Field Notes

Butter Is Not Back: Limiting Saturated Fat
Still Best for Heart Health

People who replace saturated fat in their diets with refined carbohydrates don’t lower their risk of heart disease, according to a new study led by researchers at Harvard T.H. Chan School of Public Health. On the other hand, those who replace saturated fats with unsaturated fats (found in vegetable oils and nuts) or whole grains lower their heart disease risk.

Many people fall back on carbs, especially refined carbs like white bread, when they reduce saturated fat in their diets, according to senior author Frank Hu, MD, PhD, MPH, a professor of nutrition and epidemiology at Harvard T.H. Chan School of Public Health. This may in part explain findings from a controversial 2014 study that called into question recommendations for limiting saturated fat for heart health, and led to headlines promoting the return of butter.

“Our research does not exonerate saturated fat,” Hu says. “In terms of heart disease risk, saturated fat and refined carbohydrates appear to be similarly unhealthful.”

The study was published in the October 16, 2015 issue of Journal of the American College of Cardiology.

This is the first prospective analysis to directly compare saturated fat with other types of fats and different types of carbohydrates in relation to heart disease risk.

Hu and colleagues looked at diet and health information from participants in two long-running observation studies, the Nurses’ Health Study (84,628 women) and the Health Professionals Follow-up Study (42,908 men), who were free of diabetes, cardiovascular disease, and cancer at baseline. Diet was assessed by food frequency questionnaires every four years. During follow-up, the researchers documented 7,667 cases of coronary heart disease (CHD).

They estimated that replacing 5% of energy intake from saturated fats with equivalent energy intake from either polyunsaturated fats, monounsaturated fats, or carbohydrates from whole grains was associated with 25%, 15%, and 9% lower risk of CHD, respectively. On the other hand, swapping 5% of saturated fat calories for the same amount of refined carbohydrates and sugars didn’t change CHD risk.

“In other words, refined carbs and sugars don’t lower CHD risk any more than saturated fats lower CHD risk (which they don’t),” according to Adela Hruby, PhD, MPH, cofirst author along with Yanping Li, both researchers in the department of nutrition at Harvard T.H. Chan School of Public Health. “People who choose refined carbs and sugars instead of saturated fat, thinking they're making a healthier choice, are not doing themselves any favors in terms of heart health.”

The study’s analyses took into account cardiovascular risk factors such as age, BMI, smoking, and physical activity.

“Our findings suggest that the low-fat, high-carb trends of the 1980s and 1990s are not effective in reducing risk of CHD,” Li says. “Dietary recommendations to reduce saturated fats should specify their replacement with unsaturated fats or with healthful carbohydrates, such as whole grains.”

— Source: Harvard T.H. Chan School of Public Health


Menu Calorie Counts Don’t Add Up
to Leaner Diets at Fast-Food Restaurants

Some six years out from New York City’s attempt to curb the obesity epidemic by mandating calorie counts in chain restaurants, researchers at New York University (NYU) Langone Medical Center have found that calorie labels, on their own, haven’t reduced the overall number of calories that fast-food consumers order and presumably eat.

In a report published in the November 2015 issue of the journal Health Affairs, the NYU Langone team describes its analysis of information gathered from 7,699 fast-food diners in New York City and nearby New Jersey cities.

The study, in which researchers compared food orders in places with and without calorie counts, is believed to be the first long-term analysis of the effects of menu labeling in the United States. Researchers say it also offers early evidence of its possible impact as the federal government prepares to introduce the policy nationwide in December 2016 as part of its Affordable Care Act.

Researchers found that the average number of calories bought by patrons at each sitting between January 2013 and June 2014 was statistically the same as those in a similar survey of 1,068 fast-food diners in 2008, when New York City initially imposed menu labeling. Diners were surveyed at major fast-food chains McDonald’s, Burger King, Kentucky Fried Chicken, and Wendy’s.

Calorie counts in the 2013-2014 analysis averaged between 804 and 839 kcal per meal at menu-labeled restaurants, and between 802 and 857 kcal per meal at nonlabeled eateries; whereas, they averaged 783 per meal for labeled restaurants, and 756 per meal for nonlabeled restaurants shortly after the policy was introduced.

For the surveys, diners entering the fast-food restaurant were asked to return their itemized receipts to research assistants and answer some follow-up questions in person in exchange for $2.

“Our study suggests that menu labeling, in particular at fast-food restaurants, will not on its own lead to any lasting reductions in calories consumed,” says study senior investigator Brian Elbel, PhD, an associate professor in the department of population health at NYU Langone and at the NYU Wagner Graduate School of Public Service.

Elbel says that while it’s important to acknowledge the limitations of the menu-labeling policy by itself, a combination of policies, such as marketing regulations or price subsidies for healthful foods, may have a positive impact on the nation’s obesity epidemic.

There’s still cause for optimism, he says, because the current and previous studies show at least some awareness of the bloated calorie counts in most fast food. “People are at least reading the information; some are even using it,” Elbel says, pointing out that among the study results from 2008, some 51% of survey respondents reported noticing the calorie counts, and 12% claimed that it influenced them to choose a lower-calorie item, even if it didn’t reduce overall caloric intake.

However, the number of people paying attention to the calorie counts diminishes over time. Elbel notes that at the start of the 2013 study, 45% of survey respondents said they noticed the calorie counts, a decrease from 2008 levels. As the study continued, this number dropped six months later to 41% and dropped again in 2014 to 37% in the last set of surveys.

An estimated one-third of adult Americans are obese (with a BMI of 30 or more), and that number is expected to rise to 42% by 2030, among the highest of any country in the developed world, he says.

Elbel says continued and closer monitoring of the impact of menu labeling also should boost success rates by showing more clearly where, for whom, and what kind of labeling shows the most promise. Potentially, he says, “labels may yet work at nonfast-food, family-style restaurant chains, or for specific groups of people with a greater need than most to consume fewer calories and eat more healthfully. We will have to wait and see, while continuing to monitor and analyze the policy’s impact.”

— Source: New York University Langone Medical Center