Entries for April 2008

There's been a lot of debate over the past several years about whether you can be both fit and fat. That is, can you be overweight but as healthy as a lean person if you exercise regularly? A study released today in the Archives of Internal Medicine suggests that at least as far as heart disease in women goes, body weight and exercise are both important variables.

The discussion is complicated by the fact that the body mass index, the number researchers typically use to gauge overweight and obesity, is not always a perfect measure of body fatness. On one hand, because it simply relates weight to height, it may put musclebound but lean athletes into the "overweight" category. (Here's a study looking at its use in college athletes and nonathletes.) And as I wrote earlier this month, a low BMI may give some thin people a false sense of security, even though their percentage of body fat is high.

My friend was taken aback when she went to her local Starbucks in New York City for breakfast this week. According to the newly posted calorie counts on the menu, the scone she usually gets clocks in at more than 500 calories. She's now switching to a banana for breakfast.

The city has been embroiled in an ongoing legal battle with the New York State Restaurant Association about posting calorie counts in fast food restaurants. (See a collection of posts about the court case and the broader issue by NYU nutrition professor Marion Nestle here.)

Last week's issue of Us Weekly (yes, I subscribe) reported that Mariah Carey dropped 20 pounds by following a diet prescribed by her trainer/nutritionist. One key, the magazine said: a ban on eating carbohydrates and protein in the same meal, on the theory that because these nutrients are absorbed differently in the gut, eating them separately is more efficient and promotes greater weight loss than eating a more balanced meal.

I thought that Mariah probably lost the pounds because her diet (which actually looked pretty good—lots of fruit, veggies, lean protein, and good fats) provided only about 1,000 to 1,500 calories a day, not because the carbs and protein were allowed to schuss through the digestive tract without the benefit of each other's company. But I called nutritionists to find out if there was anything to the idea of separating nutrients by meal (which is actually an old one; William Howard Hay popularized the concept in the U.S. in the early 20th century).

When I'm in a blue funk, going for a run helps me feel a lot better. And prolonged periods of inactivity—say, after a big race—make me anxious, and something close to depressed. There are certainly a host of reasons why exercise seems to improve my mood (the Justin Timberlake on my iPod and the view from the Brooklyn Bridge, for example), but one potential factor is the idea, supported by a growing body of research, that physical exertion itself has a much bigger influence on the brain than previously thought. Just this week, a survey of existing research published by the Cochrane Library concluded that the same aerobic exercise that is good for your heart also improves cognitive function—specifically, motor function, auditory attention, and memory—in healthy older adults.

That's only one piece of what has become a burgeoning field. In Spark: The Revolutionary New Science of Exercise and the Brain, published earlier this year, psychiatrist John Ratey explores the neuroscience behind potential beneficial effects of aerobic exercise on anxiety, stress, depression, learning, aging, and even attention deficit disorder. (Research hasn't as fully explored the effects of anaerobic exercise or more passive activities like stretching and yoga.) "Even people who are overweight and who start exercising see improvements in mood and cognition in as little as 12 weeks," he says. One study found that exercise improved depression symptoms as well as medication.

A new poll published by Vegetarian Times finds that 3.2 percent of American adults say they're vegetarians. That's slightly up from a 2006 poll, when the number was 2.3 percent. (Both polls were conducted by Harris but on behalf of different organizations). The new poll also finds that about 10 percent of U.S. adults say they follow a "vegetarian inclined" diet. Those folks are also called flexitarians; they mostly eat veggies and plant protein but allow a little meat to cross their plates now and then. (Here's more info on flexitarian eating.)

People who avoid meat largely or in part because of concerns about animal welfare are probably not flexitarians, since that principle is pretty absolutist (thou shalt not kill and all that). But if you're primarily concerned about your own health, being a flexitarian is a great option; research has shown that nutrition is not an all-or-nothing proposition. The study out this week about the DASH diet shows that the closer you stick to an eating pattern that emphasizes fruits, veggies, whole grains, low-fat dairy, and nuts and legumes and goes lighter on red and processed meat, sweetened drinks, and sodium, the better off you are. Yes, the 20 percent of study participants who stuck most closely to the DASH diet saw the most benefits, but those in the 40th to 80th percentiles also saw their risk of heart disease drop. So you can have your occasional burger and your health, too.

I mentioned in a recent story on dietary patterns that promote good health, such as the Mediterranean and Asian styles of eating, that the Dietary Approaches to Stop Hypertension, or DASH, diet has been shown to lower blood pressure and improve blood cholesterol. Today, we point you to news that this kind of diet is also associated with a lower risk of cardiovascular disease and stroke among middle-aged women.

As I said in the dietary patterns story, the main difference between the DASH diet (heavy on the fruits, veggies, and plant proteins; light on animal protein) and the Mediterranean diet is that the Mediterranean diet is higher in fat, mostly "good" fats like olive oil and nuts. The authors of this latest study recommend further study of both diets to see which better predicts the risk of heart problems. For now, it's hard to argue that following the basic principles of either one will do anything but good.

Ask any nutritionist for some tips on a healthful diet, and the first or second thing out of her mouth will be "Eat more fruits and vegetables." Beverage manufacturers know that to consumers, fruit connotes health, which is why there are shelves and shelves of fruity drinks in your grocery store, deli, and even gym. But as Consumer Reports writes in its May issue, the word fruit can be awfully misleading. The magazine goes through what you're likely to see on the label of fruit drinks, and some of it may be surprising: A fruit "cocktail" drink, for example, might contain as little as 5 percent juice (with the other 95 percent from water, added flavorings, and sweeteners).

The Center for Science in the Public Interest published its own guide (.pdf) to health claims on fruit juice labels earlier this year, scrutinizing terms like "light," "antioxidants," and "omega-3s." What the CSPI mentions, and what many people don't know, is that even though it contains the important nutrients that diluted fruit drinks don't have, 100 percent juice has its downsides. The most obvious: Because it contains so much sugar, it's caloric. People who are looking to maintain or lose weight should really be drinking only two 4-ounce glasses a day, says Julie Miller Jones, a professor of family, consumer, and nutritional sciences at the College of St. Catherine in St. Paul, Minn. (I'd recommend you stop right now, go to the kitchen, and get out a liquid measuring cup to see what 4 ounces looks like. It's not much at all.)