Talk:Fat
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[edit] Saturation Inaccuracy
This section of the artcile says: "A fat's constituent fatty acids may also differ in the number of hydrogen atoms that branch off of the chain of carbon atoms. Each carbon atom is typically bonded to two hydrogen atoms. When a fatty acid has this typical arrangement, it is called "saturated", because the carbon atoms are saturated with hydrogen; meaning they are bonded to as many hydrogens as they possibly could be. In other fats, a carbon atom may instead bond to only one other hydrogen atom, and have a double bond to a neighboring carbon atom. This results in an "unsaturated" fatty acid. A fat containing only saturated fatty acids is itself called saturated. A fat containing at least one unsaturated fatty acid is called unsaturated, and a fat containing more than one unsaturated fatty acid is called polyunsaturated."
All right, I'm not too sure how to go about this without it sounding too complicated. First off, I think I'll need to define the difference between "monounsaturated" fatty acid and "polyunsaturated" fatty acid since it will be needed eventually anyways. So this part that says: "a carbon atom may instead bond to only one other hydrogen atom, and have a double bond to a neighboring carbon atom. This results in an "unsaturated" fatty acid." That would be an unsaturated fatty acid, yes. More specifically though, that would be a "monounsaturated" fatty acid. A "polyunsaturated" fatty acid would have MORE than 1 double bond. This may not sound so significant but it is important information for what I will get into.
This part says: "A fat containing only saturated fatty acids is itself called saturated." This is where it gets tricky. You see, a fat is generally synonymous with triglyceride within this body. However, fat within food encompasses all fatty acids regardless where they come from. Therefore, to say that a saturated fat is a fat containing only saturated fatty acids would be inaccurate. If that was referring to fat as a triglyceride, well then, triglycerides are not measured in such a way. Even though a triglyceride can certainly have all 3 of its fatty acids be saturated, it still would not be called a "saturated fat" or even a "saturated triglyceride". I'll further demonstrate this point. This other part says: "A fat containing at least one unsaturated fatty acid is called unsaturated, and a fat containing more than one unsaturated fatty acid is called polyunsaturated." Polyunsaturated is not defined by how many of the fatty acids are unsaturated in a fat. However, that statement leads me to believe it is referring to triglycerides. I mean, if you think about, if you have 900 fatty acids in a source of fat, what are the chances of all of those fatty acids being unsaturated? So if 899 of them were and 1 was saturated, then it could not be defined as a polyunsaturated fat? Then again, if it is indeed referring to triglycerides then I still stand by what I said earlier, that triglycerides are not measured in saturation. Only a source of fat is. I'll try to clairfy myself a bit more still. This part says: "a fat containing more than one unsaturated fatty acid is called polyunsaturated." Well, what if it only had a single unsaturated fatty acid but it was actually a polyunsaturated fatty acid, would it still only be considered an unsaturated fat?
When it comes to defining fat as saturated, monounsaturated, or polyunsaturated, it does not refer to fat as triglyceride. Instead, it only refers to fat as all the fatty acids within a source. Therefore, such definitions are not used when referring to the triglycerides within ones body, it's only used when speaking of food, more specifically, on food labels. In which case, I'll tell how it would be defined.
- Saturated Fat - The amount of Saturated Fatty Acids within a source of Fat.
- Monounsaturated Fat - The amount of Monounsaturated Fatty Acids within a source of Fat.
- Polyunsaturated Fat - The amount of Polyunsaturated Fatty Acids within a source of Fat.
I guess my argument is that, if triglycerides really are defined by their saturation, why are they defined in terms of "saturated, unsaturated, and polyunsaturated" while fatty acids are defined in terms of "saturated, monounsaturated, and polyunsaturated"? Furthermore, why would it still be referred to as fat when it's obvious that such naming would cause confusion with the food labeling system? That's why I believe that triglycerides are NOT named in terms of their saturation and only fat in general is! (Fat in general meaning the term used on food labeling which encompasses all fatty acids.) And the person who wrote that stuff may have had some confusion on how such things are properly defined.
Therefore, I am changing that section of the article to: "A fat's constituent fatty acids may also differ in the number of hydrogen atoms that branch off of the chain of carbon atoms. Each carbon atom is typically bonded to two hydrogen atoms. When a fatty acid has this typical arrangement, it is called "saturated", because the carbon atoms are saturated with hydrogen; meaning they are bonded to as many hydrogens as they possibly could be. In other fats, a carbon atom may instead bond to only one other hydrogen atom, and have a double bond to a neighboring carbon atom. This results in an "unsaturated" fatty acid. More specifically, it would be a "monounsaturated" fatty acid. Whereas, a "polyunsaturated" fatty acid would be a fatty acid with more than 1 double bond."
I don't think it is necessary to get into how to define a Saturated Fat, Monounsaturated Fat, and Polyunsaturated Fat. Maybe that'd be better a an artcile on Food Labeling or something along those lines. Well, I hope I articulated myself well enough and was not too confusing. It's late, I probably spent more time than necessary to explain all this. Aw man, please give good reason if you disagree with me. My main source of this information is ACE Personal Trainer Manual 3rd Edition. It talks about that stuff in Chapter 4 Nutrition. Jamesters 07:35, 25 September 2006 (UTC)
[edit] Theory
Huh? The human body burns fats to supply the energy to contract and relax muscles (whereas the electrical energy needed for neural activity is provided by burning carbohydrates). Unfortunately what seems to have been overlooked, is that humans come in two types with two types of 'engine'. Those with an 'engine' which can burn either type of fat and those whose 'engine' is tuned to run at its most efficient on animal fat alone. How do you tell which type of 'engine' your body has? If you have the former, you get an equal pleasure response when you eat either butter (an animal fat) or margarine (a vegatable oil) and if you are the later you prefer the taste of butter. There is an actual difference in physical response too. The former salivate over the taste of either fat and the later only salivate over the taste of animal fat. Because the latter type run on animal fat and animals come in two types, diurnal and nocturnal, this has led to all the weight problems. People who have weight problems prefer the taste of animal fats and have been advised to eat the lower caloried vegetable fats because they have put on weight when they ate the food they preferred. That was the wrong answer! They two fall into two catagories, diurnal and nocturnal. To find out which, simply ask them when they would prefer to go out for a special meal, lunchtime or in the evening for dinner. Diurnals choose lunch and should never eat after dark and nocturnals choose evening and should only eat after dark. Were they to only eat the food the like at those times of day, they have as perfect a 'built-in' weight control system as any of the former type with the bodies tuned to run on either type of fat, i.e. thin people.
