The Low-carb Craze Are These Diets More Than A Quick Fix?
In restaurants and supermarkets, the message is becoming inescapable: carbs are bad.
The popularity of low-carbohydrate regiments such as the Atkins Diet and the South Beach diet has reached saturation level, with restaurants scrambling to highlight low-carb offerings on their menus and food companies rolling out lines specifically aimed at this new breed of dieter.
But do the diets actually work?
The verdict, doctors say, is still very much in doubt. While the diets seem to spur short-term weight loss, the long-term effects remain the subject of much debate.
But since when has patience and study been preferable when dieters can have their cake — OK, maybe not cake, but definitely bacon and cheese — and eat it too?
“Patients love it,” said Dr. Christopher Keroack, medical director of the Comprehensive Weight Management Program at Mercy Medical Center. “They love the idea that, if they can name one type of food as the enemy, they can have assurance in everything else.
“That’s the American way — I can have everything my way. It’s rugged individualism, and it sells. If people thought they could eliminate tomatoes from their diet but have everything else, that would sell just as well. Everyone is dying for a quick answer and is not willing to suffer short-term pain.”
Indeed, some 24 million Americans — almost 10{06cf2b9696b159f874511d23dbc893eb1ac83014175ed30550cfff22781411e5} of the population — are currently on diets that restrict bread, french fries, alcohol, and other carbohydrate-laden foods and allow them to eat as much beef, bacon, cheese, and other high-fat foods as they want, based on the idea of a link between lowered carbohydrate levels and decreased fat storage in the body.
And the popularity of low-carb diets is only growing. Opinion Dynamics, a Cambridge, Mass.-based market research firm, recently reported that an additional 20{06cf2b9696b159f874511d23dbc893eb1ac83014175ed30550cfff22781411e5} of Americans say they are likely to hop on the low-carb bandwagon on the next two years.
In short, even if the late Dr. Robert Atkins is already a household name, more and more households are paying attention — and companies that put food on the table and in restaurant booths are reaping the benefits.
Gradual Revolution
Atkins was a cardiologist who first published a book on low-carb diets back in 1972. But it wasn’t until Dr. Atkins’ New Diet Revolution was published 20 years later that his ideas began to capture the imaginations — and palates — of dieters.
The 1999 reprint of that book, and a series of other tomes that followed, have been consistent bestsellers. Another cardiologist, Dr. Arthur Agatston, tweaked the Atkins formula, allowing certain ‘good’ carbohydrates as part of a balanced diet, and his book, The South Beach Diet, soared to the top of bestseller lists as well.
The idea behind low-carb diets is simple, Keroack said. If a dieter limits carbohydrate intake, he reduces the body’s insulin production. Insulin secretion produces an anabolic hormone — a storage hormone, as it were — that converts calories to weight. Cutting off that process leads to a reduction in stored weight, which is why type-1 diabetics with low insulin tend to be thin, he said.
The aim of low-carb diets, then, is to force the body to use fat and protein stores, not carbs, as its main energy source — and therein lies the diets’ aesthetic appeal, as people are allowed to eat as much fat-laden food such as meat, cheese, and butter as they want, even as they eschew foods like pasta, bread, rice, and alcohol. Proteins also cause a longer feeling of fullness, Keroack added, causing dieters to desire less food.
“It works well in theory, but there’s no evidence that it works well in the long term,” he said.
Indeed, most people who commit to low-carb diets and follow them correctly do lose weight — sometimes lots of it, and often very quickly. But doctors say that most of the lost weight comes from loss of water and muscle tissue, not fat — which is what dieters really need to lose in order to keep weight off. Keroack said the reason is that diets such as Atkins and South Beach don’t adequately address the calorie problem.
“Any time individuals lower their calorie content, they lose weight,” he said. “I don’t necessarily believe that carbohydrates are as important as calorie content in affecting weight loss. That being said, this diet does work for some people, but I don’t think it’s the solution for the long haul.”
Keroack cited a study published recently in the New England Journal of Medicine to back up that assertion. Researchers conducted a trial involving 63 obese men and women who were randomly assigned to either a low-carbohydrate, high-protein, high-fat diet, or a conventional diet high in carbs but low in calories and fat.
They found that the low-carb dieters saw greater weight loss (about 4{06cf2b9696b159f874511d23dbc893eb1ac83014175ed30550cfff22781411e5} more, it total) than the traditional dieters after six months, but the differences were not statistically significant after a full year.
