Porter Health
Understanding Prediabetes & Diabetes
A Patient's Guide to Prevention and Management
Think of insulin as a "key" that unlocks your cells to let sugar (glucose) from your food enter and provide energy. Insulin resistance is when your cells stop responding well to this key, so your pancreas has to make more and more insulin to keep blood sugar normal.
The Progression:
Normal → Insulin Resistance
Cells become resistant, pancreas compensates by making extra insulin. Blood sugar still normal, but insulin levels are high.
Insulin Resistance → Prediabetes
Pancreas can't keep up anymore. Blood sugar starts rising above normal but not yet in diabetes range.
Prediabetes → Type 2 Diabetes
Pancreas becomes exhausted. Blood sugar rises into diabetes range, causing damage to blood vessels, nerves, kidneys, eyes, and heart.
The Good News: Prediabetes is reversible! With lifestyle changes, you can prevent or delay type 2 diabetes by up to 58% (71% if you're over 60).
Three tests can diagnose prediabetes or diabetes. Your doctor may use one or more of these:
HbA1c (Hemoglobin A1c or "A1C")
Measured in percentage (%)
What It Measures:
Your average blood sugar over the past 2-3 months. It measures how much sugar is stuck to your red blood cells. Think of it like a "report card" for your blood sugar control.
Why It's Useful:
No fasting required, reflects long-term control, not affected by what you ate yesterday.
Standard Diagnostic Criteria:
Important for South Asian and High-Risk Populations:
If you are of South Asian ancestry or have other high-risk factors (family history, obesity, PCOS, gestational diabetes), even an HbA1c of 5.4% or 5.5% may be concerning.
Why?
- South Asians develop diabetes at lower BMI and younger ages
- Higher rates of insulin resistance even at "normal" HbA1c levels
- Increased visceral (belly) fat that isn't captured by standard BMI
- Greater cardiovascular risk at lower HbA1c thresholds
Action: If your HbA1c is 5.4-5.6% and you're high-risk, talk to your Porter Health coach about aggressive lifestyle intervention to prevent progression.
Fasting Plasma Glucose (FPG)
Measured in mg/dL
What It Measures:
Your blood sugar after fasting for at least 8 hours (usually overnight). Shows how well your body controls blood sugar when you're not eating.
Diagnostic Criteria:
Oral Glucose Tolerance Test (OGTT)
2-hour test, measured in mg/dL
What It Measures:
How your body handles a sugar load. You drink a sweet liquid (75g glucose), then blood sugar is checked 2 hours later. This test is most sensitive for detecting prediabetes.
Diagnostic Criteria (2-hour value):
The ADA recommends testing for all adults starting at age 35, or earlier if you have risk factors:
Overweight/Obesity
BMI ≥ 25 (≥ 23 for Asian Americans)
Family History
Parent or sibling with diabetes
High-Risk Ethnicity
South Asian, African American, Latino, Native American, Pacific Islander
Physical Inactivity
Sedentary lifestyle
History of Gestational Diabetes
Diabetes during pregnancy
PCOS
Polycystic ovary syndrome
High Blood Pressure
≥ 140/90 mmHg or on BP medication
Abnormal Cholesterol
HDL < 35 mg/dL or triglycerides > 250 mg/dL
Cardiovascular Disease
History of heart disease or stroke
The Diabetes Prevention Program (DPP) Study Results:
Lifestyle intervention reduced diabetes risk by 58% overall and 71% in adults over 60. This was more effective than medication (metformin reduced risk by 31%).
Lifestyle Changes That Work
1. Lose 7% of Body Weight
If you weigh 200 lbs, losing just 14 lbs can cut your diabetes risk in half. Even 5% weight loss provides significant benefits.
How to Achieve It:
- Set a realistic goal (1-2 lbs per week)
- Track calories and portion sizes
- Focus on sustainable changes, not crash diets
- Combine diet and exercise for best results
Understanding Visceral Fat and Metabolic Syndrome:
Visceral fat (deep belly fat around organs) is strongly linked to insulin resistance and diabetes risk. Unlike subcutaneous fat (under the skin), visceral fat is highly inflammatory and interferes with insulin signaling.
DEXA scans can measure visceral fat precisely, revealing hidden metabolic risk even in people with "normal" BMI. This is especially important for:
- South Asians: Develop diabetes at lower BMI (often BMI 23-27) due to higher visceral fat at the same weight
- "Metabolically obese normal weight": Normal BMI but high body fat percentage and excess visceral fat
- People with prediabetes: Visceral fat > 100 cm² on DEXA strongly predicts progression to diabetes
Why this matters: A South Asian person with BMI 24 (considered "normal" by standard criteria) may have 30% more visceral fat than a person of European ancestry at the same BMI - explaining higher diabetes rates despite lower BMI thresholds.
Good news: Exercise and weight loss preferentially reduce visceral fat, improving insulin sensitivity even before significant weight loss occurs.
2. Get 150 Minutes of Exercise Per Week
Moderate-intensity activity (brisk walking, swimming, cycling) for 30 minutes, 5 days per week. Exercise makes your cells more sensitive to insulin.
