- Researchers recently examined the effects of a low-carbohydrate diet in people with prediabetes and in people with mild untreated type 2 diabetes (T2D).
- In a randomized clinical trial, participants who cut back on carbohydrates experienced moderate reductions in blood sugar levels, an indicator of diabetes.
- The results of this study are moderated somewhat by various variables beyond the researchers’ control.
The link between carbohydrates and type 2 diabetes (T2D) is well-established, but new research suggests that cutting out carbohydrates can minimize the risk of developing the condition in people prone to the condition. increase.
Recently Published Studies, Randomized Clinical Trials (RCTs)
Kirsten S. Dorrance, lead author and epidemiologist at Tulane University in New Orleans, Louisiana, said: medical news today:
“Although a low-carbohydrate diet is often recommended for people with type 2 diabetes, there is no evidence whether reducing carbohydrates affects blood glucose levels in people with mild or drug-naive prediabetes. This study was conducted in people with blood sugar levels ranging from prediabetic to mild diabetic levels who were not taking diabetes medications.”
Hemoglobin A1C is a widely used clinical term for measuring long-term blood glucose levels.
According to the Diabetes Foundation of America, A1C levels in prediabetics are below 5.7-6.5%. A higher A1C level could mean diabetes.
Dr. Dorans explained that the hemoglobin A1C range of subjects enrolled in this study ranged from 6.0 to 6.9%.
“This range, chosen as the lower bound,
The study recruited 150 adults at an academic center in New Orleans. The six-month trial was conducted from September 2018 to June 2021. Participants ranged in age from her 40s to her 70s and were divided into two groups.
The first group was instructed to reduce their daily carbohydrate intake to less than 40 grams for the first 3 months and to less than 60 grams from the 3rd month until the end of the study.
“We found that hemoglobin A1C decreased over six months with nutritional counseling promoting a low-carbohydrate diet,” says Dr. Dorans.
“In line with previous studies, the low-carbohydrate diet group also lost significant weight compared to the group of people who continued their normal diet.”
At the end of six months, Dr. Dorans and her research team found that A1C levels decreased by 0.23% in the low-carbohydrate group over the normal-diet group.
Very low-carb diets, such as the ketogenic diet, can trigger a metabolic process called ketosis.
However, ketosis does not usually occur on low-carb diets.
According to the study authors, “few participants had detectable urinary ketone bodies, suggesting that ketosis is unlikely to explain the results.”
Still, Dr. Samuel Klein, a professor of cell biology and physiology at the Washington University School of Medicine in St. Louis, who was not involved in the study, expressed concern about study participants meeting their carbohydrate goals. did.
He said MNT The data “indicate poor dietary adherence.”
“It doesn’t matter [study participants] They didn’t cut their carbohydrate intake, but they didn’t meet the goals set. [there] It could have been a bigger change. They must have changed their carbohydrate intake which reduced their caloric intake. It doesn’t look like they were very ketogenic. “
– Dr. Samuel Klein, Professor of Cell Biology and Physiology
The authors note the limitations of this study.
“During follow-up, caloric intake was significantly reduced in the low-carbohydrate diet intervention group, consistent with the significant weight loss observed. No comparisons can be made or the impact on HbA can be determined.1c [hemoglobin A1C] apart from weight loss,” the author writes.
Dr. Klein noted the amount of contact with research interventions that provided guidance in the low-carb group compared to the normal-eating group.
Both groups were provided with a handbook with dietary guidelines and recipes at the start of the study.
To achieve the goal of less than 40 grams of carbohydrates, the carbohydrate reduction group received 4 group sessions and 4 telephone follow-ups every other week, plus individual sessions. There were three group meetings and three phone calls per month for my 60-gram goal.
The regular diet group was offered optional monthly sessions, but otherwise received no guidance beyond the initial handout.
“There were more contacts in the treatment group than in the control group,” said Dr. Klein.
Dr. Jason Ng, Associate Professor of Clinical Medicine at the University of Pittsburgh Medical Center, who was not involved in the study, said: MNT:
“Reducing carbohydrate intake and improving blood sugar levels can be an effective lifestyle treatment for type 2 diabetes. It may or may not affect you, but if you have prediabetes or mild type 2 diabetes, this intervention can lower your blood sugar, even if it doesn’t involve weight loss.”
Dr. Klein says that lowering your carbohydrate intake and increasing your fat intake “tends to increase LDL cholesterol, which wasn’t the case here, but it decreases triglycerides and increases HDL cholesterol.” This is a good thing.”
However, whether a low-carbohydrate diet is harmful to health may actually depend on the individual.
“I don’t think there is good evidence of long-term adverse effects. I know many people are on the Atkins diet, but there have been no reports of real problems,” he said.
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