How we approach the management of type 2 diabetes has changed enormously in just the past 5 years. Previously, clinicians took the approach of ‘managing’ the clinical risk factors of diabetes such as elevated glucose and lipids, usually with additional, more potent medications. Some patients might have been advised to try and lose 5-10% of their body weight by eating less fat and reducing portion sizes. However, the idea that you could get people off their diabetes medications completely with diet was rarely mentioned. In fact, when I was working as a dietitian in the UK’s National Health Service back in 2008, I never heard the word ‘remission’ in a conversation about type 2 diabetes.
The huge challenge is helping people to maintain their weight loss.
With the publication of the Diabetes Remission Clinical Trial (DiRECT) in 2017, this all changed. This landmark study showed that an intensive dietary intervention, aiming for a 15-kg maintained weight loss, delivered within primary care could help 46% of people achieve remission of their diabetes. This was defined as a non-diabetic blood glucose level while not having taken diabetes medications for 2 months. Remission was closely linked to weight – 86% of people who lost or maintained more than 15 kg at 1 year achieved remission; reducing to 57% of people who lost and maintained 10 – 15 kg. If people lost 0 – 5 kg, their chance of remission was 7%.
The huge challenge is helping people to maintain their weight loss. With enough weight regain (as little as 3 – 4 kg) people can ‘relapse’ back into type 2 diabetes. Right now, type 2 diabetes remission is based on achieving and maintaining weight loss. What if we could help people lower their blood glucose substantially – below the diabetic threshold – without losing weight? Or, maybe without losing so much weight? This would be much more achievable because losing and maintaining a very large weight loss is extremely difficult.
The solution may be a low-carbohydrate, high-protein diet. A number of studies have been published by different research groups showing that a diet which provides about 20 – 30% of its calories from carbohydrate, and 30% from protein can lower blood glucose in people without type 2 diabetes without weight loss. This is just less than half of the carbohydrate a person usually eats, and about double the protein – the rest is made up of fat. However, we don’t know whether it’s the reduction in carbohydrate or the increase in protein which is responsible for the beneficial effects. This is important to understand so we can give patients the most accurate advice.
I was awarded funding from the Diabetes Research and Wellness Foundation to look at this question. In our current study we are providing a low-carbohydrate diet to volunteers with type 2 diabetes, and then adding in, and removing extra protein in a randomized order. Half of the participants will have 15% of calories from protein for 2 weeks, then 30% for another 2 weeks, and the other half vice versa. We are measuring blood glucose using a continuous glucose monitoring device. We expect to publish the results in late summer 2021.
Similar work is being done by a team in Tennessee who are carrying out the world’s first high-protein remission trial. This will help us understand the longer-term effect of increasing the protein of the diet and reducing carbohydrate on remission of type 2 diabetes. This study will include 30% of calories from protein and 40% from carbohydrate.
Protein is thought to work by helping the beta-cells produce more insulin at mealtimes. The amino acids that make up protein are insulinogenic – meaning they stimulate the production (and release) of insulin. It is known that the amount of amino acids circulating in the blood after a high-protein meal is higher than after a low-protein meal – and the extra amino acids promote a greater insulin response. Adding protein to a meal is known to lower blood glucose in people with and without type 2 diabetes. But whether this works long-term is not known. If it does – this could be exciting for people who want to get remission of type 2 diabetes but can’t lose or don’t want to lose a lot of weight. It’s vital we follow this line of research.
I see many patients who have embarked on an intensive weight loss programme either on their own or on the instruction of a healthcare professional after seeing the news that this could help them come off their diabetes medications. Some of these patients have been very slim to begin with and some were frail afterwards. In fact, some of them came to see me to ask how they could regain weight “without getting diabetes back”. If we could figure out ways to lower blood glucose which don’t rely on lots of weight loss to do it, we could offer these patients a way to put their diabetes into remission while keeping their sense of well-being.