An A1C between 5.7% and 6.4% means prediabetes. It usually causes no symptoms at all, roughly one in three American adults has it, and the large majority do not know. It is also the single most reversible serious diagnosis in medicine — in the landmark Diabetes Prevention Program trial, modest weight loss plus regular activity cut progression to type 2 diabetes by around 58%, and by about 71% in people over 60.
That is the whole reason to get tested while you feel fine.
The numbers
| Test | Normal | Prediabetes | Diabetes |
|---|---|---|---|
| A1C (3-month average) | Below 5.7% | 5.7 – 6.4% | 6.5% or above |
| Fasting glucose | Below 100 mg/dL | 100 – 125 mg/dL | 126 mg/dL or above |
| 2-hour glucose tolerance | Below 140 mg/dL | 140 – 199 mg/dL | 200 mg/dL or above |
A1C is usually the most practical test because it needs no fasting and reflects the previous two to three months rather than one morning.
Who should be tested
Screening is recommended for all adults from age 35, and earlier if you have any of: overweight or obesity, a parent or sibling with diabetes, physical inactivity, high blood pressure, abnormal cholesterol, polycystic ovary syndrome, a history of gestational diabetes or a baby over 9lb, or a history of cardiovascular disease. Risk is also higher in people of African American, Hispanic/Latino, Native American, Asian American, and Pacific Islander descent.
If your result is normal, repeat roughly every three years. If it shows prediabetes, annually.
Symptoms — and why waiting for them is a mistake
Prediabetes typically has none. Type 2 diabetes often develops so gradually that people normalise the symptoms for years:
- Increased thirst and urinating more, especially at night
- Fatigue
- Blurred vision
- Slow-healing cuts, or frequent infections
- Tingling or numbness in the hands or feet
- Unexplained weight loss
- Recurrent thrush or urinary infections
By the time these are obvious, complications have often already begun. Roughly a third of people with type 2 diabetes at diagnosis already have some degree of nerve, kidney, or eye damage — which is the argument for screening rather than waiting.
Two symptom patterns need same-day attention: very high blood sugar with vomiting, abdominal pain, drowsiness, or fruity-smelling breath (possible ketoacidosis — a genuine emergency), and blood sugar that is too low, causing shaking, sweating, confusion, or loss of consciousness.
What actually reverses prediabetes
The trial evidence is unusually clear here, and it is not exotic.
Lose about 7% of your body weight, if you carry excess. For someone at 200lb that is roughly 14lb. Not a transformation — a meaningful, achievable shift.
Move 150 minutes a week. Brisk walking counts. Muscle-strengthening twice a week adds further benefit, because muscle is where glucose gets used.
Change what carbohydrate you eat, more than how much. Whole grains, beans, vegetables, and fruit behave very differently from white bread, sugary drinks, and pastries. Sugary drinks are the easiest single win for most people.
Sleep properly. Short sleep and untreated sleep apnoea both worsen insulin resistance measurably.
Consider medication. Metformin is sometimes recommended alongside lifestyle change, particularly for people under 60, those with a BMI over 35, or women with previous gestational diabetes. Worth discussing.
Structured Diabetes Prevention Programs exist, are often covered by insurance including Medicare, and produce better results than going it alone. Ask us about referral.
If you already have diabetes
Management is about protecting your eyes, kidneys, nerves, heart, and feet — and it works. A realistic routine:
- A1C every three to six months, with a target set individually with us
- Blood pressure at every visit — controlling it matters at least as much as controlling sugar
- Cholesterol managed, usually with a statin
- Annual dilated eye examination — diabetic retinopathy is silent until it is not
- Annual kidney tests (urine albumin and blood creatinine)
- Foot check at every visit, and your own check daily. Numb feet mean an injury goes unnoticed until it is infected.
- Vaccinations kept current, including influenza, COVID-19, and pneumococcal
- Dental care, because gum disease and blood sugar worsen each other
Newer medication classes — GLP-1 receptor agonists and SGLT2 inhibitors — do more than lower glucose; several have demonstrated cardiovascular and kidney benefits. If you have not reviewed your regimen in a few years, it is worth doing.
The Arizona part
Heat and dehydration raise blood sugar by concentrating the blood, and high blood sugar itself causes fluid loss — a loop that a summer here accelerates. Drink deliberately.
SGLT2 inhibitors increase urination, so the dehydration risk in extreme heat is real and worth planning around.
Check your feet religiously if you walk barefoot on hot surfaces. Pavement and pool decks here reach temperatures that cause burns, and neuropathy means you may not feel it happening. We see this every summer, and it is entirely preventable.
Store insulin properly. Heat degrades it, and a car in July will ruin a vial in an afternoon.
Where to go
Book our Medical Clinic for an A1C, a risk assessment, or a proper review of diabetes you already have. Blood work is run in this building, so results usually come back the same day. Call (602) 671-7981.
Come to our Emergency Room — open 24 hours — for vomiting with high blood sugar, confusion, drowsiness, a severe low, or a foot wound that looks infected. ER: (602) 671-7990.
Related: heart health · when nausea and vomiting become an emergency
Sources
- CDC — Prediabetes: your chance to prevent type 2 diabetes
- NIH / NIDDK — Diabetes Prevention Program outcomes
- American Diabetes Association — Standards of care
- US Preventive Services Task Force — Prediabetes and type 2 diabetes screening