That sounds like a crackpot theory from some weight-loss author; do you have any evidence that this is actually accepted by real biochemists? --LDC
I let it remain on the page because i had never heard of _that_ strange theory before, and there are a couple of actual factoids in it...I'll extract them and add to the article. --Anders Törlind
Animal fat and vegetable fat. Where do you put fats stored by other sorts of living things - fungi and protozoa?
- Is there a chemical difference between these types of fat?
- "Vegetable fats were developed by plants as a means of attracting animals..."
This seems to imply some kind of motive to plants. -- RTC 20:26 Apr 8, 2003 (UTC)
Vegetable fats are developed by plants as a means of attracting animals in need of energy, in order to spread seeds or further pollination.
I disagree with this. and agree with RTC. This comment sounds very very weird to me. ant
[edit] Carbon in fat?
Does fat contain carbon atoms? Brutulf 16:20, Nov 19, 2004 (UTC)
- Almost everything found in the human body contains a carbon atom somewhere. In particular, yes, fat contains carbon. In fact, the distinguishing feature of fatty acids is how many of it's carbon atoms are saturated with hydrogen atoms. Kutulu 12:09, 26 Apr 2005 (UTC)
[edit] Whats up with these unit conversions? They're off by 1000 fold.
"Fat is one of the three main classes of food and, at approximately 38 kJ (9 Cal) per gram, as compared to sugar with 17 kJ (4 Cal) per gram or ethanol with 29 kJ (7 Cal) per gram, the most concentrated form of metabolic energy available to humans."
Cal = calorie correct? and KJ = kilojoule correct?
If so those calorie numbers are missing a 1000x multiplier.
Google for "convert 38 kilojoule to calorie":
38 kiloJoule = 9 082.21797 calorie
- Just different calories. Hardly anybody uses those dinky gram calories or small calories any more. Gene Nygaard 18:55, 20 August 2005 (UTC)
[edit] Obviously wrong
Those values were obviously wrong, yes. So why didn't you just correct them? Be bold! :)Brutulf 22:36, Mar 21, 2005 (UTC)
Edit: Upon closer examination, it seems that there are two ways of writing it, either as kilocalories or just calories (I would prefer kilocalories). Confusing, eh? See calorie. Brutulf 22:49, Mar 21, 2005 (UTC)
[edit] Admins, quick revert needed
Someone vandalized this. Quick revert needed ASAP! --Dungodung 18:13, 5 Jun 2005 (UTC)
The normal short form for writing kilocalories, referring to food energy calories is kCal.
[edit] Exact description of fat needed
This article has perplexed me somewhat in that nowhere, aside from in glib references to individual constituents of it, has the term fat actually been properly defined in terms of what it actually IS, and I was hoping someone could rectify this. I have added a stub notifier to this article until someone can be bothered to address this fairly major problem. 80.177.20.202 03:49, 5 October 2005 (UTC)
- It has many meanings, and the only good description is in technical terms. There are triglycerides, fatty acids, sterols, but "fat" may also refer to adipose tissue. What, specifically, is your concern? JFW | T@lk 07:11, 7 October 2005 (UTC)
[edit] Cleanup
I've added a cleanup tag to warn readers that this article is still well below Wikipedia standards. Much of the text in it sounds like it was copied from an entry-level health-guide booklet, or from a school book written for younger children, and lacks the breath and scientific accuracy desireable for an encyclopedia entry. This article should best be turned into a brief overview of (a) triglycerides, (b) adipose tissue, and (c) the role of fat in human and animal nutrition, and then refer to the relevant more specific articles for further information. Any biologists here interested? Markus Kuhn 16:26, 28 January 2006 (UTC)
- Well, I'm something of a chemist, and I think the bit on the chemistry of triglycerides is pretty clear now. I also added a bit on trans-fats. I don't know beans about biology, though, you'll have to get someone else there. Let me know if my edit was too much. Russell Abbott 08:39, 14 May 2006 (UTC)
- I also merged energy with metabolism, since metabolism is exactly that, and a major subject heading with not even a full line seemed ridiculous. Russell Abbott 09:08, 14 May 2006 (UTC)
[edit] Wiki Technical Question
How does one edit the small right-hand table in the article? I see it's some sort of seperate object referenced on several pages. I was going to add Omega-3 and Omega-6 under polyunsaturated, but realized that I had no idea how those type objects were editted. JeramieHicks 03:01, 30 July 2006 (UTC)
- Nevermind, I found it. It's a template. JeramieHicks 03:38, 30 July 2006 (UTC)
[edit] Movement/Energy
What effect does basic movement have on fat? For example, I read that for a double chin one must "pat" under their chin to firm it up, some people use those vibrating work-out belts to lose weight as well. Is simple movement all that is needed to liquidate fat or is there something more involved? And if movement alone can liquidate fat, at what speeds is it required to have an effect? 71.112.224.112 02:37, 23 September 2006 (UTC)
