[Dean's World] Dean: Trans Fats

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Posted by Dean:
Trans Fats
http://www.deanesmay.com/posts/1165346883.shtml


   Will Hinton notes that New York City has [1]banned use of food
   products containing trans-fatty acids in New York.

   I actually know a good bit about this as I used to make a great study
   of fats and heart disease. There is some reason, for example, to doubt
   that cholesterol is really all it's cracked up to be in heart disease.
   Also there's lots of reasons to believe that the demonization of fats
   in general (popular in the 1990s) was way off-base. Then the
   demonization of fats turned mostly to saturated fats. Which is also
   starting to look off-base.

   What's left appears to be trans-fats, and what studies I've seen (it's
   been a few years, but peer reviewed studies typically take a few years
   to percolate up to public attention anyway if they're any good) was
   that, regardless of its impact on cholesterol in general, trans-fatty
   acids looked to be directly associated with heart disease and other
   problems to a level that neither saturated nor unsaturated fats really
   were.

   A quick lesson:

   Fat is a complex molecule made up mostly of hydrogen and carbon. The
   hydrogen tends to be on the "outside" of the molecule, wrapping around
   the carbon atoms on the "inside" of the molecule. Think of it sort of
   like a burrito, with a hydrogen tortilla wrapped around a carbon
   filling. (Yes I'm oversimplifying, and any of you chemistry buffs who
   try to pedantically "correct" my simple analogy will promptly receive
   a virtual wedgy. You've been warned.)

   An "unsaturated" fat basically has lots of holes in the hydrogen
   burrito wrapping. There's spots on the molecular chain where lots more
   hydrogen would fit, but it's not there. Think of it like holes in the
   tortilla.

   Unsaturated fats are very common in fish oils and vegetable oils. They
   tend to be pale yellowish or white or clear, and to be liquid at room
   temperature, and to go rancid fairly quickly, especially if exposed to
   light and heat.

   In a saturated fat, all or most of the "holes" in the hydrogen
   tortilla wrapping are filled with hydrogen. Thus it is more
   "saturated" with hydrogen. The more saturated a fat gets, the whiter
   it tends to get, and the more solid it tends to be at room
   temperature. Butter is mostly made up of highly saturated fats, and is
   goopy but semi-solid at room temperature. Some butters are a little
   more saturated than others, and are thus a little more solid at room
   temp than others.

   A truly highly saturated fat, like beef or pork fat, can be pretty
   solid even at room temperature. Saturated fats tend to go rancid
   slowly--you can leave bacon grease or butter sitting out on your
   counter for days or even weeks at a time and keep using it just fine.

   Polyunsaturated and monosaturated fats are basically unsaturated fats
   by the way. Monosaturates are a little more hydrogen-filled and thus
   keep better than polyunsaturates. Olive oil is a monosaturated fat--it
   tends to keep longer and go rancid less quickly than most vegetable
   oils for this exactly reason. This is also why most people find it a
   little taster.

   Oh, and by the way, in case you never realized it: yes, vegetable oil,
   fish oil, bacon grease, butter, and similar products are basically all
   nothing but fat. If you look at a tablespoon of olive oil you're
   looking at, chemically, a tablespoon of fat with only a tiny smidge of
   other things in it giving it a little color and flavor. If you're
   looking at a stick of butter you're looking at a stick of solid fat
   with a tiny smidge of flavor agents and a tiny amount of protein and
   carbohydrate.

   When you're using these ingredients in your cooking, you're adding
   fat. It's what you're doing. These products do not "contain fat," they
   basically are fat. When you smear butter on your bread you're
   basically saying, "this would taste better with some fat on it."
   (Ditto if you substitute olive oil, shmaltz, or even mayonnaise. These
   are all products made of almost nothing but fat with a little
   flavoring.)

   Saturated fat is more expensive than unsaturated fat. It comes mostly
   from meat and dairy products). It's also better to cook with,
   especially to fry with. And, it keeps longer in the fridge or even on
   the counter.

