Can a Happy Relationship Lead to Weight Gain?: What Science Says
While some experts suggest that happy relationships can contribute to weight gain, the impact varies from person to person.
Does settling into a happy relationship come with a few extra pounds? A viral Instagram post by integrative doctor and self-described “biohacker” Kate Novaya, known as doctor.novik, claims it might. She explains that when women feel secure with their partners, stress hormone cortisol drops while oxytocin and serotonin rise. This shift prompts the body to relax, store energy, and possibly prepare for pregnancy—slowing metabolism and increasing appetite as a natural result.
Novaya’s post struck a chord online, sparking widespread debate. She argues that weight gain often accompanies healthy relationships, while significant weight loss could signal trouble—suggesting a 90% chance of an unhealthy dynamic. Social media responses were split: some nodded in agreement, while others insisted the opposite holds true.
The idea isn’t new. Couples often “grow together” over time, sometimes adding shared pounds along the way. Relatable social media clips—like Reels showing eating habits shifting from first dates to a year in—underscore this trend. As comfort grows, partners frequently mirror each other’s diets. For many, sharing food becomes a bonding ritual, with indulgences like extra fries slipping into routine.
But can weight really reveal a relationship’s health? Could those extra inches hint at a partner’s true colors?
Expert Insights: The Science of “Relationship Weight Gain”
Kushal Pal Singh, a fitness and performance expert at Anytime Fitness, says healthy relationships can indeed lead to weight gain, though it’s not universal. Research backs this up, showing happy, secure couples may lean into habits like more takeout, comfort foods, or less exercise. Singh points to the “relationship weight gain” hypothesis: once settled, people worry less about maintaining a certain physique than they did when single. Eating together and easing up on diet and fitness can tip the scales.
Here’s why this happens:
- Shifting Priorities: Early on, looking good often matters more. As security sets in, healthy eating and exercise can slide.
- Dining Out: Date nights at restaurants mean bigger portions and calorie-dense dishes.
- Alcohol Uptick: Socializing with a partner often includes drinks, piling on calories.
- Less Activity: Cozy time together can edge out workouts, leading to a sedentary shift.
- Synced Habits: Partners adapt to each other’s diets—skipping meals or choosing junk food can throw nutrition off track.
Dr. Rajiv Kovil, weight loss expert and head of diabetology at Zandra Healthcare, agrees new relationships might spark initial weight gain. Still, he stresses couples must prioritize a healthy lifestyle to keep it in check.
Hormones and Stress: A Balancing Act
Experts expand on Novaya’s hormonal angle. In happy relationships, feel-good hormones—oxytocin, dopamine, serotonin—flow freely, cutting stress and emotional eating. Lower cortisol helps regulate weight. But in toxic relationships, chronic stress can spike cortisol, fueling cravings and fat storage. Experts note weight gain should be temporary; persistent gains tied to high cortisol might flag deeper issues, echoing the viral phrase: “If your body rejects your partner.”
The Numbers: Newlyweds and Beyond
A study of over 8,000 people drives the point home. Married women gain an average of 24 pounds in their first five years of marriage. Cohabiting women add about 8 kg, while those in relationships but living apart gain roughly 6.8 kg. Men pack on pounds too, with little difference between married and cohabiting groups. Researchers say happy couples ease up on weight maintenance once they’re off the dating market.
The Takeaway
Newlyweds and fresh couples often see the scale creep up, thanks to hormonal shifts and lifestyle changes. But if you’re eating well and staying active yet still gaining, relationship stress could be the culprit—perhaps a cue to take a closer look.