Are low-carbohydrate products worth the high price tag?
By Kathleen Zelman, MPH, RD, LD
WebMD Weight Loss Clinic - Expert Column
Low-carbohydrate foods are the hot trend in the food industry. Manufacturers, restaurants, and grocery stores have raced to keep pace with consumer demand, offering everything from beer and ice cream to breads and chocolates. For example, Albertson's grocery store used to carry just a few low-carbohydrate items; today, they offer more than 200 low-carb products.
So what does this proliferation of low-carb foods mean? Can these products really help you lose weight and get healthier? Read on, and we'll help you answer these questions and sort out the confusion surrounding our national obsession to lose weight the low-carbohydrate way.
First of all, if you buy a food labeled "low carb," there's no guarantee that it's much lower in carbohydrates than foods that don't carry such a label. Since there are no nutrition labeling guidelines or legal definitions for low-carbohydrate foods, it's totally up to the manufacturer.
It makes little sense to pay more for a so-called ultra-low-carbohydrate light beer containing 2.6 grams of carbohydrate and 95 calories, when a basic light beer has 3.2 grams of carbohydrate and 96 calories! So buyer beware: Read that label before you hit the checkout line. After all, most foods with the low-carb label are certainly not lower in price than their regular counterparts.
But the bigger question in all this is: Should you be cutting carbs at all?
In some circles, carbohydrates have been declared the new dietary villain. But most dietitians don't agree -- and even research has shown mixed results. It's also important to keep in mind that not all carbohydrates are alike.
So Simple, Yet So Complex
Carbohydrates are your body's preferred form of fuel. You need them every day to give you energy. The National Academy of Sciences' Institute of Medicine recommends that 45%-65% of your total calories come from carbohydrates.
Carbohydrates basically come in two forms: Simple carbohydrates are found in fruits, non-starchy vegetables, sugars, and dairy products; and complex carbs in grains, legumes, and starchy vegetables like potatoes and corn.
The carbs that tend to be the culprits in weight gain are mostly refined, like white flour (a complex carb) and sugars (a simple carb). Americans have a passion for sweets and refined foods, which often contain added fats and lots of extra calories. These are the carbohydrates to limit in your diet.
But don't just eliminate those carbs. Replace them with the healthier carbs: fruits, vegetables, whole grains, low-fat dairy, and legumes. Along with their calories, these carbs have fiber, vitamins, and minerals to give you energy while helping you feel satisfied.
Research Weighs In
Its not the carbs but the calories that cause folks on diets like Atkins to lose weight: That was the headline generated last spring from a study published in The Journal of the American Medical Association. Many nutritionists rejoiced as their predictions were confirmed by this study that demonstrated people lose weight on low-carb diets because they eat fewer calories. The bottom line for weight loss is that you must burn more calories than you consume, regardless of where those calories come from -- or so we thought.
But then another study was presented at a North American Association for the Study of Obesity meeting. Lead author Penelope Green, of Harvard University, suggested that people who ate a low-carbohydrate diet could actually consume more calories -- 300 more -- than people on a low-fat diet, yet lose the same amount of weight.
Even the study's authors cautioned that these results were preliminary, based on a very small study (of 21 adults), and that more research was needed. It's also noteworthy that this study was not published, and that the Robert Atkins Foundation (the same Atkins of low-carb diet book fame) was its sponsor.
Other studies have had similar results.
- A 2002 Duke University study showed that obese volunteers who followed the high-fat, low-carbohydrate Atkins diet for six months not only lost more weight, but they also improved their cholesterol levels more than volunteers on a low-fat, high-carbohydrate diet.
- Last May, researchers from the University of Pennsylvania reported that study participants following the Atkins diet lost slightly more weight over six months than people on conventional low-fat diets. The low-carb, high-protein diet was associated with greater improvement in some risk factors for heart disease, but there was no difference in weight loss between the two diets at one year. The study included 63 people and was reported in The New England Journal of Medicine.
- Last April, University of Cincinnati investigators reported that women following a low-carbohydrate diet for six months lost more weight than women following a low-fat diet. Writing in the Journal of Clinical Endocrinology, the researchers concluded that the low-carb diet appeared to have no negative effect on cardiovascular risk.
- A small study reported in the Journal of Pediatrics last March showed that teens on a low-carbohydrate diet lost more weight than those on a low-fat diet. The researchers reported that, contrary to their hypothesis, the diet did not appear to harm cholesterol levels over a 12-week period.
At the same time, some dieters who have followed low-carbohydrate regimes have reported health problems ranging from constipation to heart problems, according to the activist group Physicians Committee for Responsible Medicine.
Carbs Are Not the Enemy
What all this comes down to is that we need to learn more about how carbs work in weight loss. An ongoing, government-funded study may supply some answers. Almost 200 people will be closely monitored while they follow the diet for two years. But in the meantime, we need to be skeptical.
"It does take a little more energy to digest protein than carbs or fat," says Julie Walsh, MS, RD, spokeswoman for the American Dietetic Association. But she firmly believes that at the end of the day, it's the total number of calories you eat that determines whether you lose weight.
"The only good thing that has come from the low-carb craze is that it has served to educate Americans that there are good and bad carbs, and we are definitely over-consuming refined carbohydrates such as sodas and white bread" says Walsh. "As a nation, we need to eat more whole grains and fewer refined carbohydrates if we are going to be successful at weight loss."
Which brings up another important point: Low-carb diets don't do much to teach you how to make good food choices once you go off the low-carb wagon. And, after days or weeks of low-carb dieting, many people find themselves craving carbohydrates more than ever.
Further, while it's possible to lose weight quickly when you begin a high-protein diet, experts believe much of that loss is water. So low-carb still is not the diet of choice for lifetime weight loss.
My crystal ball shows signs that the low-carb trend is headed for the same fate as the low-fat craze did in the '90s. A decade ago, shelves were packed with fat-free products. But these items did little to stem the tide of the growing obesity epidemic. While they were fat free, they were loaded with calories.
Besides, when you're trying to lose weight, you should not be focused on products like cookies, chocolate, beer, etc. whether they're low-carb, low-fat, or whatever. These simply are not the kinds of foods that help you take off pounds. So the next time you're at the grocery store, walk on by those low-carb foods and right into the fresh produce section.
The WebMD Weight Loss Clinic advocates a healthy, balanced diet that you can live with forever. Our eating plan is in accordance with guidelines from all the leading health authorities and government. So stick with us. We'll help you learn about the healthy carbs while you lose weight and improve your overall health and well-being.
Published January 9, 2004