# Oils - is lower freezing point healthier? **URL:** \ **Category:** Factual Questions\ **Created:** [January 17, 2014, 6:39am UTC](https://boards.straightdope.com/t/oils-is-lower-freezing-point-healthier/679049 "2014-01-17T06:39:03Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![AaronX](https://avatars.discourse-cdn.com/v4/letter/a/7bcc69/32.png) [@AaronX](https://boards.straightdope.com/u/AaronX)\ **Post date:** [January 17, 2014, 6:39am UTC](https://boards.straightdope.com/t/oils-is-lower-freezing-point-healthier/679049/1 "2014-01-17T06:39:03Z")
Ok, here’s the logic: [ol] [li]Saturated fats are unhealthier than unsaturated[/li][li]Saturated fats also have higher freezing points (freeze more easily)[/li][/ol] But is this true for blends / oils within each category? If I have stew A and curry B, and 'fridgerate both of them, and the layer of oil on A solidifies but on B it remains liquid, are the fats in B healthier? Can I use this method to compare foods? To separate unhealthy fats? ---
**Author:** ![AaronX](https://avatars.discourse-cdn.com/v4/letter/a/7bcc69/32.png) [@AaronX](https://boards.straightdope.com/u/AaronX)\ **Post date:** [January 19, 2014, 5:03am UTC](https://boards.straightdope.com/t/oils-is-lower-freezing-point-healthier/679049/2 "2014-01-19T05:03:52Z")
Ok, nobody’s wondered this before? No information? ---
**Author:** ![BrightNShiny](https://avatars.discourse-cdn.com/v4/letter/b/7bcc69/32.png) [@BrightNShiny](https://boards.straightdope.com/u/BrightNShiny)\ **Post date:** [January 19, 2014, 6:29am UTC](https://boards.straightdope.com/t/oils-is-lower-freezing-point-healthier/679049/3 "2014-01-19T06:29:59Z")
Here’s a [Straight Dope](http://www.straightdope.com/columns/read/694/why-is-palm-oil-bad-for-you) article that has some info: > [@](#): > > Cholesterol as such is found only in animal products. But saturated fats, which (some feel) can produce high blood cholesterol levels in humans, can be found in many things, notably “tropical” oils such as palm and coconut. > > Nontropical oils, such as corn, soy, and safflower, are high in polyunsaturated fats, which reduce blood cholesterol. Why are tropical oils different? Because they come from more forgiving climates. Vegetable oils are a major component of plant cell membranes. But they’ve got to stay liquid to work, and saturated fats congeal when cold. To avoid this, plants in northern climates have to produce unsaturated fats, which don’t congeal. That takes extra energy. Tropical plants, though, can get by with the saturated stuff, which is easier to make. So, from that, I gather that you can separate out saturated vs. unsaturated by freezing point. That’s the only info I have. Somebody more knowledgeable will have to add further info. ---
**Author:** ![thelurkinghorror](https://avatars.discourse-cdn.com/v4/letter/t/7c8e57/32.png) [@thelurkinghorror](https://boards.straightdope.com/u/thelurkinghorror)\ **Post date:** [January 19, 2014, 8:39am UTC](https://boards.straightdope.com/t/oils-is-lower-freezing-point-healthier/679049/4 "2014-01-19T08:39:27Z")
I use 5w30 in my car because it works better at lower temperatures but also is recommended. But anyway, fractional freezing of fats, interesting. Maybe you can make a super-healthy food applejack? Ghee is clarified butter made by scraping off the floaters (but while heating not freezing). I am having a hard time finding stuff that is not Ayurveda woo however. Should one expect that lower freezing point = lower melting point for fats? ---
**Author:** ![njtt](https://avatars.discourse-cdn.com/v4/letter/n/ecd19e/32.png) [@njtt](https://boards.straightdope.com/u/njtt)\ **Post date:** [January 19, 2014, 10:31am UTC](https://boards.straightdope.com/t/oils-is-lower-freezing-point-healthier/679049/5 "2014-01-19T10:31:38Z")
You are ignoring the factor of fatty acid chain lengths, which can vary widely, and which, I am pretty sure, have a much larger impact on the freezing point of the fat than whether it is saturated or unsaturated. Your point **1** is an oversimplification. (Even ignoring the trans/cis issue, and mono versus polyunsaturates, I doubt that a diet without _any_ saturated fats would be healthy.) Your point **2** is only true for fats of the same chain length, and different fats do not have the same (average) chain length. (Furthermore, fats from natural sources will contain chains of many different lengths, and I should not be surprised if the particular proportions in the mixture influence freezing point as well as the overall average length.) ---
**Author:** ![AaronX](https://avatars.discourse-cdn.com/v4/letter/a/7bcc69/32.png) [@AaronX](https://boards.straightdope.com/u/AaronX)\ **Post date:** [January 24, 2014, 5:29am UTC](https://boards.straightdope.com/t/oils-is-lower-freezing-point-healthier/679049/6 "2014-01-24T05:29:27Z")
> [@njtt](#): > > You are ignoring the factor of fatty acid chain lengths, which can vary widely, and which, I am pretty sure, have a much larger impact on the freezing point of the fat than whether it is saturated or unsaturated. > > Your point **1** is an oversimplification. (Even ignoring the trans/cis issue, and mono versus polyunsaturates, I doubt that a diet without _any_ saturated fats would be healthy.) > > Your point **2** is only true for fats of the same chain length, and different fats do not have the same (average) chain length. (Furthermore, fats from natural sources will contain chains of many different lengths, and I should not be surprised if the particular proportions in the mixture influence freezing point as well as the overall average length.) Hmm, good point about chain length/MW. But I think chain lengths are slightly uniform, otherwise they wouldn’t be able to say saturated fats freeze more easily. I should go find out chain lengths of various fats.