What are the type 1 diabetes diet plan restrictions and guidelines?
While there are no absolute diet restrictions in type 1 diabetes, healthier food choices can make control a lot easier. For example, meal timing is very important for people with type 1 diabetes. Meals must match insulin doses.
Most people with type 1 diabetes use a long-acting insulin (also called basal insulin or NPH), which means it will continue to lower blood sugar over 24 hours. This means it will lower blood sugar even if there is no glucose from dietary carbohydrates to act upon. Because of this, skipping a meal or eating late puts a person at risk for low blood sugar (hypoglycemia).
On the other hand, eating a larger meal or a meal that contains more carbohydrates that normal will raise blood sugar more than the basal insulin can dispose of. In this situation, a short-acting insulin (also called regular insulin) must be given in the appropriate dose to match the carbohydrate content of the meal and the level of blood glucose before eating.
Eating meals with a low glycemic load (index) makes meal timing easier. Low glycemic load meals raise blood sugar slowly and steadily, leaving plenty of time for the body (or the injected insulin dose) to respond.
People who use continuous glucose monitoring and insulin pumps instead of finger sticks and injecting insulin have a little more flexibility in their meal timing because they have real-time feedback to help them match carbohydrate intake with insulin. However, everyone benefits from becoming more aware of their dietary intake, making diet restrictions to stay consistent with a low glycemic load diet, and matching their meals with appropriate insulin doses.
Paying attention to meal timing and glycemic load enables people with type 1 diabetes to keep their blood glucose levels relatively stable. Stable blood sugar prevents the complications of hypoglycemia and hyperglycemia1. Recent studies have provided contradictory data regarding the benefit of better glycemic control in preventing cardiovascular disease. While we used to think hyperglycemia was worse, the data show increased risk of cardiovascular disease when hypoglycemia is common2. Research tells us that maintaining an overall stable blood sugar (few highs or lows) is best for preventing complications of any kind. Low glycemic load eating and consistent meal timing are the best ways to achieve this.
While some people go overboard with diet restriction, it is also important to consider the nutritional balance (fat, protein, and carbohydrates) in a meal. Specifically, fat, protein, and fiber all slow down the absorption of carbohydrates, and thus allow time for insulin to work, gradually moving glucose out of the blood and into the target tissues. Slower digestion and absorption maintains a more stable blood sugar level.