Does it affect thyroid function?

What this archive is for. Trials of the compound come first, ranked by how many people were actually given it. Studies that only observed people are below them and labelled.

1. 01GHRP-6PeptideLimited. People have taken it in a published study, but fewer than 100 of them. 5 completed trials, 42 people given it.8 reported

   27 people given it2 trials2 found nothing

   • found nothingThe first clean human demonstration that this peptide releases growth hormone, and it does. 18 healthy men got GHRP-6 into a vein at three dose levels. Growth hormone peaked far higher than on the dummy and climbed steeply with dose. At half doses it worked with the natural releasing hormone to do more than either alone. Prolactin and cortisol roughly doubled, but only at the top dose. Two other pituitary hormones did not move. Nothing went wrong clinically. This measures a hormone in blood, not a health outcome.

     The numbers 18 normal men given GHRP-6 at 0.1, 0.3 and 1.0 micrograms per kilogram intravenously. Mean peak serum GH was 1.2 on placebo and 7.6, 16.5 and 68.7 micrograms per litre across doses, and submaximal doses combined with GHRH released GH synergistically. Prolactin and cortisol rose about twofold above basal only at the top dose; LH and TSH were unchanged over the first hour. No adverse clinical effects or laboratory abnormalities.

     Journal of Clinical Endocrinology and Metabolism, 1990· 18 people

   • found nothingThe longest anyone has been kept on this peptide, and the response was already fading by the end. Nine healthy young men had GHRP-6 or salt water dripped in for thirty-four hours. Total growth hormone output roughly doubled and IGF-1 rose modestly. The natural pulse pattern did not change. By the end the pituitary was answering less: a later dose of GHRP-6 produced a smaller rise, and two other pituitary hormones also responded less to their own trigger. That is the tolerance problem, measured directly, in people.

     The numbers Nine healthy young men infused with GHRP-6 or saline for 34 hours, the longest published human exposure. Integrated GH concentration rose to 2,908 against 1,374 micrograms x min per litre and IGF-1 from 252 to 312 micrograms per litre, with no change in GH pulse frequency or interpulse concentration. Partial desensitization was visible by the end: the GH response to a later GHRP-6 bolus and the TSH and prolactin responses to TRH were all smaller, and baseline TSH was lower.

     Journal of Clinical Endocrinology and Metabolism, 1993· 9 people

2. 02BPC-157PeptideLimited. People have taken it in a published study, but fewer than 100 of them. 3 completed trials, 31 people given it.10 reported

   2 people given it1 trial1 found nothing

   • found nothingA study this small cannot show that anything is safe. Two healthy adults were given BPC-157 into a vein, 10 mg on the first day and 20 mg on the second. Neither reported side effects, and blood tests covering the heart, liver, kidneys, thyroid and blood sugar did not shift. That is worth knowing, and it is all it is. Two people cannot reveal a side effect that strikes one person in fifty, let alone one in a thousand.

     The numbers Two adults received 10 mg intravenously on day 1 and 20 mg on day 2. No adverse effects were reported and cardiac, liver, kidney, thyroid and glucose laboratory values did not change meaningfully. Two subjects cannot characterise safety.

     Alternative Therapies in Health and Medicine, 2025· 2 people

3. 03GalaninPeptideLimited. People have taken it in a published study, but fewer than 100 of them. 4 completed trials, 21 people given it.

   0 people given it1 trial1 found nothing

   • found nothingThe first time galanin was given to people, it set off a surge of growth hormone. Ten healthy volunteers were infused for an hour at one of two rates. Growth hormone climbed many times over, further at the higher rate. The hormone behind milk production rose a little. Stress and thyroid hormones did not move, and neither did heart rate or blood pressure. The only complaints were a passing bitter taste and extra saliva. Sugar cleared from the blood more slowly, with insulin unchanged.

     The numbers The first human study. Galanin infused for 60 minutes into healthy volunteers at 7.8 pmol/kg per minute (n=4) or 33.2 pmol/kg per minute (n=6). Plasma growth hormone rose from 2.8 to a mean peak of 48.5 mU/L at the high dose and from 2.5 to 23.5 mU/L at the low dose; prolactin rose from 176 to 274 mU/L. No change in cortisol, TSH, FSH or LH. No change in heart rate or blood pressure at these doses; the only symptoms were a transitory bitter taste and slight hypersalivation. Galanin reduced glucose clearance after an intravenous glucose bolus without significantly affecting plasma insulin.

