# Can I eat an olive oil soap?

**URL:** <https://boards.straightdope.com/t/can-i-eat-an-olive-oil-soap/817988>\
**Category:** Factual Questions\
**Created:** [July 16, 2018, 4:34am UTC](https://boards.straightdope.com/t/can-i-eat-an-olive-oil-soap/817988 "2018-07-16T04:34:18Z")\
**Posts on this page:** 9\
**Page:** 1

<div class="post-metadata">

**Author:** ![susan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/susan/32/17537_2.png) [@susan](https://boards.straightdope.com/u/susan)\
**Post date:** [July 16, 2018, 4:34am UTC](https://boards.straightdope.com/t/can-i-eat-an-olive-oil-soap/817988/1 "2018-07-16T04:34:18Z")

</div>

Don’t need answer fast. I’m looking at Kiss My Face Olive Oil Bar Soap, which claims to be 86% olive oil, made with only 3 ingredients (listed below), and fragrance-free. I’m not asking if I ought to eat soap, but whether a soap that contains only Sodium Olivate (Saponified Olive Oil), Aqua, and Sodium Chloride (Sea Salt) is edible, for values of “edible” that include “not harmful” (though not necessarily “tasty”). I suppose another way to ask it is whether saponification makes olive oil inedible.The description doesn’t identify the method of saponification.

---

<div class="post-metadata">

**Author:** ![Ignotus](https://avatars.discourse-cdn.com/v4/letter/i/ecc23a/32.png) [@Ignotus](https://boards.straightdope.com/u/Ignotus)\
**Post date:** [July 16, 2018, 4:41am UTC](https://boards.straightdope.com/t/can-i-eat-an-olive-oil-soap/817988/2 "2018-07-16T04:41:59Z")

</div>

Sure; just wash it down with plenty of vinegar! 😉

(Seriously, soap is very alkaline, and will probably make you throw up if consumed in its raw state. Mixing it\* thoroughly\* with an acid might make it more prone to stay in your stomach.)

---

<div class="post-metadata">

**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\
**Post date:** [July 16, 2018, 4:56am UTC](https://boards.straightdope.com/t/can-i-eat-an-olive-oil-soap/817988/3 "2018-07-16T04:56:34Z")

</div>

> [@susan](#):
>
> The description doesn’t identify the method of saponification.

The method doesn’t matter. Saponified olive oil is not olive oil, any more than chlorine is the same as salt. Saponification is the process that removes the very thing (glycerol) that makes oils oily.

---

<div class="post-metadata">

**Author:** ![Ignotus](https://avatars.discourse-cdn.com/v4/letter/i/ecc23a/32.png) [@Ignotus](https://boards.straightdope.com/u/Ignotus)\
**Post date:** [July 16, 2018, 4:59am UTC](https://boards.straightdope.com/t/can-i-eat-an-olive-oil-soap/817988/4 "2018-07-16T04:59:39Z")

</div>

> [@Dr.Strangelove](#):
>
> The method doesn’t matter. Saponified olive oil is not olive oil, any more than chlorine is the same as salt. Saponification is the process that removes the very thing (glycerol) that makes oils oily.

Not so sure. The pure fatty acids I handled in chemistry class in college seemed pretty oily to me!

---

<div class="post-metadata">

**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\
**Post date:** [July 16, 2018, 5:08am UTC](https://boards.straightdope.com/t/can-i-eat-an-olive-oil-soap/817988/5 "2018-07-16T05:08:11Z")

</div>

Oilier, then :).

---

<div class="post-metadata">

**Author:** ![Ignotus](https://avatars.discourse-cdn.com/v4/letter/i/ecc23a/32.png) [@Ignotus](https://boards.straightdope.com/u/Ignotus)\
**Post date:** [July 16, 2018, 6:13am UTC](https://boards.straightdope.com/t/can-i-eat-an-olive-oil-soap/817988/6 "2018-07-16T06:13:32Z")

</div>

Let’s do some stoichiometry on this soap bar, shall we? Let’s assume it weighs 100 g. Let’s take the given percentage (86%) of olive oil at face value; and let’s further assume that it’s all oleic acid (MW=282 g/mol). That’s 0.3 mol right there. Now, it’s delivered as sodium salt; but let’s assume that we neutralize it with concentrated hydrochloric acid (nothing I as chef would recommend; but let’s do it anyway :)). That would give us 0.3 mol = 18 g of sodium chloride (table salt). Now, the real question is this: can you swallow a mixture of some 80 grams of olive oil and 18 grams of salt without vomiting?

18 grams is a _huge_ amount of salt; but I guess I could down a spoonful or two of the mix, which in its totality would fit readily in a teacup.

---

<div class="post-metadata">

**Author:** ![DavidwithanR](https://avatars.discourse-cdn.com/v4/letter/d/3bc359/32.png) [@DavidwithanR](https://boards.straightdope.com/u/DavidwithanR)\
**Post date:** [July 16, 2018, 6:22am UTC](https://boards.straightdope.com/t/can-i-eat-an-olive-oil-soap/817988/7 "2018-07-16T06:22:22Z")

</div>

The easy, straightforward answer is “No, there’s practically no olive oil in the finished soap.”

And the saponification method was almost certainly to mix it with lye (sodium hydroxide), because it’s a hard bar of soap. If you use potassium hydroxide, you usually get a much softer soap.

---

<div class="post-metadata">

**Author:** ![Arkcon](https://avatars.discourse-cdn.com/v4/letter/a/96bed5/32.png) [@Arkcon](https://boards.straightdope.com/u/Arkcon)\
**Post date:** [July 16, 2018, 11:11am UTC](https://boards.straightdope.com/t/can-i-eat-an-olive-oil-soap/817988/8 "2018-07-16T11:11:22Z")

</div>

> [@Dr.Strangelove](#):
>
> The method doesn’t matter. Saponified olive oil is not olive oil, any more than chlorine is the same as salt.

This is the answer, to this and any other “pica” questions.

> [@](#):
>
> Saponification is the process that removes the very thing (glycerol) that makes oils oily.

As was pointed out, this is not correct, but that doesn’t invalidate the previous correct statement.

I felt like jumping in and summarizing, before this became a multi-page thread of random chemistry.

The chemical reaction we like to call saponification has changed the glycerl fatty acid triester into monoester fatty acid salts, which we call soaps. They’re not the same as olive oil anymore. Broken apart, part of the molecule gone, another thing taking its place, we call that chemistry. And its serious business™.

All soaps and detergents are at least somewhat damaging to internal tissues, regardless of the source. The olive oil starting point doesn’t change the final properties.

And please don’t drink the stoichiometric amounts of hydrochloric acid and sodium hydroxide, and say, “It all averages out to table salt at the end. Burns a bit, going down, 'tho.”

That’s just not cool.

---

<div class="post-metadata">

**Author:** ![susan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/susan/32/17537_2.png) [@susan](https://boards.straightdope.com/u/susan)\
**Post date:** [July 17, 2018, 3:26am UTC](https://boards.straightdope.com/t/can-i-eat-an-olive-oil-soap/817988/9 "2018-07-17T03:26:00Z")

</div>

> [@Ignotus](#):
>
> Now, the real question is this: can you swallow a mixture of some 80 grams of olive oil and 18 grams of salt without vomiting?

Duuude, I wouldn’t eat it all at once.

Thanks for the explanations, all. This question arose while organizing a box of earthquake supplies.
