Introduction
Although low-carb diets are typically recommended for diabetics and those looking to improve glycemic control, research has repeatedly shown poor adherence to this restriction over a period of several months and a tendency to replace carbohydrates with a high fat intake. To reap the largest glycemic variability benefit (avoiding the largest blood sugar spikes) while maintaining a balanced diet, researchers recommend planning your breakfast as a low-carb meal. On average, breakfast tends to produce the largest blood glucose spike as a result of the carb-rich items often present in a Western breakfast as well as the impaired insulin sensitivity we experience in the early hours of the day from hormonal variations that help us wake up in the morning. Jump down to “The science behind it” to get a deep dive on the research.
How to prevent the spike
Increased fat and protein at breakfast time has been shown to increase satiety and feelings of fullness at lunch and dinner time, which can help people to exercise portion control and avoid overeating.
To reduce the spike only if you’re not insulin resistant and don’t have diabetes:
- Don’t delay breakfast: while you should aim for a lower carb breakfast since insulin resistance is greater in the morning, eating food early in the morning can help release insulin which can lower blood glucose.
An important safety warning:
If you have diabetes, it is important to work to reduce your overall carbohydrate intake in the evenings only with medical supervision. Reducing your intake of carbohydrates can decrease blood glucose as well as lower blood pressure. Consult with a physician to help safely adjust any medications you’re taking so that your blood glucose or blood pressure don’t drop too significantly. Both hypoglycemia (low blood sugar) and hypotension (low blood pressure) can be very dangerous.
The results of the approach
Compared with the high-carb oatmeal breakfast, diabetic participants experienced peak blood levels that were 1.0mmol/L (18 mg/dL) although no statistically-significant change was observed in average 24-hour blood glucose levels.
The science behind it
Research findings suggest that high Glycemic Load (GL) foods consumed in the morning tend to spike blood sugar levels more than when consumed in the afternoon. Here are three key findings that contribute to this understanding:
1) Your Circadian Rhythm: Our bodies have an internal clock known as the circadian rhythm, which influences various physiological processes, including glucose metabolism.
Although the exact underlying mechanisms are still unclear, we know that the hormones that increase when you wake up play a large role.
The hormones that promote glucose release into the blood include:
- Epinephrine: more commonly known as adrenaline or the “fight or flight” hormone, increases blood flow to the muscles
- Cortisol: known as the “stress hormone”
- Glucagon: signals the liver to release glucose into the blood
- Growth Hormone: repair and regeneration
2) Elevated Cortisol Levels:Cortisol, a hormone involved in stress response, follows a diurnal pattern with higher levels in the morning. Cortisol has been found to interact with insulin and influence glucose regulation. Elevated cortisol levels in the morning can contribute to impaired insulin action, leading to increased blood sugar response when consuming high GL foods.
3) Overnight Fasting and Liver Glycogen Stores: During the overnight fast, the body’s glycogen stores, primarily located in the liver, become depleted. When high GL foods are consumed in the morning after an extended period of fasting, there is limited glycogen available for glucose storage. As a result, the consumed carbohydrates are more readily converted into glucose and released into the bloodstream, leading to a more pronounced spike in blood sugar levels.
Taken together, the combination of reduced insulin sensitivity in the morning, elevated cortisol levels, and depleted liver glycogen stores contribute to the observation that high GL foods consumed in the morning tend to result in a higher blood sugar spike compared to when consumed in the afternoon. These findings highlight the importance of considering meal timing and glycemic load when managing blood sugar levels throughout the day.
Insulin is the most well-known hormone impacting blood sugar. When blood glucose rises, insulin is released and helps move glucose out of the blood and into cells for immediate energy use or storage.
How it worked for me
As a person without insulin resistance, I wanted to compare the effect on my blood sugar levels from the same bowl of oatmeal in the afternoon instead of the morning.
For patients with diabetes
People who take insulin may alsoexperience a spike in blood sugar in the morning, but for a different reason. If you manage your diabetes with insulin, you may experience something called the Somogyi Effect if you skip a meal or snack before bed or take too much or too little insulin at night. This occurs when your blood glucose lowers overnight, and then “rebounds” in the morning.
The Somogyi effect is generally considered to result from inconsistencies or inadequate diabetes management. Consult your doctor to determine if you’re experiencing the Somogyi effect andneed adjustments to your schedule or the dawn phenomenon. As a general rule, ifyour blood sugar is low around 2-3 AM, you’re likely experiencing the Somogyi effect. If it’s normal or high at this time, the morning spike will oftenresult from the dawn phenomenon.
If you have type 2 diabetes and take only certain diabetes medications like metformin, you should not experience the Somogyi effect.