A low-carbohydrate (low-carb) eating pattern reduces the amount of carbohydrate you eat from foods such as bread, rice, pasta, cereals, potatoes, sugary foods, and sweetened beverages. For some people with diabetes, a low-carb eating pattern may help improve blood sugar levels, support weight loss goals, and reduce the need for some medications. Studies show these benefits in the short term. Long-term research has not shown this eating pattern to be better than other eating pattern options.
What is a low-carb eating pattern?
Carbohydrates are important to our health. They provide energy, fibre, vitamins and minerals. A low-carb eating pattern does not mean eating no carbohydrates. Your body still needs carbohydrates for energy and good health.
Health Canada recommends carbohydrates to make up 45-65% of calorie intake. For someone eating 2,000 calories a day, that is about 225 to 325 grams of carbohydrate each day.
A low-carb eating pattern is one that limits the amount of carbohydrate foods to less than 130 grams carbohydrate per day, or about 25-45% of your daily calorie intake. Low-carb eating focuses on:
- Non-starchy vegetables (e.g. broccoli, cabbage, leafy greens, mushrooms)
- Protein foods (e.g. fish, poultry, eggs, legumes, tofu)
- Healthy fats (e.g. nuts, seeds, olive oil, canola oil, avocado)
- Minimizing grains and starches and sugary foods
Possible benefits
Research suggests that low-carb eating can be a good option for some adults with diabetes. Some possible benefits include:
- Improved blood sugar management: Reducing carbohydrate intake can lower blood sugar spikes after meals and improve A1C (average blood glucose over three months). This depends on what and how much you eat and also the type of medications or amount of insulin you take.
- Weight loss: If weight is a concern for you, this eating pattern can support weight loss in the short-term and because of this may improve how well your body uses insulin.
- Reduced need for some diabetes medications: As blood sugar levels improve, some people may require lower doses of diabetes medications, including insulin. Medication changes should be discussed with your healthcare team.
Things to consider
- Low blood sugar (hypoglycemia): People taking insulin or medications that increase insulin production may be at increased risk of low blood sugar if carbohydrate intake is reduced without adjusting medication doses. Speak to your healthcare provider before making any changes.
- Diabetic ketoacidosis (DKA): In some people, a low-carb eating pattern may increase the risk of diabetic ketoacidosis (DKA). People with type 1 diabetes and those taking certain medications (e.g. SGLT2 inhibitors) should speak with their healthcare provider before starting a low-carb eating pattern.
- Lower nutrient and fibre intake: Reducing grains, fruit and dairy can lead to lower fibre intake and missing out on key nutrients you need for good health. Careful meal planning can help prevent this.
- Ability to follow over time: Limiting certain foods makes it hard for some people to eat this way over time.
Key messages
- A low-carb eating pattern is one option for managing diabetes.
- It may help improve blood sugar levels and support weight loss for some people.
- If you take insulin or certain diabetes medications, you may need medication changes when eating fewer carbohydrates.
- Including a variety of foods will help to meet your fibre and nutrient needs.
- Talk with a registered dietitian or healthcare provider before making major changes to your eating pattern.
Sample day of meals
Breakfast: Crustless Apple & Roasted Fennel Quiche + ¾ cup plain Greek yogurt + ½ cup blueberries
Lunch: Tuna Bowl - 1 can (120 g) low-sodium tuna, drained, 2 Tbsp mayonnaise, 1 cup romaine lettuce, 1 serving Four Bean Salad + 3/4 cup mango
Dinner: Korean BBQ Salmon with Asparagus + 1 medium grilled sweet potato drizzled with 2 tsp olive oil