Your fruit isn’t so fresh. Take the apple. That one on your desk has likely been sitting in storage for months (tasty). So, to keep it looking fresh, it’s been treated with diphenylamine (DPA), a pesticide that doesn’t kill insects or fungal growths, but is designed to prevent fruit from developing brown or black patches.
This past March, the European Union issued what seemed, to many unaware of its proactive stance, like a very surprising statement. It would ban the importation of all apples containing the chemical, costing U.S apple growers $20 million in annual export sales. If Europe’s so worried, why aren’t we?
Introduced in 1962, DPA has been evaluated for safety several times, and subsequently deemed “unlikely to present a public health concern” by the World Health Organization. It does, however, have the potential to break down into carcinogenic nitrosamine after sitting on shelved apples for months post-harvest, according to a report by the Environmental Working Group. (Since the 1970s, the government has regulated products to prevent human exposure to nitrosamines.)
In a study by the pesticide’s manufacturers, researchers found three unknown chemicals on apples treated with DPA, but couldn’t determine whether any were nitrosamines. This unanswered question drove the European Commission to first ban DPA use on fruit grown within its own 28 member nations—and now to outlaw the import of any apples and pears containing more than 0.1 parts per million of DPA.
“Nobody has been able to identify any real risk from DPA, but Europe is trying to be on the prudent side,” says pesticide expert Carl Winter, a food toxicologist at the University of California–Davis. The Environmental Protection Agency, on the other hand, green-lights DPA residue of up to ten parts per million—a hundred times the new European standard.
But while Europe changed its stance, the Codex Committee on Pesticide Residues, and international regulatory group, hasn’t altered its regulations either, also setting them at ten parts per million.
Both the EPA and Codex—depending on who you ask—have consistently set careful standards for the safety of chemicals. And what we end up eating often contains much lower concentrations than the standards allow. A 2011 study by Winter’s team found that our typical exposure to DPA is 208 times lower than the established acceptable level.
Of course, there’s a catch: the EPA can license a chemical that hasn’t met all the requirements—such as those for comprehensive disease-testing—on the condition that the manufacturer follows up on its data after approval. But two separate studies from the Natural Resources Defense Council (NRDC) and the Government Accountability Office found that the EPA uses this conditional registration process more often than necessary, and doesn’t always review the follow-up data, which means pesticides have been approved without confirming that they pose no real risk.
And there are factors that the EPA overlooks. It doesn’t require testing against many of the more subtle and sensitive diseases, like hormone disruption and learning disabilities (many of which have been linked to pesticide exposure). It doesn’t account for exposure to multiple pesticides at once (such as in air and water). And it often doesn’t change regulations to reflect new studies——until that ten-year review date comes up, says Jennifer Sass, a senior scientist at the NRDC.
To ever call pesticides safe is likely a misnomer. “Pesticides are literally designed to kill organisms,” Sass points out. “What the EPA regulates is safety when used according to the label, not safety against all human diseases and effects.”
Unfortunately for consumers, while there’s a handful of studies suggesting that pesticide exposure can increase the risk of birth defects, respiratory illnesses, and cancer, there are far fewer studies analyzing the effect of merely eating chemical-covered produce.
Back to the big question: should the U.S. follow in the EU’s footsteps? Possibly. Many Americans—including the EWG—believe Europe’s decision should prompt the EPA to revisit the pesticide’s safety. But, as Winter explains, since all growers outside Europe follow the international standard of ten parts per million, doing so would have a huge impact on international trade.
Regardless of the U.S.’s actions, do keep eating those apples. “The health benefits of consuming fruits and vegetables far outweigh any potential risks from these chemicals,” says Ruth MacDonald, a registered dietitian who chairs the Food Science and Human Nutrition department at Iowa State University. If you have the financial means and the drive to buy organic, go for it—but don’t stop eating apples just because they have pesticides on them.
Since its release in theaters on May 2, the anti-“Big Food” documentary Fed Up has received plenty of media attention and praise. Through stories and expert commentary, the film, narrated by Katie Couric, strives to bring attention to the underlying causes of youth obesity—and places the blame squarely on added sugars. For this reason, New York Times food writer Mark Bittman called it “probably the most important movie to be made since An Inconvenient Truth.”
