Jury's still out on Atkins vs. low-fat 02/17/04, LESLIE COLE, The Oregonian http://www.oregonlive.com/foodday/o...63973318780.xml Results from a preliminary study at Oregon Health & Science University offer mixed news for disciples of the Atkins diet: If you're counting carbs, you're likely to lose weight without feeling deprived. But some people, especially those prone to heart disease, might be putting themselves at risk. The study, which compared low-carb and low-fat weight-loss regimens, tracked 25 dieters for 18 weeks, then followed up a year later. The results will be used to help launch a larger three- to five-year study of potential health risks under the popular diet, says Diane Stadler, research assistant professor and bionutritionist at OHSU's General Clinical Research Center. Stadler presented the results in late January at two public lectures arranged by the university's Center for Women's Health. Researchers wanted to test several Atkins claims: that calorie for calorie, people lose more weight and more fat on the diet than on other weight-loss regimens, and that it confers a "metabolic advantage," preserving lean muscle tissue as the weight comes off. They also wanted to track blood lipid levels, a key indicator of cardiovascular health. The study compared two groups of dieters ages 25 to 55, averaging 230 pounds. One group followed a low-carb plan modeled on the induction phase of the Atkins diet. The other was put on the low-fat, high-complex-carbohydrate DASH diet (Dietary Approaches to Stop Hypertension), recommended by many physicians for lowering blood pressure and cutting heart-disease risk without medication. Patients in the study ate prepared meals for six weeks, then were asked to follow the same diet at home for another 12 weeks. Here's how the two plans stacked up: Both groups lost about the same amount of weight when consuming the same number of calories, regardless of what they ate. Average weight loss for the Atkins group was 13.5 pounds for first six weeks, while DASH dieters dropped 11.5 pounds on average (no significant difference statistically). Not everyone lost as much as they expected, though. Stadler says some dropped only 3 or 4 pounds on the Atkins plan, indicating that different people respond differently to the diet. Low-carb and low-fat dieters lost the same amount of lean muscle tissue. "The Atkins diet," Stadler says, "doesn't preserve it any more than other diets." DASH dieters, whose cholesterol levels improved as weight came off, scored better on heart-disease risk factors. Cholesterol concentrations for the Atkins group stayed about the same for most participants, and actually worsened in some individuals, which is a concern for people with a family history of heart disease, Stadler says. "You almost expect cholesterol to be reduced when you see that kind of weight loss. We didn't see that." Blood pressure, which started out at normal rates for both groups, didn't change significantly for participants. "But a longer-term, larger study is required to really tease out the effects of this diet," Stadler says. For painless weight loss, the carb counters came out ahead. Atkins dieters were offered more food than they needed and asked to eat until satisfied. With no prompting, they ate just 67 percent of the estimated calories needed to maintain their weight, results Stadler called "impressive." The DASH group was asked to consume the same number of calories sticking with low-fat foods. And averaging 2,100 calories a day, everyone in both groups still lost weight. That's good news for anyone who equates weight loss with starvation. "It's possible to lose weight without depriving yourself," Stadler says. Bigger questions for women on the Atkins diet -- such as does it decrease bone density, and does the high-protein diet lead to kidney damage -- require tracking patients for years. Stadler also wants to know if low-carb dieters can stay slim over the long haul. "The real question is, not just can you make somebody lose weight, but what is the success of that individual keeping that weight off?" Stadler asks. "History tells us that the success is very low." In the meantime, here's her advice for dieters: Low-carb Tell your doctor before starting an Atkins-type diet, get a blood test, and schedule regular checkups while on the diet. Work with a registered dietitian to tweak food choices so they're in line with doctors' recommendations for heart health. For instance, substitute egg beaters for whole eggs, and emphasize lean meats and low-fat dairy products. Take a vitamin and mineral supplement to help prevent cramps, constipation and other possible side effects of low-carb plans. For everyone Focus on portion size. Use low-sodium products whenever possible. Eat more dried fruits (packed with potassium and magnesium, high in fiber), and dark green leafy vegetables, foods known to protect against heart disease. Increase nuts and legumes to two to three servings a day. That alone, Stadler says, is "really a huge step in working toward a heart-healthy diet." "Benefits and Hazards of Ketogenic Low Carbohydrate Diets for Weight Loss—Atkins Njeri Karanja, Principal Investigator Mikel Aickin, Co-Investigator Funding source: National Center for Complementary and Alternative Medicine, through a subcontract with Oregon Health & Science University Study period: May 2001 – March 2003 Research issue: Low-carbohydrate, high-fat, high-protein diets promoted by books, the Internet, and other media are among the most enduring weight-loss diets in the US and Europe. Without an evidence- based understanding of the consequences of these diets, health care providers cannot accurately evaluate these diets to advise patients who wish to use them. Study: The goal of this pilot project was to establish a methodology for studying these diets in a clinical trial setting. Participants with body mass index (BMI) between 27 and 39.9 Kg/m2 were assigned to either a low-carbohydrate diet similar to the one marketed by Dr. Robert Atkins or to an energy-matched, high carbohydrate, low-fat diet similar to the combination diet used in the Dietary Approaches to Stop Hypertension (DASH) study. Participants received all foods and beverages from Oregon Health & Science University during the six-week controlled feeding phase. Follow-up consisted of following these same diets at home for an additional six weeks. Measures of interest included markers of oxidative damage, cardiovascular disease risk (lipids, blood pressure insulin, glucose), bone health, energy expenditure, substrate utilization, and body composition. This study provided us with tools to evaluate how low-carbohydrate weight-loss diets affect adherence, body weight and body composition, energy metabolism, and several markers of chronic diseases that may be affected by the altered nutrient intake. "