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Kitchen Notes: Saturated Fats, Cholesterol, and Heart Diseas
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PostPosted: Fri Jan 06, 2006 9:51 pm    Post subject: Kitchen Notes: Saturated Fats, Cholesterol, and Heart Diseas Reply with quote


Article Digest:
So, last Wednesday I made a Coconut Creme Pie and brought it into work. No surprise, it was completely consumed with other coworkers on the waiting list for slices that were disappointed. What was surprising was a couple of the consumers commented on how bad the pie must be for their bodies. I assured them that I used no additives and kept the ingredients as fresh as possible. I admit that there were some trans fats in this particular pie because I was unable to get graham crackers without partially hydrogenated oils. It turned out that they were concerned mainly about the coconut. One of my coworkers who was watching his cholesterol levels said, "It's high in cholesterol!" I assured him that as a plant product, it was impossible for coconut to have cholesterol. Then he said, "Well, it's high in saturated fat then."

Ah, saturated fat. The most maligned and misunderstood "bad" food in the last thirty years. During the last year, I've been trying to figure out why everyone thinks saturated fat is evil and I have been unable to discover any evidence that there is evidence that saturated fats are bad for you. In fact, quite the opposite. I'll take this space and discuss briefly (although it might seem long to you) saturated fats, polyunsaturated fats, cholesterol, and the misconceptions we've been brought up with. I'll touch briefly on trans fatty acids too, but that topic is so nasty that it really deserves it's own article along with the possible manipulation of the American diet by food oil companies. Okay, back to saturated fat.

Something that doesn't help is that saturated fat is specifically called out on nutrition labels on food products as well as a Daily Value Percentage. This makes it seem that we need to limit the intake of saturated fat but not monounsaturated or polyunsaturated. This implies that saturated fats are worse than the other two fats and that is not the case.

A little background first:
Fats are composed of fatty acids which are long chains of carbon atoms with hydrogen atoms hanging off them:
     H H H H H H H H H H H
COOH-C-C-C-C-C-C-C-C-C-C-C-H
H H H H H H H H H H H
(lauric acid)
(This molecule can be written as CH<sub>3</sub>(CH<sub>2</sub>)<sub>10</sub>COOH.) If all the carbons between the carboxyl (COOH) group and the methyl (CH<sub>3</sub>) group have two hydrogen atoms attached to them then the fatty acid is considered to be saturated. A saturated fatty acid is more or less straight (in reality the carbons zigzag a bit, but the overall chain is straight). This causes the fatty acid to have a high melting point. The longer the chain, the straighter the chain, the higher the melting point. That means most saturated fats are solid. In addition, the carbon single bond is quite strong resulting in a molecularly stable fatty acid.

Unsaturated fats refer to fats containing fatty acids that do not have as many hydrogens attached as is possible. Instead of bonding to hydrogen, one or more carbon atoms form a double bond with the next carbon:
     H H H H H H H     H H H H H H H H
COOH-C-C-C-C-C-C-C-C=C-C-C-C-C-C-C-C-C-H
H H H H H H H H H H H H H H H H H
(oleic acid)
This is a monounsaturated fatty acid because it has only one carbon double bond. This particular fatty acid (oleic acid) has a double bond in the ninth position from the methyl (CH<sub>3</sub>) group making it an omega-9 fatty acid. The majority of olive oil's monounsaturated fat is composed of oleic acid. The double bond causes a bend in the chain (away from the missing hydrogens) so that the chain is no longer straight. This lowers the melting point and causes unsaturated fats (like olive oil) to be liquid at room temperature. Also every double bond in a fatty acid "weakens" the structure.
When a fatty acid has more than one carbon double bond, then it is considered polyunsaturated:
     H H H H H H H     H     H     H H
COOH-C-C-C-C-C-C-C-C=C-C-C=C-C-C=C-C-C-H
H H H H H H H H H H H H H H H H H
(alpha-linolenic)
This particular fatty acid (alpha-linolenic acid) has the first double bond in the third position from the methyl (CH<sub>3</sub>) group making it an omega-3 fatty acid. This fatty acid is found most commonly in flaxseed oil and salmon. Because of the three double bonds, this fatty acid is fragile and very sensitive to light and heat. Also, because of the three double bonds, this fatty acid curves back on itself and has a very low melting point.

