Science al Dente
Nowadays, one cannot enter a supermarket, quick-service or sit down restaurant without hearing or reading the words “low-carb.” The phrase, by definition, deems foods like bread, cake and pasta as bad news.
However, for some, low-carb is “the good news:” a gospel that invades national news sources and food choices. The birth of the low-carb phenomenon has put to task every definition of what characterizes a healthy diet--even to the extent that many are calling for an updated food guide pyramid.
However, one high-carb product, pasta, is fighting back. K. Dun Gifford, founder and president of The Oldways Preservation Trust, a Boston-based nonprofit think tank on food issues, vehemently opposes the concept that pasta is unhealthy and advises that the onslaught of information about the dangers of carbohydrates is false. In February 2004, Oldways scheduled a three-day conference in Rome, Italy, the heart of pasta country, to defend the honor of a food product it considers a healthy staple in family meals throughout much of the world.
When in Rome ...The attendees of “Healthy Pasta Meals: An Oldways Scientific Consensus Conference,” were comprised of scholarly medical scientists and doctors, chefs and dieticians armed with concurring research that opposed the low-carb revolution. The information was collected independently of the pasta industry--such as the company Barilla (Parma, Italy)--that sponsored the conference. At the conclusion of the conference, 34 scientists, doctors, and dieticians from America, Italy, Greece, France, Canada and Australia signed the consensus announcing their confidence in the healthfulness of pasta in the context of a Mediterranean diet, which some consider the gold standard.
Ironically, some controlled carbohydrate advocates agree with the pasta brigade in one respect. “We are very supportive of the Mediterranean lifestyle, when whole foods dominate the menu options,” says Colette Heimowitz, vice president of education and research at Atkins Health and Medical Information Services (Ronkonkoma, N.Y.). [Ed.'s note: Heimowitz did not attend the conference, but agreed to a telephone interview.]
Both sides--low-carb corroborators and healthy pasta loyalists--maintain the low-fat diet recommendations of the 1990s accelerated and coincided with the obesity problem that now consumes the globe. The Oldways' consensus advocates a moderate or reduced consumption of highly refined and processed carbohydrates like white breads, potatoes, rice and foods containing added sugar due to their high glycemic index.
According to Oldways scientists, the truth lies not in low-carb vs. high-carb foods but rather in which foods will impact a meal's “glycemic load,” a term coined in 1981 at the University of Toronto by Healthy Pasta Consensus Committee Chair Dr. David Jenkins, a professor of medicine and nutrition at the University of Toronto (Canada).
Glycemic Index DefinedThe glycemic index (GI) measures how rapidly a carbohydrate-laden food triggers a rise in blood sugar; the higher the number, the greater the blood sugar response.
Every food has a different GI, and it is not dependent on the amount of carbohydrates contained. For example, the GI for a potato is 60 (baked) while the GI for most cooked pasta meals is 41. Factors influencing the GI are the rates of gastric emptying and glucose absorption. The consensus advises that slow gastric emptying is preferable to rapid dumping of glucose, because glucose uptake is beneficial when gradual, but harmful when abrupt. Factors that determine gastric emptying rates include the presence of fats, proteins and alcohol, all an integral part of the Mediterranean diet. “A slow-release food like pasta is associated with reduced cardiovascular disease,” informs Jenkins.
Although pasta recently has been included in the lineup of usual suspects for the crime of abetting obesity, Oldways scientists have provided an explanation. Pasta conference participants reiterated that pasta represents a vehicle by which other healthy foods enter the body. Throughout history, semolina pasta made from coarsely ground triticum durum wheat has been associated with the Mediterranean communities where pasta is eaten with fat in the form of olive oil, nuts, whole grains and plenty of fruits, vegetables and fish. “Pasta's partners on the plate are tomatoes, olives, spinach, zucchini, broccoli, eggs, legumes, beans, chick peas and other low-glycemic index vegetables. Nobody eats a single ingredient,” says Gifford. “They eat a pasta meal--pasta with other ingredients.” The multiple ingredients carry with them their own health-promoting benefits, providing essential macronutrients in desirable forms.
Following a different premise, controlled carbohydrate dieters adhere to the edicts of doctors and authors like Arthur Agatston (The South Beach Diet) or Robert C. Atkins (The Atkins' Nutritional Approach), who purport to also use forms of the glycemic index. “The Atkins Glycemic rating incorporates the glycemic index and simplifies it, [encouraging dieters to] eat regularly, in moderation and sparingly,” explains Heimowitz.
However, that may be where the similarities end. Unlike diet plans that espouse the benefits of the Mediterranean Diet, which is based mostly on the GI invented by Jenkins, many reduced-carbohydrate diets discriminate according to the carbohydrate content and not the GI, say Oldways scientists. “It is false that Atkins is remotely similar to the Mediterranean Diet,” opines Gifford. The Mediterranean Diet prescribes that protein-dense foods containing more saturated fat, such as meat, be eaten only a few times a month, whereas the Atkins diet permits dieters to eat meat daily.
