March 20, 2012

14 Min Read
Feeling Better About Fat

By Kimberly J. Decker, Contributing Editor

Its hard to recall a time when fat wasnt in someones crosshairs. Whether it was contributing to obesity, increasing the risk for heart disease or adding to an already-overflowing caloric balance, fat always seems to be taking the heat from one nutrition policy or another.

But fat hasnt worn its scarlet F" for as long as we might think. In fact, it was only in the 1980s that the USDA Dietary Guidelines for Americans began advocating lower-fat diets in the first placeand, in so doing, setting the conditions for the anti-fat miasma that persists today.

That miasma is almost certain to dispel, though, as we learn more about the relationship between fat and health. The latest science proves that some fats, far from deserving elimination, actually merit greater representation in our diets, and thats prompting policy-makers to craft messages more nuanced than Just say low." As product developers, we should see that as our cue to reexamine whereand whichfats fit into our formulations. The endeavor could prove enlightening.

Giving fat a fair shake

Emerging science aside, the public still has a dim view of fat. According to the 2011 International Food Information Council Foundation (IFIC) Food & Health Survey, fully 71% of consumers are trying to limit dietary fat, principally the trans fats and saturates theyve been warned so much about. But the extent to which consumers see any fat as good" remains slim; the same survey found that nearly one in five consumers believes theres no such thing as a healthy fat.

Thats not giving fat a fair shake. As Willie Loh, Ph.D., vice president, marketing, Cargill Oils and Shortenings, Wayzata, MN, says: Fat is critical to life. Fat provides structure to most of what is living tissue. In every single cell, the nuclear membranes, the mitochondrial membranestheyre all made from fat."

Fat also supplies concentrated energy, sparing protein from use as fuel and reducing muscle breakdown. Stored fat acts as an insulator to protect the body from changes in heat and cold, and to protect the internal organs from damage caused by impact with other organs in the body," adds Janet Collins, Ph.D., R.D., senior manager, corporate regulatory affairs, and manager, Ag and nutrition biotech advocacy, DuPont Nutrition & Health, Washington, D.C.

Without fat, wed lose our principle source of the fat-soluble vitamins A, D, E and K, as well as the essential fatty acids (EFAs) linoleic acid (LA) and alpha-linolenic acid (ALA). These polyunsaturated omega-6 and omega-3 fatty acids participate in everything from hormone development and skin and hair health to the inflammatory responsebut our bodies cant synthesize them sufficiently on their own. Thus, we harvest EFAs from fats in the diet, like soybean, corn and safflower oils, walnuts and flaxseed.

Market saturation

Ironically, Loh observes, our bodies can synthesize all the saturated fatty acids we need,"the irony being that while EFAs can go wanting in our diets, we eat more than enough of the meats, dairy, and eggs that supply us with saturates we dont need.

The latest Dietary Guidelines acknowledge this imbalance by backing away from previous calls for blanket fat reduction. As Collins says, More recent guidance from the 2010 U.S. Dietary Guidelines for Americans separates types of fats, with recommendations to consume less than 10% of calories as saturated fats, and to increase monounsaturated and polyunsaturated fatty acids in a diet that is to get 20% to 35% of total calories from fat."

Yet even these more nuanced guidelines may prove struggling for Americans to follow. As Loh points out, were significantly over" that 10%-or-less saturated-fat ceiling, which is why saturate reduction is currently the focus of a number of initiatives."

The health perils of a diet high in saturates are well documented. A strong and positive correlation was found in population-based, epidemiologic studies between levels of consumption and cardiovascular disease," Collins says. In other words, populations that consume higher levels of saturated fatty acidsand cholesterolwere found also to have higher rates of cardiovascular disease," she says. And though the relationship is not seen to be cause-and-effect," it is a strong indicator that cardiovascular disease would be a problem in these populations."

Yet even the seemingly established connection between saturated fat and heart disease isnt entirely settled. Natural dietary fats are combinations of different fatty acids," notes Gerald P. McNeill, Ph.D., vice president of R&D, Loders Croklaan NA, Channahon, IL. "Palmitic acid is the most common saturated fat in our dietsand in living things in generalat about 65% of total saturates; stearic acid is the next most abundant; and several others follow." In the 1980s, he says, scientists noticed that palmitic acid increased both total cholesterol and bad" low-density lipoprotein (LDL) cholesterol more than did stearic acid, another commonly consumed saturated fat. Thus, he says, A theory was proposed that stearic acid was neutral and that palmitic acid raised risk of heart disease." But this theory failed to account for effects on good" high-density lipoprotein (HDL) cholesterol, and when more recent studies looked specifically at HDL, they found that palmitic, and not stearic, raises its levelsa desirable outcome.

Further complicating things, McNeill continues, When the LDL:HDL ratio is calculated, it shows that there is no significant difference between the fatty acids, and that both appear to be neutral." He adds that the Nurses Health Study attempted to separate palmitic from stearic effects on heart disease, but could find no difference, either. The conclusion," he says, is that saturated fats are neutral."

