Growth hormone peptide fragment 176-191, or HGH Frag 176-191, is made from amino acids 177–191 of human growth hormone with an additional tyrosine amino acid. Although growth hormone is well known for accelerating growth, a role for the protein in breakdown fat was first documented in 1959 . Both human growth hormone and hgh fragment 176-191 synthesised from the full protein are capable of inducing weight loss and increasing fat breakdown following long-term treatment in mice . Although it is not completely understood how this happens, it is likely to occur when the peptide binds to beta(3)-adrenergic receptors, which are the major receptors linked to fat breakdown in cells. Hgh fragment 176-191 has more specific effects when compared to the full protein since it stimulates hormone-sensitive lipase and inhibits acetylcoenzyme A carboxylase to reduce the size of fat cells; but it exerts no growth promoting activities . Hgh fragment 176-191 is therefore perfect for breaking down fat without the risk of hyperglycaemia as the peptide results in a short-lived rise in blood glucose and a sustained rise in plasma insulin . In mice, hgh fragment 176-191 led to increased body weight in lean animals, compared with saline-treated animals. This change was in the absence of an increase in fat mass, which means that increases in lean body mass occur with this peptide fragment . Hgh fragment 176-191 peptide was also shown to reduce body weight and adiposity in obese mice . The effects of the peptide were found to occur without significant changes to calorie intake and it has been reported that the peptide either reduces or does not change food intake. All human clinical trials have shown that the peptide is extremely safe. Furthermore, the peptide was shown to have no effect on serum IGF-1 levels, which confirms the hypothesis that hgh frag 176-191 does not act via IGF-1. Results of glucose tolerance tests also demonstrated that the peptide has no negative effect on carbohydrate metabolism. Additionally, no immune response was detected against the peptide in any patients taking the hgh fragment and no studies have reported withdrawal symptoms or serious adverse events . All studies therefore show that the fragment is a safe and effective peptide for fat loss.
Hgh fragment 176-191 has been administered orally and intravenously during clinical trials up to dosages of 400 mcg/kg. Following resuspension of hgh fragment 176-191 5mg in BAC water, dosages of 250 mcg should be injected subcutaneously, three times per day, in the morning, afternoon and evening. It is optimal to inject the peptide on an empty stomach. The reconstituted peptide solution may remain cloudy and this is perfectly normal.
Hgh fragment 176-191 is considered extremely safe and there have been no major reported side effects linked to the peptide in a number of human clinical trials. Mild gastrointestinal discomfort may occur as a result of using hgh fragment 176-191, but side effects should subside following administration.
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