Practitioners and Health CoachesGlucose EvolutionApril 2026v1.4

CGM Interpretation — Quick Reference

A desk reference for reading a CGM report in a non-diabetic or metabolic health context. Each metric is defined in the key below. References are numbered in square brackets and listed in full at the end.

SBDG

Standard Deviation of Blood Glucose

Shows how much glucose moves up and down across the day. Lower means steadier. Higher means bigger swings.

Fasting glucose

Overnight / morning baseline

Your client’s glucose level before eating, usually judged overnight or first thing in the morning. This gives a simple view of baseline regulation when food is not influencing the picture.

Post-Meal Peak

Post-meal glucose rise

How much glucose rises after meals compared with the pre-meal level. This helps identify meals that are not being handled well.

CV

Coefficient of Variation

A stability check shown as a percentage. It helps compare glucose variability across different clients and across time.

TIR

Time in Range

The percentage of time glucose stays within the target range of 3.9–7.8 mmol/L. Higher is better.

TAR

Time Above Range

The percentage of time glucose is above 7.8 mmol/L. This shows how often glucose is running higher than we want.

TBR

Time Below Range

The percentage of time glucose is below 3.9 mmol/L. This shows how often glucose is dropping lower than expected.

GMI

Glucose Management Indicator

An estimate of what HbA1c may look like based on CGM data. Useful for trends, but it is not the same as a lab HbA1c result.

When reading a CGM report in a non-diabetic or metabolic health setting, start with the metrics that usually show early disruption first. This makes the report easier to interpret and more useful in practice.

SBDG — Look at how steady or “swingy” glucose is across the day. Large swings often show up before the average glucose changes.
Fasting glucose — Check the overnight and morning baseline. This gives a simple read on baseline regulation when food is not influencing the picture.
Post-Meal Peak — Review how high glucose rises after meals compared with the pre-meal level. This helps identify meals that are not being handled well.
CV — Use this as another stability check. It helps compare glucose variability across different clients and across time.
Average sensor glucose — Use this last, as an overall background number rather than the main signal.

Use these as practical working targets for interpreting CGM in non-diabetic clients.

Metric	Working target	What may need attention
SBDG	< 0.9 mmol/L	Higher values suggest less stable glucose control
Fasting glucose	4.5–5.5 mmol/L	≥ 6.1 mmol/L warrants GP follow-up
Post-Meal Peak	Usually 1.5–2.5 mmol/L above pre-meal, with peak < 7.8 mmol/L	Rise > 3.5 mmol/L or peak > 8.5 mmol/L
CV	Typically around 17%	> 25% suggests higher variability
Time in Range (TIR) 3.9–7.8 mmol/L	> 95%	Lower percentages sustained over 14 days may need review
Time Above Range (TAR) > 7.8 mmol/L	Low	> 10% sustained may need attention
Time Below Range (TBR) < 3.9 mmol/L	Minimal	Persistent lows or symptoms warrant follow-up
Average sensor glucose	Typically around 5.4–5.5 mmol/L (5.8 if over 60 years)	Rising trend across time matters more than one isolated number

Practical target: In this guide, a Time in Range above 95% is used as the working benchmark for non-diabetic clients.

These are screening signals, not diagnoses.

Fasting glucose≥ 6.1 mmol/L (Impaired Fasting Glucose) or ≥ 7.0 mmol/L on two separate occasions

Any single sustained reading≥ 11.1 mmol/L

14-day average with symptoms≥ 6.5 mmol/L

Persistent hypoglycaemiaTime Below Range < 3.9 mmol/L exceeding 3% with associated symptoms

Scope of practice: CGM in non-diabetic coaching is a screening tool, not a diagnostic instrument. These thresholds warrant a GP conversation — they do not replace one.

CGM remains the primary tool in this framework because it provides practical, real-world insight into glucose regulation, food responses, and day-to-day metabolic patterns.

Continuous lactate monitoring (CLM) is an emerging area of metabolic monitoring and is not currently available within this system. Several companies are developing this capability, but it is not yet part of standard practice.

As the technology develops, CLM may provide additional context around exercise response, metabolic flexibility, stress physiology, and broader metabolic function. For now, it should be viewed as a future complementary layer rather than a current tool.

In practice: Start with CGM. Focus on glucose interpretation first. CLM may become a useful secondary layer in the coming years, but it is not required for effective practice today.

Glucose Evolution is designed to help practitioners use CGM data more confidently in a non-diabetic or metabolic health context — turning raw data into clearer interpretation, better coaching conversations, and appropriate referral when needed.

Shah VN, DuBose SN, Li Z, et al. Continuous Glucose Monitoring Profiles in Healthy Nondiabetic Participants: A Multicenter Prospective Study. J Clin Endocrinol Metab. 2019;104(10):4356–4364.
Clinical fasting glucose and post-meal glucose thresholds used for referral screening in practice.
Emerging evidence on lactate as an additional metabolic marker.