Blood sugar measurements
Diabetes mellitus, affectionately known as "sugar disease," is considered one of the most widespread diseases in the developed world. Measuring parameters used to diagnose this disease is therefore part of every general health check-up. There are various approaches to this.
Direct measurement in the blood
The measurement can be taken from either capillary or venous blood, and there are inexpensive devices available for home testing. The test measures the amount of glucose currently present in the blood. Guidelines recommend a fasting blood glucose level of <100 mg/dl (after at least 8 hours of fasting) and <160 mg/dl two hours after a meal. Between these points, even in healthy individuals who are following all dietary guidelines, the level can rise above 200 mg/dl. Personally, I keep my fasting blood glucose below 85 mg/dl and, under normal circumstances, don't want it to rise above 110 mg/dl after a meal.
Measurement of HbA1c - the "long-term blood sugar"
Red blood cells (erythrocytes), or rather the hemoglobin they contain, glycate at a fixed rate, meaning they bind to glucose at a fixed rate. This effect is used in blood glucose measurement to compensate for the significant fluctuations seen in direct measurements. It is assumed that erythrocytes have a fixed lifespan, and the measurement measures what percentage of the hemoglobin is glycated. This measurement thus represents the average glucose level over the lifespan of the erythrocytes. The more glucose was present during this time, the more hemoglobin is glycated. Therefore, a longer or shorter lifespan of the erythrocytes also influences the HbA1c level. More on this elsewhere.
Insulin measurement
When glucose is circulating in the bloodstream, the pancreas releases the hormone insulin. This hormone transports the glucose to the cells, where it is absorbed to be burned for energy in the mitochondria during the respiratory chain. The more glucose in the blood, the more insulin is produced, provided the pancreas is functioning properly. The target value used by my lab is unsuitable for my situation, as shown in the graph: I try to keep my insulin level as low as possible. I will gladly explain the reasons for this later.
Continuous blood glucose monitoring with a CGM sensor
CGM stands for Continuous Glucose Monitoring. This refers to small wearable devices that can be worn on the body for a specific period of time. CGM sensors measure glucose levels in the interstitial fluid at short intervals. This correlates with blood glucose levels, and, simply put, allows for the monitoring of blood glucose trends over time, not only instantaneously but also automatically via a smartphone. The sensors typically remain on the body for about 14 days and then need to be replaced.