Regardless of a particular foods' GI, Atkins participants are advised to significantly reduce carbohydrates (20 net carbs in the induction phase which, according to Heimowitz, allows five servings of vegetables) at the beginning of their weight loss plan. They can gradually be reintroduced in a stepwise manner, depending on their Atkins Carbohydrate Equilibrium (ACE). In an Atkins diet, even pasta, which has a low GI, should be avoided during the first two phases. Participants are asked to reduce their pasta servings to between one half to one cup during the lifestyle maintenance phase, as opposed to the suggested one cup by the USDA and two cups by Oldways.
According to one consensus participant, “Over-consumption of carbohydrates, in any form, promotes weight gain and may precipitate disease. The same is true for consumption of either of the other macronutrients (fats and proteins).”
All Fats are Not Created EqualU.S. dietary recommendations, which discourage fat intake, have not changed since 1992. Since then, scientists have linked mono- and poly-unsaturated fatty acids (MUFAs and PUFAs) with many health benefits (brain and eye development in children and adults, along with the reduction of LDL cholesterol). In recent years, several studies have labeled low-fat diets as ineffective over the long term, resulting in increased triglycerides, explains Dr. David Ludwig, director of the Obesity Program & Optimal Weight for Life Clinic and associate director for the General Clinical Research Center at Harvard Medical School (Boston). Gifford believes that when the USDA Food Guide Pyramid is revised in January 2005, fat recommendations should increase. Also, citizens should be encouraged to avoid trans-fatty acids and saturated fats, and to eat more healthy fats containing omega-3 and omega-6.
All the same, saturated fat still is considered dietary dynamite. Low-carb diets contend to reduce insulin “spikes” better than other diets, but several panelists, backed-up by a century's worth of extensive scientific data, concluded that it is the diets that are high in saturated fat that impair insulin sensitivity, increase LDL-cholesterol and C-reactive protein (CRP), and are risk factors for Alzheimer's disease, macular degeneration, cancer and osteoporosis.
“There is no study showing that dietary carbs can influence insulin sensitivity,” asserted Dr. Lydia Bazzano, a clinical fellow at Harvard Medical School/Beth Israel Deaconess Hospital (Boston). It has been demonstrated time and again that “too much fat has a relationship with impaired insulin sensitivity. First comes obesity, then insulin resistance,” says Bazzano. Additionally, a diet that is high in fat has been definitively linked to atherosclerosis, diabetes and cancer and it further facilitates the development of obesity, she says.
The panel agreeing on this controversial subject included several world-recognized authorities on nutrition, including Ludwig and Jennie Brand-Miller, professor of human nutrition at the University of Sydney (Australia) and author of New Glucose Revolution.
Most low-carb dieters are encouraged to substitute in more protein and fat to negate the energy they lose due to the lack of carbohydrate consumption. As a result, Atkins dieters eat significantly more calories from dietary fat than what is recommended by the USDA, the American Heart Association (AHA, Dallas) and low-carb diet plans such as South Beach. Oldways' literature reports that the percent of calories from dietary fat in an Atkins diet is 56% (average of the three phases--see chart “Adding Up the Fat”). A significant charge against Atkins, leveled by those at the Healthy Pasta Meal Conference, is that Atkins tells dieters to consume fat liberally, without making a distinction between unhealthy saturated fat and healthy MUFAs and PUFAs.
The Atkins StanceHeimowitz says that Atkin's books encourage the idea of balancing natural fats originating from whole foods, like monounsaturated olive oil, polyunsaturated vegetable and seed oil, with saturated fats like proteins, coconut oil and butter. He dissuaded Atkins dieters from eating trans or processed fats. Heimowitz argues that, despite what the media and their detractors say, “The Atkins lifestyle is high in monounsaturated fats.” However, contrary to what most dieticians and doctors preach, she offers that saturated fat is not as harmful as Atkins critics say. “Individuals who have the symptoms of metabolic resistance, such as abdominal adiposity, high triglycerides and hypertension, lose weight better in a high-fat, low-carb diet, than in a low-fat, high-carb diet,” informs Heimowitz.
One example for her reasoning stems from an abstract conducted by Kevin O'Brien at the University of Washington (Seattle) and presented at the 2002 American Heart Association Scientific Sessions. It suggests that a low-carb diet was more efficacious in causing weight loss and in reducing serum inflammatory markers, than is a calorically matched low-fat diet.”
These results could be seen as evidence benefiting Atkins; however, O'Brien, the author of the AHA-funded study, concludes, “in the study of obese subjects the results are more a function of the amount of weight loss than the type of diet.” He cautions that other studies have suggested diets high in saturated fat and cholesterol are more likely to increase lipids in patients who are either only moderately overweight or lean.
