Weight Loss, Metabolism and Setpoints: Slow & Steady, No Shortcuts

It’s a new year! Your pants are tight and you’re going through your mental list of realistic and maybe not-so-realistic New Year’s resolutions. Declutter. Donate your kids’ old toys and throw out those broken crayons. Spend less time looking at screens. Remove ham from fridge and replace it with kale.

Odds are that somewhere on that list is something about weight loss, clean eating, gym attendance or a new fitness regime that will finally deliver on its crazy promises: Lose 30 pounds in six weeks! Lose inches from your waistline by exercising only 18 minutes a day!

Jennifer Kirby, MD assistant professor of endocrinology and metabolism at UVA, hates to break it to you, but losing weight, as hard as it can be, is only half the battle. Maintaining weight loss is the longer game that doesn’t get you compliments from friends. But it can keep you from developing type 2 diabetes, metabolic syndrome, heart disease and other conditions associated with being overweight or obese.

Behavior, Genetics and Weight Loss

While the conventional wisdom tells us that moving more and eating less are the only things that achieve weight loss, the behavior factor is only one of many. “There is a huge genetic component, and things like environment, gut bacteria, what your mother was exposed to when she was pregnant with you — these things all factor into what your adult weight will be.”

Eating less and exercising more will definitely make you healthier. But Kirby believes that we have a lack of understanding about how active we really have to be.

What About Exercise?

“You can’t exercise to lose weight, but you can’t maintain weight loss without it,” Kirby says. “To keep weight off, you need a high energy expenditure.”

This means that it’s not enough just to exercise, but it’s being active too. For Kirby there’s a difference. “You can have two marathon runners. One is sedentary when he’s not running and the other is active and moves around a lot even when he’s not doing formal exercise. The more active one will have a lower risk for heart disease than the sedentary one.”

The good news is that a little activity can make a huge difference. “Walking at a brisk pace, with purpose, for 15 minutes after lunch can lower blood sugar. Using your large muscle groups makes insulin work better,” says Kirby.

If you can get in a few of these walks a day, even better. If you have a sedentary job, make a point of getting up and moving around every 30 minutes. Taking the stairs, walking a lap around the office or parking lot and getting into the habit of moving, in addition to whatever exercise you do, can prevent you from gaining weight back after weight loss.

Need a Sensible Weight Loss Plan?

Talk to your doctor.

Setpoints: They’re Real

If you feel like your body holds on to every excess pound, you’re right. “Our bodies defend weight, “ says Kirby.

There are hormonal and chemical signals being sent between the digestive system and the brain, and this feedback loop is where the setpoint — the weight that your body can consistently maintain without effort — comes in. When you try to change your setpoint, your body will fight it. That uncontrollable hunger isn’t your imagination or a lack of willpower. It’s your body fighting to maintain its current weight.

“It’s way more complicated than ‘eat less, exercise more,’ but doctors are still telling their patients that behavior is the whole picture,” says Kirby. “It’s a major factor, but when your body fights weight loss, you have to understand that this is physiological. Some people need medications or surgery to help them lose weight,” she says.

Doctors used to think that bariatric surgery worked by making the stomach smaller and achieving weight loss due to restricting the amount of food you could eat. However, in the years since the surgery first developed, researchers have found that it’s more complicated than that. “Bariatric surgery can change the gut bacteria and hormones, and this changes the body’s setpoint,” says Kirby. One day this might lead to the possibility of having weight loss without the surgery.

Health vs. the Numbers on the Scale

If you want to lose a bunch of weight just to look good, that’s one thing. But Kirby is concerned about the health of her patients. “A loss of 5-10 percent of your body weight can improve your health dramatically,” she says. She tells stories of patients who are still technically obese, but their risk factors have improved dramatically by losing 7 percent of their starting weight.

Looking at the whole picture doesn’t offer any shortcuts, but it also means that starting small can have a cumulative effect. “Do something small this week,” says Kirby. “Maybe get rid of soda during the week, or beer on the weekend. A slow, steady and modest weight loss can have a huge impact on your health.”