Does the Pill Really Cause Weight Gain?

Aug 17, 2011
Bob Yirka

The Pill does NOT cause women to gain weight - tijmen

A research scientist says birth control pills do not cause women to gain weight.

For years women have quit taking the Pill because of the perceived notion that it makes them gain weight. David Grimes, a researcher from the University of North Carolina, in a paper published on Contraception, calls the idea an elaborate mythology, one "fueled by rumor, gossip and poor-quality research."

Why Women Believe the Pill Causes Weight Gain

Grimes can't say for sure why women believe the Pill causes weight gain, but suspects that it has something to do with women as a general rule feeling that anything that messes with their hormones probably causes them to gain weight, or as he implies, but doesn't quite say, women as a group tend to believe a lot of things cause weight gain, that don't.

Of course the fact that women reading the literature that comes with their prescription see the words "weight gain" among the possible side effects, might have something to do with it as well.

How Grimes Knows that the Pill Does Not Cause Weight Gain

Grimes says in his paper that there is currently no evidence of any study that has shown the Pill actually contributes to weight gain. He even goes so far as to suggest that ongoing research indicates that the Pill might actually help women lose weight.

As for why the Pills' label lists weight gain as a possible side effect, Grimes says that it happens, as it does with many drugs, because of the way that trials are conducted when a new drug is about to be released. Those volunteers who take whatever is being tested, in this case, the Pill, are asked about any side-effects they experienced during the trial. Apparently a lot of women in the trial mentioned weight gain, so, the makers of the Pill just slapped it on the label without doing any further research (because of additional expense) to see if it were so.

He also notes that because the Pill is taken over long periods of time, women that gain weight assume it's due to its effects, rather than to other causes. He adds that the average adult puts on about a pound a year no matter whether they take the Pill or not, and thus find it easy to blame the Pill for their weight gain.

Grimes also points out that sometimes something such as weight gain can become a self-fulfilling prophecy. If a woman thinks the Pill will make her put on some pounds, she might just eat more, proving to herself that she was right all along.

Sources

"Measured and reported weight change for women using a vaginal contraceptive ring vs. a low-dose oral contraceptive" Contraception Journal, viewed August 17, 2011.