by Jennifer Drawbridge

Oh, hello there, Holidays, sneaking up on us with your festive, groaning buffets and the Ghost of Overeating Past. We see your gastro-guilt and raise you a nutrition expert who gives us the gift of this sound advice: Start thinking about the actual food you eat, and stop obsessing over calorie counts, which gets in the way of logical, healthy eating patterns.

"We're not just buckets to be filled with calories: 200 calories of broccoli is not the same as 200 calories of soda," says Dariush Mozaffarian, MD, DrPH, Dean of the Friedman School of Nutrition Science and Policy at Tufts University. "We need to start thinking of foods as levers that can turn on and off our body's inbuilt weight control mechanisms."

In an effort to identify some of the causes of weight gain, Mozaffarian and his colleagues reviewed the diet histories of more than 100,000 men and women. In their 2011 study published in the New England Journal of Medicine, they discovered that regular consumption of certain foods—white potatoes, sugar-sweetened drinks, and red meat—was strongly associated with packing on pounds. They also identified foods—vegetables, whole grains, fruits, nuts, and yogurt—that seem to protect against creeping weight gain. A follow-up study published this year corroborated their findings and found that a high intake of low-quality carbs decreased the protective effects of the foods associated with keeping pounds off and magnified the effects of foods associated with expanding waistlines.

How can we wrap all of this up in a holiday take-home package? Focus on filling your plate with the stuff that's good for you. "Short-term, any diet can help you lose weight, but to prevent weight gain in the long term, quality is key," says Mozaffarian. "If you eat more high-quality, nutritious foods, your very powerful inbuilt regulatory mechanisms that help prevent weight gain will kick in."

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