Then why the USDA guidelines to eat less of them? Ultimately, the 2010 recommendations jibe with guidance from other bodies, including the Food and Agriculture Organization of the United Nations, the Institute of Medicine and the American Heart Association, in calling for saturate reduction. As Loh says, If we can simply reduce the overall level of saturated fat, were going to have a healthier population." For now, at least, he may be right.

Transformative advice

The risks of trans fat appear to elicit far more consensus, and even McNeill concedes, There is no reason to keep trans fat in the diet." The 2010 Dietary Guidelines reflect this, recommending that consumers eat as little trans fat as possible within the context of a nutritionally adequate diet. While they stop short of setting maximum levels, the guidelines do note that increased risk exists at any level above zero.

We used to think that trans fats were a good substitute for saturated fat, especially since trans fats are unsaturated fatty acids," says Penny Kris-Etherton, Ph.D., R.D., F.A.H.A., distinguished professor of nutrition, College of Health and Human Development, Pennsylvania State University, University Park, PA. Little did we know at the time that they would have many adverse health effects."

Those effects appear to stem from the unique kink" in trans fats double-bond structure. As a result, David Dzisiak, commercial leader, grains and oils, Dow AgroSciences, Indianapolis, says, Trans fats raise your bad LDL cholesterol levels and lower your good HDL cholesterol levels. Eating trans fats increases your risk of developing heart disease and stroke. Its also associated with a higher risk of developing type 2 diabetes."

But even before the latest Dietary Guidelines, artificial trans fats were becoming harder to find in packaged foodsor in us. Recently, reports from the U.S. government have demonstrated a 50%-plus reduction in blood levels of trans fatty acids in the U.S. population in the past 10 years," Collins says.

According to her colleague, Susan Knowlton, Ph.D., senior research manager, Pioneer, a DuPont business, Wilmington, DE, Several new oils have been developed to help the food industry cut trans fat from their products while providing functionally stable oils for food preparations, including high-oleic oils."

Collins praises the effort. The food industry has made great strides to remove hydrogenated fatsand, thus, trans fatty acidsfrom their products," she says. And with the FDA implementation of a trans labeling requirement, these factors are better known to consumers."

Listening in mono

So if we scrub our diets of trans and saturates, whats to take their place? When you consider that 25% to 35% of an adults total calories should come from fats," Dzisiak says, and less than 10% of that should come from saturated fats, that means at least 15% to 25% of total calories should come from healthy polyunsaturated and monounsaturated fats such as omega-3s, omega-6s and omega-9s."

 Dzisiak points to research revealing a positive health role for monounsaturated omega-9 fatty acids. Because omega-9 fatty acids have been shown to increase HDL good cholesterol and decrease LDL bad cholesterol, they help eliminate the plaque buildup in the arteries that may cause heart attack or stroke," he says. Foods high in omega-9 monounsaturates include vegetable oils such as olive, canola, peanut, sunflower and sesame. Other sources," Dzisiak says, include avocados, peanut butter and many nuts and seeds."

Most consumers associate omega-9s with olive oil, thanks to the publicity given the Mediterranean diet. Much attention has been drawn to the Mediterranean dietary pattern," Collins agrees, which contains a high level of the monounsaturated fatty acid oleic acid." Food processors eager to incorporate those Mediterranean monounsaturates into products that may not accommodate olive oil can choose alternative oils with good quantities of oleic acid" in process-friendly form.

Knowlton says her companys high-oleic soybean oil has 20% less saturated fat than commodity soybean oil, 75% fewer saturates than tropical palm oil and more than 75% oleic contentall in a zero-trans substitute for hydrogenated oils. And the high-oleic trait combines with naturally occurring tocopherols to make the oil more stable than other crop oils with similar fatty acid compositions," she says.

Good things come in 3s

But not everyone is bullish on monounsaturates benefits. There is no conclusive evidence," McNeill declares, that monounsaturated fat is better than saturated fat." In fact, he says, it may provide no benefit at all."

Loh agrees, saying that monounsaturated fat may be, at best, neutral."

But they and others are enthusiastic about the health potential of polyunsaturated fats found in some vegetable oils, fatty fish and some nuts and seeds. Polyunsaturates clearly have demonstrable medical benefits, especially when they replace saturated fat," Loh says. And among the polyunsaturates, which are the omega-6s and omega-3s, the omega-3s are the ones that have clearest benefits."

Even the general public is hip to their benefits, with fully 50% identifying omega-3s" as healthful in the IFIC survey. Epidemiologic studies have provided correlative data to support reductions in heart disease in populations consuming high quantities of fish," Collins says. In the past 10 years studies are looking at specific omega-3 fatty acids"principally long-chain docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), as well as short-chain ALAto evaluate their individual health impacts."

As the science now stands, long-chain DHA and EPA apparently boost heart health more than short-chain ALA. But besides the heart-health benefits, Loh says, When you go to the long chains, you get a lot more. You have other benefits like brain development, cognition, visual acuity, blood pressure and so forth." And while its true that the body can convert ALA to its long-chain cousins, it does so via an inefficient and somewhat overtaxed enzyme system that generally renders conversion suboptimal in modern diets.

