The study found that the participants’ average hemoglobin A1C a long-term barometer of blood sugar levels, fell to just 5.67 percent. An A1C under 5.7 is considered normal, and it is well below the threshold for diabetes, which is 6.5 percent.
“Their blood sugar control seemed almost too good to be true,” said Belinda Lennerz, the lead author of the study and an instructor in the division of pediatric endocrinology at Boston Children’s Hospital and Harvard Medical School. “It’s nothing we typically see in the clinic for Type 1 diabetes.”
The new study comes with an important caveat. It was an observational study, not a randomized trial with a control group. The researchers recruited 316 people, 130 of them children whose parents gave consent, from a Facebook group dedicated to low-carb diets for diabetes, called TypeOneGrit, then reviewed their medical records and contacted their medical providers.
While it was not a clinical trial, the study is striking because it highlights a community of patients who have been “extraordinarily successful” at controlling their diabetes with a very low-carb diet, said Dr. David M. Harlan, the co-director of the Diabetes Center of Excellence at the UMass Memorial Medical Center, who was not involved in the study. “Perhaps the surprise is that for this large number of patients it is much safer than many experts would have suggested.”
“I’m excited to see this paper,” Dr. Harlan added. . “It should reopen the discussion about whether this is something we should be offering our patients as a therapeutic approach.”
The authors of the paper cautioned that the findings should not lead patients to alter their diabetes management without consulting their doctors, and that large clinical trials will be necessary to determine whether this approach should be used more widely.
“We think the findings point the way to a potentially exciting new treatment option,” said Dr. David Ludwig, a co-author of the study and a pediatric endocrinologist at Boston Children’s Hospital who has written popular books about low-carb diets. “However, because our study was observational, the results should not, by themselves, justify a change in diabetes management.”