A prospective study of holiday weight gain

Area of Science:

• Nutrition Science
• Human Physiology
• Public Health

Background:

• Common assertion: Americans gain 5 lb (2.3 kg) or more during the holiday season.
• Lack of empirical data to support widespread holiday weight gain claims.
• Need for accurate data on seasonal weight fluctuations.

Purpose of the Study:

• To quantify actual weight changes during the holiday period.
• To determine if holiday weight gain is temporary or cumulative.
• To investigate seasonal patterns of body weight variation.

Main Methods:

• Body weight measurements in 195 adults across four time points (preholiday, holiday, postholiday, and follow-up).
• Weight change analysis for distinct seasonal periods: preholiday, holiday, and postholiday.
• Long-term follow-up in 165 subjects to assess sustained weight changes.

Main Results:

• Significant mean weight gain of 0.37 kg (P<0.001) during the holiday period.
• No significant weight change during preholiday or postholiday periods.
• Average net weight gain of 0.48 kg from fall/winter to late winter/early spring (P=0.003).

Conclusions:

• Average holiday weight gain is substantially less than commonly asserted.
• The observed weight gain is not reversed in spring/summer, suggesting cumulative effects.
• The modest fall/winter weight gain likely contributes to gradual adult weight increase over time.