Summary
Diabetes mellitus is a chronic condition characterized by high blood glucose levels due to the body's inability to produce or effectively use insulin. Managing glucose peaks, or postprandial spikes, is crucial for individuals with diabetes to prevent complications. These peaks occur after eating, and keeping them under control involves monitoring carbohydrate intake, choosing low-glycemic index foods, and adhering to a balanced diet.
Note: this article focuses on type 2 diabetes mellitus.
Diabetes is a disease where glucose is unable to enter cells and help create energy packets called ATP. Think of ATP as tiny batteries used by the little machines working in our cells for various functions. In diabetes, glucose is available in the blood stream. Just not taken up by the cells.
Many pathologies can lead to diabetes mellitus. Most significant is the insulin resistance due to fat accumulation around viscera (visceral fat.) Insulin is the hormone that helps glucose get into a cell. Studies have shown that the fat accumulated under the skin (subcutaneous fat) is less harmful compared to the visceral fat. It is observed that exercise helps prevent accumulation of visceral fat. Japanese wrestlers, for example, have subcutaneous fat instead of visceral fat. This distribution pattern of fat in these wrestlers is due to regular exercise they do.
In diabetics, glucose that is unable to enter into the cells accumulates in the blood and the interstitial fluid. This extra volume of glucose harms various tissues. The most commonly affected structures are kidneys, nerves, eyes, and the blood vessels resulting in kidney failure, nerve damage, blindness, cataract, and heart attacks. Obviously, it is important to prevent glucose accumulation.
Let’s study various food classes and their contribution to the glucose peak. This will help us understand why we should modify our diet to manage diabetes mellitus.
Do carbohydrates cause glucose peak?
100% of carbohydrates absorbed are converted to glucose and released into the blood. Insulin is needed to move this glucose into the cells rapidly. Patients at risk of diabetes or suffering from diabetes should avoid carbohydrates unless there is sufficient insulin added to move the resulting glucose into the cells.
Do proteins cause glucose peak?
In theory, 50% to 60% of proteins should convert to glucose. Glucose peak, however, is not observed after protein consumption. A possible reason for this observation is that the glucose production from protein ingredients is very slow. And, the glucose produced is immediately consumed without causing any remarkable glucose peak. Proteins also do not modify the carbohydrate absorption hence the glucose peak stays at the time expected after a meal.
Do lipids cause glucose peak?
About 10% of the fats convert into glucose. A more important observation is that the lipids delay the glucose peak when combined with carbohydrates by interfering with the absorption of carbohydrates in the intestine. Obviously, the timing of the insulin administration in a diabetic patient will need to be adjusted to align with the glucose peak. The problem is that we cannot predict how delayed will be the glucose peak. Studies have shown that lipids can delay the glucose peak of a night time meal to morning.
Some considerations for patients with type 2 diabetes mellitus
- Carbohydrates are a major source of glucose. Avoid them or combine them with external insulin – if prescribed by your physician.
- Increase proteins in your diet while reducing the carbohydrates.
- Avoid combining fats and carbohydrates in meals.
Click here to watch our video series for the management of type 2 diabetes mellitus.
Disclaimer: this article is not a prescription for any specific patient. It is meant to inform only. The management of diabetes is the responsibility of a patient’s physician in light of the patient’s condition, labs, lifestyle, etc.