Type 2 Diabetes and Plant-Based Diets

Did you know that one in three Canadians is living with diabetes or prediabetes? That’s close to 11 million people.¹ Of people living with diabetes, 90-95% live with type 2 diabetes.²

When it comes to the management of type 2 diabetes, diet and lifestyle play a major role in its prevention and treatment.

Several studies show that a plant-based diet is effective in both reducing the risk of developing type 2 diabetes, as well as in management of the disease.^3,4,5 As the name suggests, a plant-based diet focuses on foods that come from plants. It typically includes whole grains, fruits, vegetables, pulses (like beans and lentils), nuts, seeds, and plant-based oils (like canola, avocado, and olive oil). While some plant-based diets eliminate meat, fish, dairy, and eggs, many plant-based diets include these foods in small amounts.

How Do Plant-Based Diets Impact Diabetes?

There are several mechanisms by which a plant-based diet is thought to improve management of diabetes and glycemic control. First, plant-based diets are high in fibre and antioxidants like polyphenols. Studies have shown that both nutrients can improve insulin sensitivity.³

Fibre is a particularly important nutrient when it comes to diabetes and blood sugar management. Since fibre is digested slowly, it can prevent sharp rises in blood sugar after a meal. Diets high in soluble fibre have been shown to improve post-meal blood sugars, as well as long-term blood sugar management. In addition, several prospective studies have shown that a higher-fibre diet is associated with lower levels of inflammation. Since inflammation is an important risk factor for the development of type 2 diabetes, a reduction in inflammation may be protective against developing type 2 diabetes.⁴

In addition to containing important nutrients that improve insulin sensitivity, plant-based diets also tend to be low in compounds associated with insulin resistance. This includes saturated fat, advanced glycation end products and nitrosamines. Saturated fat (which is found primarily in animal-based foods) may impair insulin signaling and decrease glucose uptake, thereby raising blood sugars. Advanced glycation end products have been implicated in the development of type 2 diabetes, and nitrosamines have been shown to generate pro-inflammatory molecules, which may contribute to the development of insulin resistance.³ Since a plant-based diet is typically low in these compounds, following one may be important for the prevention of type 2 diabetes.

What does this mean for the treatment and prevention of type 2 diabetes? Several studies have shown that a plant-based diet is effective in reducing type 2 diabetes risk and improving glycemic control. A study of 6798 participants in the Netherlands showed that eating a plant-based diet was associated with lower insulin resistance, lower prediabetes risk, and lower type 2 diabetes risk.⁵ Another study showed the importance of overall diet quality on type 2 diabetes risk. A meta-analysis that analyzed data from three studies following over 200,000 participants showed that a diet high in plant foods and low in animal foods was associated with a reduction of about 20% in the risk of type 2 diabetes.⁴

Diabetes and Heart Health

In addition to aiding with blood sugar management, a plant-based diet can also protect against the cardiovascular risk factors associated with diabetes.

People with type 2 diabetes are over three times more likely to be hospitalized with cardiovascular disease.² Type 2 diabetes increases the risk of high blood pressure, atherosclerosis, coronary artery disease and stroke.⁶

Plant-based diets have been shown to reduce cardiovascular disease risk factors. This includes lowering of LDL cholesterol. This is primarily achieved by reducing the amount of dietary saturated fat (which is predominantly found in animal foods) and replacing it with heart-healthy, plant-based mono- or polyunsaturated fats. Studies have also shown that an increase in dietary fibre is associated with a lower risk of cardiovascular disease. In particular, soluble fibre has been shown to decrease total serum cholesterol and LDL cholesterol levels.⁷

Take-Home Message

A large body of evidence shows that a plant-based diet is effective for both the prevention and treatment of type 2 diabetes. Additionally, a plant-based diet has been shown to reduce cardiovascular disease risk factors associated with type 2 diabetes. Luckily, plant-based eating doesn’t need to be complicated. Check out our guide, “Plant-Based Meals for People with Type 2 Diabetes” to get started.