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wozz
02-06-2003, 12:46 PM
Some of you seem to know your chemistry pretty well.
This is overly simplified, so tell me where I\'m wrong.

Saturated fats are not good for cholesterol levels. Hydrogenating an unsaturated fat makes it saturated. Regardless of whether trans fats are good/bad, hydrogenated oils are saturated. So WTF is the difference?

Second question: I was in the supermarket yesterday I was looking at all the fake butter. There are a lot of them that say \"NO TRANS FATS\" in big letters on their labels. I pick up one of them, and one of the ingredients is partially hydrogenated oil. I pick up the next one and it doesn\'t say that. Is this just all BS or what?

Last question: If one of those fake butters says it contains no saturated fat, and no hydrogenated fat, what is keeping it solid at room temp?

**DONOTDELETE**
02-06-2003, 12:48 PM
Kitchen pixies.

druid
02-06-2003, 02:10 PM
well I know a little on this subject but not much.

For starters satrated fat is a natural fat that your body can metobilze correctly. When an unsaturated fat is hydrogented (which means it is bombared with hydrogen ions) it is tured in to a quasi-saturated fat. It is not quite a satured fat. It is missing some of the hydrogren thingies (sorry for the laymen term -- i think the correct term is hydrogen bonds but not sure).

Your best bet would be to avoid those highly processed (most foods that are highly processed are pretty much junk -- avoid them) imiation butters. Stick with regular butter -- and if your really that worried about saturated fat just remember to eat in moderation.

wozz
02-07-2003, 01:06 PM
Thanks. I\'m not really worried about myself, I don\'t touch any of that crap. I have a genetic disorder called celiac sprue that basically shuts down my digestive system if I eat certain kinds of gluten, and gluten is in EVERYTHING (almost all spices, most lunch meats, etc. I also can\'t lick postage stamps).

I was asking more because my roommate is dieting (Weight Watchers) and basically doesn\'t eat any natural foods (save for meats, and fruits and vegetables etc). She is also extremely uninformed about nutrition (as in if any kind of authority figure says something it must be true) and very unwilling to change any of her beliefs when presented with evidence.

I feel bad for her because she is always tired and gets sick frequently (she is also quite overweight and smokes), and she refuses to believe that nutrition is the root of her problems, which I believe it is.

I know a lot of people like her too. The current nutritional gurus have some how equated healthy with losing weight. My roommate will put a huge amount of fake butter on a piece of toast because it\'s \"healthy\", and she wonders why she only drops a couple pounds per month.

Back to my question though: As I understand it, there are three main types of fat (saturated, and mono/poly unsaturated). Saturated fats have no more room for hydrogen atoms, monounsaturated have room for one more, and polyunsaturated have room for two or more. Only saturated fats are solid at room temp. I don\'t think that hydrogenated fats are \"quasisaturated\", they are fully saturated and have the same chemical shape as a normal saturated fat. The difference is that hydrogenated fats \"fold\" differently and have a different physical shape that normal saturated fats, and this is called a trans fat (I believe the correct term is that they are \"isomers\"). And your body doesn\'t know what to do with them.

So assuming this is all correct, (once again) what is keeping the stuff solid?

And my main question (which is really stumping me) is if something has as one of it\'s ingredients \"partially hydrogenated oil\", how can they say it has no trans fats? I think my question stems from the word \"partially.\" Does that mean that only some of the spaces are filled with hydrogen atoms? If that is true, then once again how is the stuff solid? I\'m pretty sure I\'m correct on that (that only saturated fats are solid at room temp).

Whew! Sorry for the ranting post.

druid
02-07-2003, 02:49 PM
well I called them \"qausi-saturated\" because there is something about about them that makes them different from satutated fats and gets processed differently. And from what i understand about organic chemistry (and is not much) the shape of the molecule makes a huge difference. But I know transfats are solid @ room temperture. When I was in highschool I worked at a fast food resturant and the oil they used for frying was shorting. it was white and solid at room temperture. Also I eat all natural peanut butter (which has no transfats, 2 g saturated fat, and 14g unsaturated fat per serving). And it is oily as hell (despite have some saturated fats in it. but I have no idea what keeps \'em solid.

xvs
02-08-2003, 03:19 PM
http://jchemed.chem.wisc.edu/Journal/Issues/1997/Sep/abs1030.html (\"http://jchemed.chem.wisc.edu/Journal/Issues/1997/Sep/abs1030.html\")

Elana
02-13-2003, 01:03 PM
The stealth fat

Trans fat lurks in a multitude of foods. It’s not labeled. And it’s bad for your heart. Here’s how to avoid it.


HIDDEN TRANS The label on Mrs. Smith’s Apple Pie says a slice contains 3.5 grams of saturated fat (although our test found 3 grams). But our test also found 4 grams of \"invisible\" trans fat, giving the slice more \"bad\" fat than almost any other product in our table Bad fats in common foods. We found hidden trans fat in many other foods, including those shown below.