When exposed to free radicals (molecules with unpaired electrons that are highly reactive), polyunsaturated fatty acids can undergo a process called lipid peroxidation which results in the polyunsaturated fatty acid to release additional free radicals. Lipid peroxidation has been directly linked to artherosclerosis (the constriction of the arteries due to build up of a plaque composed of fats, cholesterol, and other substances) and coronary heart disease (artherosclerosis of the coronary arteries that lead to the heart). Free radicals have little or no effect on the more stable monounsaturated and saturated fats.

It is commonly believed that the build up in the arteries is predominantly saturated fat and cholesterol. This is an inaccurate or incomplete statement. The plaque in the arteries varies from subject to subject, but it has been demonstrated that 3/4 of the fatty acids present in arterial plaque is unsaturated. [1] Also, cholesterol's role in the body is ignored when discussing artherosclerosis. The plaque formed in the arteries does contain substantial amounts of cholesterol, but probably because cholesterol is used as a healing agent. The damaged interior artery walls are patched up with cholesterol and then additional plaque builds up and more cholesterol is used to patch up the walls. The cholesterol is most likely not a cause of the plaque build up, but instead a body reaction to the plaque. The fact that no cholesterol is found sticking to the interior vein walls (where cholesterol concentration is the same as in the arteries) as you would expect if you were to believe the predominantly advertised theory that cholesterol causes circulatory disease. [2]

This brings us to the common belief that saturated fat increases the blood LDL cholesterol levels which in turn cause artherosclerosis. Low Density Lipoproteins (LDL) carry cholesterol from the liver to the tissues while High Density Lipoproteins (HDL) carry cholesterol in the blood back to the liver to be broken down. The buzz words "good" cholesterol and "bad" cholesterol have been used to label HDL and LDL, respectively. The belief that saturated fat lowers HDL in the blood is backed by several scientific studies, but there are also a number of studies that show that saturated fat intake can result in an increase in HDL as well. [3]Currently, there is no conclusive proof that saturated fat intake can be correlated to change in HDL/LDL ratio in the bloodstream.

An even more interesting fact is that the claim that LDL and HDL levels play an important part in heart disease and that there is a fight between "good" and "bad" cholesterol is short on supporting evidence (but long on media support). There seems to be as much scientific data that populations with high incidents of coronary heart disease tend to have higher levels of HDL (so-called good cholesterol). In addition, low levels of HDL do not correlate to an increased risk for coronary heart disease. Most interesting of all, is a study of people who have genetically caused reduced levels HDL do not have a higher risk of coronary heart disease. [4] Studies across several countries with similar HDL-LDL levels resulted in very different incident rates of heart disease. If the theory that HDL-LDL leads to heart disease is to be true, then a more consistent death rate from the disease would have been evident in these countries. It has also been shown that cholesterol level in the blood stream has no correlation with heart disease. In fact, over 80% of people who suffer heart attacks, do not have elevated cholesterol levels. [5] In addition, only 30-40% of people with artherosclerosis have elevated cholesterol levels. [6] It seems that cholesterol is neither a good indicator nor a risk factor for heart disease. (Note: A very small percentage of people have a genetic illness called hypercholesterolemia which interferes with their ability to matabolize cholesterol. People with this genetic condition do have to watch blood cholesterol levels.) [7]

So, what is the next most likely candidate for leading to heart disease? Lipoprotein (a) or Lp(a) has been pointed to as a coronary heart disease risk factor. [8] Although research is incomplete, early findings have been strongly suggesting that Lp(a) contributes to and promotes atherosclerosis. Evidence currently points to trans fatty acids as a major increaser of Lp(a) levels. What's ironic is that saturated fats have been linked to lowering Lp(a) levels! [9]

