Carb confusion

By Wanda A. Adams
Advertiser Food Editor

Salesman Nelson Choy of Hawai'i Kai has lost 20-plus pounds and four belt notches in the past couple of months following the Atkins diet plan. At the other end of the island, Romy Estrella of Mililani uses a not-quite-vegetarian, high-carbohydrate approach to maintain her size-5 figure and the get-up-and-go she needs in her nursing job.

"I don't understand why people say it's not good for you," Choy said of his low-carbohydrate regimen.

"What I don't understand is how (the two diets) can be so opposite but they both work," said Estrella.

Welcome to carb confusion. Perhaps we can clear up a few things (or perhaps not).

Q. What is a carbohydrate, anyway? And why should I care?

A. Carbohydrates are one of the three primary nutrients containing calories, which the body burns for energy; the others are protein and fat, explained registered dietitian Karen Yafuso, coordinator of bariatric surgery and weight management for Kaiser Permanente here.

Carbohydrates come from plant sources and are made up of sugars and fiber. Simple carbohydrates are sugars (sucrose, fructose, maltose and such). Complex carbohydrates are starches (long chains of sugar molecules). These are broken down into glucose ("blood sugar") in the body and burned for energy or, if they're not needed, stored as fat. Fiber, the structural parts of plants, is indigestible and passes through the system without being absorbed.

Carbohydrates are necessary for life. But how much carbohydrate should you eat? The conventional wisdom has been that 40 percent to 60 percent of calories should come from carbohydrate, in excess of 100 grams a day. Dr. Terry Shintani, author of "The Good Carbohydrate Revolution," advocates a diet of about 75 percent carbohydrate.

The popular Atkins diet begins with a two-week "induction phase" in which carbohydrates are limited to 20 grams a day. The plan allows as many as 90 grams a day (or as few as 25 grams) in the maintenance phase, whatever is required to maintain weight loss. By restricting carbohydrates, the body is forced to burn stored fat, a process called ketosis. Other plans, such as the Zone Diet, balance carbohydrate, fat and protein in a particular ratio.

Q. So what's wrong with carbs?

A. Even the creators of the low-carbohydrate diet plans — Atkins, South Beach, Sugar-Busters, The Zone and others — say there's nothing wrong with carbohydrates, per se. But they argue, as do conventional nutritionists, that there's a lot wrong with chronic overconsumption of refined sugars.

When you eat a carbohydrate, glucose is released into the bloodstream as the food is digested. When all is working well, the glucose is transferred from the blood into the cells (where it can be used) by means of the hormone insulin excreted by the pancreas.

Poorly controlled blood sugar causes cravings and can result over time in diabetes or hypoglycemia. Another condition that is getting attention is insulin resistance or hyperinsulinism, which occurs when long-term overproduction of insulin (provoked by a diet high in sugar) causes the cells to become desensitized to the hormone. Both Dr. Robert C. Atkins, in his "Diet Revolution" book and Dr. Shintani in "The Good Carbohydrate Revolution," detail the ill effects linked to long-term high blood insulin: elevated cholesterol and triglycerides (blood fats) and various changes that may be associated with high blood pressure and obesity.

But not all carbohydrates are created equal. "There are good carbs, there are bad carbs ... You have to learn to choose," said Dr. Laurie Steelsmith, a naturopathic physician and columnist for this newspaper.

At one time, nutrition experts discouraged consumption of simple carbohydrates in favor of complex carbohydrates, because it was believed that the sugars contributed to undesirable spikes in blood sugar but starches did not. More recent research has shown that certain members of both families of carbohydrate can release a rush of glucose, Shintani said.

For example, white bread, a complex carbohydrate, gives you a stronger sugar spike than white sugar or an apple, he said.

This has stimulated interest in a tool called the glycemic index, a measure of how much and how fast a particular food, once ingested, raises blood sugar. Glucose has a glycemic index of 100; barley, a high-fiber, whole-grain food, measures 25. Steelsmith recommends sticking to foods with a glycemic index number below 60. It's said the low GI foods create a longer-lasting feeling of fullness.

But Shintani says knowing the glycemic index of a food isn't enough; you need to balance that against the food's calorie-density — calories per gram — and the size of a normal serving. (For example, 50 grams of sugar — about one-quarter cup — is easy to eat; you'd never eat 50 grams of carrots — 7 whole carrots — at a sitting.) He invented a measure called the Carbohydrate Quotient to take into account both issues.

Q. Glycemic index? Do I really have to keep track of another set of numbers?

A. That's up to you. But know that the glycemic index of a food isn't an absolute. University of Hawai'i lecturer in sports nutrition Alan Titchenal cited studies in which blood sugar counts varied in test subjects who ingested the same quantities of the same carbohydrates; the indices are actually based on an averages, he said. Also, the GI of various types of the same food (white potato, red new potato, etc.) varies. Consult a detailed list.

Says Titchenal: "I don't think this is something that the average person needs to get focused on. ... If you just follow the general recommendations for eating more wholesome foods in a wide variety, we have seen that you end up with a diet that's lower glycemic overall."

