Kraft Patterns
The Hidden Story of Your Insulin Response
Dr. Joseph Kraft tested over 14,000 patients with extended glucose tolerance tests including insulin measurements. His work revealed that insulin dysfunction begins years—sometimes decades—before blood glucose becomes abnormal.
Who Should Know About Kraft Patterns?
- •Those with family history of Type 2 diabetes
- •People with "normal" glucose but metabolic symptoms
- •Anyone interested in true early detection
- •Those whose standard tests seem fine but feel something is off
By the time fasting glucose rises, you may have had insulin resistance for 10-20 years. HOMA-IR gives you a snapshot. Kraft patterns show the full movie.
What is a Kraft Test?
A 5-hour Oral Glucose Tolerance Test (OGTT) with insulin measurements at each time point. Standard OGTT only measures glucose—Kraft adds insulin to reveal the full picture.
The 5 Kraft Patterns
Pattern I
Healthy insulin response
Characteristics:
- •Insulin peaks at 30-60 minutes
- •Returns to baseline by 2-3 hours
- •Fasting insulin typically < 10 μU/mL
- •Peak insulin < 60 μU/mL
Excellent insulin sensitivity. Your pancreas produces the right amount of insulin at the right time.
Pattern II
Delayed insulin peak
Characteristics:
- •Insulin peaks at 1-2 hours instead of 30-60 min
- •Delayed return to baseline
- •Fasting glucose still normal
- •Fasting insulin may be normal
Early insulin resistance. Cells are becoming less responsive, so more insulin is needed for longer.
Pattern III
Delayed and elevated peak
Characteristics:
- •Peak insulin at 2+ hours
- •Peak often > 100 μU/mL
- •Still elevated at 3-4 hours
- •2-hour glucose often in prediabetic range
Significant insulin resistance. Pancreas is working overtime to maintain glucose control.
Pattern IV
Fasting hyperinsulinemia
Characteristics:
- •Elevated fasting insulin (> 15-20 μU/mL)
- •Stays elevated throughout test
- •Fasting glucose may still be normal
- •HOMA-IR typically elevated
"Diabetes in situ" — metabolically diabetic but glucose hasn't risen yet. Critical intervention window.
Pattern V
Flat or minimal response
Characteristics:
- •Little to no insulin response to glucose
- •Flat curve throughout
- •Glucose rises and stays high
- •Low or absent C-peptide
Beta cell exhaustion or Type 1 diabetes. Pancreas can no longer produce adequate insulin.
"Those with cardiovascular disease not identified with diabetes... are simply undiagnosed."
The Hidden Timeline of Diabetes
Why This Matters
Earlier Detection
Standard tests miss years of developing insulin resistance. By the time glucose rises, you're far into the disease process.
Targeted Intervention
Pattern II and III are often fully reversible with lifestyle changes. Pattern IV requires aggressive intervention.
Beyond HOMA-IR
HOMA-IR is a 2-hour snapshot. Kraft patterns show dynamic response—how your body handles the challenge of glucose.
Predicting the Future
Your pattern today predicts your metabolic trajectory. Catching problems early allows prevention, not just treatment.
How to Get This Test
Request 5-hour OGTT with insulin
Ask for glucose AND insulin at fasting, 30 min, 1h, 2h, 3h, and 4-5h
Prepare properly
Fast 10-12 hours. Eat normally for 3 days prior (no low-carb). Stay seated during test.
Get the right labs
Many labs only offer standard OGTT. LabCorp and Quest can do extended with insulin.
Interpret with context
Patterns matter more than individual values. Consider your other metabolic markers.
Note: This test may not be covered by insurance for screening purposes. Discuss medical necessity with your provider.
If Full Kraft Test Isn't Available
While less complete, these approximations can help:
2-hour OGTT with Insulin
Abbreviated version. Can detect delayed peak (Pattern II/III).
C-Peptide
Measures insulin production. Useful for Pattern V assessment.
Key Takeaways
- 1Insulin dysfunction precedes glucose problems by 10-20 years
- 2Pattern I is optimal; Patterns II-IV represent progressive dysfunction
- 3Pattern IV ("diabetes in situ") is metabolically diabetic despite normal glucose
- 4HOMA-IR can approximate Kraft testing using just fasting values
- 5Lifestyle intervention is most effective in early patterns (II/III)
References
- [1]Kraft JR. Detection of Diabetes Mellitus In Situ (Occult Diabetes). Laboratory Medicine. 1975. 6(2):10-22 [Link]
- [2]Kraft JR. Diabetes Epidemic & You. Book. 2008. [Link]
- [3]Crofts C, et al. Identifying hyperinsulinaemia in the absence of impaired glucose tolerance: An examination of the Kraft database. Diabetes Res Clin Pract. 2016. PMID: 27344544
- [4]Hayashi T, et al. Patterns of insulin concentration during the OGTT predict the risk of type 2 diabetes in Japanese Americans. Diabetes Care. 2013. PMID: 23275353
Medical Disclaimer
The Kraft Patterns guide provided on Metabolicum is for educational and informational purposes only. It is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.