One reason for this inefficiency is that the same elongase and desaturase enzymes that turn short-chain ALA into long-chain omega-3s also convert the short-chain omega-6 LA into its long-chain metabolites. Because we consume so many more omega-6s than omega-3 fatty acids, the former crowd the latter from the conversion machinery," as it were, and our cells can lack for adequate DHA and EPA as a result.

Furthermore, Collins says, Some researchers have seen the increasing omega-6 fatty-acid content of the U.S. diet over the past 50 years as associated with many of the increased rates of inflammatory diseases in the population. Diseases like obesity, diabetes, insulin resistance and others have steadily increased in the U.S. population over these same years. It is unclear what the relationship is among the fatty acids and various health and disease states. This is a controversial area of study globally."

In any event, a sound path would be to rebalance the diet more toward the omega-3s we know we need, and away from the omega-6s that we get enough of already. Although no Recommended Dietary Intake level for omega-3s yet exists, authorities have settled on between 1,000 and 3,000 IU of combined EPA plus DHA as being effective, Collins says.

As for nutrient content claims, FDA has determinedbased on the IOMs adequate-intake dose of 160 mg of EPA and DHA per daythat foods containing 32 mg of EPA and DHA per serving can claim an excellent source" distinction for the omega-3s. Because the short-chains are not as efficacious as the long-chains," Loh notes, to qualify for the FDA claims, you have to put in 10 times as much of the short-chain as the long-chain." That works out to 320 mg per serving. The different amounts reflect reality," he says. They reflect the best science that we have."

In for the long haul

The challenge to delivering omega-3sshort-chain or longis mainly one of maintaining their stability over a products shelf life. Omega-3s, being polyunsaturated, are liable to oxidation with increasing unsaturation. In the case of alpha-linolenic acid," Loh says, youve got three double bonds; in the case of EPA and DHA, youve got five and six." When oxygen attacks those double bonds, youll get some very green notes and some paint notes because the oxidation products of these oils have extremely acute off odors," he says.

Antioxidant systems that oil suppliers build into their high-omega-3 products protect the oils for use in foods with longer shelf lives. Weve been successful in stabilizing a form of ALA in flax oil that lets us deliver 320 mg of an omega-3 that, while short-chain, can give 12 months shelf life in a slice of bread or a cookie or a cracker," Loh says. Previously, if you tried to do that with fish oil or pure flaxseed, it would start to turn on you in about two-and-a-half months."

This solves what Loh calls the periphery problem." When you look at the preponderance of omega-3 products," he says, what you find is that most of them are in the periphery of the supermarketthe refrigerated case. Youll see them in margarines, yogurts, single-serve drinks that are sealed and kept cool. And thats fine, but what our customers have asked is to see them in cookies and crackers and barsthings that require shelf life."

So the unmet need isnt finding a healthy oil source; the nutritional part is easy to solve," Loh says. Its the functionality issues that have to be addressed." As oil processors continue addressing them, theyre bringing functionaland healthfulfats to more products, and to more peoples diets.

Kimberly J. Decker, a California-based technical writer, has a B.S. in consumer food science with a minor in English from the University of California, Davis. She lives in the San Francisco Bay Area, where she enjoys eating and writing about food. You can reach her at [email protected].

Communicating Fats on the Nutrition Facts Label

During the low-fat craze of the late 1990s, consumers vigilantly monitored the fat content of their favorite food products with the mantra, less is more." At that time, only total fat and saturated fat were mandatory disclosures on the Nutrition Facts panel. In 2003, FDA mandated the disclosure of trans fat content on the Nutrition Facts panel, calling attention to the amount and types of fat in food. As nutrition research has evolved, consumers and manufacturers are starting to understand that some fats provide health benefits. But where are these good" fats on food labels? Have previous regulations caused us to focus more on which fats to avoid than which fats to encourage?

Many food manufacturers are now opting to include polyunsaturated and monounsaturated fat content on the Nutrition Facts panel, although disclosure is not mandatory. These manufacturers have chosen to show consumers the bigger picture of good fats within the diet and to help consumers understand their efforts to include healthier ingredients.

According to a recent webinar conducted by the Grocery Manufacturers Association, Washington, D.C., reform for the Nutrition Facts panel is underway. Mandatory and voluntary declaration of specific nutrients will likely be included in this discussion. When it comes to fats, we should consider requiring the declaration of polyunsaturated and monounsaturated fat content on the label. This would fall in line with research that shows many consumers prefer positive messaging (e.g., foods to encourage). How much detail should be included in the Nutrition Facts label? Should we break down good" fats even further into omega-3, 6 and 9 fatty acids? Should this be voluntary or mandatory? What are the benefits and drawbacks of adding this level of detail to the label and what impact would it have on consumer behavior?

Dave Dzisiak, global commercial leader, grains and oils, Dow AgroSciences

To respond to this piece or for more perspectives on label claims, visit the SupplySide® Community at supplysidecommunity.com.

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