Between 1865 and 1900, weighing oneself on a decorative parlor scale after a large meal surrounded by family and guests was considered a fun, novel past-time, says Deborah I. Levine, Ph.D., a Mellon Postdoctoral Fellow at Washington University in St. Louis who has researched diet, nutrition and obesity in 19th century America. How times have changed — when we got on the scale after the holidays, the mood was decidedly not celebratory.

These days, the scale can play an important role in weight loss and maintenance. The trick is to figure out what works for you, says American Dietetic Association spokeswoman Bonnie Taub-Dix, MA, RD, CDN. She recommends weighing in every Friday and Monday, since people often eat more on the weekends (an impending Monday trip to the scale might keep you in check) and a set schedule might give you a more accurate reading.

Just keep in mind that weight fluctuation is affected by many factors — including medication or salty foods. For example, if you’ve had a sushi dinner, you might weigh more the next day if you had salty soy sauce that causes water retention. “The numbers on the scale don’t always represent fat,” Taub-Dix says.

Do you have any tips to avoid an unhealthy scale obsession while trying to maintain a healthy weight?

Tags: America, American Dietetic Association, Body shape, Bonnie Taub-Dix, Cuisine, Deborah I. Levine, Food and drink, Force, Health/Medical/Pharmaceuticals, Hospitality/Recreation, Japanese cuisine, Mass, Nutrition, Obesity, Physics, Soy sauce, spokeswoman, Sushi, Washington University, Washington University in St. Louis, Weighing scale