“…This research focuses directly on the behavioral and lifestyle factors related to weight gain in combination with socioeconomic status in the adult period, which includes decreased physical activity and unbalanced dietary intake. Even though there have been studies that blame SES (Goodman, Slap, & Huang, 2003), high fat diets (Racette, Deusinger, Strube, Highstein, & Deusinger, 2005;Saba, Vassallo, & Turrini, 2000), physical inactivity (Caspersen, Pereira, & Curran, 2000;MMWR, 2004), or media exposure (Dietz & Gortmaker, 1985;Yach, 2004) on gaining weight respectively, few studies have investigated the combined contributions of main factors on gaining weight of US adults all at once. Moreover, this study contributes to the literature because it uses the national representative sample to reaffirm the relationships between main contributing factors of gaining weight and corresponding measure of body mass index.…”