Given the accolades, it’s hard to imagine detractors, but remarks of disapproval keep coming, including from spokespeople at both the American Society for Nutrition (ASN) and Academy of Nutrition and Dietetics (AND), who focus on the documentary’s one-sided and sugar-obsessed take on obesity. Beyond stigmatizing a nutrient that’s critical to fueling exercise—and has repeatedly been shown to enhance athletic performance—Fed Up falls short on emphasizing the role of other calorie sources in weight gain, and it discounts one of the most powerful tools in the war on obesity: physical activity.
While added sugars are a significant part of the problem because they are widely used to make food appetizing, they are far from the whole problem, says Dr. David Katz, director of Yale University’s Prevention Research Center and listed as a member of the scientific advisory board for Fed Up. “In terms of overall health outcomes, the evidence overwhelmingly indicates the conjoined importance of what we do with our forks and what we do with our feet,” he says.
If Dr. Katz is straightforward in his criticism, he is joined by many other nutrition experts and organizations who have taken a harder line against the film. Angela Lemond, a registered dietitian nutritionist and AND spokesperson, says that the film’s minimizing of the benefits of exercise is “truly unfortunate” and “irresponsible,” noting that sugar is a quickly absorbed source of carbohydrate that is crucial for exercise performance. Moreover, the film’s focus on sugar as a major factor in contributing to obesity is a “biased view” not shared by the majority of objective scientists, says James O. Hill, a professor of pediatrics and medicine at the University of Colorado, Denver and an ASN spokesperson.
“Research is clear now that adding sugar to a diet and taking away the same number of calories does not cause weight gain or any other of the outcomes attributed to sugar in this film,” Hill says.
But Hill’s chief criticism of the film is the absence of any expert on physical activity. Based on his own research at the National Weight Control Registry, which he founded, an hour or more of physical activity per day is key for long-term weight management success. The registry follows more than 6,000 formerly obese people who have succeeded in keeping weight off permanently. Regardless of how many calories that activity burns, the reason an hour or more of daily exercise works may be due to a change in the body’s biology that helps control appetite and food intake, Hill explains.
While Fed Up blames rising obesity rates on sugar, consumption of added sugars has actually fallen by a quarter over the past decade, with most of the reduction coming from a decline in sugar-sweetened beverages, according to national survey data, says ASN spokesperson Dr. Roger Clemens, chief science officer for specialty ingredient supplier E.T. Horn Company. He also served on the USDA 2010 Dietary Guidelines Advisory Committee. Dr. Clemens says that Fed Up “misconstrues the evidence from many studies and confuses customers” about the role of sugar and processed foods in promoting obesity.
As an avid cyclist who enjoys a regular 50-mile ride, Dr. Clemens stresses the role of sugars in fueling exercise. His own sports drink and exercise fuel of choice: orange juice plus peanut butter and jelly sandwiches. He also says the film doesn’t take into account that exercise will help improve the way sugar is handled in the body through improved insulin sensitivity. Guidelines on sugar intake for active versus nonactive people should not be the same, he says.
While Fed Up has done much to reignite the national debate on obesity and sugar, it’s crucial to separate fact from narrative function. Active people and athletes need sugar to perform. When it comes to obesity, no single nutrient should take all the blame. When it comes to weight loss, a focus on the whole diet is necessary and exercise remains key.
“For health, [exercise is] essential—elemental. The importance cannot be overstated,” says Dr. Katz. “For weight maintenance, also vital; for weight loss per se, diet matters more just because it is so much easier to out-eat exercise than to out-exercise an unregulated intake of calories.”
All athletes follow (or at least are aware of) the same nutritional guidelines: drink a protein shake within an hour—at most—after working out. It’s the same token of advice we’ve been hearing for years. But does it still hold true? It may be time for the rules of protein—namely, quality and timing—to be rewritten.
The workout window still stands, but not quite as rigidly as before.
The first two hours after a workout are still the most important, but not just because of protein. “When you exercise, your reserve of protein, carbohydrates, and amino acids are depleted while your hormones—cortisol, testosterone, and growth hormone—spike,” says Richard Kreider, director of the Exercise & Sport Nutrition Lab at Texas A&M University. Low nutrient pools and high hormones put your body in the optimal position to synthesize protein and carbs, speeding recovery and encouraging muscle growth, he explains.
