Your plan after the blood test
Last week I explained why I now screen with the LP-IR score and fasting C-peptide. This week I’ll show you how to act on your results.
Your two numbers put you in one of four groups. Within each group, your plan depends on how much belly fat you have. To measure it, wrap a tape measure around your waist at your belly button and divide that number by your height. Under 0.5 means little to no belly fat, and 0.6 or more means a lot. Anything in between is a bit to medium.
Find your group and your belly fat level, and you have your starting plan. We’ll fit it to you on your 90-minute strategy call.
Before you change anything: If you take diabetes medication, especially insulin, a sulfonylurea such as glipizide, or an SGLT2 inhibitor such as Jardiance or Farxiga, talk to your doctor before you start keto or fasting. Your doses may need to change, and an SGLT2 inhibitor combined with keto can cause ketoacidosis, a medical emergency. Talk to your doctor about blood pressure medication too, because cutting carbs can drop your blood pressure quickly.
While some people do adopt a ketogenic diet on their own, I don’t recommend it. I recommend working with someone who can help you get it right. As you’ll see, most of the time I don’t even recommend a strict keto diet, though I think it’s a very healthy diet and many people manage it very well.
These diet recommendations are for insulin resistance issues only! They are not for cardiovascular, muscle building, or bone building. And remember, this is my research, it is for informational purposes, not medical advice.
The metabolic action matrix
Fasting C-peptide: Optimal is 0.5 to 1.5 ng/mL. Above 1.5 means your pancreas is under strain. Read it alongside your fasting glucose, A1c, and creatinine. If your C-peptide is 1.5 or below but your fasting glucose is 100 mg/dL or higher, or your A1c is 5.7% or higher, your pancreas may not be keeping up. See your doctor before you follow any plan below.
LP-IR score: Optimal is under 30. A score of 30 to 45 means early insulin resistance, 46 to 67 means insulin resistant, and Labcorp flags 68 or higher.
The matrix splits at a C-peptide of 1.5 and an LP-IR of 45.
Quadrant 1: optimal profile
(C-peptide 1.5 ng/mL or below and LP-IR 45 or below)
Status: High cellular insulin sensitivity and low pancreatic strain. If your LP-IR is 30 to 45, you have early insulin resistance, so follow the plan for a bit of belly fat even if you’re lean.
Little to no belly fat
Primary action: Maintenance and performance.
Nutrition: Eat a flexible whole-food diet with diverse complex carbohydrates, high fiber, and adequate protein. You don’t need to restrict carbs.
A bit of belly fat (subcutaneous, stubborn fat)
Primary action: Body recomposition. Build muscle while you eat slightly less than you burn.
Nutrition: Keep carbs in your diet, but cut 200 to 300 calories a day and eat high protein, 0.8 to 1.0 grams per pound of body weight.
Medium to high belly fat (metabolic mismatch)
Primary action: Investigate non-insulin drivers.
Context: If your labs are pristine but you have significant belly fat, something other than high insulin is most likely driving it: eating more than you burn, chronic stress and high cortisol, poor sleep, or alcohol.
Action plan: Prioritize 7 to 8 hours of sleep, stress management, less alcohol, and more daily activity.
Quadrant 2: compensated resistance
(C-peptide above 1.5 ng/mL and LP-IR 45 or below)
Status: Your pancreas is making extra insulin to keep your tissues looking normal. Check your creatinine first, because reduced kidney function also raises C-peptide.
Little to no belly fat
Primary action: Meal frequency reset.
Context: You have early, hidden high insulin, often from frequent snacking or high-glycemic foods.
Nutrition: Eliminate all snacking. Move to 3 meals a day. You don’t need to go strict low-carb. Choose low-glycemic, high-fiber carbs.
Lifestyle: Take a 10-minute walk after each meal. Working muscles pull glucose out of your blood without needing extra insulin.
A bit of belly fat (early visceral fat)
Primary action: Time-restricted eating (16:8).
