Estrogen – the evil hormone. At least that’s what some would have you believe. Many, way off the mark supplement companies have been promoting “estrogen blockers” as a way to build muscle and burn fat. The problem with companies selling this bill of goods is that they have barely a surface understanding of hormonal chemistry – just enough ‘understanding’ to get it all wrong. Not surprising huh?

Blocking estrogen has never shown an improvement in lean muscle. And pharmaceutical compounds like Nolvadex have always seemed to reduce the effectiveness of anabolic steroids when taken together. Is there a connection?

A recent study in the Journal of Biological Chemistry has revealed the mechanisms by which estrogen promotes a decrease in fat cell size and overall fat mass.

This study showed that estrogen replacement reduced fat by promoting the use of fats as fuel. The reduction of fat was accomplished through three mechanisms: inhibiting fat storage in muscle tissue, in fat, and in the liver, triggering pathways that promote fat burning in muscle tissue, and breaking down existing fat for energy.

See Also:
“Super-Slow” Weight Training Versus Conventional Weight Training and The Effects on Energy Expenditure

In the presence of estrogen, the expression genes that govern manufacturing and storing of fat was reduced, and the expression genes that promote burning of fat in muscle was increased.

This backs up a 2000 study that concluded, “it appears that estrogen enhances one’s ability to burn excess fat in both males and females.”

In this study, blocking one type of estrogen receptor (basically stopping the effects estrogen) caused the control subjects to expend less energy and created larger stores of fat while consuming the same caloric intake.

Estrogen is sounding like quite an effective fat burning hormone. However, don’t misunderstand these findings. Excessive estrogen is not a good thing. What this and other studies show is that reducing normal estrogen levels can actually impede fat loss. So blocking estrogen production or effect may only be desirable in a higher than normal estrogen environment.


Your question was successfully sent! It will be answered shortly.

5 + 2 =

Estrogen a Fat-Burner?

by Paul Delia time to read: 2 min