   OOOOOKay, so, now, what the heck is a trans-fat? Actually it's really
   simple when you get all of the above:

   Take some cheap vegetable oil, and whip it heavily with hydrogen. The
   little holes in the hydrogen tortilla wrapping of the fat molecules
   start to fill up. It begins to whiten up, to harden... and to take on
   the characteristics of an animal fat. Of a saturated fat.

   It was first made popular in a product known as [2]Crisco. Which is
   basically cheap cottonseed oil whipped with hydrogen until it takes on
   the physical qualities of butter.

   Most forms of margarine are the same way: take some cheap vegetable
   oil, whip in a bunch of hydrogen and some yellow eye to make it look
   like butter, and voila, a product that looks like butter.

   This is what is known as "hydrogenated" or "partially hydrogenated"
   oil.

   So what's the big deal? Well, fat molecules come in many different
   shapes and lengths. An unsaturated vegetable oil whipped with hydrogen
   does not result in a molecule that looks like pork fat or butterfat.
   It's its own unique molecule, quite unlike anything found in nature.
   And many of those molecules are better known as trans-fatty acids.

   Small amounts of trans-fats exist in nature, but really only in tiny
   quantities. When you're eating partially hydrogenated oils, however,
   you're eating great huge quantities of it. Far more than any of our
   ancestors ever would have.

   You're basically eating a chemical additive which was never really
   tested before being released into the general population.

   Got a jar of Crisco anywhere in your house? It's nothing but a
   chemistry experiment from the early 20th century. It's a jar full of
   trans-fat.

   How did it get past FDA approval? Well, it was available before there
   was any FDA, for one thing. Besides, who'd think whipping air into
   vegetable oil would make something unhealthy?

   It's increasingly looking like most of the health warnings we had
   about fats in the 1990s, and the shift to saturated fats later on, was
   off-base. It was the ubiquitous presence of trans-fats, which in even
   small quantities look to have major health implications. Not if you
   just eat a little now and then, but if you eat it every day for
   decades it's going to cause problems.

   And until very recently, partially hydrogenated oils were in almost
   EVERY manufactured food. Breads, cereals, chips, margarines, sandwich
   spreads, salad dressings, and more. To give on an idea why:

   If you've ever made your own potato chips at home, you've probably
   noticed that when you fry the chips in vegetable oil, they come out
   kind of greasy and oily. That's because if you made it in vegetable
   oil, the remaining oil was still liquidy and tended to seep slowly out
   of the chips.

   If you made them with animal fat--beef or pork fat, say--once they
   cooled they didn't drip at all. Why? Beef and pork fat is pretty solid
   at room temperature, and doesn't tend to rub off on your fingers so
   much.

   Animal fat costs a lot more than vegetable fat. So what did
   manufacturers do? Used cheap hydrogenated oil of course!

   And by the way, does that mean those companies were evil? I sure don't
   think so. Gee, you've got a nice cheap product that results in a
   pleasing potato chip. Using a product that's been around for decades
   that no one ever suspected was unhealthy. Why not? It's just Crisco
   for goodness sakes!!

   I'm not looking forward to the lawsuits here--I don't think many
   companies deserve to be kicked around for using what they honestly
   thought was a good and reliable and cost-effective product. But I do
   think this is a very good example of where sensible government
   intervention is a good thing. There are many perfectly acceptable
   alternatives to partially hydrogenated oils now, that result in more
   molecularly natural foods. Food vendors should be pushed into using
   them.

   And if the pro-Crisco lobby wants to lobby for "freedom of trans-fat
   choice!" then more power to 'em. Just get the stuff out of products
   that I might unsuspectingly buy on the streets, or that poor people
   might wind up eating just because they don't know better and/or they
   have no alternatives.

References

   1. http://www.goodwillhinton.com/new_york_city_to_ban_trans_fats_at_restaurants
   2. http://en.wikipedia.org/wiki/Crisco