Metabolic

Peptides, MK-677 and your blood sugar

Why growth hormone and its secretagogues push fasting glucose and HbA1c up, how to read the numbers, and what people do about it.

Updated 2026-09-27 · Part of the Magno guides

Growth hormone raises blood sugar. That is not a side effect, it is part of what the hormone does. Anything that raises growth hormone, whether it is GH itself, MK-677, ipamorelin or CJC-1295, raises fasting glucose and blunts insulin. The peptide crowd finds this out on their first panel after starting.

The three numbers to read together

• Fasting glucose moves first. Under 100 mg/dL (5.6 mmol/L) is normal; 100 to 125 is prediabetes on paper.
• Fasting insulin shows how hard the pancreas is working to keep glucose there. Under 8 µIU/mL is where people aim. Glucose normal with insulin high is early resistance, and the best time to act.
• HbA1c averages three months of sugar. Under 5.7 percent is normal. On testosterone it can read a little low, because red cells turn over faster and donations replace old cells with new, so do not let a good HbA1c override a bad fasting glucose.

Why it happens

Growth hormone tells the liver to release glucose and tells muscle and fat to use less of it. MK-677 does this around the clock, which is why it is the most common cause of a surprise prediabetic reading in someone lean and training hard. Trenbolone and some orals worsen insulin sensitivity too. Poor sleep and high cortisol add to it.

What people usually do

1. Move the dose. MK-677 or GH before bed, on an empty stomach, no carbohydrate for a couple of hours. Or lower the dose.
2. Walk after meals. Ten to fifteen minutes after the two biggest meals does more for post-meal glucose than most supplements.
3. Fiber and fewer refined carbohydrates. Twenty-five grams of fiber a day is the usual target.
4. Berberine at 500 mg two or three times a day with meals is the supplement people reach for; it behaves a little like metformin. A doctor can prescribe metformin itself, and some do for people on GH.
5. Retest in three months. HbA1c needs that long to reflect a change.

When to stop and get help

Fasting glucose over 126 mg/dL (7 mmol/L) on two tests is diabetes, whatever caused it. That is a doctor visit, not a dose tweak.