🌙 Running GH Peptides or MK-677

What this panel can settle, and by what logic

Nine markers, and the only reading that makes sense is as a trade: what the compound is buying, and what it is being paid for with.

1. IGF-1 (Insulin-like Growth Factor 1) is the efficacy marker because Growth Hormone, Serum cannot be one. Growth hormone is secreted in pulses and a random serum value is close to uninterpretable, which is why diagnosing deficiency requires provocative testing rather than a basal measurement Yuen 2023. IGF-1 integrates that pulsatility into one number. A long-acting growth hormone-releasing hormone analog produced sustained elevation of both growth hormone and IGF-1 in healthy adults Teichman 2006, so a rise here is the expected pharmacology working.
2. Fasting Insulin is the price, and this is what the trial actually measured. In a 2-year randomized placebo-controlled trial of the oral ghrelin mimetic MK-677 in adults aged 60 to 81, growth hormone and IGF-1 rose into the young-adult range and fat-free mass increased by 1.1 kg against a 0.5 kg loss on placebo — and in the same participants fasting blood glucose rose by an average of 0.3 mmol/L, about 5 mg/dL, with insulin sensitivity decreasing Nass 2008. Measuring IGF-1 without measuring fasting insulin buys you the first half of that sentence.
3. HbA1c (Hemoglobin A1c) confirms whether the insulin change reached the glucose. It integrates 2 to 3 months Chen 2022, so it is the marker that says whether a rising insulin is being compensated for or is failing to be.
4. TSH (Thyroid-Stimulating Hormone) with Free T4 (Thyroxine) catches the effect nobody expects. Growth hormone increases peripheral conversion of thyroxine and can unmask a marginal thyroid, and free T4 falls before TSH reacts, which is why both are on the list rather than TSH alone.

What it cannot settle, and what would

It cannot tell you whether the extra tissue is useful. The same trial that showed a real gain in fat-free mass also reported that the increase did not produce changes in strength or function Nass 2008. That is the most important sentence on this page: the marker moved, the body composition moved, and the outcome people buy it for did not. Nothing on this panel measures strength, and a scale weight on a working set costs nothing.

A single Growth Hormone, Serum value proves nothing at all. Secretion is pulsatile and stimulated by sleep, fasting and exercise, and stimulation testing exists because basal levels cannot be interpreted Yuen 2023. It is on this panel as context for the IGF-1 and should never be read alone.

It cannot tell you what the vial contained. A rise in IGF-1 shows that something raised IGF-1. It does not confirm which peptide, at what purity, or at what dose — and it cannot distinguish a secretagogue from directly administered growth hormone Teichman 2006.

And it cannot answer the cancer question. The concern about pushing IGF-1 above an age-matched range is epidemiological and long-term. There is no marker on this list that detects the outcome, and a normal panel is not evidence about it Yuen 2023.

Draw conditions that decide whether the money is wasted

One marker here is timing-proof and one is destroyed by ordinary behavior, and most people get them the wrong way round.

1. IGF-1 (Insulin-like Growth Factor 1) tolerates timing; keep it consistent anyway. It is an integrated signal rather than a pulse, so morning or afternoon changes it little Yuen 2023. The reason to fix the conditions is that you are comparing it with itself in 8 weeks.
2. Do not draw Growth Hormone, Serum after training. A single bout of high-intensity interval exercise raised growth hormone secretion measured across the following 12.5 hours Deemer 2018, so a value taken the morning after a hard session says nothing about your protocol.
3. Fast 9 to 12 hours for the glucose on the Comprehensive Metabolic Panel (CMP) and the Fasting Insulin. These are the safety half of the panel and they are the half that a non-fasting draw deletes Krhač 2019. Given the effect being looked for is roughly 5 mg/dL of fasting glucose Nass 2008, a fed sample is not a slightly noisy measurement, it is no measurement.
4. Baseline before the first dose, and no biotin for 3 days. IGF-1, TSH (Thyroid-Stimulating Hormone) and Free T4 (Thyroxine) are commonly streptavidin-based, and MK-677 in particular raises appetite, so this is an audience taking supplements.

How you would know it answered your question, and what each pattern means next

Recheck at 8 to 12 weeks. That interval is set by IGF-1, which reaches a new steady state within weeks of a dose change, and by HbA1c (Hemoglobin A1c), which needs 3 months to report one Chen 2022.

• IGF-1 (Insulin-like Growth Factor 1) risen, Fasting Insulin and HbA1c (Hemoglobin A1c) unchanged: the trade is being made on acceptable terms. Recheck at 12 weeks and hold the dose.
• IGF-1 risen with fasting insulin rising and fasting glucose up by a few mg/dL: the expected metabolic cost, measured Nass 2008. Reduce the dose or stop, and repeat the glucose and insulin at 8 weeks — those two recover faster than HbA1c will show Krhač 2019.
• IGF-1 above the top of the age-matched range: the range is age-specific for a reason and more is not better here Yuen 2023. Reduce, and re-measure at 8 weeks.
• IGF-1 flat after 8 weeks at a full dose: either the compound is not doing what it claims or it is not what it claims. Neither is fixed by a longer run, and a random Growth Hormone, Serum value will not settle it Yuen 2023.
• Free T4 falling with a normal TSH (Thyroid-Stimulating Hormone): a real and underrecognized effect of this class. It goes to a clinician rather than into a dose adjustment.

Sources read for these sections

• Nass R, et al. Effects of an oral ghrelin mimetic on body composition and clinical outcomes in healthy older adults: a randomized trial. Annals of Internal Medicine 2008 · PMID 18981485
• Yuen KCJ, et al. Diagnosis and testing for growth hormone deficiency (GHD) across the ages: a global view of the accuracy, caveats and cut-offs for diagnosis. Endocrine Connections 2023 · PMID 37052176
• Teichman SL, et al. Prolonged stimulation of growth hormone (GH) and insulin-like growth factor I secretion by CJC-1295, a long-acting analog of GH-releasing hormone, in healthy adults. Journal of Clinical Endocrinology and Metabolism 2006 · PMID 16352683
• Deemer SE, et al. Pilot study: an acute bout of high intensity interval exercise increases 12.5 h GH secretion. Physiological Reports 2018 · PMID 29380957
• Chen Z, et al. Interpretation of HbA1c lies at the intersection of analytical methodology, clinical biochemistry and hematology (Review). Experimental and Therapeutic Medicine 2022 · PMID 36382101
• Krhač M, Lovrenčić MV. Update on biomarkers of glycemic control. World Journal of Diabetes 2019 · PMID 30697366