From pumpkin pie and mashed potatoes to eggnog and Christmas cookies, the holiday season is filled with delicious food, but it isn’t exactly great for our waistlines. The holiday excess might already have you thinking about that New Year’s diet. Dr. Dave Tschirley thinks about diets all the time, but not for himself. He’s with the Food Security Group in MSU's Department of Agricultural, Food and Resource Economics. They’re studying how the diets of people in Africa are changing dramatically as the continent becomes more urbanized.