Time-in-Range (TIR): The Game-Changing Diabetes Metric You Need to Know

For decades, the A1C test was the gold standard for measuring diabetes control. But in recent years, a revolutionary new metric has emerged that's transforming how we understand and manage diabetes: Time-in-Range, or TIR. This powerful measurement provides insights that A1C simply can't capture, and it's changing lives for people with diabetes worldwide.

Put simply, time in range (TIR) is the percentage of time your glucose stays in your target range, for most adults with diabetes, that's typically 70–180 mg/dL. When people ask "what is a good TIR target?", that's usually what they're talking about.

New to A1C? Read our A1C guide. Curious about carb myths? See Carb Myths. Learn more about Glukee's approach to diabetes management.

What Exactly is Time-in-Range?

Time-in-Range measures the percentage of time your blood glucose levels stay within a healthy target range. Unlike A1C, which gives you an average over months, TIR shows you real-time patterns and helps you understand how lifestyle factors affect your glucose control throughout the day and night.

TIR is typically measured using continuous glucose monitoring (CGM) devices, which provide 24/7 glucose readings. The data reveals not just where your average falls, but how stable your glucose levels are and how much time you spend in different ranges. Understanding TIR targets and how to improve time in range can transform your diabetes management approach.

The TIR Target Ranges: What Should You Aim For?

The standard target range for most people with diabetes is 70-180 mg/dL (3.9-10.0 mmol/L). This range balances the need to avoid hypoglycemia (dangerously low blood sugar) while keeping glucose levels from getting too high.

Current international consensus guidelines recommend these TIR targets:

• At least 70% TIR: Time spent between 70-180 mg/dL (optimal target)
• Less than 4% below range: Time spent below 70 mg/dL (hypoglycemia)
• Less than 25% above range: Time spent above 180 mg/dL (hyperglycemia)

These targets can be adjusted based on your individual circumstances, such as age, diabetes duration, and risk factors for complications.

Why TIR Matters More Than A1C Alone

The revolutionary aspect of TIR is that it reveals glucose variability that A1C completely misses. Two people can have identical A1C levels but dramatically different diabetes experiences:

• Person A: Stable glucose levels throughout the day (high TIR)
• Person B: Frequent spikes and crashes that average out (low TIR)

Research shows that higher TIR correlates with:

• Reduced risk of long-term complications
• Better quality of life
• Lower healthcare costs
• Improved sleep and energy levels

TIR also helps identify specific patterns that need attention, such as post-meal spikes, overnight highs, or unexplained lows. When comparing TIR vs A1C, remember that A1C tells you about long-term averages while TIR shows you day-to-day glucose patterns.

How to Track and Improve Your TIR

Improving your TIR requires understanding what affects your glucose levels and making targeted adjustments. Here's how to get started:

1. Get the Right Tools

TIR requires continuous glucose monitoring. Options include various professional CGM systems and consumer devices available through healthcare providers.

2. Track Everything That Matters

Use an app to correlate your glucose data with:

• Meals and carbohydrate intake
• Physical activity and exercise
• Medications and insulin dosing
• Stress levels and sleep quality
• Alcohol consumption and illness

3. Identify Your Patterns

Look for common TIR challenges:

• Morning highs: Dawn phenomenon or inadequate basal insulin
• Post-meal spikes: Carbohydrate timing or medication adjustments needed
• Overnight lows: Patterns can help you and your care team decide what to adjust
• Exercise-related changes: Blood sugar responses to different activities

4. Make Data-Driven Adjustments

Use your TIR data to optimize:

• Meal timing and composition - When and what you eat
• Insulin dosing - Working with your healthcare provider
• Exercise routines - Timing and intensity adjustments
• Medication regimens - Working with your healthcare provider

Real-World TIR Success Stories

Many people with diabetes have transformed their management by focusing on TIR. For example:

• A person with type 1 diabetes increased TIR from 45% to 75% by adjusting meal timing
• Someone with type 2 diabetes improved TIR from 60% to 85% through consistent exercise
• A person using insulin pumps improved TIR from 55% to 80% by working with their care team

These improvements often lead to better A1C levels, reduced complications, and improved quality of life.

TIR for Different Types of Diabetes

Type 1 Diabetes

For people with type 1, TIR is especially valuable because it helps optimize insulin dosing and timing. Many aim for 70% or higher TIR, with careful attention to hypoglycemia prevention.

Type 2 Diabetes

TIR helps people with type 2 understand how lifestyle factors affect glucose control. It can guide decisions about medication adjustments and help track the effectiveness of dietary changes.

Gestational Diabetes

During pregnancy, TIR targets may be adjusted to ensure fetal safety while avoiding maternal hypoglycemia. Continuous monitoring helps achieve optimal outcomes for both mother and baby.

The Future of TIR and Diabetes Care

As CGM technology becomes more accessible and affordable, TIR is becoming the standard for diabetes management worldwide. Future developments may include:

• Automated insulin delivery systems that optimize TIR
• AI-powered apps that predict and prevent glucose excursions
• Integration with smart devices and wearables
• Population health approaches using aggregated TIR data

Getting Started with TIR Tracking

Ready to start tracking your TIR? Here's your action plan:

1. Discuss with your healthcare provider - Get their guidance on TIR targets and monitoring options
2. Choose a CGM system - Select one that fits your lifestyle and insurance coverage
3. Get an app for tracking - Use tools that correlate TIR with your daily activities
4. Start logging everything - Track meals, exercise, medications, and how they affect your glucose
5. Review and adjust regularly - Use your data to make continuous improvements

Remember, TIR is a tool for empowerment, not perfection. Every percentage point improvement in your TIR represents meaningful progress toward better health.