Think you know what it takes to keep weight off? Most people can tell you how to lose weight, but ask them what actually predicts keeping it off, and the answers get shaky fast. That’s a problem, because losing weight and maintaining weight loss are two completely different biological and behavioral games, and confusing the two is one of the biggest reasons people yo-yo.

In this episode, Holly and Jim put their listeners to the test literally. They’ve built a 20-question pop quiz covering everything from the hidden biology of metabolic adaptation to the real findings from the National Weight Control Registry, the groundbreaking study Jim co-founded three decades ago. And because so much has changed recently, they’re also tackling the question everyone’s asking: does any of this still apply in the age of GLP-1 medications?

Grab a pen (or play along in your head) and see how many you get right. Some answers might surprise you, and a few might change how you think about your own weight loss journey for good.

Discussed on the episode:

• Why the biology of losing weight and the biology of keeping it off are two entirely different processes, and why not knowing this is setting you up to regain
• What really happens to your metabolism after weight loss, and whether “metabolic adaptation” is something you should actually be worried about
• The hunger hormone changes that don’t go away and what that means for your day-to-day life
• The real math behind the “energy gap,” a concept Jim and Holly coined themselves
• What the National Weight Control Registry’s 30,000+ members actually do differently, including the surprisingly unglamorous form of exercise most of them rely on
• Whether successful maintainers take weekends and holidays “off” from their habits
• The truth behind the infamous “95% of diets fail” statistic.
• Whether losing weight slowly really does make you more likely to keep it off.
• Why willpower isn’t the key predictor of long-term success and what is
• What happens to the body when someone stops taking a GLP-1 medication, and whether that counts as the medication “failing”
• The most vulnerable window for regain during medication-assisted weight loss and why most people prepare for the wrong phase
• A rapid-fire round covering daily weighing, running vs. walking, and the most overrated maintenance strategy out there