“Doctors should be telling people that there is some loose science that backs up these diets, but in the end, they’re just diets,” Keroack said. “And diets are ultimately not a long-term solution. It’s the first law of thermodynamics — energy cannot be created or destroyed. Weight cannot be created or destroyed by a mixture of food; you really have to alter the amount of food.”
Cutting Back
That’s precisely what some low-carb dieters are doing, said Maryann Hayes, a dietician and diabetes educator at Baystate Medical Center. She said she has seen weight loss in people using these diets, as well as lowered blood pressure and an improved outlook and attitude. But many are also paying attention to portion sizes like never before.
“Prior to this, people didn’t know just how many carbohydrates are in three cups of pasta, or a bagel,” she said. “Now, they’re looking at carbs on labels and maybe looking at portion sizes and realizing their portions have been too big, and they’re cutting back.”
In addition, researchers in the study found that the low-carb diet was associated with a greater improvement in risk factors for coronary heart disease, leading them to conclude simply that longer and larger studies are needed to determine the long-term safety and effectiveness of the new breed of diets.
Still, Hayes said, there are some downsides. Specifically, many dieters have lost sight of the importance of balance in the diet, and by eliminating all carbohydrates, they’re cutting off an important nutritional source.
“The message has to be that there are some healthful carbohydrates, and others that are not as healthful for us,” she said. “The next step should be educating people in how to select their carbohydrates.”
Americans tend to latch onto “all-or-nothing” fads, she added, recalling the low-fat craze of the 1980s, when many people tried to eliminate all fat from their diets — and many struggled with nutritional deficiencies.
“The emphasis should be on fewer calories, whether they come from carbohydrates, fat, protein, or even alcohol,” Hayes said. “People need to look at portion control of all foods that they eat. Even though that Eskimo Pie may have only two and a half carbs, is that really the best carbohydrate choice you can make?”
Today’s dieters, however, always looking for a revolutionary quick fix, sometimes don’t pause to consider such nuances, as the low-carb boom has proved. And restaurants and food producers are gladly following the trend as well.
Subway, for instance, has launched a pair of ‘Atkins wraps,’ which include cheese, bacon, and an assortment of veggies with either chicken or turkey. And Burger King is pushing low-carb offerings, including a variety of broiled chicken sandwiches.
Meanwhile, even upscale restaurants are whipping up flour-free batter and taking other steps to offer diners Atkins-compliant options. And ‘low-carb’ is bring printed in large type on boxes and bags in nearly every food aisle of the local supermarket, and for good reason — Opinion Dynamics found that 66{06cf2b9696b159f874511d23dbc893eb1ac83014175ed30550cfff22781411e5} of dieters prefer to purchase items with low-carb labels.
“The popularity of the low-carb diet is much greater than previously reported,” said Lawrence Shiman, a senior account executive with the firm. “Our research shows this is truly a revolution, not a passing food fad, and will dramatically impact not only eating habits but also how the food-service industry approaches the nation’s 220 million adult consumers.”
Cause for Concern
That concerns some doctors, who would have preferred to have better long-term evidence of the diets’ safety before the craze hit. Some worry about the effect of losing lean muscle tissue, which is metabolically active and burns calories even while the body is at rest.
A decrease in this muscle tissue can also decrease the number of calories a person needs each day to maintain a proper weight, making it more difficult to control weight after coming off the diet.
Keroack added that the low-carb diets limit antioxidants and fiber, which are cancer-prevention agents.
“And there’s a very narrow window of unforgiveness with these diets,” he noted. “If you eat above the amount of carbs recommended, your biochemical reaction could actually backfire and release more insulin, and you’ll have even more problems.”
The low-carb revolution has also caught the concerned attention of the U.S. Food and Drug Administration, which currently has no legal definition of what ‘low-carb’ language on food packaging really means — but the agency is now scrambling to create such standards, Hayes said.
In the meantime, Keroack stressed, no matter which diet one chooses, there must be a true marriage between nutrition and activity to maintain weight over the long term — but that takes discipline, a concept which is anathema to many Americans.
“I look at diets as a short-term solution to a long-term problem. Lifestyle change is more of a reasonable solution,” Keroack said. “We as human beings will embrace the lies much more readily than endure the truth. And the truth is that fewer calories cause greater weight loss.
“Part of me wishes it was as easy as these diets make it seem,” he continued, “but that’s not scientifically founded. It’s all related to caloric content.”
And right now, that’s not a message carb-crazed America wants to hear.