So, what are trans fatty acids? In unsaturated fatty acids, the carbon double bonds cause bends because the two bonded hydrogens are next to each other (cis). If the hydrogens alternate, then the carbon chain is once again straight. This is referred to as trans.
     H H H H H H H   H H   H H   H H H
COOH-C-C-C-C-C-C-C-C=C-C-C=C-C-C=C-C-C-H
H H H H H H H H H H H H H H
(trans-9,trans-12,trans-15-octadecatrienoic acid)
Trans fatty acids are created through partial hydrogenation of fats (natural or chemical). In nature this occurs rarely and results in very small amounts of trans fatty acids. In our supermarkets, this is a common place fatty acid. It was discovered that if you partially hydrogenated a fatty acid, about half of the fats would have bends going the other way (not in the same direction: cis), thus straightening out the chain. This causes the fatty acid to have a higher melting point, allowing the public to enjoy solid fats without the saturated fat (which was thought to be bad at the time). Margarine replaced butter, shortening replaced palm oil and lard, and partially hydrogenated soybean oil replaced coconut oil. During the last ten years, a great deal of research has been performed on trans fatty acids and the conclusions are not good. Trans fats (fats made of trans fatty acids) promote artherosclerosis and other cardiovascular dieases and increase the risk factor for cancer. In addition, trans fats have been found to replace necessary saturated fats in fat cells resulting in an unusable substance taking the place where a fuel and nutrient source should have been. This leads to the body increasing capacity of fat cells in order to maintain fuel and nutrient storage levels. Trans fats are also unstable and may lead to promotion of free radicals in the human body (for the same reasons that polyunsaturated fats do). It should be noted that fully hydrogenated fats are the same as saturated fats and do not exist in cis or trans formations (as there is no bend).

So, now we have discussed how saturated fats do not cause directly or indirectly heart disease, cholesterol is not an indicator or risk factor of heart disease, polyunsaturated fats should be reduced in the diet, and trans fats are to be avoided completely. (Pretty much the opposite of what the media and food oil producing companies tell us.) But, I haven't discussed any benefits of saturated fats.

Before I get into that, I want to mention that although a reduced polyunsaturated fat intake is recommended, there are two families of essential fatty acids that we should intake: omega-3 and omega-6. These are polyunsaturated fatty acids where the double bond is three or six carbons from the methyl group. About 1-2% of the calories you intake in a day should be omega-3 and about 2-3% should be omega-6. Too much omega-6, however, can limit your body's ability to use omega-3 fatty acids. Omega-3 fatty acids can be found in fish, flaxseed, walnut, and unprocessed soybean oil (the processing that removes color and oil from soybean oil pretty much destroys all the linolenic acid in it).

In a past article, I've mentioned that I cook predominantly with olive oils and butter. Here's why: olive oil is high in monounsaturated fat. In fact it is less than 10% polyunsaturated. Butter is less than 4% polyunsaturated and contains a large amount of heathful substances. These include naturally occuring vitamins (A, D, E, and K), small amounts of linoleic (omega-6) and linolenic (omega-3) acids, butyric acid (demonstrated anti-tumerigenic properties and a major fuel source for intestines), lauric acid (anti-microbial and anti-viral), glycosphingolipids (protects against intestinal infections), conjugated linoleic acid (strong anti-cancer properties and helps prevent weight gain; found only in butter and milk from grass-fed cows), lecithin (assists in metabolising cholesterol and fat components), selenium (aids vitamin E as an antioxidant; butter is one of the richest selenium food sources available), and cholesterol. It might seem weird to list cholesterol as a benefit, but cholesterol is a precursor to vitamin D and many hormones as well as an antioxidant and the body's primary repair substance. Consuming cholesterol also contributes to intestinal wall health. Ingesting cholesterol on a regular basis has been shown to not increase blood cholesterol levels because the body reduces its natural production and increases cholesterol metabolism to compensate.

