Glucose & The Energy Rollercoaster
Why stable glucose beats spikes – and what swings do to your body
Everyone’s blood sugar changes throughout the day, but the pattern of those changes is different for different people. Some people experience sharp rises and falls in glucose levels, which are often known as “spikes” and “crashes.” Others have a more stable pattern, with more gradual changes in blood sugar.
Rapid changes in your blood sugar may affect your energy levels, cognitive performance, and even your long-term health.
Volatility vs Stability
A glucose pattern with a lot of volatility looks like a jagged line, with frequent spikes and crashes. These rapid changes in glucose tend to sap your energy and your performance, and if you’re experiencing them on a regular basis, they could affect your health over time.
A healthy glucose pattern still has changes in blood sugar levels, but they’re more like gentle rolling hills instead of mountains.Instead of spiking very high and then crashing very low, glucose levels rise and fall more gradually. This helps to keep your energy levels more stable.
What Happens During a Spike
When blood sugar rapidly increases to a high level, the consequences affect cells throughout the body.
Persistently high blood sugar and erratic patterns can increase oxidative stress in the body. Oxidative stress is an accumulation of free radicals, which are highly reactive molecules that are formed when cells use oxygen to metabolize sugar. Because they’re so reactive, these molecules can cause damage to important components of cells, like DNA and proteins.
Chronically high blood glucose can promote inflammation by activating immune pathways, leading to a heightened immune response. If you experience frequent blood sugar spikes, then your body may enter a state of chronic inflammation, in which the immune system remains constantly activated at a low level.
Both oxidative stress and chronic inflammation are associated with an increased risk of many chronic diseases, including cardiovascular disease, cancer, and dementia.
The Crash and False Hunger
When a high blood sugar spike occurs, the body responds by releasing a large amount of insulin, as it seeks to restore normal glucose levels. This is why, after a spike, blood sugar levels can drop rapidly. In fact, glucose may even drop to a lower level than before the spike, a phenomenon known as reactive hypoglycaemia.
After a high-carb meal or snack, a rapid drop in blood sugar can signal the brain that energy is low. This can trigger the familiar ‘crash’ 1-2 hours later, bringing hunger, sugar cravings, irritability, fatigue, and brain fog
The Long-Term Stakes
Despite all that occurs in the body when blood sugar rises rapidly, research shows that a single glucose spike doesn’t cause lasting damage in healthy individuals.
It’s repeated or frequent spikes over time that can contribute to long-term health risks. When this happens, the body doesn’t have a chance to recover, and the damage starts to add up over time. Repeated spikes in blood sugar can strain the body’s metabolic systems and are linked to an increased risk of health conditions such as type 2 diabetes, heart disease, and fatty liver.
The goal is to reduce the size and frequency of blood sugar spikes.While occasional spikes aren’t usually harmful, frequent or large spikes can strain the body. Ideally, blood sugar should rise and fall gradually throughout the day.”
What You Can Do Today
Rather than constantly checking your glucose levels to see if they’re spiking and crashing, there’s a simple metric you can track on your continuous glucose monitor (CGM) to evaluate overall blood sugar control. It’s called time in range (TIR).
TIR refers to the percentage of time that your blood sugar remains within a healthy range. Levels above this range indicate high spikes, while levels below indicate low dips or ‘crashes.’ A higher TIR reflects more stable blood sugar, with fewer extreme highs and lows over the day.”
For people without diabetes, a blood glucose range of 3.9–7.8 mmol/L is generally used as a guideline for healthy levels. In most cases, the target for TIR should be 90 to 95%, meaning that your blood sugar is within a healthy range almost all of the time.
For those who have diabetes, the top end of the range for blood sugar is often set slightly higher. While high blood sugar is a primary concern, individuals taking insulin or sulfonylureas also face an increased risk of low blood sugar (hypoglycemia) If you have diabetes, your doctor can help you establish a healthy blood sugar range and set a personalized target for your TIR
A higher TIR helps maintain more stable energy, reduces chronic inflammation, and lowers the risk of long-term complications. Having steady blood sugar levels benefits both your immediate and long-term health.
