According to Dr. Christopher McGowan, an obesity-medicine specialist who spoke with Health.com, many adults gain about a pound between late November and early January.
He notes that the combination of celebratory meals, buffet-style gatherings, and foods prepared by others makes it harder to keep track of portions or calories.
Nutrition specialist Dr. Amy Lee added that busy schedules often push people toward restaurant meals or convenience snacks, which can unintentionally increase daily intake.
At the same time, colder mornings and dark evenings tend to derail outdoor workouts, leaving many people less active than they are in warmer months.
Also read: Research shows bedtime stability may help lower blood pressure
When higher-calorie meals meet fewer opportunities to move, weight gain becomes more likely, Christopher McGowan said.
Seasonal biology and mood
Winter also affects mood and appetite in ways that can influence eating habits.
Emma Laing, a dietetics expert also quoted by Health.com, explained that seasonal shifts in hormones may contribute to changes in energy, hunger, or cravings.
Shorter days can disrupt sleep patterns, which in turn increase appetite and lower motivation to exercise.
Also read: Scientists explain how much water a healthy body can process safely
For some people, symptoms of seasonal affective disorder, such as fatigue, low mood, or increased drinking, can further weaken healthy routines, said weight loss specialist Dr. Sue Decotiis to Health.com.
These factors don’t slow metabolism dramatically, she emphasized, but they can make healthy choices feel harder.
Practical ways to stay on track
Experts agreed that planning ahead can make winter more manageable.
Dr. Sue Decotiis recommends eating a small protein-rich snack before holiday events to avoid arriving hungry.
Also read: Researchers identify unexpected age effects in cancer formation
Dr. Christopher McGowan suggested getting outside briefly during daylight hours to help maintain energy and mood, and using indoor options, such as treadmills, gyms, or online workout videos, when the weather is harsh.
While winter presents challenges, consistent activity and mindful eating can still prevent seasonal weight gain.
Sources: Health.com.
Also read: She drank olive oil for two weeks – here’s what happened
Also read: Study shows cold feels different depending on the time of day