It should also be noted that the small amount of ingested cholesterol can hardly be noticed in the large amounts of cholesterol flowing in your blood stream. For example, if you are capable of intake half of the cholesterol you consume daily (let's say 150 milligrams of 300 milligrams consumed) and you compare that to the amount of cholesterol in the blood (150 mg/dL), then you'll find that of the 7500 mg of cholesterol in your blood (150 mg/dL * 10 dL/L * 5 L/human) you've added only another 150 milligrams (assuming your body is even capable of intaking 50% of the cholesterol you've ingested). A healthy body can easily throttle back cholesterol production and increase metabolism to absorb the additional cholesterol intake.[3]

1. Felton CV, et al; Dietary Polyunsaturated Fatty Acids and Composition of Human Aortic Plaques. Lancet, 1994.

2. Cranton EM and Frackelton J; Free Radical Pathology in Age-Associated Diseases. Journal of Holistic Medicine, 1984.

3. Enig M; Know Your Fats: The Complete Primer for Understanding the Nutrition of Fats, Oils and Cholesterol; Bethesda Press, 2000.

4. Smith R and Pinckney E; Diet, Blood Cholesterol, and Coronary Heart
Disease: A Critical Review of the Literature. Vector Enterprises, 1991.

5. Rowland D; The Nutritional Bypass. Heath Naturally Publications, 1995.

6. Reiser R; The Three Weak Links in the Diet-Heart Disease Connection. Nutrition Today, 1979.

7. Byrnes S; Diet and Heart Disease: It Is Not What You Think. Whitman Publications, 2001.

8. Garrison J and Somer E; The Nutrition Desk Reference; Keats Publishing, 1995.

9. Enig M; Fat Facts; Price-Pottenger Nutrition Foundation Journal, Winter 1998.

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PostPosted: Fri Jan 06, 2006 10:15 pm    Post subject: Reply with quote

Interesting - may I ask, if cholesterol in the blood in not a "risk factor of heart disease," why is anti-cholesterol medicine commonly prescribed to those with a risk of heart disease?
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PostPosted: Fri Jan 06, 2006 10:16 pm    Post subject: Reply with quote

It's to make drug companies money.
I used to be required to take lipitor, but since i lost my job 8 mos. ago
due to the failing economy, (due to the bad decisions of an inbred, retarded texan), I had to get on indigent health care.For some strange reason they say I don't need it anymore? I've only been taking it for one month.
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Michael Chu



Joined: 10 May 2005
Posts: 1626
Location: Austin, TX (USA)

PostPosted: Fri Jan 06, 2006 10:16 pm    Post subject: Reply with quote

I like to think it's the same reason why most professional chefs still put oil in the water that they boil pasta in. Habit, tradition, makes them feel better because that's what their mother (doctor) told them.
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PostPosted: Fri Jan 06, 2006 10:17 pm    Post subject: Reply with quote

I was told putting a little bit of oil in the water keeps the pasta apart...ie not stick together.
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PostPosted: Fri Jan 06, 2006 10:17 pm    Post subject: Reply with quote

A Tablespoon of butter will help a pot of boiling pasta not boil over.
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PostPosted: Fri Jan 06, 2006 10:17 pm    Post subject: Reply with quote

Yes, oiling your pasta keeps the noodles from sticking to each other, but it also makes it harder for sauces to cling to the noodles. I find if I stir the pasta immediately after adding it to the boiling water, and once or twice while cooking, they don't stick together.
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PostPosted: Fri Jan 06, 2006 10:18 pm    Post subject: Reply with quote

regarding taking lipitor/anticholesterol meds:

People make practically all the cholesterol in their bodies. Some people make too much, such as type2 diabetics. The lipitor helps these people to drive those levels down. It may come as surprising to some, but the liver generates cholesterol in response to sugar, and not to fat.
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PostPosted: Fri Jan 06, 2006 10:19 pm    Post subject: Reply with quote

Michael, I think you are in danger of repeating the mistakes of the past (which you recognise) by being two quick to implicate trans fat and too quick to (completely) exhonorate saturated fat.

