Post Time: 2025-07-18
Managing diabetes effectively involves understanding a range of numbers, from your blood sugar readings to your A1C levels and, increasingly, CGM (Continuous Glucose Monitoring) data. These metrics provide critical insights into your glucose control over different timeframes, allowing you and your healthcare team to make informed decisions about your treatment plan. This article will break down the basics of each of these numbers, explaining what they mean and why they matter for people living with diabetes.
Blood sugar, or blood glucose, is the concentration of glucose present in your bloodstream. This number fluctuates throughout the day, influenced by meals, physical activity, medications, and stress. A fasting blood sugar is typically taken before breakfast and should ideally fall within a target range of 70–130 mg/dL for most adults with diabetes, according to the American Diabetes Association. Postprandial (after meal) glucose targets generally are below 180 mg/dL two hours after starting a meal. Blood glucose monitoring is essential for daily diabetes management, allowing you to adjust your diet and insulin doses as needed. This information is particularly useful in conjunction with your other key numbers, like your A1C and CGM trends, to build a holistic understanding of your control.
Deciphering the A1C: Your Long-Term Glucose Picture
The A1C test is a blood test that provides an average of your blood sugar levels over the past two to three months. Unlike a single blood sugar reading, which only shows what's happening at that specific moment, the A1C paints a broader picture of your glucose management over time. This measure is useful because consistent high blood sugar can lead to complications from diabetes including damage to the kidneys, nerves, eyes, and cardiovascular system. Therefore, maintaining a stable blood sugar range is essential for reducing these risks. A1C reflects the average amount of sugar attached to the hemoglobin in your blood, which directly correlates with your blood glucose levels.
Here’s how A1C levels are generally interpreted:
| A1C Level | Average Blood Sugar (eAG) | Interpretation |
|---|---|---|
| Below 5.7% | Below 117 mg/dL | Normal range (no diabetes) |
| 5.7% - 6.4% | 117 - 139 mg/dL | Prediabetes |
| 6.5% or higher | 140 mg/dL or higher | Diabetes |
Goal: For most adults with diabetes, the target A1C is generally below 7%, according to major diabetes organizations. However, the target can vary depending on your individual health profile. Factors like age, complications, and other health conditions are important. It's important to consult your doctor to determine what your ideal A1C range should be. Furthermore, A1C doesn't highlight blood glucose variability or significant excursions, this is where CGMs shine and become invaluable tools to work together with your blood glucose and A1C data.
Actionable Insights: A high A1C may indicate a need for adjustments to your medication regimen, dietary choices, and exercise routine. Work with your healthcare provider to establish appropriate measures to lower it if it’s above target. Conversely, a too-low A1C (below 6%) can signify the potential of experiencing dangerous lows, and such conditions can also be monitored with CGM data and discussed with your healthcare team.
Leveraging CGMs: Real-Time Insights into Your Glucose
Continuous Glucose Monitoring (CGM) systems have revolutionized diabetes management. These devices provide real-time glucose readings, often updated every few minutes. CGMs consist of a small sensor inserted under the skin, typically in the abdomen or upper arm, that measures glucose levels in interstitial fluid. These systems display readings on a paired smartphone, receiver, or insulin pump. The CGM allows a full picture of blood glucose levels and patterns without having to prick fingers and do manual measurements through fingerstick meters, although sometimes manual checks are needed to ensure CGM accuracy.
Here are key advantages of using a CGM:
- Real-Time Tracking: See how your glucose levels change in response to meals, activity, stress, and medications in real-time.
- Trend Data: Identify patterns and trends in your glucose levels over time, helping you anticipate and manage highs and lows.
- Glucose Variability: Notice fluctuations between highs and lows that traditional blood glucose monitoring and even A1C numbers cannot fully detect. This provides a more nuanced understanding of glucose control.
- Personalized Adjustments: Use the data to make timely adjustments to insulin doses, carbohydrate intake, or exercise routines.
- Alert System: Some CGMs also come with alerts that inform users when glucose goes too low or too high, enabling quick corrective action, and allowing an additional layer of safety.
Understanding CGM Data
A CGM provides you with numbers, but it's more useful to understand the trends. This includes looking at these key aspects:
- Time in Range (TIR): This metric indicates the percentage of time that glucose levels are within the desired target range. For most people, this is between 70–180 mg/dL, and an ideal target of more than 70% is desired.
- Glucose Variability: How much your glucose levels fluctuate throughout the day and from day-to-day. Less variability is usually associated with better long-term health.
- Average Glucose: This should be within your personal target, but needs to be understood in conjunction with both TIR and variability.
Combining the Three
While each of these data points is useful, combining the information provides the greatest insights into how to control blood glucose levels effectively. Your A1C gives you the long term average of your glucose levels, but the blood glucose levels are needed for day to day management and CGM adds even more detail.
For example, an individual might have a good A1C (below 7%), but a CGM can reveal large swings and excursions in glucose levels, and this may require addressing with small but crucial adjustments. Conversely, a person with an elevated A1C may find that consistent small corrections and adjustments shown through the CGM can help lower this A1C metric by achieving consistently good glucose control in the moment.
In summary, the combination of blood glucose monitoring, A1C levels, and CGM insights will allow for proactive management of diabetes, leading to better long-term health and quality of life. Work with your health care team to get access to a CGM and optimize its settings for your individual goals and needs.
In this clip, David Sjostrand, F.N.P. discusses how stress can affect a blood sugar level 269 what to do person’s blood blood sugar 2hr after eating sugar levels. David is whats a fasting blood sugar level a Family Nurse Practitioner practicing at West Valley Medical Group. Learn more about David here: