I found some interesting articles on hormonal breast enlargement and I thought I would share. Sorry if this has been covered before:
And there are studies in the references at the bottom. The articles nicely explain the various hormones and other factors involved in breast development.
Estrogen and progesterone play a major part, but what's new to me is that IGF and HGF (hepatocyte growth factor) are major too, not minor. It references a study on using estrogen to enlarge breasts, which found that the only women who grew from estrogen were those whose bodies responded to the estrogen by making IGF. HGF plays a major role too, and IGF+HGF is more effective than IGF alone. Furthermore those who don't make enough IGF are able to grow once IGF is supplied. Macromastia means clinically oversized breasts, often H cup and much larger. Those with macromastia have normal estrogen and progesterone, but their breast cells make nearly twice as much IGF and nearly 6 times as much HGF. In fact taking the stromal cells (connective tissue cells) from the breasts of someone with macromastia and putting them among normal breast cells induces macromastia in the normal breast cells, which might be from the IGF and/or HGF that the macromastia stromal cells make:
Even in those who merely have large breasts IGF tends to be a bit higher than normal. And breasts that make little IGF is one possible cause of being small chested, even when estrogen is increased.
Both IGF and HGF are local hormones which is why breast cells make them in response to estrogen; so that they may be used locally. Both cause general tissue growth where they are applied. i.e., they aren't just for boobs, they're for any tissue. IGF is insulin like growth factor. Insulin is a storage hormone not only for sugar, but also for protein and fat. I am not sure how IGF is similar or different from insulin. In fact IGF is popular in bodybuilder forums for storing protein in muscles. HGF results in cell multiplication and so often increases in response to injury. Both benign and cancerous tumors are likewise accompanied by greatly increased HGF levels. So both lead to growth wherever they are present and would have to be spot applied, not taken orally. There is some concern that they may lead to increased cancer risk, especially HGF as it can make cells multiply faster.
For sources of IGF I found IGF injections, deer antler velvet IGF spray, cinammon and to a lesser extent fenugreek:
However while I found examples of NBE using IGF injections and deer antler velvet IGF spray, I couldn't find anything for cinnamon.
Here's what I found for IGF injections
A user's girlfriend got tremendous growth in her breasts and butt (mainly the butt) in only a couple weeks. Other posters are confused because they assumed IGF is only for muscle.
Deer antler velvet is also popular for NBE.
For HGF the only way I found to increase it was Nadroparin:
It can actually lead to nearly a 6 fold increase, same as what is found in macromastia. So in theory with IGF injections and nadroparin one could induce macromastia. In theory; I didn't find any studies testing this out.
In case it isn't clear already, these are all powerful and dangerous hormones that shouldn't be taken lightly. That is why they can be so effective so fast. The same bodybuilders that abuse IGF are the type who abuse steroids too. From what I can tell it seems safer than other hormones, but not without risk. I was surprised to find that, unlike testosterone and estrogen, it is legal for a random person to own IGF:
It is banned in sports though that's poorly enforced and many athletes abuse it.
Nadroparin is used to prevent clotting after surgery. There is some discussion in the article about converting it to another molecule to get the HGF generating effect without the dangerous side effects of the drug. As mentioned there is also the concern of HGF itself possibly promoting cancer. However nadroparin is routinely used after cancer removal surgery so it most not be nearly as dangerous as estrogen:
During breast cancer OTOH any source of estrogen is to be avoided and anti-estrogen drugs are often used.
While I found examples of using IGF for breast enlargement, I couldn't find anything for HGF. Unlike other hormonal drugs, breast enlargement is not listed among the side effects for nadroparin. It could be that IGF is much more important and/or that HGF merely enhances the effects of IGF.
As for applications, first be careful in messing with any of this. Read up on the proper dosages and any possible negative effects first, being especially wary with the pure hormone or drugs. Second it may be a good idea to include deer antler velvet or maybe cinammon oil in an NBE program, alongside the usual herbs for estrogen, progesterone and anti-testosterone. Because those whose bodies don't make enough IGF could be stuck and unable to grow without it, and even those who do make IGF might benefit tremendously from more. It should be applied directly to the breast and/or butt, not taken orally. Third I don't know a practical way to increase HGF (not without thinning your blood with a prescription-only drug), so that could be something to research further. Though HGH, IGF and estrogen may help increase the body's production of HGF. Likewise I found mixed information on deer velvet and minimal information on cinnamon. How well they actually help IGF would be something to look into.
Straight male into nutrition and herbs.
A good NBE program: http://www.breastnexus.com/showthread.php?tid=23076
IGF and NBE: http://www.breastnexus.com/showthread.php?tid=27347