But naturopath Steelsmith says if you suspect you are insulin resistant (one indication is the triumvirate of obesity, high blood pressure and high cholesterol) or if you are subject to sugar cravings, the glycemic index may be helpful.

Q. Are low-carb diets just a fad? Are they safe?

A. Here's where the fur flies.

Shintani has a file full of medical studies, years of his own research reports and one question: "The people who are skinniest in the world all eat a high-carbohydrate diet. So how does a low-carbohydrate weight-loss plan square with reality?" He also points out that traditional Eskimos, who eat a high-fat, low-carbohydrate diet, have a high incidence of osteoporosis because of a lack of calcium and are at increased risk for many kinds of cancer, probably associated with low fiber intake.

Low-carb diet proponents say that's comparing apples and oranges; traditional Eskimos didn't have access to calcium-fortified foods, calcium supplements, calcium-rich greens or fiber-rich carbohydrates — all encouraged on these diets, though total consumption is restricted.

Conventional nutrition experts agree that a few weeks of adhering to a very low-carbohydrate eating plan won't harm a healthy person and will result in weight loss. But they have doubts about the long term. Last year, a Stanford University review of low-carb diet studies concluded that people lose weight on the diets because they eat fewer calories. However, the researchers said additional study is needed.

Opponents of low-carb diets raise concerns about a variety of issues — constipation, stress on the kidneys, increase in cholesterol and heart disease, loss of muscle mass, low energy, risk of gout — all of which the low-carb folks counter with their own arguments.

Dennis Muth, owner of Paradise Foods Low Carb and Low Sugar Market in Kailua, says there's a lot of misinformation about low-carbohydrate diets and horror stories that get repeated, some of which can be attributed to under-educated dieters. "You have these people who do their own version and they don't take the supplements and vitamins and they don't make good choices and they don't drink the water and they can get into a little bit of trouble," he said. "We tell everybody to read a book and understand what they're doing."

Kailua nutritionist Nicole Angelique Kerr's big problem with low-carbohydrate is the same as for many other popular diet plans: "It sets up deprivation and restriction and any diet that does that is not going to work long-term."

Nutrition consultant Susan Kim of Honolulu isn't too worried about the safety issue: "Most people don't stay on any diet long enough for it to harm them," she said. "They're going to go back to eating carbs."

Kaiser Permanente's Yafuso shares this view: "I see weight loss all the time. What I don't see is weight management. What the patient does to lose the weight doesn't seem to matter; what does matter is how they keep it off. And most of these fad diets just aren't sustainable over time."

Q. Isn't there anything that everyone can agree on?

A. Yes, some key points, actually, which serve as a guide to changes you can make in your diet to improve nutritional habits and long-term health.

• Avoid "white carbs" — white sugar, white flour. Instead, eat as low as possible on the food chain. "The bottom line is that people need to eat a whole food diet. Whole foods are those that are as close as possible to their original form — brown rice, whole-grain breads, fruits and vegetables," said naturopath Steelsmith. "They are digested more slowly and they don't cause as rapid a rise in blood sugar. And they contain fiber."

Fiber, which is indigestible, is desirable because it's bulky, helping you feel full and satisfied more rapidly. Fiber also acts somewhat like a new broom that sweeps clean — pushing cholesterol, toxins, bile and harmful bacteria through the system and promoting normal elimination. Muth points out that the low-carb diet allows you to subtract fiber content from total carbohydrates, to get what they call "net carbs."

• Eliminate "liquid sugars" — sodas and juices. "Even if it's pure juice, it's still sugar," said Kerr.

Drink water instead; it rehydrates you, helps to wash out toxins, has no calories or caffeine and offers many other advantages, Steelsmith said.

• Get a move on. "Physical activity is key," said Titchenal. "As far as blood glucose management is concerned, exercise is like getting a shot of insulin; it really helps manage your blood glucose levels."

Both Atkins and Shintani devote a chapter to the importance of exercise in their books, Atkins calling it "non-negotiable."

Test your carb savvy

Clockwise from top left: red kidney beans, dried peas, whole wheat pasta, passion-orange juice, avocado, asparagus, beets, kale, brown rice; center, low-fat granola. Bruce Asato • The Honolulu Advertiser

2. Which is highest in "net carbohydrates" per serving, meaning total carbohydrates minus dietary fiber?

3. Which of these foods contains no fiber?

4. Which of these foods would be off-limits during the "induction phase" of the Atkins diet? Which would be off-limits during Phase 2?

5. Which of these foods might be off-limits in a high-carbohydrate diet such as Terry Shintani's "Good Carbohydrate Revolution"?

6. Can you list carbohydrate content from most to least, per serving?

For answers, click here

High-carb, low-carb diet — what's the difference?

• Dr. Atkins' Diet Revolution: White sugar and flour and foods with high sugar concentration prohibited. Fruits prohibited or limited.

Vegetables limited with raw salad greens favored over more dense varieties. All meat, fish, shellfish, fowl, eggs allowed. Other animal foods allowed, though limited. Artificial sweeteners and thickeners suggested. Supplements required.