01/30/2003
Good Fat, Bad Fat
As a self-appointed music critic, I feel it’s my duty to help you avoid a painful experience. OK, I admit that I have no musical credentials but if, like me, you enjoy works by Tchaikowsky, Beethoven or any of the Strausses, do not attend a performance of works by Anton Webern. Last week, I looked forward to the appearance of Zubin Mehta and the violinist Midori with the New York Philharmonic Orchestra. Mehta chose, for the whole first half of the program, to examine the life of Webern. The first number, composed by Webern at age 20, was harmless enough. Unfortunately, Webern later came under the influence of a guy named Schoenberg, one of those avant-garde types.
Webern’s Six Orchestral Pieces were termed “slow, moving, moderate, very moderate, very slow and slow” while his Concerto for Nine Instruments contained “somewhat lively, ver slow and very spirited” movements. To me they all sounded like something a two-year old could produce with random pounding of the keys. The Concerto was something else, subverting the talents of nine highly accomplished musicians. The playing rotated within the group with, except for the piano, each instrument playing no more than two or three notes before handing off to the next instrument with a different tempo. Not a hint of a melody or unifying theme. Our bus group unanimously declared Webern a disaster.
It was enough to drive a man to drink, the subject of last week’s column. As a follow-up on that column, you may recall that I quoted cardiologist Arthur Klatsky as saying that there is solid evidence supporting the finding that alcohol increases HDL. However, he said there is only moderately supporting evidence for a decrease in fibrinogen, a protein that promotes clotting in the blood. This week I came across an article suggesting this anti-clotting benefit is on more solid ground. In the January 20 issue of Chemical and Engineering News, K. M. Reese cited a study published last month in Nature by Shela Gorinstein and her colleagues in Israel.
The Israeli workers took 48 men with coronary artery problems, split them into two groups and, for the next 30 days, one group drank mineral water while the other group drank one beer a day. The diets otherwise were quite similar in the two groups. At the end of 30 days, 21 of the 24 alcohol imbibers had beneficial changes in their blood chemistry from the standpoint of heart health. Their blood had lower cholesterol, more antioxidants and less fibrinogen. In addition, the structure of the fibrinogen was altered in a manner making it less effective in clotting. For Brian Trumbore’s benefit, their drink was “standard pale lager”, but the scientists expect other beers would have the same benefits. As in the previous column, I stress the message that moderate alcohol consumption, no more than 1-2 drinks per day, is the key to these heart health benefits.
Having dispensed with the beverage issue, let’s consider the other burning dietary issue of the day – fat. I’m indebted to an article by Wilder D. Smith in the November 2002 issue of Today’s Chemist at Work for stimulating this column. The article was a short, succinct article summarizing the chemical nature of fats. However, I was concerned about one seemingly incorrect statement in his article and I scoured the Web to confirm my concern. I was especially enlightened by material on Nutrition Australia, the Web site of the Australian Nutritional Foundation.
Unless you’ve been in hibernation for the last few decades, you’ve been bombarded with information on saturated, monounsaturated, polyunsaturated and trans fats. What is a fat? A fat is a compound that combines three fatty acids and glycerin into a single molecule. When we talk about saturation, we should be talking about the fatty acids that make up a particular fat. In natural fats, the fatty acids in a given fat are not all of one degree of saturation. When it comes to oils, for example olive oil, we have to consider the different fatty acids to decide as to whether to call it monounsaturated, polyunsaturated or saturated. We’ll see shortly that it’s a mixture of all three.
What are saturation or unsaturation and what are fatty acids? Fatty acids are compounds consisting of long chains of carbon atoms ending with a group consisting of carbon, oxygen and hydrogen, written as COOH. We’ve discussed on occasion the fact that carbon has four electrons that want to pair up with four electrons from other atoms. Each shared pair of electrons is a chemical bond; hence carbon forms 4 bonds. Hydrogen has only one electron and can share it with a carbon electron, resulting in a C-H bond. In a fatty acid the first carbon in the chain will have 3 hydrogens bonded to it, CH3, known as a methyl group. In a saturated fatty acid, the rest of the carbons will each typically have two hydrogens bonded to them and have two bonds to the adjacent carbon atoms in the chain. The chemical formula looks like CH3CH2CH2CH2…….CH2COOH, where the …… indicates more CH2 groups. In stearic acid there are 16 of these CH2 groups. These saturated fatty acids have all the hydrogens the carbon atoms can accommodate.
Suppose two hydrogens are missing. Now the formula is CH3CH2CH=CHCH2……CH2COOH. The = sign signifies what we chemists call a double bond – the two carbon atoms have fewer hydrogens to share with and consequently have to share two pairs of electrons with each other. This fatty acid, with one double bond, is called a monounsaturated fatty acid. If even more hydrogen is missing and we have two or more double bonds, we call the fatty acid polyunsaturated. Saturated fatty acids tend to be solid at room temperature while polyunsaturated fatty acids tend to be liquid.
Let’s consider now some of our fatty foods. It’s instructive to look at the PMS ratios (not what you think, ladies), the percentage ratios of Polyunsaturated:Monounsaturated:Saturated fatty acids in the foods. Take olive oil, commonly called a monounsaturated oil. Its PMS ratio is 10:76:14. Some other PMS ratios are: Canola oil (30:63:7); Butter (7:36:57). Olive oil is highly recommended for health diets and you can see why, with 76 percent monounsaturated fatty acids. Butter, on the other hand has 57 percent saturated fatty acids. Better to dip your bread in olive oil than spread it with butter.
Margarine, which in Australia has a P:M:S of 33:33:34, was long thought to be better than butter for your health but you no doubt have heard the relatively recent findings about trans fats (fatty acids) in the margarine. Where do trans fats come into the picture? Trans fats are introduced when some of the ingredients in margarine are hydrogenated. This addition of hydrogen helps make the margarine the right consistency and also helps preserve it longer.
What are “trans” fatty acids? How do they differ from natural so-called “cis” fatty acids? Let’s look at the two structures around the double bond:
```````H````H````````````````````H````````````````````````````````` `````````````/``````````````````````````````````````````````````````` ````````-C=C-``cis```````````````-C=C-``trans``````````````````` ``````````````````````````````````````````````````````````````````````` ````````````````````````````````````````````H``````````````````````````
(Ignore the ```s. Pretend they’re not there. The #$%^* !+& software transferring my text onto the site won’t recognize my blank spaces. I had to resort to ```s to line up the hydrogens.) Simplistically, in a cis fatty acid, hydrogens are on the same side (above or below) of the double bond. In trans fatty acids, the hydrogens are on opposite sides (above and below) of the double bond. The chemical formulas are the same but the relative positions of the hydrogens are different. Offhand, you might not think this slight difference would have much effect on the properties. However, judging from the reported bad effects of trans fats in our bodies, it’s clear that there’s a big difference in the chemistry. The trans fatty acids have come to be known as villains in our diets and their presence in all sorts of products is now a matter of considerable concern in the field of nutrition.
As for musical nutrition, Mehta and Midori compensated for the Webern with a fine second half performance of Elgar’s Violin Concerto. And that evening, Leslie Uggams and the cast of “Blue” were superb at the Paper Mill Playhouse. Lest I forget, our cultural diet that day was also enriched by our morning at the Metropolitan Museum of Art’s exhibit of original sketches by Leonardo Da Vinci. It was a full day!
Allen F. Bortrum
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