To hear what Kathy McManus has to say, you find yourself awake at dawn and scrambling to keep up as she takes her regular five-mile morning run. The pace never lags as she breakfasts, meets with patients in Boston’s Brigham and Women’s Hospital obesity clinic, brainstorms with a team of Harvard researchers, and teaches dietetic students about the role of nutrition in weight loss.
One of the architects of a landmark study on the importance of healthy fat in a weight-loss diet, McManus has witnessed time and again the fruitless efforts of motivated people who simply cannot lose weight and keep it off. She has also watched diet after trendy diet come and go, leaving behind a wake of frustration.
The experience has forged two basic principles for McManus: Unless food tastes good and satisfies, most people will abandon their diets; and an individual’s future weight and health depend on healthy weight loss, rather than on simply losing pounds.
In line with these precepts, she emphasizes the importance of individualizing diets. Counting calories and eating celery may work for some, she says, but not for everyone. In her own life, McManus is a vegetarian who strikes a balance between exercise and diet for maximum health. She loves good food, but approaches a five-course meal at an expensive French restaurant in the same way she does eating at the airport: seeking whole foods and reasonable portion sizes.
Q: You’re famous for a study in which fat became the key for people trying to lose weight. How was this groundbreaking?
For so long the presumed way to lose weight was to cut back on fat, an idea that took hold without much data to support the premise, especially in the long term. Our study helped demonstrate that people could eat healthy fat and still lose weight. In fact, the fat was what helped them stick with the regimen. Half of the volunteers spent 18 months on a typical low-fat diet (20 percent calories from fat). The other half followed a Mediterranean-style diet (35 percent calories from fat) in which monounsaturated fats (olive and canola oils and almonds, for example) were featured.
People lost weight on both diets, but after six months those in the low-fat group dropped out of the study at a greater rate because they couldn’t tolerate the restrictions. By the end of the study, even after we offered them $100 to come in simply to be weighed, many of them had completely abandoned us. In contrast, the Mediterranean group found the diet enjoyable, and many of them stuck with it after the study ended.
Food has to taste good. People who came into the study had been struggling unsuccessfully with their weight for a long time and had not eaten a nut or peanut butter in years. In the Mediterranean diet they could eat nuts, they could eat full-fat salad dressings, they could eat avocados—healthy, high-calorie foods they had been denying themselves. The key to their weight loss and follow-through was in portion control and including healthy fats.
Q: The Mediterranean diet is a far cry from the currently popular Atkins diet, another regimen in which fats get a green light. What can the Mediterranean diet do that a low-carb diet like Atkins cannot?
The Mediterranean diet can be used for healthy weight loss rather than simple weight loss. It cuts back on refined carbohydrates but makes room for healthy carbs from whole-grain sources, along with an abundance of fruits and vegetables. The Atkins diet may invite a little bit of fruit and vegetables back in, but it’s still low in the fiber and nutrients these provide. Also, saturated fat on the Atkins diet can be quite high, whereas on the Mediterranean diet it’s closer to 7 percent of calories. The average American’s intake of saturated fat is 12 to 13 percent—almost double.
Q: Atkins dieters hear this and say, “So what? I’m losing weight and to me that’s healthy.”
The problem is that we don’t know that the weight can stay off long-term. And we don’t know the implications of eating that way for the rest of your life: we have limited data on what the Atkins diet can do over a lifetime. Whereas we have more than 2,000 years of data that the Mediterranean diet can support health and long life.
Q: If someone is used to eating lots of processed foods, it must take a while for the palate to adjust to foods that fit into a healthy weight-loss diet.
Absolutely. This is not a quick fix. Rather it’s about biting the bullet and beginning to change eating patterns and build skills that are necessary to support them. In our study, the people on the Mediterranean diet began enjoying more vegetables and more fiber, two healthy results.
Q: Is that because on the Mediterranean diet they could use fats to make vegetables more flavorful?
Exactly. Instead of having simple steamed broccoli, they could stir-fry it with a little garlic and olive oil. With salad, a lot of people don’t like fat-free or low-fat salad dressings, but good olive oil enhances the flavor of salad. Even ranch dressing fits, as long as it uses a healthy fat like canola or olive oil as a base. If you eat fat-free salad dressings, you miss out on the beneficial linoleic acids in the oils. You can also sprinkle nuts on salad, instead of croutons, for crunch.
Q: Portion sizes are a top problem for your patients. Without measuring, how can I know whether I’ve chosen an appropriate portion?
Take a plate and divide it in half. Half of it should be vegetables, one-quarter should be lean protein, one-quarter should be whole grains.
Q: But there are different sizes of plates out there.
Yes, there are. But depending upon whether you are trying to lose weight or to maintain it, there are different approaches. To lose weight, take a smaller plate, but make sure the vegetables drape over the sides.
Q: What about snacking? How do I determine how many crackers are too many?
Pay attention to the serving size on the side of the package. Oftentimes what’s helpful is to combine a little bit of lean protein with the whole grain or the fruit: for example, have a little bit of low-fat tasty cheese, like string-cheese mozzarella, with an apple and a couple of whole-grain crackers; or have a little peanut butter or hummus on either fruits or vegetables or whole-grain crackers. Nuts also have protein, fiber and healthy fat.
Q: What does the combination of protein, whole grain and fat achieve?
It helps people, when they have that energy dip at 4:00 in the afternoon, to bring blood sugar up a little bit, but it’s not going to spike it—that’s good in the long run. If
you have more-refined snacks you’re good for a half hour
or hour but then you’re hungry again—you’re on that vicious cycle.
Q: Do you recommend supplements?
People who are trying to lose weight and who are cutting their calories should take a multivitamin, especially until they can get into healthy eating patterns. I also recommend that women take calcium with vitamin D.
Q: Do you think most people can lose weight healthfully and keep it off?
Oh yes. Call me Pollyanna but I do believe that people can make a difference in their lives and work toward goals. We do that every day in lots of different ways—and what better goal to work toward than health.
A day’s menu for Kathy McManus
Oatmeal or cold cereal (Kashi GoLEAN), with 1% milk, often a
few almonds, pecans or walnuts, and I always add fruit (strawberries, melon, oranges, banana). Sometimes whole-grain toast with peanut butter, but
no butter. Two cups of tea and at least six 8-ounce glasses of water (throughout the day).
A large salad of spinach leaves, vegetables, cottage cheese or a hard-boiled egg, dressed with oil and vinegar, with nuts sprinkled on top. Yogurt for calcium, and a piece of fruit, usually an apple.
Snack: An ounce of peanuts (28 peanuts).
A big stir-fry of veggies, frozen and fresh, with tofu and olive oil. Whole-grain pita, bread
or brown rice, and maybe another salad. I also make a lot of soups. In the summer it may be a cold squash soup or a gazpacho. I may have a glass of milk.
Dessert: A few times a week I’ll have some ice cream or a piece of dark chocolate.
Kathy McManus recommends:
"Eat, Drink, and Be Healthy" by Walter Willett
"Mediterranean Light" by Martha Rose Shulman