With countless health magazines and web articles displaying catchy titles such as “Boost Your Metabolism Now” or “Simple Foods for Effortless Fat Loss”, there’s no wonder Americans are on a relentless pursuit for that elusive “Metabolism Boost”. Before I can explain why these tips are filled with fluff and empty promises, first we must properly define metabolic rate.

What is Metabolic Rate?

The metabolic rate is simply the rate that chemical processes occur in your body and the energy that is needed for these processes to take place. It is common knowledge that if the body experiences a decrease in calories for a period of time the metabolic rate decreases to conserve energy. Let’s use Mary as a hypothetical example.

Enter Mary…

Mary decides she wants to diet to lose a few pounds; instead of eating 2,000 calories a day, as usual, she eats only 1,300 for several weeks. For the first couple of months this deficit of 700 calories seems to be working quite well, and she loses a couple of pounds; however, Mary is unaware that her body has recognized her diet as a “famine” and lowers leptin, a hormone which controls your metabolism by signaling your body fat levels: essentially, as your body fat falls so do your leptin levels and vice versa. As a result, Mary’s body responds by becoming more efficient with those 1,300 calories. If Mary were actually in a famine then this increased efficiency (a.k.a. a drop in metabolism) would actually save her life, but in our land of excess it goes against any dieter’s interest.

Things Can’t Get Much Worse for Mary.

Along with this drop in metabolism will likely come a myriad of unpleasant symptoms including constipation, fatigue, poor sleep, food cravings, and many others. However, an increase in appetite is the most menacing of these symptoms and ergo is the symptom most likely to sabotage Mary’s dream body. In fact, research suggests that “The body prompts us to eat about 100 calories more than usual for every 2 pounds or so of weight loss (Goodman, 2016).” For Mary, this means that if she ate 2,000 calories to feel satisfied pre-diet, and then went on to lose twenty pounds, she would then require around 3,000 calories just to feel the same satiety that she used to feel at 2,000.

Or Can They?

The worst part for Mary and her body is that they are now in what internet culture melodramatically calls “fat storage” mode and are likely to gain back all of the lost weight and more. Sorry Mary; don’t shoot the messenger.

So-called Metabolism “Boosting” Tips

Now let’s examine some of these metabolism “boosting” claims that one may come across while surfing the web or at the checkout counter of a local grocery store: caffeine, long cardio, green coffee extract, ice baths, chugging gallons of ice water, heck even our buddy Dr. Oz got in on the action by peddling Garcinia Cambogia. At this point, I know most of you are probably thinking, “this guy doesn’t know what he’s talking about, these do burn calories”. I totally agree that these burn calories, but don’t let them trick you into thinking that burning calories is the same as a boosting your metabolism.

Mary’s Fate

Whether you use these metabolism “boosting” tips or simply cut calories like poor Mary, the result is the same—a calorie deficit. As we saw in Mary’s example, a caloric deficit will never boost your metabolism, if anything it will slow it down. Ironically the best way for Mary to increase her metabolism would be to pig out on a dozen happy meals and a bag of Oreos. But Mary wouldn’t do that because she doesn’t want to get fat, do you Mary? Just picking on you Mary, whatever floats your boat we won’t judge…

References:

Goodman, B. (2016, October 14). How Your Appetite Can Sabotage Weight Loss. Retrieved from https://www.webmd.com/diet/news/20161014/how-your-appetite-can-sabotage-weight-loss#1