THAT’S THE WAY THE COOKIE CRUMBLES (11 page)

As you see, the argument, pro and con, goes back and forth. My view is that the pros are likely to outweigh the cons, and that the biotechnology community has reasonably addressed the problems as they have arisen; it has offered effective arguments against a potential apocalypse. Still, many experience a lingering trepidation about consequences that we haven’t yet considered. Let’s face it — the intermingling of genes can lead to surprises. Parents who have crossed their genes to produce progeny can attest to that. But equating biotechnology with Chernobyl or thalidomide, as some do, is totally unreasonable. Admittedly, as we pursue biotechnology, we may cause some problems; but if we don’t pursue it, we will likely encounter bigger dilemmas. Progress always comes at a cost, but if we fear the unknown, we will never get anywhere. Nothing in life is risk-free. Certainly, in the area of genetically engineered foods we do have to move cautiously and intelligently. This means that we must not rush headlong towards developing products that we do not want or need. It also means that we should not create alarm by dressing up in masks and contamination suits to handle transgenic soybeans, as some activists have done.

Genetic modification is a hugely complex scientific, economic, political, and emotional issue. And this is certainly not my last word on the subject. Maybe I’ll even have to eat crow someday. But by then we’ll probably have a genetically modified version that is nutrient-filled and highly palatable.

Tiny Tim, the young hero of Dickens’s
A Christmas Carol
, probably suffered from rickets. In England, an epidemic of this crippling disease arrived on the heels of the Industrial Revolution, and it caused widespread misery. Children were most commonly affected. Many were forced to hobble on crutches because the weakened bones in their legs could not support them. Nobody at the time realized that this devastating affliction was linked to the newly built factories that spewed soot and smoke into the air. The skies over England were shrouded in a haze; the sun was often obscured. And that was the problem. As we learned much later, we need sunlight to produce vitamin D, a substance that is critical for proper bone formation. Furthermore, as recent research indicates, vitamin D may do more than strengthen our bones — it may also play a role in reducing the risk of some common cancers.

Vitamin D is often called “the sunshine vitamin.” This is somewhat of a misnomer, because light is just a form of electromagnetic radiation and does not transmit vitamins. What it does do, though, is trigger the formation of vitamin D from its precursor in the skin. A series of experiments that researchers conducted in the early 1900s elegantly demonstrated the phenomenon. Dogs raised exclusively indoors developed rickets, but their condition reversed when the researchers exposed them to sunlight. It was a seminal experiment with rats, however, that truly clarified the situation. In the 1920s, Hess and Weinstock at Columbia University induced rickets in the rodents by depriving them of light. Then they excised a piece of skin from each and subjected it to sunlight. When they added the skin to the rats’ food, the rodents rapidly recovered from rickets. Obviously, the light had converted some substance in the skin to an active form. Around the same time, Sir Edward Mellanby found another way of curing rickets. He, too, raised dogs in the dark until they had clearly developed weak bones. Then he tried adding various components to their diet. When he supplemented their feed with cod liver oil, the animals’ bones normalized.

It was several years before scientists managed to work out the subtleties of vitamin D. We now know that its main role is to regulate blood levels of calcium by stimulating the formation of proteins that transport calcium across the intestinal wall. But this happens in a pretty complex fashion. The active compound has the foreboding name of 1,25-dihydroxy vitamin D
₃
, and it is formed in the kidney from its precursor, 25-hydroxy vitamin D
₃
, which in turn is formed in the liver from vitamin D
₃
. The latter compound is the one we find in certain foods, such as fish oils; but, more importantly, skin that is exposed to the sun forms the compound.

Once scientists understood this, a method of reducing the risk of rickets became apparent to them. If they could somehow produce vitamin D
₃
, then people could use it as a dietary supplement — or, even better, manufacturers could add it to some widely consumed food. The method of production the scientists developed was ingenious. They exposed skin from cows, pigs, or sheep to sunlight, and they extracted the vitamin D
₃
that formed with a solvent. Milk, they decided, was the ideal vehicle for supplementation because it was a popular beverage, and it already contained calcium. Fortification of milk in North America began in the 1940s, and it soon reduced the incidence of rickets by a whopping eighty-five percent.

Over time, as childhood rickets has become more and more rare, attention has shifted to adults. More recent studies show that as much as sixty percent of the population have blood levels of vitamin D low enough to increase the risk of osteomalacia — also referred to as “adult rickets” — and osteoporosis, an even more serious condition. To a large extent, this is a result of the massive amount of publicity given to the link between sunlight and skin cancer. The elderly, especially, have taken to avoiding the sun like the plague. Too bad. Just fifteen minutes of sun exposure three times a week can dramatically increase vitamin D production and reduce the risk of fractures. Sun exposure is more effective than taking supplements; but, during winter in northern climates, the effective wavelengths of sunlight do not penetrate the atmosphere, and people must consider taking supplements. The usual recommendation is that those under fifty should have at least 200 international units (IU) of vitamin D
₃
daily (the amount in two glasses of milk); 400 IU are appropriate for people between the ages of fifty and seventy; and people over seventy need 600 IU. Some researchers think that this is not enough, because surveys show that many people who take supplements still have low blood levels of 25-hydroxy vitamin D
₃
, and they recommend a daily intake of 1,000 IU. When physicians diagnose serious vitamin D deficiency, they usually recommend a simple remedy: 50,000 IU once a week for eight weeks.