Getting Started:
- Start with 10-minute walks, 3 times a day
- Add resistance training 2-3 times per week
- Find activities you enjoy (dancing, gardening, sports)
- Track steps with a pedometer (aim for 10,000 steps/day)
3. Eat a Diabetes-Prevention Diet
Focus on foods that don't spike blood sugar and promote weight loss.
✓ Eat More:
- Non-starchy vegetables (leafy greens, broccoli, peppers)
- Whole grains (brown rice, quinoa, oats)
- Lean protein (chicken, fish, beans, tofu)
- Healthy fats (nuts, avocado, olive oil)
- High-fiber foods (keeps blood sugar stable)
✗ Eat Less:
- Sugary drinks (soda, juice, sweet tea)
- Refined carbs (white bread, white rice, pastries)
- Processed foods and fast food
- Red and processed meats
- High-sugar snacks and desserts
4. Get 7-9 Hours of Quality Sleep
Poor sleep worsens insulin resistance and increases appetite hormones. Sleep is as important as diet and exercise.
Sleep Hygiene Tips:
- Keep a consistent sleep schedule (same bedtime/wake time)
- Avoid screens 1 hour before bed
- Keep bedroom cool, dark, and quiet
- Limit caffeine after 2pm
5. Manage Stress
Chronic stress raises cortisol, which increases blood sugar and promotes belly fat storage.
Stress Reduction Strategies:
- Practice mindfulness or meditation (10 min/day)
- Deep breathing exercises
- Regular physical activity (dual benefit!)
- Social support and connection
Medications for Prediabetes and Diabetes
Medications may be recommended in addition to lifestyle changes, especially if you're at very high risk or have difficulty losing weight.
Metformin (for Prediabetes)
First-line medication for diabetes prevention. Consider if you have prediabetes (HbA1c 5.7-6.4%) plus:
- BMI ≥ 35
- Age < 60 years
- Women with history of gestational diabetes
Reduces diabetes risk by 31% over 3 years. Safe, inexpensive, well-tolerated.
GLP-1 Receptor Agonists (for Diabetes & Weight Loss)
Powerful medications for blood sugar control and weight loss. Also protect heart and kidneys.
Examples: Semaglutide (Ozempic, Wegovy), liraglutide (Victoza), dulaglutide (Trulicity)
Recommended for type 2 diabetes, especially if overweight or with cardiovascular disease.
SGLT2 Inhibitors (for Diabetes with Heart/Kidney Benefits)
Lower blood sugar by helping kidneys remove excess glucose through urine. Strong evidence for heart failure and kidney protection.
Examples: Empagliflozin (Jardiance), dapagliflozin (Farxiga), canagliflozin (Invokana)
Recommended for type 2 diabetes with heart disease, heart failure, or chronic kidney disease.
Other Diabetes Medications
Your doctor may prescribe other medications based on your specific situation:
- Insulin: For advanced diabetes when pancreas can't make enough
- Sulfonylureas: Stimulate insulin production (glipizide, glyburide)
- DPP-4 Inhibitors: Help body produce more insulin (sitagliptin, linagliptin)
Monitoring and Follow-Up
If you have prediabetes:
Check HbA1c at least once per year to monitor for progression to diabetes
If you have diabetes:
Check HbA1c every 3-6 months (goal: < 7% for most adults)
Monitor for complications:
Annual eye exam, kidney function tests (eGFR/UACR), foot exam, blood pressure, cholesterol
Consider continuous glucose monitoring (CGM):
Especially helpful if on insulin or struggling with blood sugar control
If you've been diagnosed with type 2 diabetes, remember: it's manageable. Many people live long, healthy lives with diabetes by following their treatment plan.
Your Diabetes Management Goals:
HbA1c: < 7% (individualized based on age, complications, life expectancy)
Blood Pressure: < 130/80 mmHg
LDL Cholesterol: < 70 mg/dL (if high cardiovascular risk)
Weight Loss: 5-15% of body weight can improve blood sugar significantly
Preventing Complications
The key to living well with diabetes is preventing long-term complications:
- Heart Disease & Stroke: Take aspirin and statin as prescribed, control BP
- Kidney Disease: Annual UACR screening, ACE inhibitor/ARB or SGLT2 inhibitor
- Eye Problems: Annual dilated eye exam to catch retinopathy early
- Nerve Damage: Check feet daily, annual foot exam with doctor
- Dental Issues: Dental cleaning twice per year
Use this checklist to guide your conversation about diabetes prevention and management:
Key Takeaways
Prediabetes is reversible with lifestyle changes (58% risk reduction)
Weight loss of just 7% can cut diabetes risk in half
150 minutes of exercise per week is as powerful as medication
South Asians and high-risk populations may need intervention at HbA1c 5.4-5.6%
Medications like metformin, GLP-1 RAs, and SGLT2 inhibitors can help prevent or manage diabetes
Regular monitoring (HbA1c, kidney function, eye exams) prevents complications
Type 2 diabetes is manageable - many people live long, healthy lives with proper treatment
Reference:
Based on the American Diabetes Association Standards of Care in Diabetes—2026. This guide translates the latest clinical guidelines into patient-friendly language to help you understand diabetes prevention, diagnosis, and management.
American Diabetes Association Professional Practice Committee. Standards of Care in Diabetes—2026. Diabetes Care. 2026;49(Suppl 1):S1-S340. doi:10.2337/dc26-SINT