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Can You Have a Slow Metabolism?

In this episode, you'll learn what you can do if you’re one of those people who seems to “slow down” in response to a diet, and plateau quickly in terms of your weight loss.  

By
Ben Greenfield
4-minute read
Episode #235

In my book, “Get-Fit Guy’s Guide To Achieving Your Ideal Body Type,” I talk quite a bit about body types and metabolism—specifically highlighting the fact that each of the eight different body types can have a different metabolic rate, not to mention different exercise and nutrition needs.

Now, for the first time in a lab, researchers at the National Institutes of Health have discovered evidence supporting the fact that people with certain physiologies lose less weight, especially when on a calorie-restricted diet. In the study, researchers at the Phoenix Epidemiology and Clinical Research Branch looked at 12 men and women with obesity while inside something called a “metabolic chamber.” A metabolic chamber is a small room a person can live in for a 24-hour period, while their metabolic rate is measured during meals, sleep, and light activities. Scientists measure the heat released from a person's body to determine how much energy each activity has burned for that person.

Using a whole-room indirect calorimeter (which allows energy expenditure to be calculated based on air samples from the metabolic chamber), researchers took baseline measurements of each of the participants' energy expenditure in response to a day of fasting, and then had each subject follow a six-week phase of 50-percent calorie reduction.

MetabolismAfter accounting for age, sex, race, and initial weight, the researchers found that the people who lost the least weight during the calorie-reduced period also had a metabolism that decreased the most during fasting. In other words, the presence of a lack of calories from a diet actually caused some people’s biology to “slow down” more than others. Those people have what the researchers call a "thrifty" metabolism, compared to the "spendthrift" metabolism in those who lost the most weight and whose metabolism decreased the least.

So, what can you do if you’re one of those people who seems to “slow down” in response to a diet, and plateau quite quickly in terms of your weight loss? Here are a few quick and dirty tips:

 

Do Re-feeds

By having specific periods of the week or the day during which you eat a large meal or larger number of calories, you can keep your metabolism elevated and lose weight, and still avoid sending a signal to your body that calories are hard to come by. My recommendation to people doing big, voluminous (60 minute or longer) exercise sessions every day is to simply consume one large meal post-workout as your daily “re-feed.” In people only doing these type of big exercise sessions on certain days of the week, the goal should be to make those days of the week a day on which you have a larger “re-feed meal”. This isn’t a cheat day per se, in which you eat an ungodly amount of nasty foods like hamburgers and twinkies, but rather a day or meal where you eat more of the good stuff, such as seeds, nuts, fresh vegetables, sweet potatoes, yams, wild caught fish, grass-fed beef, etc. And OK, perhaps an extra chunk of dark chocolate.  

Exercise

This one should go without saying, but it really can be a factor in studies like this that look into metabolism. For the most part, engaging in physical activity frequently is going to be “the great equalizer” when it comes whether a diet works or not. If your metabolism tends to slow in response to calorie restriction, then you can simply keep it elevated through things like daily walks, a standing workstation, cold thermogenesis, weight training, and high intensity interval training, and you may need to do more of these type of activities than your neighbor on the same diet who seems to lose weight even when they’re lying around on the couch.

Try Calorie Cycling

My fellow podcast host Nutrition Diva has a great episode entitled, “How To Break A Weight Loss Plateau.” In it, she explains the concept of calorie cycling, in which you include higher calorie days to keep your metabolism from slowing in response to sustained calorie restriction. Calorie cycling is a little bit like a re-feed, but different because your total net calories taken in stays the same throughout the week. Instead, more calories are stacked on specific days. Nutrition Diva sums up the logic behind calorie cycling like this:

Get-fit Guy

“In order to lose weight, you need to cut back on your calorie intake. But if you do that for long enough, your body may play a nasty trick on you: It may start conserving energy by lowering your metabolic rate. The result? You don’t burn as many calories and your weight loss slows—or stops altogether. Although this feels like the worst kind of sabotage, your body is actually trying to look out for you. Your lizard brain has noticed that food supplies seem to have been scarce for an extended period of time. It’s trying to increase your chances of survival in case the famine continues. Of course, when you’re trying to lose weight, this is not very helpful.  You’re really stuck between a rock and a hard place: You could try eating even less in order to nudge off more weight, but that just confirms your lizard brain’s suspicions about the dwindling food supply. Or, you could eat more in an effort to restore a more robust metabolic rate—but that’s hardly going to help with weight loss. There’s a way to outsmart old lizard brain: It’s called calorie cycling.”

For example, you can alternate higher and lower intake days without reducing the total number of calories for the week, such as alternating 2,000-calorie days with 1,600-calorie days, for example. So, there’s no net reduction in calories, but the frequent switches keep your metabolism from slowing down.

While you may be fighting an uphill battle if you have a thrifty metabolism, try re-feeds, consistent exercise, and calorie cycling, and you’ll be well on your way to better weight loss success.

If you have more questions about whether you can have a slow metabolism, then leave your thoughts over at the Facebook.com/GetFitGuy page!

Metabolism image courtesy of Shutterstock.

About the Author

Ben Greenfield

Ben Greenfield received bachelor’s and master’s degrees from University of Idaho in sports science and exercise physiology; personal training and strength and conditioning certifications from the National Strength and Conditioning Association (NSCA); a sports nutrition certification from the International Society of Sports Nutrition (ISSN), an advanced bicycle fitting certification from Serotta. He has over 11 years’ experience in coaching professional, collegiate, and recreational athletes from all sports, and as helped hundreds of clients achieve weight loss and fitness success.