People who live with diabetes or have to deal with abnormal glucose levels in their blood often have to monitor their levels and learn about how their body reacts to many triggers or situations. One puzzling experience many of these people go through is “morning highs”, when they learn as they wake up that their blood sugar levels have increased for no apparent reason.
The following information has been elaborated using guidance by the American Diabetes Association exclusively. It does not constitute any form of medical advice and does not intend to replace it, so you should not rely on it and always seek medical attention from your doctor or healthcare provider.
The reasons behind your morning highs
When it comes to morning highs, it can be hard to figure out why you have such readings. These increases may seem counter-intuitive, because you haven’t eaten anything that can directly cause your glucose to run wild. The American Diabetes Association lists a few reasons that may explain why this is happening. We go over them below.
One reason your blood sugar levels might be higher than normal in those early hours is a spike commonly known as the “dawn phenomenon” or “dawn effect”. This is the abnormal increase in glucose many people experience overnight.
As the ADA explains, the phenomenon is caused by certain hormones — cortisol and growth hormone among them — that make your liver increase the glucose production, providing energy so you can wake up. Normally, this process is harmless because it also sees the pancreas release enough insulin to keep this glucose under control.
In the case of people who suffer from diabetes, however, this cannot be achieved, as their bodies might not be able to produce enough insulin or perhaps they are resistant to it. Blood sugar levels are then increased. This phenomenon affects people with both types of diabetes equally, and around 50% of diabetics experience this effect.
Low insulin levels
Low insulin levels overnight may also lead to a rise in blood sugar. Insulin levels may decrease for a number of reasons, depending on each individual. For example, those who use an insulin pump may find that the pump settings aren’t providing enough background insulin —or basal insulin— through the night, or maybe the long-acting dose is also low.
The amount of time insulin lasts is also a factor that could explain why your levels are low in the morning, since injecting long-acting insulin one early in the evening could imply it won’t last into the morning of the following day.
The Somogyi effect — an eponymous term derived from Michael Somogy, the first chemist who described the phenomenon — is a natural reaction of your body against low blood sugar levels, or hypoglycaemia, that occurs overnight.
If your blood sugar levels drop during the night — either because you skipped a meal or you get too much insulin after dinner, for example — the body reacts by producing more glucose, in an attempt to make up for this lack of glucose. This may result in high blood sugar levels the morning after.
How to deal with “morning highs”, according to experts
Waking up to abnormal blood sugar levels can be confusing. If it happens frequently, according to the ADA, it’s important to establish the root of this phenomenon, so you can act accordingly. They recommend:
Keeping track of your blood sugar levels: if these abnormal readings become a pattern, it’s advised to check your levels when you go to bed, then doing it right in the middle of the night and finally first thing in the morning when you’re already awake. For a more comprehensive look at the data, you can use a continuous glucose monitor.
Find the root cause
Bring your data to your doctor so they can better assess what could be happening. Per the ADA, if high blood sugar levels take place at bedtime, it could signal something’s wrong with your meals or medication. If, on the contrary, you seem to be in range at bedtime, this could mean changes to medication are needed. Finally, the dawn phenomenon — a rise between 3 and 8 a.m.— can also be addressed with changes to medication or even an insulin pump.
Exercise might be helpful when trying to curb morning spikes. For instance, taking a stroll after dinner can help you if your insulin levels are waning. However, you should be cautious if exercise is before bedtime, because physical activity lowers blood sugar levels and this may last a few hours, which could make you go low afterwards.
You can also exercise in the mornings, which could be useful to get rid of the extra glucose caused by the dawn phenomenon, or if your levels go very low after exercising in the evenings.
A matter of trial and error
Finally, the ADA points out that it takes time to find a balance that works for you, as every person is different and reaching an equilibrium where you don’t wake to high blood sugar levels and you are also safe from hypoglycaemia as you sleep.
Even if after some time trying you find yourself unable to find an effective strategy, doctors can redefine your thresholds so you can have slightly higher levels in the morning, compensating in some way or making sure you stay in your range the rest of the day. This is why should share your readings with your doctor regularly and follow their advice only to ensure your levels are under control.