Increased blood levels of vitamin D
₃
may have other benefits. Breast, prostate, and colon cancers are more common in northern climates, possibly due to the fact that the inhabitants of these zones get less sun exposure. Some intriguing preliminary studies show that 1,25-dihydroxy vitamin D
₃
can regulate cell proliferation and reduce the risk of these cancers. All of this has prompted me to look at vitamin D with renewed interest. I was never partial to this vitamin because of the horrors it conjured up in my mind. I still shudder when I think of how I was forced to take cod liver oil as a child. I remember resisting vigorously when my mother tried to force the foul liquid down my throat. Now I know that she wasn’t trying to torture me — she was trying to keep me healthy, and she was succeeding in more ways than she knew. But I’m still not ready to swallow cod liver oil. A walk in the sunshine is a much more pleasant prospect.

I thought I had done a pretty slick job of hiding the cream-filled cookies in my shopping cart under a couple of bags of fruit. But I didn’t get away with it. “You’re not really going to eat those, are you?” a voice behind me asked incredulously. “They’re filled with hydrogenated fat! Isn’t that what you told us in class?” The gig was up. I had been caught red-handed by one of my own students. Sheepishly, I explained that I don’t make a habit of buying cream-filled cookies. But when I saw these, I had a sudden urge to recapture some happy childhood moments spent dissecting the chocolatey cookies and licking the creamy filling. Now, that was fun! Who cared that the glorious filling was nothing more than sweetened fat?

As I got older, and somewhat wiser, I did begin to suspect that something that tasted so good couldn’t possibly be good for you. And, sure enough, I learned that dipping into the cookie jar on a regular basis is not great for your cholesterol levels. Happiness comes at a price. That, one might say, is the way the cookie crumbles.

Cookie crumbling is actually a complex business. The extent to which it happens depends on several factors. Of prime importance is the development of gluten in the flour.

Gluten is a three-dimensional network of protein molecules that forms when we knead dough with water. By adding water, we cause the proteins in the flour to unravel from their natural coiled position and form cross-links to each other. This sets up the molecular scaffold that supports the other ingredients. If the scaffold is strong, with many connections, the resulting texture is tough. High-gluten flour is great for bread, because for that we need a sturdy texture, but it is not suitable for cakes or cookies.

All-purpose flour has a lower protein content and therefore less potential for gluten formation. It’s great for cookies. But the extent of gluten development is not solely a function of the protein content of the flour. The amount of fat, sugar, and water in the mix is also important. So is the mixing technique.

Fat tends to interfere with the ability of gluten to form a tough mass. It “shortens” the effect of gluten, coating the flour particles and physically separating them. Protein molecules within each particle can still form their three-dimensional gluten network, but they cannot span the gap between flour particles. This results in a texture that is ideal for pastry and cookies. But even the type of fat we select has an effect. Making a cookie crumble right requires just the right amount of saturated fat. If you want a creamy filling, you’ll also require saturated fat. And that’s the problem.

So what is saturated fat? Think of it this way. Fats are made of a framework of carbon and oxygen atoms, with hydrogen atoms attached to the carbon chains. A fat that contains as many hydrogen atoms as the carbon skeleton can support is referred to as being “saturated” with hydrogen. In the case of unsaturated fat, instead of joining to hydrogen atoms, some of the carbon atoms forge additional linkages to each other. We call these fats “unsaturated” because they contain less than their full complement of hydrogen atoms. The shape of these molecules is also different. They are decidedly kinky at the position of the missing hydrogens. The molecules are bent, and they cannot be packed together as closely as the straight saturated fats. Closely packed fats are what make for crumbly cookies and flaky pastry. They also make for clogged arteries.

When consumers got wind of this modern plague, they mounted a campaign to pressure the food-processing industry to replace saturated fats with unsaturated ones. They wanted manufacturers to banish lard, butter, palm oil, and coconut oil and replace them with unsaturated fats derived from vegetable sources. Soon, labels on processed-food packaging proclaimed that the contents were “low in saturated fats,” and hamburger emporiums announced that their french fries were now fried in “one-hundred-percent vegetable oil.” Apparently, consumer pressure had curtailed the heart-damaging onslaught of saturated fat.

But food processors had long insisted that their cookies wouldn’t crumble properly if they made them with vegetable oil, and that unsaturated vegetable fats did not meet the requirements for high-volume fast-food frying. Then, all of a sudden, these major technical difficulties appeared to be licked; suddenly, we could relax and dine on fatty cookies and french fries, our blood gushing freely through our clean arteries. Well, we shouldn’t have allowed ourselves to relax quite so fast. While the food-processing industry did, for the most part, switch from saturated to unsaturated fat, we must bear in mind that all unsaturated fats are not the same. Some actually behave like saturated fats in the body. Here’s the story. We can solidify an unsaturated vegetable oil so that it will behave more like a saturated fat — that is, we can “partially hydrogenate” it. Treatment with hydrogen gas allows some hydrogen atoms to be inserted into the molecule. Unfortunately, not only does this process make the fat more saturated, but it also converts some of the unsaturated fat molecules into a slightly different, although still unsaturated, form. These so-called trans-fatty acids have had the “molecular kink” taken out of them, and their long straight chains can now cluster together, behaving just like the infamous saturated fats we use in cookies and fried foods.

So, in a sense, we have leapt out of the frying pan and into the fire. Consumers may gain confidence by reading labels assuring them that a food contains no saturated fats, but that confidence wavers when they are confronted with the issue of trans-fatty acids. The bottom line is that trans-fatty acids, which on a product label can fall under the “unsaturated” umbrella, may be just as damaging to arteries as the notorious saturated fats. They may have taken the kink out of the molecule, but the hype about reduced saturated fats is still pretty kinky. And what happened to my desire to recapture my childhood through cookies? I tried those cream-filled concoctions. They were not as good as I remembered. So, I guess I’ll stick to fruit for snacks. No hydrogenated fats there. And I don’t have to hide fruit in my shopping cart.