As you no doubt know, most dietary studies are short-term observational studies that, even when not flawed in methodology, are statistically very weak.

As University of Maryland researches pointed out (in a cautionary note to their 1997 study where the data suggsted that total fat, monosaturated fat, and monounsaturated fat all reduced stroke risk -- the first study to indicate this in caucasians): "Large-scale experimental studies that would provide more compelling data (such as the Women's Health Initiative) cost hundreds of millions of dollars and take decades to complete. Each study can only address the effects of a single nutritional change. Thus, it is still necessary to base advice to patients on dietary information that is less than certain and incomplete."

To the extent that the lipid model many be true, it is true in very complicated ways. The only answer we have is to do statistical analysis on the study results themselves and see what the proponderance of them say. Dietary advice should change very slowly. It is amazing to me how we have can go from one extreme to another. Pritican and Atkens are two examples of (contradictory) extremes; the only thing being more extreme than their advice is the extremism of their proponents!

In many of the recent studies, olive oil was used as a "control" group against trans fat. Olive oil is a poor control because it is known to be healthy. The high trans fat group was forced by definition a low monounsaturated group, although this was unrealistic due to trans fat being a small portion of total fat calories consumed. However, the results of these studies are primarilly being applied to the "Butter vs. Margarine" question. In this case, the trade off in the study should have been trans vs. saturated, but (as you have pointed out) there is such a bias agaist saturated fat that this was not done.

The FDAs recent advisories against trans fat are all based on a number of studies, but nearly every one of them is authored or co-authored by one researcher: Harvard University’s Walter Willett, a member of the radical Center for Science in the Public Interest (which was the group that petitioed the FSA for a trans fat labeling requirement). The CSPI is known for using scare tactics and singling out individual foods as "dangerous" (something no respectable dietician does).

The majority of studies that Willet is not involved in fail to find such a link. Also, the studies that did find "issue" with trans fat linked them to LDL, not disease risk. Not a one found increased corinary artery disease. You pointed out above that you are suspicious of blood lipids as isolated risk factors, but you seem willing to indite trans fat using the same indicators.

Specific studies:

The "Boston" study or 239 patients that linked trans fat with LDL/HDL ratio dis not correct for smoking, excercise, medical history, and familly medical history,

The Bolton-Smith study found no statistically significant result.

The most conclusive of Willett's studies found a link only with the highest trans fat consumption group and the relative risk index of 1.53 was well short of what one would accepet as statistically sound (ie 2.0 or more)

I'd like to see some independant confirmation (ie. not just Willett and Ascherio) of these numbers and a link to disease (not just serum lipid levels) before making any conclution differentiating between trans fat and other polyunsaturates.
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Michael Chu



Joined: 10 May 2005
Posts: 1626
Location: Austin, TX (USA)

PostPosted: Fri Jan 06, 2006 10:19 pm    Post subject: Reply with quote

re: Pasta and oil

What causes the pasta to not stick together is a large quantity of water to cook in (at least 4 quarts). This allows the starches to disperse into the water so the pasta does not clump in the pot. Oil simply floats at the top of the water (which may or may not keep the water from boiling over - I'll have to look into that).

It's best to apply a bit of oil (or the sauce) directly to the pasta after draining (with perhaps a bit of reserved water). This will insure the pasta doesn't stick and the sauce will still stick.
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PostPosted: Fri Jan 06, 2006 10:20 pm    Post subject: Reply with quote

