What HbA1c measures
Sugar in your blood sticks to haemoglobin in red blood cells. Because those cells live about 3 months, HbA1c gives an average — unlike a single fasting sugar reading, which can change from day to day.
Some conditions, such as anaemia or certain haemoglobin variants, can make HbA1c less reliable; your doctor will tell you if that applies to you.
Reading the numbers
Below 5.7% is considered normal, 5.7–6.4% is the pre-diabetes range, and 6.5% or more on two tests suggests diabetes.
Your doctor will set a personal target based on your age, other conditions and the risk of low sugars. For many adults that target is under 7%.
Practical ways to lower it
Small, steady changes work well: a daily 30-minute walk, fewer refined carbs and sugary drinks, regular meal times, good sleep, and taking medicines as prescribed.
Recheck every 3 months while you work towards your target — HbA1c changes slowly, so testing more often rarely helps.
When to see a doctor
See a doctor the same day if you notice:
- Sugar readings repeatedly above 300 mg/dL
- Excessive thirst, frequent urination and weight loss
- Shakiness, sweating or confusion that may mean low sugar
- A foot wound that isn’t healing
In an emergency, call 108.
Many of my patients focus on a single fasting sugar reading, which can swing with one late dinner or a bad night’s sleep. HbA1c is steadier, and it is the number I use to judge whether our plan is working. When I set a target with you, I look at your age, other conditions and the risk of low sugars, so two people in the same family may have different goals. If your HbA1c has not moved after three months, that is not a failure — it tells us what to change next. Please bring your home readings to every review.
Frequently asked questions
References
- ICMR Guidelines for Management of Type 2 Diabetes. Indian Council of Medical Research, 2018.
- Use of glycated haemoglobin (HbA1c) in the diagnosis of diabetes mellitus. World Health Organization, 2011.
This article is for general information and isn’t a substitute for medical advice. If you’re worried about your health, see a doctor. In an emergency, call 108.