Many seemingly heart-healthy foods, made with vegetable oils containing little saturated fat and no cholesterol, harbor the most heart-unfriendly fat of all: trans fat, which currently isn’t labeled.

While meat and dairy products naturally contain small amounts of trans fat, the vast majority of trans in the American diet is created artificially by bubbling hydrogen gas through vegetable oil, a process called partial hydrogenation. That transforms some of the oil’s unsaturated fat into trans fat, which helps stabilize the oil (making it useful for deep-frying and for packaged foods) and solidify it (making it suitable for margarine and many baked goods). But in terms of health, trans fat acts like saturated fat, the kind that clogs the arteries.

In July 2002, the National Academy of Sciences’ Institute of Medicine, which advises the government on health policy, made official what many researchers have argued for years: Trans fat worsens blood-cholesterol levels and almost surely increases the risk of heart disease. Indeed, trans fat appears to be harder on the heart than saturated fat. The institute concluded that people should consume as little trans fat as possible.

That report has helped push the government and the food industry to start taking aggressive steps to address this long-neglected threat to public health. The Food and Drug Administration (FDA) could be close to finalizing a rule that would require trans-fat labeling on packaged foods. Canada instituted such a requirement early this year as part of its mandatory nutrition-labeling system. Labeling not only will help consumers cut back on trans, it will also be \"a profound disincentive for manufacturers\" to use partially hydrogenated oils, says Marion Nestle, Ph.D., professor and chair of New York University’s department of nutrition and food studies, and author of \"Food Politics: How the Food Industry Influences Nutrition and Health.\"

Already, Frito-Lay has said that it would eliminate trans fat from Cheetos, Doritos, and Tostitos chips. Even the fast-food industry, which generally does not have to label its foods, is starting to cut back: McDonald’s has said that in late spring of this year, its french fries would have 48 percent less trans fat--a significant improvement, though the fries will apparently still have a fair amount of trans and saturated fat.

Still, the new rule won’t mean an immediate unmasking of what Walter Willett, M.D., chair of the Harvard School of Public Health’s nutrition department, has called the \"stealth fat.\" Even if the rule is adopted soon, manufacturers won’t have to comply until January 2006.

We tested 30 top-selling foods likely to harbor trans fat. We found substantial amounts of trans and saturated fat in many products, mainly fast foods and snack foods such as doughnuts, fruit pies, crackers, and cookies, as well as shortening and vegetable-oil spread. But we also found noteworthy doses of those unhealthful fats in some less-obvious items, such as breakfast cereal and frozen waffles. Our results, combined with our advice on spotting probable trans fat in other foods, can give you a sense of where this fat lurks and how to avoid it.


DOUBLE TROUBLE

In their natural state, most vegetable oils (except tropical oils) contain mainly unsaturated fats, which lower the \"bad\" LDL cholesterol level in the blood. But partial hydrogenation changes some of those healthful fats to trans fat, which raises LDL, just as saturated fat does. Worse yet, most studies have found that trans fat lowers the \"good\" HDL cholesterol, too. So the overall effect of trans on cholesterol levels appears to exceed that of saturated fat. (Whether the trans fat in animal foods has those same effects is not yet known. And whether high-trans margarine is better or worse for the heart than butter is not yet clear.)

Large observational studies indicate that trans fat may increase the risk of heart disease considerably more than can be explained by its negative effects on cholesterol levels. To explain that gap, researchers note that trans fat clearly increases blood levels of two other suspected artery-clogging compounds: a fat-protein particle called lipoprotein(a) and triglycerides, another type of fat. In addition, trans may help inflame and stiffen the arteries. It may even increase the risk of type 2 diabetes, which ages the arteries.

Still, the average American consumes far more saturated fat than trans fat. So for individual consumers, focusing on the differences rather than the similarities between those harmful fats is \"not really that relevant,\" says Alice Lichtenstein, D.Sc., a professor of nutrition at Tufts University. Lichtenstein and other experts we consulted stress that intake of both fats should be limited, advice that’s echoed by the Institute of Medicine and the American Heart Association. Many researchers recommend restricting those combined bad fats to less than 10 percent of total daily calories, or about 22 grams on a standard 2,000-calorie diet; some researchers recommend even lower limits.

On the manufacturing level, however, focusing on trans fat could have a big effect on public health, according to Willett at Harvard. If manufacturers sharply reduced or eliminated trans fat in their foods and replaced it with beneficial unsaturated fat, there could be significant reductions in cardiovascular disease and type 2 diabetes, Willett believes.

Scientists have already created vegetable oils and additives that provide desired stability and other attributes but contain little or no trans or other harmful fats. So why aren’t more food makers moving to reduce or eliminate trans? For one thing, it’s expensive to reformulate products, and some alternative oils cost more than partially hydrogenated ones. It’s also harder to reformulate certain products than others. Changing to a low- or no-trans frying oil, for example, is generally easier than finding a low- or no-trans shortening that will yield the right texture in baked goods.

