Prediabetes in Women: The Warning You Can Act On
Prediabetes usually has no symptoms, but a simple blood test can pick it up years before type 2 diabetes. Here is what the numbers mean, who is most at risk, and why this is one diagnosis where small changes can turn things around.
TL;DR: Prediabetes means your blood sugar is higher than normal but not yet in the diabetes range: an HbA1c of 42 to 47 mmol/mol (6.0 to 6.4 percent) in the UK, or 5.7 to 6.4 percent in the US. It rarely causes symptoms, so testing is the only way to know. Black African heritage, family history, PCOS and past gestational diabetes all raise your risk, and lifestyle changes cut progression to type 2 diabetes by more than half in a landmark trial.
Prediabetes is one of those results that can leave you unsure how to feel. You do not have diabetes, but you have been told you are heading that way. Some people shrug it off. Others panic and cut out every grain of rice in the house for a fortnight, then give up. The useful middle ground is this: prediabetes is an early warning, and it is one of the few in medicine that comes with strong evidence you can change the outcome.
If you want the background on how blood sugar and insulin affect your hormones, energy and mood, start with our guide to blood sugar and hormones. This post focuses on the next step: what to do once prediabetes is on the table.
What is prediabetes?
Prediabetes means your blood glucose is higher than it should be, but not high enough to be diagnosed as type 2 diabetes. In the UK it is often called non-diabetic hyperglycaemia. Your body is still making insulin, but your cells are not responding to it as well as they should, so sugar lingers in your blood. Left alone, this can progress to type 2 diabetes, which raises the risk of heart disease, stroke, kidney problems and sight loss.
Does prediabetes have symptoms?
Usually not. That is why it is so easy to miss. In the US, the CDC estimates that more than 2 in 5 adults have prediabetes and 8 in 10 of them do not know it. You can feel completely fine and still have a result in the prediabetes range, so if you have risk factors, the test matters more than how you feel.
What do the numbers mean?
The most common test is HbA1c, a blood test that reflects your average blood sugar over roughly the past two to three months. You do not need to fast for it. Different countries report it in different units:
- UK (NICE): an HbA1c of 42 to 47 mmol/mol (6.0 to 6.4 percent) indicates high risk, along with a fasting glucose of 5.5 to 6.9 mmol/l.
- US (American Diabetes Association): prediabetes is an A1C of 5.7 to 6.4 percent, or a fasting glucose of 100 to 125 mg/dL.
- Diabetes range: an HbA1c of 48 mmol/mol (6.5 percent) or above, usually confirmed with a second test.
Labs in Nigeria, Kenya, Ghana and South Africa may report either percent or mmol/mol, so check which unit is on your result before comparing it with anything you read online. A fasting blood glucose test or an oral glucose tolerance test may be used instead.
Who is most at risk?
UK guidance from NICE recommends a diabetes risk assessment for all adults from 40, but from age 25 for people of South Asian, Chinese, African-Caribbean and Black African heritage. That earlier age reflects the higher risk of type 2 diabetes in these communities, which is why NICE wants them assessed 15 years earlier.
The same guidance names conditions that increase risk, including several that matter for women:
- Polycystic ovary syndrome (PCOS). Insulin resistance is common in PCOS, whatever your size. We explain the link in PCOS and insulin resistance.
- A history of gestational diabetes. Diabetes in pregnancy is a strong signal for the future. A large meta-analysis found women who had it were nearly 10 times more likely to develop type 2 diabetes than women who did not. Our guide to gestational diabetes covers what to do after birth.
- Family history. A parent or sibling with type 2 diabetes raises your risk.
- High blood pressure, heart disease or stroke, and carrying extra weight, especially around the waist.
Many of us grew up hearing diabetes described as an "old person's" or "big man's" illness. The UK guidance says otherwise: if you are of Black African heritage, the conversation should start from 25, not 40. Getting tested in your late twenties or thirties is sensible if any of the risks above apply, whether you live in Lagos, Nairobi, Accra or London.
Can prediabetes be reversed?
