotene is thought to have a role in preventing cancer.

Mainstream nutritionists conclude that the answer is not all-raw or all-cooked, but a combination.

Nutritional balance

Even those who espouse raw foods agree that it's not simply a matter of eating vegetables. ``The key is not just to say raw food,'' said Brian Clement, director of the Hippocrates Health Institute in West Palm Beach, Fla. ``If you say that to somebody without an education, they could be eating lettuce and apples. You have to be well-balanced.''

Adults who avoid cooked food and fail to eat nutritionally balanced diets may suffer fatigue, muscle injuries or decreased immune function. Children need high levels of protein to help them grow. They also need vitamin D. It's found in milk, but milk is forbidden in a raw foods diet.

For infants, a raw food diet is even more ill-advised, nutritionists say.

``People think this is healthy. No, it's not healthy, certainly not for infants,'' Bobroff said. ``Anyone who tries to feed an infant (who is) under 1 year of age any diet meant for an adult is maltreating that infant.''

Raw foods also tend to fill you up quickly, so you may stop eating long before you've met your nutritional needs.

``A cup of vegetables may only have 25 calories, but it's very filling. You can imagine how many cups of vegetables that are raw you would have to eat,'' Sass said. ``The total caloric intake could easily become inadequate.''

Then there's the simple notion of deprivation. The diet rules out piping hot soup, warm pastas and desserts featuring rivulets of melted chocolate.

Enthusiasts such as Busch, who went raw three years ago, say uncooked does not mean untasty. His deli features pizza made from nuts and flax bread, nori rolls (the seaweed wrappers often used in sushi) and ice cream from frozen bananas.

And at Roxanne's, the raw-only restaurant in the San Francisco area, you can order fine wine to accompany your meal of lasagna terrine layered with roma tomato sauce, mushrooms, baby spinach, corn and herbed cashew cheese.