Wow! It's my first time to visit your blog and I love it, Michael!
I once posted in my blog about coconut oil ( http://manangkusinera.blogspot.com/2004/06/coconut-milk-and-coconut-oil-is-it.html#comments ), with some similar issues tackled in your post re the marketing strategies of food oil companies and the uses of fats and oil in our body, also another post about cholesterol and triglycerides in http://manangkusinera.blogspot.com/2004/07/cholesterol-and-triglycerides.html#comments.
I do not get swayed easily by so-called recent studies, because before I believe that something that has been traditionally used is bad, I like arriving at empirically derived conclusions subjected to logical assessment.
Recently there was an update on the guideline in cholesterol management, which has lower values to be considered normal. The studies "supporting" the guideline were sponsored by the pharmaceutical industries, with the end-result of prescribing anti-cholesterol agents to more patients (with the addition of previously normal-cholesterol-level patients).
Yeah, fat is too maligned and misunderstood. I am glad to have found another ally in this fight against anti-fat fads (the same is true with anti-carb fads). Why don't the people just use their common sense? Oh, I almost forgot, common sense is not so common nowadays.
I commend you for sharing your valuable knowledge. I added your blog as a link to mine. Thanks for sharing.
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PostPosted: Fri Jan 06, 2006 10:20 pm    Post subject: Reply with quote

How wonderful to see someone commenting on he cholesterol myth in such a popular forum (love the recipes and the format). The drug company inspired crusade against cholesterol and the subsequent ignoring of other aetiologies for heart attacks ignores the obvious: mammals have eveolved in an environment where saturated animal fat was in plentiful supply, whereas transfats and polyunsaturated fats/oils were not.
Cholesterol and lipoprotein A are checmicals formed as the result of inflammation in the body. While lipoprotein A blood levels have a near 1:1 correlation with heart attack risk and can be used as an absolute indicator of heart attack risk, cholesterol has a far far lower correlation. Lipoprotein is not affected by fat intake, which strongly implies that the cholesterol model is wrong.
The cholesterol model also ignores findings that around 70% of people with recent heart attacks have antibodies against a chlamydia, and that anti-chlamydial antibiotics have a dramatic effect in reducing post-CVA relapse/recurrance. It also ignores other epidemiological studies that heart attacks run in groups that would suggest an infectious agent.
Bt we live in a world where medical research is funded by large corporations who are interested in funding and disseminating research findings that will support increased sale of their products. Antibiotics are past their patent periods, so are too competitively priced to make money for the companies.
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PostPosted: Fri Jan 06, 2006 10:21 pm    Post subject: Reply with quote

I used to add oil to pasta water until being voiciferously told it's a major no-no (the sauce won't coat / penetrate the pasta properly).

4 quarts and half a handful of kosher salt is appropriate for one pound of pasta (it takes awhile to boil, so plan accordingly). Use a big pot and cook uncovered, and it won't boil over or stick (just stir very well when you add the pasta to the already boiling water). The salt improves the cooking and also raises the boiling point of the water a bit, while somewhat taming boilovers.

When al dente (with practice, can tell this just by stirring the pasta; otherwise, sample a piece), drain in colander (don't rinse) and then put in bowl, add sauce, stir to coat.
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PostPosted: Fri Jan 06, 2006 10:21 pm    Post subject: Reply with quote

I found the comment, "In fact, over 80% of people who suffer heart attacks, do not have elevated cholesterol levels.[5]" very interesting. I may be true, based upon the originating research. I would be hesitant to quote David Rowland after reading this article on Quack Watch.

http://www.quackwatch.org/11Ind/rowland.html
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PostPosted: Fri Jan 06, 2006 10:21 pm    Post subject: Reply with quote

>if you are capable of intake half of the cholesterol you consume daily (let's say 150 milligrams of 300 milligrams consumed) and you compare that to the amount of cholesterol in the blood (150 mg/dL), then you'll find that of the 7500 mg of cholesterol in your blood (150 mg/dL * 10 dL/L * 5 L/human) you've added only another 150 milligrams (assuming your body is even capable of intaking 50% of the cholesterol you've ingested). <

So, hmm, they always make fun of the old practice of bloodletting. But it's kind of one way to cut cholesterol... (leaving aside for the moment the issue of whether it's bad to have x amount of cholesterol in your blood) Smile
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