But a landmark meta-analysis last year in the Journal of the International Society of Sports Nutrition revealed that the window is influenced more by your pre-workout meal than the workout itself. Researchers found that timing your pre- and post-exercise meals to be within three to four hours of one another was more important to muscle growth and recovery than any post-workout window alone.
“Not only does this support that the window is substantially wider than previously believed, but other research has shown that muscle is sensitized to protein intake for at least around 24 hours post-workout,” says study author Brad Schoenfeld, a certified strength and conditioning specialist who directs the Human Performance Lab at CUNY’s Lehman College in New York. “This doesn't mean that there is no benefit to ingesting protein sooner, but you will continue to see benefits of consuming protein long after the workout is finished.”
Whey has long been held as the gold standard. It releases a higher level of amino acids faster than all other proteins, triggering protein synthesis—which turns on the muscle-building effect, explains Jacob Wilson, a certified strength and conditioning specialist and director of the Human Performance and Sports Nutrition Lab at the University of Tampa.
But other sources are making strong cases for recognition. A new study from University of Texas Medical Branch found that a blend of soy, casein, and whey prolongs the delivery of nutrients after a workout, enhancing muscle recovery and growth better than whey alone can. And a 2013 study in Nutrition Journal found that rice protein was just as effective as whey in trimming fat and increasing lean body mass, muscle mass, strength, and power.
There may be merit to these results—but the research is still in its infancy, whereas the benefits of whey are long-established, amplifies Wilson. As for protein powders themselves, their main advantage over whole food is unarguably one of convenience. Time constraints shouldn’t mean you’re not going to get proper protein and carbohydrates throughout the day, and shakes offer a solution, offers Kreider.
Except for their isolates, protein powders are, in essence, derived from whole foods, adds David Grotto, a registered dietitian and author of The Best Things You Can Eat. That said, on a diet of shakes, you’ll miss out on other nutrients—like fiber and iron—that are found only in whole foods and that might be critically important to the body and even to aiding recovery, he explains.
The bottom line? The advice for optimal protein quality and timing is, in fact, a mix of old and new thinking. Post-workout protein and daily protein need to be working hand in hand, says Kreider. And, as far as what to eat, stick to a fast-digesting protein shake after a workout and high-quality whole-food proteins—like lean chicken, eggs, Greek yogurt, soy milk—with every meal and, in smaller amounts, with every snack, recommends Grotto.
Red wine and chocolate might not be as good for us as we were hoping.
Though people often use the purported health benefits of antioxidants in grapes, chocolate, and red wine as an excuse to indulge, a recent study has found that the antioxidant resveratrol has no association with cancer and inflammation, the incidence of cardiovascular disease, or longevity.
“Studies using mice and cell cultures suggested that resveratrol might be protective for health and extend lifespan,” says Dr. Richard Semba of Johns Hopkins University, the lead researcher on the study. “The idea that higher resveratrol levels are protective against heart disease and cancer, and might make people live longer had never seriously been examined in humans until we did our study.”
For years, the so-called “French Paradox”—a diet high in cholesterol and saturated fat, yet a low incidence of coronary heart disease—has been chalked up to regular glasses of red wine, and resveratrol specifically. To test out the theory, Semba and his team conducted the Aging in the Chianti Region study from 1998 to 2009. They studied 783 men and women 65 years and older from two Italian villages to determine what effects resveratrol might have on inflammation, cancer, cardiovascular disease, and death.
Over the course of the nine-year study, 286 participants—more than one third—died. More than 27 percent of those who started the study without cardiovascular disease developed it, and four percent of those who started the study without cancer had it by the study’s end. Resveratrol had no correlation with cancer rates, inflammation, cardiovascular disease or death. It’s possible that instead, the French Paradox may be attributed to higher levels of exercise, Semba says.
In the meantime, the news doesn’t mean you have to avoid red wine. Studies have found that a glass or two of red wine “can provide some protection against heart disease,” he says. “People should not be discouraged from having a glass of wine with a meal, as it can make the meal more enjoyable. Wine is a very complex beverage. Resveratrol is only one of the few dozen polyphenols in wine.”