Motivation is a major factor, too. For example, margarine makers have been the most innovative in finding ways to reformulate. \"They’ve been hit hard by the trans-fat issue, so they’ve had the most incentive\" to change, notes Margo Wootan, D.Sc., director of nutrition policy for the Center for Science in the Public Interest. Once labeling becomes mandatory, more makers may be inspired to find healthier alternatives.




WHERE’S THE TRANS?

We tested mainly the top-selling foods that we knew or suspected would contain at least some partially hydrogenated oil. We found trans fat--up to 4 grams per serving--in many of those foods.

But since it’s the combined total of trans and saturated fat that matters most, the table in Bad fats in common foods lists the foods in decreasing order of total bad-fat content. There’s little benefit in choosing a food that’s low in trans fat if it’s high in saturated fat, and vice versa. Banquet Chicken Pot Pie, for example, contained just a trace of trans fat. But its 7.5 grams of saturated fat made it the top artery-clogging product on our list.

The surprising runner-up for top artery clogger: Mrs. Smith’s Apple Pie, with 4 grams of trans and 3 grams of saturated fat per slice. Other foods that you might not suspect of harboring bad fats: Nabisco Wheat Thins, Kellogg’s Cracklin’ Oat Bran Cereal, Kellogg’s Eggo Buttermilk Frozen Waffles, and Pillsbury Buttermilk Frozen Waffles.

While the amount of trans and saturated fat in many of the other tested foods may seem low, keep in mind that serving sizes are often quite small. Orville Redenbacher’s Popping Corn Movie Theater Butter, for example, contains about 1.5 grams of bad fat--but that’s in a mere 6.5-gram serving, or 1 cup, not the big bowlful that many people eat.

Virtually all the foods that had substantially less of the bad fats than similar products were low- or reduced-fat versions. Like any such foods, those lean items may not have the same texture or taste as their fattier counterparts.

Note that our table doesn’t list any fast-food french fries; McDonald’s is reformulating the one such product we tested. But manufacturers’ data provide some illuminating comparisons. Burger King’s medium fries apparently supply more trans fat and more bad fat overall than any product in our table: 4.5 grams of trans plus 5 grams of saturated fat. Wendy’s medium fries--a significantly larger serving--supply roughly the same total amount of bad fat: 6 grams of trans and 3 grams of saturated fat. McDonald’s reformulated medium fries--about the same size as Wendy’s--have less trans fat and less bad fat overall than either of those competitors. We plan to test french fries and other reformulated products in the near future to assess their bad-fat content.


RECOMMENDATIONS

Cutting back on saturated fat is still very important. That’s fairly straightforward:

Pick lean meats and eat small portions.

Choose low- or no-fat milk and cheese.

Read labels to help you choose other foods low in saturated fat. The following strategies can help you with the more difficult task of targeting trans fat in fast or processed foods:

Know \"suspect\" types of foods. Trans fat turns up in many margarines and shortenings; deep-fried fast foods and some deep-fried snack foods; many commercial baked goods such as pies, cookies, and crackers; and various other common packaged items. There are some notable exceptions, however. Potato chips, pretzels, and salad dressings generally are not made with partially hydrogenated oil. While many peanut butters contain small amounts of hydrogenated oil, they typically contain only traces of trans.

Look for shortening or partially hydrogenated oil in the ingredients list. The higher they appear on the list, and the more total fat on the label, the more trans fat the product probably contains. For example, Arnold 100% Whole Wheat Bread contains partially hydrogenated oil. But because it wasn’t high on the ingredients list and total fat was low, the trans content turned out to be negligible.

In the minority of products that list the saturated, monounsaturated, and polyunsaturated fats, you can roughly estimate the trans-fat content by toting up those fats. If the numbers don’t add up to the total fat--and if partially hydrogenated oil is a main ingredient--trans fat likely makes up most of the difference.

As a shortcut, look for products low in total fat, which means bad fats should be fairly low, too. But keep in mind that foods can be fairly high in total fat yet quite healthful--unless you’re watching your weight--if nearly all the fats are from unhydrogenated, nontropical vegetable oils.

When calculating fat content, consider the amount you’d eat, not the labeled serving size, which may be absurdly small.

Note that products can make claims such as \"low saturated fat\" and \"extra lean\" without considering trans fat, although the FDA intends to revise those definitions to limit the trans-fat content. One exception: \"saturated fat free\" means less than 0.5 gram each of saturated and trans fat per serving. Look for soft or liquid margarines, which tend to have less trans fat than harder versions.

Consider these tips from Hope Warshaw, R.D., the author of \"Eat Out, Eat Right,\" if you’re in a restaurant where nutritional information is unavailable. \"Deep-fried foods, biscuits, and pie crusts are usually made with partially hydrogenated oils,\" Warshaw says. \"In contrast, most cooks in better restaurants sauté and stir-fry in unhydrogenated oils.\" You might even try asking the waiter or cook what kind of oils are used.

EXIT63
02-15-2003, 05:24 PM
You know an awful lot about fat.....for someone who certainly is not!

Elana
02-15-2003, 07:03 PM
/ubbthreads/images/icons/smile.gif Thank you /ubbthreads/images/icons/blush.gif