It's Your Body, Every Time

Thank you Donna Cravotta, Lynn L, Nancy Elise Pulliam, Patricia Lewis, Lola Strickland, and many others, for tuning in to my live video! Join me for my next live video in the app.

Every question today asks the same thing: was it my body, or was it my fault?

Reminder. This is education, not medical advice. Don’t ever change your care plan without talking to your doctor.

Also a big shoutout to Susan Brian MD. She is an academic endocrinologist who also runs clinical trials. She’s helping write the science I report. She’s here on Substack. Follow her. Subscribe to her.

LindaG asked:

“Fat cells not only grow bigger but also multiply, and when you lose weight, your fat cells shrink, but you don’t lose fat cells, they just get smaller. Is that part of the reason why those of us with lifelong weight struggles have to work so hard to keep weight off?”

Gaining fat does two things. Your existing fat cells get bigger, and you make more of them. Losing weight only causes the cells to shrink. The number of fat cells doesn’t change. After weight loss, the cell count remains the same, but the cells are not as full.

How much leptin a fat cell produces depends on its size. Leptin tells your brain you have enough fuel. Many small, underfilled fat cells release less leptin. With less leptin from the cells, your brain screams “scarcity,” making you hungrier, less full, and slowing your metabolism.

Adults do make new fat cells in cases of overfeeding or caloric excess. Fat cells have limited capacity. When the body needs to store more fuel, it creates new ones. This only happens in an energy surplus. Interestingly, new cells form mostly in the lower body: thighs, hips, buttocks. Upper body and abdominal fat tend to expand existing fat cells. One study showed that overfeeding led to 2.6 billion new cells in the lower body, while abdominal fat cells grew. In adult-onset obesity, there are more subcutaneous fat cells than in people who were never obese.

So yes. Part of the reason you work harder to keep the weight off is the decreased leptin signaling from your underfilled fat cells.

00:00 — Welcome and Office Hours
05:17 — Fat Cells, Leptin, and Weight Regain
14:22 — The Biggest Loser and Metabolic Adaptation
22:37 — Pregnancy, Set Point, and Gestational Diabetes
31:05 — HRT, Surgical Menopause, and GLP-1s
41:16 — Audience Q&A: Hormones, Gut Health, and GLP-1 Tolerance
46:49 — Wrap-Up and Telehealth Clinic Idea