Prediabetes: Lab Reports, Weight and Daily Habits in One App

HbA1c (also written A1C) reflects your average blood sugar over roughly the past two to three months. Fasting glucose is a morning blood draw after at least eight hours without food; the oral glucose tolerance test (OGTT) checks your level two hours after a sugary drink. The American Diabetes Association (ADA) and the US NIDDK put prediabetes at an A1C of 5.7 to 6.4 percent (39 to 47 mmol/mol), a fasting glucose of 100 to 125 mg/dL (5.6 to 6.9 mmol/L), or an OGTT two-hour value of 140 to 199 mg/dL. Other bodies draw the lines differently: the WHO starts the fasting range only at 110 mg/dL, which Germany's family-medicine society DEGAM and the drug commission of the German Medical Association support, and Germany's national guideline speaks of an increased diabetes risk rather than prediabetes. In the UK, NICE sets its high-risk band at an HbA1c of 42 to 47 mmol/mol (6.0 to 6.4 percent). Whether you have prediabetes is your doctor's call, not Sam's.

Usually not: prediabetes tends to show up first in a blood test. Strong thirst, passing urine more often than usual, tiredness, losing weight without trying, stomach pain or new vision problems such as blurred vision can point to much higher blood sugar. Germany's national guideline says glucose should then be measured without delay: contact your doctor's office straight away; if it is closed, use your local out-of-hours doctor service (NHS 111 in the UK). Don't wait for it to pass. Call your local emergency number (112 in the EU, 999 in the UK, 911 in the US) if you have symptoms of high blood sugar, for example thirst or peeing more, and any of these come with them: feeling or being sick, stomach pain, breathing more deeply or quickly than usual, a faster heartbeat than usual, fruity-smelling breath, or drowsiness or confusion. The same applies if you suddenly cannot see from one or both eyes or have sudden severe eye pain, even if you have never been diagnosed with diabetes. Don't drive yourself. In Sam's symptom diary you can log entries such as 'Excessive thirst' or 'Frequent urination' day by day. A diary entry does not replace seeing a doctor. More in Prediabetes symptoms: why you usually feel nothing.

Prediabetes is not a fixed state, and values can move in either direction. The German diabetes information portal diabinfo.de notes that studies show it can regress. For other people, values stay the same or rise. Both the ADA's Standards and Germany's national type 2 diabetes guideline recommend lifestyle measures for values in this range. Which way yours will go can't be told in advance; repeat tests, which your doctor interprets, show it. Sam has no influence on this and does not replace the lab test.

The ADA's 2026 Standards say people with prediabetes should be checked for diabetes at least once a year, adjusted to individual risk, and NICE in the UK advises a blood test at least yearly for people in its high-risk band. Intervals differ between guidelines: in Germany, for instance, the family-medicine society DEGAM considers a fasting glucose check at the three-yearly health check enough when there is no other sign of diabetes, while the German Diabetes Association and the German Society of Internal Medicine suggest a recheck after three months and then every six months for values in the risk range. With strong thirst or peeing more than usual, don't wait for the next scheduled check: ask your doctor's office to check your blood sugar straight away, out of hours via your local out-of-hours doctor service (NHS 111 in the UK). Your doctor decides what applies to you. If you add each lab report to your Health Vault, Sam compares the last two. If a later test shows type 2 diabetes, the type 2 diabetes page describes what Sam keeps there.

That is a decision for your doctor, case by case. diabinfo.de says medicines usually come into play only once type 2 diabetes is confirmed, and the ADA's Standards say medication may be considered for some adults at high risk, depending on individual factors. If you take medication, the medication list keeps your intake times and reminds you, with no interaction check. Its catalog is a selection, not a recommendation; you set strength and schedule yourself. Don't stop or change anything without talking to your doctor.

There are links, but no simple equation. The ADA's 2026 Standards describe observational studies in which very short or very long sleep and poor sleep quality go along with a higher risk of type 2 diabetes. Diabetes UK explains, for people with diabetes, that stress hormones make insulin work less well and can push blood sugar up, while noting that stress alone doesn't cause diabetes. Sam shows sleep duration, sleep quality and a stress level calculated from heart rate and HRV as trends, as a starting point for a conversation with your doctor.

No. Sam doesn't measure blood sugar, no Apple Watch does so far, and Sam doesn't diagnose. Glucose readings appear only when a meter or sensor saves them to Apple Health and you switch on the Blood Pressure & Glucose group in your health metrics; weight lives in the same group. From lab reports, Sam keeps HbA1c and glucose and shows whether a value sits inside the reference range printed on the report. That is your lab's range, not a statement about whether you have prediabetes. If a value appears in different units on two reports, for example HbA1c once in percent and once in mmol/mol, the comparison of your last two reports in the Health Vault leaves it out. Sam converts no units, so compare values only in the same unit. Why no smartwatch measures glucose is covered in Can Apple Watch measure blood sugar?.

Whatever has built up over the weeks: your lab reports, Sam's comparison of your last two reports, and the monthly report as a PDF with activity, sleep and stress. You can show your medication list in the app. Of your lab reports, the monthly report holds only the count and how many values fell outside the reference range, not the values, and no weight or glucose from Apple Health. In Ask Sam you can ask questions about your own reports; the answers are based on your data and are not medical advice. Sam Chat does not answer questions about weight. What the numbers mean is a conversation for your doctor.