In 1980, 108 million people were diagnosed with type 2 diabetes. In 2014, the number rose to 422 million . Historically, type 2 diabetes affected only the middle-aged and older population, but today are young adults progressively at risk . The consequences of diabetes can be debilitating and include blindness, kidney failure, heart attacks, and lower limb amputation . Hence, prevention and successful management of type 2 diabetes through dietary and lifestyle changes are a public health priority. As popular diets come and go, this article is going to help to discern science from fiction.
Is A Low-Carbohydrate Or Low-Fat Diet Any Better for type 2 diabetes?
Carbohydrates are broken down into glucose molecules and need insulin to enter the cells.
Understandably, the low-carbohydrate diet gained momentum in the diabetes community, as insulin resistance is a severe problem. The diet is characterised by a maximum intake of 130 grams of carbohydrates per day. Protein and fat intake compensate for the remaining calories .
A consensus report by the American Diabetes Association (ADA) and the European Association for the Study of Diabetes (EASD) states that a low-carbohydrate diet improves glycaemic control substantially in the first six months. However, the positive results diminish at 12 and 24 months . Whether the diminishing effects are due to the intervention itself or the adherence to the diet is yet to be clarified.
The British Diabetic Association (also known as Diabetes UK) advises a low-carbohydrate diet for some people living with type 2 diabetes. It can help with weight loss, glycaemic control and reduce the risk of cardiovascular disease. However, this diet is not superior to the Mediterranean diet, a high protein diet, or a low-glycaemic index diet [5, 6].
Tay et al. investigated a low-carbohydrate and low-fat diet to manage type 2 diabetes. They concluded that both help with weight loss and reduction of HbA1c fasting glucose significantly . HbA1c is a common blood test that measures the average blood sugar level over the past two to three months.
Nonetheless, this randomised control trial found that the low-carbohydrate diet showed greater blood glucose stability, lipid profile improvements, and reductions in diabetes medication requirements than the high-carbohydrate/low-fat approach. It is worth mentioning that the low-carbohydrate diet consists of less than 10% saturated fat and 28% protein .
Do You Need To Follow A Low-Carbohydrate Diet?
Most low-carbohydrate diets double the protein intake, which stimulates insulin secretion and lowers blood glucose, whether people lost weight or not .
Two meta-analyses conclude that a low-carbohydrate diet may be favoured for short-term goals. Yet, their effects seem to diminish after 12 months, and it doesn’t seem to be superior to other dietary approaches, as mentioned before [9, 10].
The good news is that you don’t need to go on a low-carbohydrate diet to manage type 2 diabetes successfully. Nevertheless, the British Diabetic Association and the American Diabetes Association agree that the amount and quality of carbohydrates are critical points to consider [4, 5].
The long-term safety of low-carbohydrate diets for patients with type 2 diabetes has yet to be clarified. Keep in mind that most of these diets fail to be sustainable as most people find it challenging to adhere to this lifestyle. Huntriss et al. found that diets with 130 grams of carbohydrates per day are more realistic than other approaches that advise less than 50 grams .
How Can I Improve My Blood Glucose Levels?
Prioritise whole, unprocessed foods
When choosing a low-carbohydrate diet, make sure the fat comes primarily from foods such as fish, nuts, seeds, olive oil, or avocados. They are rich in unsaturated fats, vitamins, and other micronutrients . Make sure to eat enough non-starchy vegetables (for example broccoli, spinach, asparagus and cabbage) to reach the recommended fibre intake of 30 grams per day .
Improve skeletal muscle tissue with resistance training
Type 2 diabetes decreases the capacity of skeletal muscle to use glucose and fat significantly. The health of muscle tissue is crucial because it is responsible for 80% of insulin-mediated glucose uptake. Through consistent resistance training, a critical amount of muscle mass can be gained and improved. The results are a better uptake and use of glucose and fatty acids, which help losing weight and improving blood glucose levels .
Increase protein intake
Protein intake above the current recommended daily allowance (0.8 grams per kilogram body weight) is advisable for type 2 diabetes patients with normal kidney function. High protein diets (1-2 grams per kilogram of body weight) increase insulin response and reduce HbA1c significantly. Additionally, protein is known to be satiating, preserving muscle tissue, and increasing thermogenesis, a process by which our bodies transform energy into heat instead of storing it .
Reduce the glucose response by consuming starchy carbohydrates after protein and fibre
It can be useful to know that the post-meal glucose and insulin response can be around 40% lower when consuming, for example, a protein-rich steak and fibre-rich asparagus first and followed by starchy potato-wedges last . While this strategy can be helpful, this systematic approach may not appease all! Enjoying and mindfully savouring food is still a more effective approach for long-term health.
This article was written by Dejana Simic BSc and edited by Mei Wan FdSc, BSc (Hons), RD, MBDA, an HCPC Registered Dietitian and Nutritionist.
Dejana obtained a Bachelor of Science in Nutritional Sciences at The University of Vienna and is part of Mei Wan's Nutrition and Health Writer Volunteer Team.
Check out Dejana's article on Veganuary.
Are you confused with what you can and cannot eating with type 2 diabetes? Are you struggling with high glucose levels and want to lose weight? Book your free 15 minute discovery call with Mei to find out how she can help!
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