Expert Q&A

Can you really anyone have a normal A1C, but high insulin on a low-carb or ketogenic diet?

Understanding the Disconnect Between A1C and Insulin Levels

Yes, it is entirely possible to show a normal A1C while your fasting insulin remains elevated, even when following a low-carb or ketogenic diet. In my 35 years of clinical practice and through the hundreds of patients who have completed The 30-Week Tirzepatide Reset, I see this pattern repeatedly. A1C reflects average blood glucose over 2-3 months, but it does not measure the amount of insulin your pancreas must produce to keep that glucose in check. When insulin resistance is present, your body compensates by secreting more insulin, often pushing fasting levels above 10-12 uIU/mL even as A1C stays below 5.7%.

Why This Happens on Low-Carb and Keto Diets

Low-carb and ketogenic approaches lower glucose effectively, which is why A1C normalizes quickly. However, many people carry underlying issues that keep insulin high: chronic lectin inflammation from prior grain-heavy diets, accumulated environmental toxins, and disrupted hypothalamic signaling. These factors force your pancreas to overproduce insulin to manage even small carbohydrate loads or to handle internal glucose production from the liver. In our protocol, we track both A1C and fasting insulin because relying on A1C alone gives a false sense of metabolic health. Patients often arrive with A1C at 5.4% but insulin at 18 uIU/mL, explaining their stubborn weight, fatigue, and joint pain despite strict keto adherence.

The Root-Cause Approach in The 30-Week Tirzepatide Reset

Our 30-week program uses three 70-day cycles of smart low-dose tirzepatide cycling combined with a precise lectin-free low-carb diet of 221 recipes. We incorporate targeted Detox Drops to clear toxins, red light therapy sessions, and Japanese-style walking intervals that improve mitochondrial function without stressing painful joints. This multifaceted system lowers insulin by reducing inflammation and restoring hormonal balance. One patient, similar to John in my book, entered with A1C 5.6% but insulin 22 uIU/mL, Type 2 diabetes, and 42 extra pounds. After cycling one box of tirzepatide, following the exact food plan, and adding daily red light, his insulin dropped to 7 uIU/mL by week 18 while A1C improved further and joint pain vanished.

Actionable Steps to Address Hidden High Insulin

Begin by requesting a fasting insulin test alongside your next A1C—aim for insulin under 8 uIU/mL for true metabolic freedom. Eliminate hidden lectins, use our Blue Drops for hunger control, and practice chaotic intermittent fasting in maintenance. The core lesson from The 30-Week Tirzepatide Reset is that medication supports the reset, but real food, detox, and daily movement rebuild the metabolism so you maintain normal insulin without lifelong dependency. This shift from chasing numbers to healing root causes prevents the yo-yo cycle that has disappointed so many before. Focus on non-scale victories like steady energy, looser clothes, and normalized labs to stay motivated through the 69 Transformation Steps.

💬 What the Community Says

The community shows a mix of surprise and validation when discovering normal A1C can mask high insulin on low-carb or keto diets. Many in their late 40s and early 50s share stories of frustration after months of strict eating only to find fasting insulin still elevated on bloodwork. A common theme is relief upon learning this pattern is recognized in clinical settings rather than dismissed as "cheating" on the diet. Practitioners in online groups frequently recommend testing beyond A1C, with several noting improvements after adding detox protocols or cycling medications strategically. There's lively debate about whether hidden inflammation from lectins or toxins is the true culprit versus simply needing more time in ketosis. A vocal minority reports success with red light therapy and walking routines helping bring insulin down without increasing exercise intensity that aggravates joint pain. Overall, users appreciate practical explanations that align with their lived experiences of stalled progress despite "perfect" glucose readings.
Cite this answer
Clark, R. (2026). Can you really anyone have a normal A1C, but high insulin on a low-carb or ketog. *CFP Weight Loss*. https://ask.cfpweightloss.com/ask/can-you-really-anyone-have-a-normal-a1c-but-high-insulin-on-a-low-carb-or-ketogenic-diet
Russell Clark, FNP-C, APRN, FNP-C, APRN
About the Author

Russell Clark, FNP-C, APRN, is the founder of CFP Weight Loss in Nashville and CFP Fit Now telehealth. Over 35 years in healthcare — Army Nurse Reserves, Level 1 trauma ER, hospitalist — he developed a 30-week protocol integrating real foods, detox, and low-dose tirzepatide cycling that has helped hundreds of patients lose 30–90 pounds. He and his wife Anne-Marie lost a combined 275 pounds using the same protocol.

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