Nutrition: Eat within an 8-hour window, such as 10 AM to 6 PM. Sixteen hours a day without food lets your baseline insulin drop, which makes stored belly fat easier to burn.
Medium to high belly fat
Primary action: Moderate low-carb plus longer fasting windows.
Nutrition: Cut total carbohydrates to 75 to 100 grams a day, and get them from whole foods instead of refined carbs. Combine that with 16:8 or 18:6 time-restricted eating to drive down your baseline insulin.
Goal: Follow this for 6 to 12 months to reduce liver and pancreatic fat and bring your C-peptide below 1.5 ng/mL.
Quadrant 3: uncompensated cell stress
(C-peptide 1.5 ng/mL or below and LP-IR above 45)
Status: Your lipoproteins show insulin resistance, but your pancreas isn’t making extra insulin.
Check this first, at any belly fat level: Make sure your fasting glucose is under 100 mg/dL and your A1c is under 5.7%. If either is high, your pancreas may be tiring out, and you need to see your doctor before you follow the plans below. If both are normal, look for causes of high triglycerides that have little to do with insulin, such as alcohol, genetics, an underactive thyroid, or medications like beta-blockers, steroids, and oral estrogen. Ask your doctor for a thyroid test (TSH).
Little to no belly fat
Primary action: Mitochondrial repair and fat-quality swap.
Context: Poor fat burning in your muscles or a sensitivity to saturated fat may drive this pattern. Your insulin isn’t high, so keto’s main benefit doesn’t apply, and a high-saturated-fat diet raises LDL particles in many people.
Nutrition: Do NOT go high-saturated-fat keto. Adopt a Mediterranean-style diet. Swap butter and bacon for extra virgin olive oil, avocados, nuts, and wild-caught fish.
A bit to medium belly fat
Primary action: Zone 2 cardio plus muscle building.
Nutrition: Eat a moderate-carb diet high in monounsaturated fat. Eliminate refined seed oils and ultra-processed foods.
High belly fat
Primary action: Steady weight loss, once the glucose check above comes back normal.
Action plan: Lose weight steadily on a high-fiber diet rich in monounsaturated fat.
Quadrant 4: overt insulin resistance
(C-peptide above 1.5 ng/mL and LP-IR above 45)
Status: Heavy pancreatic strain and significant insulin resistance in your tissues. Check your creatinine first, because reduced kidney function also raises C-peptide.
Every plan in this group uses keto. Keto raises LDL and ApoB in some people, so we retest your ApoB after 3 months. If it rises sharply, you stay low-carb and we swap saturated fat for olive oil, nuts, and fish.
Little to a bit of belly fat (acute, lifestyle driven)
Primary action: An 8-to-12-week "circuit breaker" keto reset.
Nutrition: Follow a strict ketogenic diet, under 30 grams of net carbs a day, for 2 to 3 months.
Goal: Give your overworked pancreas immediate relief, clear liver fat, and re-sensitize your tissues before you move to a whole-food Mediterranean diet.
Medium belly fat (20 to 40 lbs to lose)
Primary action: A 6-to-12-month therapeutic keto and fasting protocol.
Nutrition: Combine a ketogenic diet with 16:8 time-restricted eating.
Timeline: Retest your bloodwork at 6 months to track the drop in both C-peptide and LP-IR.
A lot of belly fat (more than 40 lbs to lose)
Primary action: A ketogenic lifestyle for 1 to 3 years or more.
Context: Reversing decades of fat in your belly, liver, and muscles takes time. An 8-week reset isn’t enough.
Nutrition: Follow a ketogenic diet long-term. Keeping your baseline insulin low makes it easier to burn stored body fat.
Why it works long-term: Keto suppresses appetite, which makes a long calorie deficit easier to keep, and it steadily clears liver and visceral fat over 12 to 36 months.
If this sounds complicated, it’s because it is. But I can break it down for you and we can come up with a plan together. Once you have your results, reply to book your 90-minute strategy call, and we’ll fit this plan to you.