Beyond the Numbers: Understanding Your Body’s Real Glucose Story
I’ve never been a biohacker, and I’m not someone who chases wellness trends. But after reading Glucose Goddess by Jessie Inchauspé, I became curious about what I might learn from wearing a continuous glucose monitor (CGM). Not to optimize anything — simply to observe how my body responds to food and stress during an ordinary day.
Most mornings begin with coffee. Many include a workout. The day moves through my full-time job and ends with my functional nutrition practice.
I watched a short tutorial, applied the sensor, opened the app, and wore the CGM for a couple of weeks while going about my life.
I learned a great deal. I also came to understand what these devices cannot show.
A Simple Reminder About Glucose and Insulin
Wearing a CGM reinforced something I remind clients of often: glucose is not the enemy. It is fuel. It comes from food, but it also comes from hormones, stored energy, and stress.
From an evolutionary standpoint, glucose was never meant to remain perfectly flat. It rises and falls in response to movement, food availability, stress, and environmental demand. Temporary rises once helped humans hunt, escape danger, and survive uncertain conditions. The issue is not glucose itself — it is when modern life keeps those survival signals switched on all the time.
For millions of years, our cravings and digestive systems were balanced because sugar was rare… Apart from honey, most foods our hunter-gatherer ancestors ate were no sweeter than a carrot. It was not until very recently that technology made pure sugar abundant.
— Daniel Lieberman, evolutionary biologist, Harvard University
That shift matters because insulin evolved to manage intermittent demand, not constant exposure.
Insulin helps move glucose from the bloodstream into cells where it can be used. What stood out most during my CGM experiment was how much insulin work may be happening behind the scenes even when glucose readings look completely normal — with no obvious signal that this effort is occurring.
What a CGM Does Well
A CGM offers a real-time window into daily patterns. Meals, movement, sleep, and stress all leave a trace. Over time, predictable routines become easier to recognize, and disruptive ones harder to ignore.
As Inchauspé explains, eating fiber, protein, fat, and starch in a specific order can reduce the overall glucose rise by roughly 73 percent and the insulin response by 48 percent.
In everyday life, the effects usually feel less dramatic:
• fewer energy dips
• less urgency around food
• steadier focus
Simple shifts — eating fiber first, avoiding carbohydrates on their own, choosing a savory breakfast, or adding brief movement after meals — often help the body handle glucose more smoothly. These strategies can be useful whether someone wears a CGM or never uses one.
Most foods do not need to be eliminated unless there is a clear health reason. When quality is low or timing is off, the body simply has to work harder to manage them.
The Limits: What a CGM Cannot Show
A CGM measures glucose in the fluid surrounding cells. It does not measure insulin.
It cannot show how hard the body may be working to keep glucose within a normal range — or whether the system is under strain before numbers change at all.
This helps explain why someone can feel tired, hungry, wired, or mentally foggy even when CGM readings look fine. The device captures surface data. The body reflects what is happening underneath.
This became especially clear after a friend mentioned her CGM showed a rise after drinking room-temperature lemon water.
Lemon water contains very little sugar. The juice of half a lemon provides roughly 0.5 to 1 gram — less than a quarter teaspoon.
When glucose rises after lemon water, sugar is rarely the cause. The response is more often tied to acidity, being fasted, dehydration, or a nervous system already under strain. In these situations, stress hormones such as cortisol can signal the liver to release glucose into the bloodstream. The CGM records the rise; it does not explain why it happened.
I saw similar patterns on my own CGM during stressful periods, even when food stayed the same.
| CGM Shows | CGM Doesn’t Show |
|---|---|
| How your glucose rises and falls throughout the day | Whether your insulin is high even when glucose looks normal |
| Your response to specific meals | Whether glucose is high because insulin hasn’t kicked in yet |
| How stress, sleep, caffeine, movement, and timing affect your numbers | How hard your body is working behind the scenes to keep glucose stable |
| Whether a meal keeps you steady or spiky | Early signs of insulin strain that show up as cravings, fatigue, or 2–4 a.m. waking |
| How fast your glucose changes | Your hormonal landscape |
| Your overnight glucose rhythm | The quality of your digestion or absorption, or how your gut–brain axis is reacting |
| The shape of your glucose curve | How your nervous system is influencing your metabolic response |
Spikes Do Not Always Mean Trouble
What matters is not whether glucose rises, but whether the body returns to baseline smoothly — and how you feel afterward.
One of the most useful ideas Inchauspé shares is that the goal is not a flat line. Occasional rises are normal. The body handles gradual increases and steady declines far better than sharp peaks followed by crashes. What matters is how your body responds — does it return smoothly, or do you crash? These responses offer important clues.
Not every rise is driven by insulin. Glucose can increase in response to stress, cold exposure, certain workouts, poor sleep, hormonal shifts, or even excitement. A spike reflects a moment; it does not define a pattern.
Insulin-related challenges often appear first in how the body feels. Numbers usually lag behind.
The Pattern CGMs Miss Most Often
There is a stage — common in women, busy parents, and anyone living with chronic stress — where glucose remains relatively stable because insulin is compensating behind the scenes.
A CGM cannot detect this compensation. But, the body often can.
Common signs include:
• cravings or shakiness between meals
• afternoon energy dips
• waking between 2:00 and 4:00 a.m.
• brain fog after eating
• inflammation after sugar
• feeling tired but overstimulated
• difficulty feeling satisfied after meals
By the time numbers change, many people have been compensating for months.
How Insulin Is Measured
Insulin cannot be measured by a CGM. It must be evaluated through blood testing — most commonly fasting insulin after an overnight fast, or post-meal insulin to assess response.
I don’t order labs, and I encourage people to work with a functional medicine physician or trusted provider. Still, understanding how insulin is measured helps explain why glucose and insulin do not always move together.
Habits That Support the Body — With or Without a CGM
Supporting steadier energy and smoother glucose responses does not require a complete dietary overhaul. Small, intentional adjustments often make the greatest difference.
Many of the principles Inchauspé teaches — and those I share with clients — come down to timing and food combinations:
• eat fiber or vegetables first
• add protein and healthy fats before starches or sweets
• begin meals with greens when possible
• choose a savory, protein-rich breakfast
• pair carbohydrates with fat and protein rather than eating them alone
• move after meals, even briefly
• enjoy dessert as part of a meal rather than on its own
• remember that all sugars behave similarly in the body
• consider a small amount of diluted apple cider vinegar before meals if it agrees with you
The Synergy Perspective
A CGM can be a helpful guide, but it is only one lens.
Hunger, energy, sleep quality, focus, and how the body feels day to day tell the most reliable story. When those signals stabilize, the numbers usually follow.
