This article is more than 5 years old. Information may no longer be current.
Low-carb diet healthy start for patients with diabetes
In patients with uncontrolled type 2 diabetes, a diet low in carbohydrates was an effective first approach to improve blood glucose, even without weight loss, according to a recent review.
In contrast to previous studies that have shown inconsistent benefits of low-carbohydrate eating plans for patients with diabetes, the review presented 12 points of evidence showing that low-carbohydrate eating plans could be used to introduce self-management practices for patients with diabetes.
Richard David Feinman, PhD, professor at SUNY Downstate Medical Center, and colleagues suggested in the review that rising rates of both type 1 and type 2 diabetes in the United States point to a need for revised nutritional guidelines.
“The inability of current recommendations to control the epidemic of diabetes, the specific failure of the prevailing low-fat diets to improve obesity, cardiovascular risk or general health and the persistent reports of some serious side effects of commonly prescribed diabetic medications, in combination with the continued success of low-carbohydrate diets in the treatment of diabetes and metabolic syndrome without significant side effects, point to the need for a reappraisal of dietary guidelines,” Feinman and colleagues said in the study.
Barbara Gower, PhD, professor and vice chair for research in the University of Alabama at Birmingham department of nutrition sciences, summarized the data points in a press release. “Diabetes is a disease of carbohydrate intolerance. Reducing carbohydrates is the obvious treatment,” she said.
“It was the standard approach before insulin was discovered and is, in fact, practiced with good results in many institutions. The resistance of government and private health agencies is very hard to understand,” Gower said.
Review and results
The review, published in Nutrition, surveyed long-term randomized controlled trials, including National Health and Nutrition Examination Survey data and the ACCORD trial.
Because no one prescriptive definition for a low-carbohydrate diet exists, the researchers expanded the review’s definition to include a very low-carbohydrate ketogenic diet (<20 g to 50 g carbohydrate daily), a low-carbohydrate diet (<130 g daily), a moderate-carbohydrate diet (26% to 45% of daily calories from carbohydrate), and a high-carbohydrate diet (>45% of daily calories). The American Diabetes Association’s current recommendations are for an adult’s diet to contain 45% to 65% carbohydrates, according to the study.
Among the points of evidence in the review, data demonstrated that carbohydrate restriction was the most effective diet-based strategy to decrease Hb1Ac (compared with low-calorie and/or low-fat diet plans).
Feinman and colleagues also pointed to data that showed recent increases in caloric consumptions among Americans are primarily sourced from carbohydrate-rich foods. From the first NHANES data collected in 1974 to recent NHANES data collected in 2000, men saw a 6.8% increase in kilocalories, broken down into a 23.4% increase in the amount of carbohydrates consumed, a 5% decrease in fat and a 14% decrease in saturated fat. Women saw a 21.7% increase in overall kilocalories, consisting of a 38.4% increase in the amount of carbohydrates consumed, an 11% increase in fat and a 3% increase in saturated fat.
Another point raised by the researchers focused on the benefits of carbohydrate restriction, namely that carbohydrate reduction does not have to result in weight loss for effective glycemic lowering to take place. Previous research showed that a very low-carbohydrate diet resulted in as much as 20% improvement in glycemic lowering.
“Studies in which weight is lost and glycemic control is attained do not show any correlation between the two outcomes,” the study researchers said. “Given the difficulties that most people have in losing weight, this factor alone provides an obvious advantage to low-carbohydrate diets.”
Disclosure: Feinman declared financial associations with Fleishman-Hillard, the Corn Refiners Association and the Veronica and Robert C. Atkins Foundation. Please see the study for a full list of the other researchers’ financial disclosures.