In other words, his results do not let saturated fat off the hook in its implication with many diseases. But it does state a case to eat fewer foods that have high GIs.
Pasta patriots believe that low-carb diets are nutritionally unsound for several reasons but namely because they doubt that science will ever support the claim that saturated fat is not as harmful as some purport. “There are probably 5,000 studies over 30 years which say the opposite,” says Gifford.
Even the creator of the South Beach low-carb diet, Agatston, acknowledged evidence to the contrary of what Atkins purports about saturated fat, writing in 2003 that “…immediately following a meal of saturated fats, there is dysfunction in the arteries, including those that supply the heart muscle with blood.” However, in another AHA study published in the Journal of Endocrinology and Metabolism, Bonnie J. Brehm concluded that over a period of six months, a low-carb diet is not associated with deleterious effects on important cardiovascular risk factors in healthy women.
Nevertheless, the AHA warns that many new studies substantiating low-carb diets do not provide large patient samples or evidence of results over a significant period of time as do reports that uphold opposing views. In response to several studies defending fat and funded by Atkins, the AHA issued a media advisory affirming, “a high intake of saturated fats over time raises great concern about increased cardiovascular risk.”
All Dressed Up with No Carbs to ShowThe Oldways conference presented an impressive scientific consensus but left open no discussion on how food manufacturers can address this problem without losing out to competitors who jump on board the low-carb bus. It has been estimated that over 1,000 low-carbohydrate products found their way to market throughout 2003. This influx of new low-carb products is even concerning Atkins' proponents.
On April 14, 2004, Atkins' representatives warned consumers and manufacturers that low-carb products should not be used as a “dietary short cut. If you're just lowering your carbs with many of the new food products that are now hitting the market, without correctly following a healthy low-carb lifestyle, you could easily get in trouble,” stated a company release. It continued, “…A food can be low in total or net carbs and still be unhealthy. They can include harmful additives and trans-fats and added sugars that offer no nutritional value whatsoever.”
The American Italian Pasta Company (AIPC, Kansas City, Mo.) reported in April that current declines in pasta consumption are accelerating and, as measured by ACNielsen, fell 7% in volume for the first quarter ending March 20, 2004. “AIPC believes that the current pasta market trends are principally the result of low-carb diets and broader carb-consciousness among U.S. consumers,” noted the release. As a result, AIPC has made efforts to expand its partnership with Atkins to create low-carb pasta under the Atkins Quick QuisineTM brand.
Weizhi Chen, vice president of research and development at Barilla America Inc. (Lincolnshire, Ill.), says the company is not going to offer any unproven diets such as low-carb pasta. “If we are in doubt about whether it is good for you, we are not going to give it to you,” Chen says. It is the same reasoning he uses to decide what is best for his children. “Instead of just offering people a choice of what they want, we have an obligation to offer what's right for them,” says Chen.
Barilla's decision not to follow the changing tide stems from their confidence in the Mediterranean Diet, one which is parallel to the American Dietetic Association's (Chicago) criteria, as well as those of many other medical associations. “We try to understand what the consensus is in the scientific community and translate their recommendations into product application,” assures Chen.
Barilla's corporate mission is to help people eat healthier and better, explains Chen. “If you sit down with your grandma and can't explain what this ingredient is and how to use it, then don't use it,” he says, and affirms that Barilla products use wholesome ingredients that are free of chemical additives, preservatives and trans-fatty acids. “That is what differentiates us from our competitors. The challenge is not to make low-carb or whole-wheat pasta, which doesn't taste as good as semolina pasta, but to give people healthy foods that taste great.”
Chen realizes that to help more people eat better and healthier, Barilla will need to create more convenient pasta dishes, but it will be a challenge to present convenient foods that are healthy and taste great at the same time. “I don't want to just give convenience and sacrifice quality,” say Chen.
He also explains that some types of pasta could be less healthy than others. “Semolina is the 'gold' from durum wheat. However, semolina is expensive, and many U.S. pasta makers use durum wheat flour instead or substitute semolina with a percentage of white flour. Doing so will reduce pasta quality and could increase the GI of the pasta. High-quality semolina is not easily metabolized into glucose because it is very “compact and dense,” resulting in a low glycemic index, notes Chen. Chen suggests the solution is not to stop making pasta, or to make low-carb pasta, but to start making pasta that is made from high-quality durum semolina.
Keeping the family name untainted by consumer skepticism is a high priority of those at Barilla, explains Chen. The low-carb fad could plague careless companies in the long run if their customers lose faith in low-carb diets and, subsequently, their products. “Manufacturers have an opportunity to play a role in real health promotion,” says Gifford. “If it's done in a way that says we understand balanced nutrition for good health, manufacturers will win because they will get [consumer] support for it.”