Alpha Blockers and Weight Gain

KEY POINTS:

1. Alpha-Adrenergic Blocker therapy appears to be able to lead to weight gain independent of diet and lifestyle factors.


2. Alpha-Adrenergic Blockers also appear to be able to change the hormonal environment of our fat tissue.


3. These observations seem to support the Lipophilia Hypothesis and challenge the Caloric Balance Hypothesis.

The Caloric Balance Hypothesis says that, for a medication to make us gain weight, it must first drive us to eat more calories or burn off fewer calories, and this positive caloric balance then makes us accumulate fat in the fat tissue.

The Lipophilia Hypothesis says that an establishment of a positive caloric balance is a consequence and not a cause of the weight gain. The real cause is the hormonal derangement of the fat tissue itself.

So can we find evidence to test these hypotheses? In particular:

1. Do alpha blockers lead to weight changes independent of factors related to diet and exercise?

2. Can these medications impact the body's hormonal/metabolic ensemble? For instance, can they change insulin sensitivity or otherwise change the ways in which fat tissue metabolism operates?

As to the first point, a rough and not-at-all-comprehensive internet search about alpha adrenergic blockers yields some surprisingly strong support for the Lipophilia conjecture.

1. Consider this article from the December 1998 Journal of Cardiovascular Pharmacology: "Long-term alpha adrenergic blockade attenuates diet-induced dyslipidemia and hyperinsulinemia in the rat."[1]

Now, this article talks about rats, not human beings. But it does suggest that these medications can affect insulin levels.

2. Here's another article that discusses "The effect of the alpha adrenergic blocker, Doxazosin, on endothelial function and insulin action."[2]

3. And here's another article that discusses: "The regulation of plasma insulin level by alpha 2 adrenergic receptors."[3]

4. And here's another yet article on "Insulin inhibition of alpha adrenergic actions in the liver."[4]

Now obviously, our references are relatively arbitrary. But even without delving into the science, the fact that alpha blockers can effect both changes in weight and changes in insulin levels seems to suggest that our alternative hypothesis holds up.

References