Low-carb diet sends nearly half of type 2 diabetes patients into remission in small research study

Following a lower carbohydrate diet for an average of 23 months could help achieve a 46% drug-free type 2 diabetes mellitus (T2DM) remission rate in UK primary care, a small practice-based study has suggested.

As part of the study, which took place at the Norwood GP practice in the north of England, trained GPs and practice nurses provided advice on lower carbohydrate diets to registered patients who had newly diagnosed or pre-existing T2DM or prediabetes between 2013 and 2019.

Of the 473 T2DM patients on the practice register, 128 (27%) opted to follow the diet for a mean duration of 23 months. In addition, 71 patients with prediabetes — representing 11% of the 637 people on the practice’s prediabetes register — chose to follow the diet for the same amount of time.

Patients undertaking a lower carbohydrate diet were supported with three one-to-one GP consultations per year, as well as group consultations, which were designed to help the patients understand the consequences of their diet on blood sugar levels.

The researchers’ analysis showed that there were significant improvements in all of the cardiometabolic metrics evaluated — including HbA1c, weight, blood pressure and lipid profiles.

For patients with T2DM, the median weight loss observed was from 99.7kg to 91.4kg after 23 months on the lower carbohydrate diet, and the median HbA1c dropped from 65.5mmol/mol to 48mmol/mol. Patients with prediabetes saw a median decline in HbA1c from 44mmol/mol to 39mmol/mol.

Of the 128 patients on the lower carbohydrate diet, 59 (46%) achieved drug-free T2DM remission, while 93% of patients with prediabetes had attained a normal HbA1c.

“Our audit showed participants who started with the worst blood sugars (HbA1c) saw the greatest improvements in diabetic control,” the study said.

However, the researchers highlighted that the audit only reported results from people who chose to take up the intervention and who persisted with it. In addition, the absence of a control group meant that it was not possible to compare the dietary intervention directly with routine care.

There was also a lack of randomisation, meaning that there was a risk of selection bias.

“Due to the practice-specific nature of this evaluation, there is limited external validity,” the researchers said.

“Still, these results could form the basis for similar service improvement projects in primary care. Similar pilots could be designed to test the validity and cost savings of this approach. At the very least, for patients, clinicians and others affected by T2DM and prediabetes, the results might provide hope of better health outcomes in the future,” they concluded.

Edward Johnston, research communications officer at Diabetes UK, said that weight loss was a the key factor in putting type 2 diabetes into remission but that it was important that anyone looking to lose weight finds a diet that works best for them and that they can stick to, and to approach any change in a safe and sustainable way. 

“It’s important that people considering a low carb option do so with the support of their healthcare team,” he said.

“They will closely monitor any impact on your diabetes management, such as the need to reduce or deprescribe medications to avoid the risk of hypoglycaemia and ensure that you have sufficient fibre and nutrients.”