The American food supply may never be the same.
The recently passed ban of trans fats in restaurants in New York City signifies a potentially revolutionary step toward changing the way Americans eat, as cities like Chicago and Boston are now considering similar measures to regulate the food industry.
What are the facts about these fats that have public health officials up in arms? And most importantly, how could the ban and its sister regulation requiring calorie listings actually affect the health of those in the Big Apple and beyond?
After an unsuccessful year-long attempt to encourage voluntary elimination of trans fats at area restaurants, the New York City Health Department passed a ban this month that requires the city's 20,000 plus food vendors to switch to using almost all trans-free oils by July 2007.
Vendors have one more year after that to switch to margarine and shortening products with less than 0.5 grams trans fat per serving.
Also called trans fatty acids (TFA), trans fats are a type of fat that results from the chemical process of hydrogenation of unsaturated fatty acids. While TFA also occur naturally in small amounts in milk and meat products, the major sources of TFA in the American diet are products made with hydrogenated oils, including margarine, cakes, cookies and crackers, fried potatoes, chips and snacks, and household shortening (think Crisco).
Altogether, these sources of "artificial" TFA make up almost 80 percent of the trans intake of Americans, while the naturally occurring animal sources make up about 20 percent. The addition of hydrogen molecules to unsaturated fatty acids in plant oils gives trans fat its characteristic texture and shelf-stability that has led to its widespread use in the food industry.
New York health officials compared the fats to other public health hazards like asbestos and lead, concerns which arise from both population studies and recent clinical evidence showing that a high intake of trans fat is associated with increased risk of cardiovascular disease.
The research shows that trans fats increase both total and LDL ("bad") cholesterol levels, while lowering HDL ("good") cholesterol. High intake of TFA has also been associated with high blood triglyceride levels, another risk factor for cardiovascular disease. Besides raising cholesterol, the fats may support inflammation, the formation of blood clots, and insulin resistance, all factors associated with chronic diseases like heart disease.
The 2005 Dietary Guidelines for Americans recommend a minimal intake of trans fats to prevent chronic disease. Jen Weston, cardiology in-patient dietitian at Tufts-New England Medical Center, warns that food products containing trans fats "stay longer on the shelves and in our arteries."
"Fatty streaks [in arteries]," she says, "can appear as young as age seven." Weston also says that heart disease is not just something to think about when you turn 40, and she recommends choosing snacks and meals with little to no trans fat whenever possible. This means eating more natural, and fewer processed foods.
The New York City ban comes as just one (albeit major) step in a series of recent changes to reduce trans fats in the food supply and thus in the typical American diet.
Trans fat was first introduced in America in 1911 with a new product: Crisco shortening, made from hydrogenated cottonseed oil.
For much of the last half of the 20th century, margarines made with partially hydrogenated oils outsold butter. But as evidence surfaced suggesting the negative health risks of trans fats, the government, consumer groups, and the food industry itself began to change.
By 1999, consumers demanded change and there followed a decrease in the average trans fat content of margarines in America from about 19.5g per 100g in 1992 to about 8.8g per 100g. One consumer group, called Ban Trans Fats (see bantransfats.com) has taken such food giants as Kraft and McDonald's to court, demanding the use of healthier alternatives in food production.
In response, many food companies, including Starbucks and Wendy's, are voluntarily changing their menu items to offer nearly trans-free foods. With the 2003 FDA decision to require labeling of trans fat on packaged food, companies have begun to explore other ways to create shelf-stable products without the creation of trans fats during hydrogenation, including the use of tropical oils, which raises another health issue.
Decreasing the amount of trans fat in foods will not necessarily decrease the amount of fat or calories in them.
If chefs replace the trans fat with products like palm or coconut oils, the foods will still be high in saturated fat, the other type of fat linked with increased cholesterol levels and cardiovascular disease. Unsaturated fats, like those found in olive and canola oils, have been shown to be neutral or good for cardiovascular health, but they still contain the same number of calories per gram as trans fats, so if the same amount is used to replace trans fat, the calorie content of a food item will remain the same.
Many nutrition experts, including Dr. Alice Lichtenstein, Director of the Cardiovascular Nutrition Laboratory at the Jean Mayer USDA Human Nutrition Research Center on Aging, and Stanley N. Gershoff Professor of Nutrition Science and Policy at Friedman School of Nutrition Science and Policy, say the calorie issue is the real topic of concern since excess calorie intake leads to obesity, "the number one modifiable risk factor" for many chronic diseases including heart disease, diabetes, and cancer.
Since two-thirds of the American population is overweight or obese, Lichtenstein thinks there has been "an unfortunate amount of press toward the trans fat ban and not the calorie" labeling regulation that New York City health officials also just enacted.
This second regulation mandates that major food chains like Starbucks, Subway, and McDonald's display the calorie content of food items directly on menus or menu boards. While both regulations change the environment for New York eaters, the calorie lists also have the potential to change an individual's food choices.
Still, the interaction between individual and environment may not improve as a result of the approved initiative. Overall improvement will depend on how both the food industry and consumers react to the mandates. Whether trans fat and calorie labeling directives succeed or spread to other communities in America, improving the heart health of the nation as a whole, may require more change in the typical American diet. The use of more heart healthy fat sources and the consideration of total intake of calories, both in restaurants and at home, would help foster a healthier public.
