Contraception and Caffeine

Dear Apologists:
My graduate class in Catholic Ethics was discussing the topic of contraception. I made (perhaps not the greatest argument for our prohibition) an Essentialist argument, claiming that contraception is an intentional thwarting of the natural end for sex, that it is voluntary bad health to contracept.
A Calvinist friend of mine answered that taking caffeine in order to stay awake (for legitimate reason) is an altering of the body’s natural function, and is - by the same measure - voluntary bad health.
The only thing I could answer was that with caffeine, certain obligations (which require our being awake) may represent a competing moral claim to the claims nature has on us; in contraception, there are no such competing moral claims. Also, our sleep cycle can be altered simply through human will, and therefore is somewhat already under our purview naturally, not so contraception. However, I found these arguments somewhat weak.
Is there a better answer to his objection, on his terms?
Thank You,

His argument would apply to eating food, because the natural function of the body would be to die if we don’t eat. Right? It would seem that being awake is not placing the body in an unnatural condition, which caffeine could effectively do if necessary. Both being awake and sleeping are natural functions. Ingestion of many beverages or foods give the body energy (caffeine more so than others in the short-term). Eating and drinking are natural to human behavior also. If that causes you to need less sleep, there’s nothing unnatural replacing sleep. On the other hand, if one abused caffeine, just like any other addiction or something that induced excessive bodily harm, then yes, it could be sinful.

The thing also with the sexual faculties is that it is the natural law to recognize ourselves as created beings of two genders. The fact that procreation is tied into the function of the sexual faculties reflects the creative power of whatever “Creator” ordered the two genders. That power is only ignited when joined to the other gender. If one agrees that sexuality is a “gift,” and that its function makes sense only in the context of giving it to the complementary gender, then one understands why anything outside that use is an affront to the gift-giver. Sexuality differs from our other gifts in this way.

Drinking coffee is not wrong, but if that’s all you drank every day, you would become dehydrated and would cause serious harm to your body. This would be a sin.

Taking some medication can make you drowsy, thus interupting the natural order. But this in itself is not sinful. But if you misuse it and take too much, it could put you to sleep for good.

Why is gluttony a sin? You take something which is essential for survival and misuse it.
In some instances this involves taking nutrients into our body which are necessary for us and then purge them out of our bodies (vomiting). In essence, this denies the body the use of the nutrients in the way they were intended.

Sex is not evil. It is necessary for procreation and the survival of humanity.
In the case of contraception, it takes something which is essential for survival and then denies that function in the way that it was intended.

Hope this is helpful.

Contraceptive sex is sex that is contrary to the purpose of sex: procreation.

Drinking caffeinated beverages is not contrary to the purpose of drinking. The purpose of drinking is not to fall asleep.

It is not that anything that changes how the body functions is wrong. Neither is it that the controlling birth spacing or such is wrong. For instance, the Church does not have a problem with medical treatments that have as an unintended side effect the suppression of fertility, and does not require abstinence while on those treatments. This is because such do not involve the explicit denial of what sex is.

The best I can do to make up a parallel involving caffeine and sleeping is that it would be like purposefully removing the rest and regenerative purposes from sleep because we like sleep better that way for some reason. This would clearly be unhealthy, and is worlds away from staying awake for another hour or two.

Thank You! The comments have been helpful.

It seems like the consensus is:
There is an Essentialist answer, because the inherent purposes of eating and drinking could include the ingestion of things to maintain wakefulness, especially because all eating and drinking is meant to give the human being either short or long term energy (and it would seem that there is no philosophical limit on how long or short that energy should last).
Also, the purpose of the Circadian Rhythm does not seem to be a biologically unalterable law of when you should be awake and when you should be asleep; its purpose seems to be supporting the human being so that he or she can be awake when he or she needs to be.

By contrast, actively refusing one of the inherent purposes of intercourse, is obviously a rejection of its inherent purposes.

I suppose he would say, “Doesn’t caffeine refuse one of the purposes of Circadian Rhythm?” I suppose the answer, from this perspective, would be “The Circadian Rhythm is supposed to be malleable.” And this makes sense to me.

Obviously, people always had some kind of control (I guess the will power thing or exercise or stress) over their Circadian rhythm. People don’t have any kind of natural ability to get infertile, so taking something to effect infertility would be different from taking something to affect fatigue.

Thanks everyone!

DISCLAIMER: The views and opinions expressed in these forums do not necessarily reflect those of Catholic Answers. For official apologetics resources please visit