In the past, people with diabetes had to rely on finger prick blood tests several times a day in order to test their blood sugar and adjust their eating, exercise, and more. Now, continuous glucose monitors (CGMs) have emerged as a way for people to receive immediate feedback about their blood sugar levels and how different habits or choices affect those levels. Here, learn more about CGMs, why you might use one, and innovative ways to optimize your performance and quality of life using a CGM.
What Is a CGM?
A CGM is a device used to monitor glucose on an ongoing basis and provide results in real time. It works by embedding a small sensor under your skin (usually in your abdomen or arm) and using an adhesive patch to hold the sensor in place. Then, the sensor transmits information and readings to a monitor device (such as a handheld monitor or a phone app) continuously, eliminating the need for frequent finger prick blood tests. Many CGMs also have the ability to alert the wearer when blood sugar levels get too high or too low, allowing the user to take immediate action to regulate their blood sugar. They are usually worn for 30 or 60 days.
The most common reason to use a CGM is to manage diabetes and keep blood sugar levels within your recommended range. You might also use a CGM if you’re at risk of developing diabetes, particularly type 2 (adult onset) diabetes. Type 2 diabetes often develops as a result of insulin resistance; being overweight and inactive are risk factors for type 2 diabetes. By using a CGM (even if you don’t have diabetes), you can better understand how various activities and habits impact your blood sugar levels — and take preventative steps to manage your blood sugar proactively.
Ideal Levels and What to Look For When Wearing a CGM
Biologically, everyone is different — and so everyone’s ideal blood sugar levels will vary slightly. However, the general recommendation is to keep levels below 140 mg/dl, with under 120 as the ideal. Within 2 hours after a meal, men should aim for 78 mg/dl, and women should aim for 81 mg/dl. In healthy individuals, the primary goal of wearing a CGM is to figure out which foods cause the most spikes and for how long.
When wearing a CGM, make sure to notice your fasting glucose: Your fasting glucose is your blood sugar level when you first wake up; these are typically higher in the morning due to elevated cortisol levels. You might also be impacted by CRY2, a genetic SNP. A healthy fasting blood sugar in people without diabetes ranges from 70-90 mg/dl.
Also, check your blood sugar levels before, during, and after meals to see how your body is responding to your food and drink intake. Post-prandial (post-meal) glucose values are important, not only for how high they get but also for how long they stay elevated. The goal is for them to return to 70-90 mg/dl within 2 hours of a meal.
Activities That Can Impact Glucose Levels
Several everyday activities can impact your blood glucose levels. For example:
- Movement: Staying active throughout the day (especially walking 10-15 minutes before or after meals) is one of the best ways to manage blood sugar levels. Strength training also helps manage glucose levels as muscles are the largest glucose storage spaces.
- Diet: Include protein and/or fiber with carbs to slow absorption and reduce blood sugar levels.
- Fasting: Most people will notice a drop in blood sugar, especially during extended fasts. Some express concern that hypoglycemia (low blood sugar) may cause damage or injury. If you experience lightheadedness or feel off then lay down and wait it out. If this continues, just eat something. We don’t want you to feel uncomfortable.
- Sleep: Sleep loss, sleep changes, travel, and circadian rhythm alterations may negatively affect levels while optimizing sleep will positively affect glucose levels.
- Stress: Stress may increase glucose levels as counterregulatory hormones like noradrenaline and cortisol lead to gluconeogenesis in the liver and increase blood sugar levels in the body.
- Supplements: Berberine, alpha lipoic acid, resveratrol, fish oil, green tea, and ceylon cinnamon have been shown to positively impact blood sugar levels.