Often, yes, or at least slowed down substantially. The strongest evidence comes from the US Diabetes Prevention Program, a trial of more than 3,000 adults with raised blood sugar. Over an average of 2.8 years, an intensive lifestyle programme cut the number of people developing type 2 diabetes by 58 percent, compared with 31 percent for the medicine metformin. The lifestyle goals were modest: losing at least 7 percent of body weight and doing at least 150 minutes a week of activity similar to brisk walking.
For a woman weighing 80 kg, 7 percent is about 5.5 kg. That is a slow, doable change, not a crash diet.
What changes help the most?
You do not need a special diet or expensive foods. What helped in the trials, and what fits everyday life:
Move most days. Aim for around 30 minutes of brisk walking five days a week. Walking to the bus stop, taking the stairs, dancing in your living room and a walk after dinner all count. Active muscles use glucose for fuel, so movement of any kind helps.
Build plates around fibre and protein. Fill half your plate with vegetables such as ugu, spinach, sukuma wiki, okra or garden egg. Choose beans, lentils, fish, eggs or chicken for protein. Keep starchy staples like rice, yam, eba or ugali to a smaller portion, and swap white for brown rice or unripe plantain some of the time.
Watch the drinks. Fizzy drinks, malt drinks, sweetened zobo and juice can add a lot of sugar without filling you up. Water, unsweetened tea or zobo without added sugar are better everyday choices.
Protect your sleep and manage stress where you can. Both shape appetite, energy and the habits above, and our weight and hormones guide goes into how hormones play a part.
Do not smoke, and keep alcohol within recommended limits.
In England, people with an HbA1c in the prediabetes range can be referred to the NHS Diabetes Prevention Programme, which Diabetes UK describes as at least nine months of group and one-to-one support on weight, activity and diet. Ask your GP whether you are eligible.
How do I get tested?
In the UK, you can ask your GP for an HbA1c test if you have risk factors. In England, the free NHS Health Check, offered every five years to adults aged 40 to 74 without certain existing conditions, includes a diabetes risk assessment. In Nigeria, Kenya, Ghana and South Africa, HbA1c and fasting glucose tests are widely available at private labs and hospital clinics, though you will usually pay out of pocket. Ask a doctor to help you interpret the result rather than relying on a lab printout alone.
If your result is in the prediabetes range, NICE recommends repeating the blood test at least once a year, so you can see whether the changes you are making are working.
See a doctor promptly if you have symptoms of type 2 diabetes: feeling very tired, peeing more than usual, feeling thirsty all the time, losing weight without trying, blurred vision, cuts that are slow to heal, or itching around the vagina or repeated thrush. These can be signs that blood sugar has already reached the diabetes range.
A note on tracking
Prediabetes changes over months, not days, so patterns help. Asele lets you log symptoms alongside your cycle, which can be useful if you also have PCOS or irregular periods, and the Health Brief gives you a pre-visit summary to bring to your GP. Amara can talk through what an HbA1c result means in plain language, in Yoruba, Hausa, Igbo, Swahili, French or English. You can find us at Asele.
This post is education, not medical advice. Your doctor can look at your full results and history and help you decide on next steps.
References
- National Institute for Health and Care Excellence. Type 2 diabetes: prevention in people at high risk (PH38). nice.org.uk
- American Diabetes Association. Diagnosis. diabetes.org
- Centers for Disease Control and Prevention. Prediabetes: Could It Be You? cdc.gov
- Diabetes Prevention Program Research Group. Reduction in the incidence of type 2 diabetes with lifestyle intervention or metformin. New England Journal of Medicine, 2002. pmc.ncbi.nlm.nih.gov
- Vounzoulaki E, et al. Progression to type 2 diabetes in women with a known history of gestational diabetes: systematic review and meta-analysis. BMJ, 2020. pmc.ncbi.nlm.nih.gov
- Diabetes UK. NHS Diabetes Prevention Programme: what you need to know. diabetes.org.uk
- NHS. Symptoms of type 2 diabetes and how it's diagnosed. nhs.uk
- NHS. NHS Health Check. nhs.uk
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