Sorry, But "Metabolism-Boosting" Foods Are a Sham

For those interested in weight loss, the idea of metabolism-boosting foods may seem like the perfect solution. That’s because people often chalk up trouble losing weight to a slow, sluggish metabolism. If certain foods could make your metabolism run like a well-oiled machine, that might make weight loss a whole lot easier, right?

Well, if you’re getting ready to start Googling what foods help increase metabolism, hold up. Unfortunately, the science behind these so-called weight-loss superfoods — think: green tea, chili peppers, cacao, and apple cider vinegar — doesn’t quite stack up. Here’s what you need to know.

What does it mean to have a “fast” metabolism anyway?

To understand why foods that boost metabolism fast aren’t really a thing, it helps to know what your metabolism actually is and how it relates to weight loss.

“Metabolism is the term given to the multitude of chemical and physiological reactions required to turn food into usable and sustaining energy for the body,” explains Liz Wyosnick, a Seattle-based registered dietitian. In other words, your metabolism is the process your body goes through to use food to keep you alive.

The idea behind metabolism-boosting foods is that they “speed up” this process, potentially giving you the ability to eat more without gaining weight. In reality, a healthy metabolism is more about efficiency rather than "speed" — and food is only one of the many elements that impact your metabolism's efficiency, Wyosnick says.

Some of the others, she explains, include genetics, hormones, chronic health conditions, nutrient deficiencies, amount of lean muscle mass, current weight, dieting history, stress level, sleep, physical activity level...and the list goes on.

Plus, your metabolism’s efficiency is only one of literally hundreds of factors that impact whether or not you lose weight. Weight loss ultimately comes down to something called energy balance, or the relationship between calories coming into your body (like food) and calories going out of your body (like exercise). In order to lose weight, you’ve got to have more energy going out than coming in, which is referred to as a calorie deficit.

Okay, so are there any foods that help your metabolism?

Maybe. There’s research showing that all kinds of foods can increase your calorie burn (your energy out) — from coffee and tea to cacao and spicy foods that contain the chemical capsaicin, like chili peppers.

In principle, burning some extra calories through eating these foods could help you lose weight. But there’s a catch: “Even if you included more spicy foods, coffee, and green tea in a given day, perhaps the highest amount of extra calorie burn achieved would be 20 calories,” Wyosnick says.

So you’d have to eat a lot of these foods to create a meaningful calorie deficit. And at that point, the side effects of all the spicy food and caffeine probably won’t be worth it, she points out.

So what should you eat if you want to lose weight?

Now for some good news: There are some foods that can help you lose weight, partially by increasing metabolism. They just don’t work the way you might expect.

“One of the biggest factors within our control is to opt for food that is easily digested, assimilated, and excreted,” Wyosnick says. This basically means choosing foods that your body tolerates well, and that don’t tax your digestive or immune systems by causing sluggish digestion or inflammation. For example, if you know you’re lactose intolerant, avoiding dairy can help your body run more efficiently.

A good rule of thumb? “Whole, unprocessed foods are the stars here.” AKA foods with single or minimal ingredients.

Another good option is high-protein foods. Protein has the highest thermic effect of food compared to fat and carbohydrates, which means that it takes more calories to process and absorb, Wyosnick explains. That’s one of the reasons a high-protein diet is often recommended for weight loss. “But a better reason protein deserves a place in the discussion around supporting metabolism is that it’s highly satiating.” Protein helps you feel fuller for longer, which may translate into less snacking between meals, potentially smaller meals, and ultimately, fewer calories “in.”

Other helpful strategies for optimizing your metabolism have nothing to do with food. Wyosnick recommends:

• Prioritizing 7-8 hours of sleep each night and managing stress. “Ensuring that the body gets enough rest is key to supporting metabolism, because a stressed body tends to hold on to stored energy (fat) as a means of survival.”
• Exercising regularly, especially resistance and weight training. “Bodies with more lean muscle mass burn more calories at rest because muscle requires more energy.”
• Avoiding yo-yo and extreme dieting. “The body induces a survival mechanism to slow down metabolism at a certain point during significant weight loss. This is why gradual weight loss is best.”

The bottom line on metabolism-boosting foods:

According to Wyosnick, it’s best to focus on whole, minimally processed, and high-protein foods if you want to lose weight. And if you enjoy (and tolerate) coffee, green tea, and chili peppers? “They can certainly be part of your eating routine, but they shouldn’t be at the forefront of your weight-loss efforts.”