     The Lancet, 1986· number of people not given

Vitamins, minerals, amino acids and botanicals sold over the counter, held to the same standard.

1. 01ForskolinSupplementLimited. People have taken it in a published study, but fewer than 100 of them. 2 completed trials, 53 people given it.5 reported

   23 people given it1 trial1 found nothing

   • found nothingThe same supplement was tested in women and it did not work. 23 mildly overweight women took a 10 percent Coleus forskohlii extract twice a day or a dummy for 12 weeks, seven on the extract. Fat mass, lean mass and body fat percentage came out the same in both groups. Slight leanings toward less weight gain were too weak to call. Blood fats, liver enzymes, thyroid, insulin, heart rate and blood pressure were unchanged. Seven people is too few to spot anything but a huge effect.

     The numbers 23 women randomised double-blind to 250 mg of a 10 percent Coleus forskohlii extract twice daily (n equals 7) or placebo (n equals 12) for 12 weeks. No significant differences in fat mass, fat-free mass or body fat percentage. Non-significant trends toward mitigating gains in body mass (p equals 0.10) and scanned mass (p equals 0.08). Treated participants reported less hunger and fullness. No clinically significant changes in blood lipids, liver or muscle enzymes, thyroid hormones, insulin, heart rate or blood pressure. The authors concluded it does not appear to promote weight loss but may help mitigate weight gain.

     Journal of the International Society of Sports Nutrition, 2005· 23 people

2. 02AshwagandhaSupplementLimited. People have taken it in a published study, but fewer than 100 of them. 1 completed trial, none stating how many people.2 reported

   0 people given it1 trial

   • Adults who took a strong root extract felt less stressed than those on a dummy pill. This measured how people felt, not how long they lived or their thyroid health.

     The numbers Randomised full-spectrum root extract versus placebo. Reported improvements on stress scales. Symptom trial, not a longevity or thyroid-outcome trial.

     Indian Journal of Psychological Medicine, 2012· number of people not given

Approved drugs, biologics and hormones that have been measured for this. They are here because leaving them out would misrepresent the evidence, and they are below the peptides because that is not what most people come here to read.

1. 01AlbiglutideBiologicStrong. At least two finished studies in people, and at least 1,000 people who took it. 2 completed trials, 10,304 people given it.

   9,463 people given it1 trial

   • Albiglutide cut heart attacks, strokes and cardiac deaths in people with diabetes and heart disease. Nearly ten thousand adults across 28 countries were split by chance between the drug and a dummy injection, and followed for about a year and a half. Nobody involved knew which. Seven in a hundred on the drug had a heart attack, stroke or cardiac death, against nine in a hundred on the dummy. Pancreas and thyroid problems were rare and evenly spread. GlaxoSmithKline funded it.

     The numbers 9,463 adults aged 40 and over with type 2 diabetes and cardiovascular disease, 610 sites, 28 countries, randomised 1:1 to albiglutide 30 to 50 mg weekly or placebo, median follow-up 1.6 years. Primary composite (cardiovascular death, myocardial infarction, stroke): 338 of 4,731 (7 percent) against 428 of 4,732 (9 percent), hazard ratio 0.78 (95 percent CI 0.68 to 0.90), superiority P equals 0.0006. Pancreatitis 10 against 7, pancreatic cancer 6 against 5, medullary thyroid carcinoma 0 against 0. Funded by GlaxoSmithKline.

     Lancet, 2018· 9,463 people

2. 02LeptinBiologicModerate. At least one finished study in people, and at least 100 people who took it. 6 completed trials, 844 people given it.5 reported

   3 people given it1 trial

   • Give leptin to the rare children who have none and it transforms them. Three children born unable to make leptin were injected daily for up to four years. Appetite fell, fat mass fell, insulin and blood fats came back towards normal, and puberty arrived at the right age. Immune cells that had been depleted recovered too. This is replacing a missing hormone in people who lack it. It says nothing about giving leptin to people who have plenty. Public money paid for the work.

     The numbers Three children with congenital leptin deficiency treated with daily subcutaneous recombinant human leptin for up to 4 years: sustained reductions in appetite, fat mass, hyperinsulinaemia and hyperlipidaemia, rapid rise in thyroid hormones, appropriately timed puberty, and reversal of reduced CD4 T cell numbers and impaired T cell function. Non-US government funded.

     Journal of Clinical Investigation, 2002· 3 people