How Energy Balance Works (Hint: It Isn't Just “Calories In, Calories Out”)

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September 22, 2022 — 10:02 AM

Fad diets come and go, but one popular phrase used (way too often) is “eat less, move more.” 

At some point in your life, you’ve probably heard some “expert” drone on about energy balance and cutting calories to lose weight. It’s important to be aware of where energy (aka calories) comes from—e.g., food, drinks, and even some supplements—and it’s equally important to consider how we burn energy. But energy balance and metabolism are more complicated than that.

If you’re tired of being held to outdated beliefs that “calories in, calories out” is the only approach to maintaining healthy body composition, keep reading to learn how to rev up your metabolic engine and support your body’s natural fat-burning power in a holistic, sustainable way.

While the “calories in, calories out” adage around healthy weight maintenance is outdated, it’s not because it’s wholly untrue. Rather, this overused cliché is vastly oversimplifying human metabolism.

Here are the three major ways your body expends energy (what we call “calories”) on a daily basis:

The first is resting energy expenditure (REE), which is the caloric requirement to simply “keep the lights on” with basic physiological functions. This includes making sure your organs are all doing their jobs (i.e., your lungs are breathing, your heart is beating and circulating blood, etc.). 

Your REE makes up 60 to 75% of the energy your body uses while at rest and is built into the more commonly known basal metabolic rate (BMR), which is affected by factors like age, sex, and activity level.

mindbodygreen’s vice president of scientific affairs Ashley Jordan Ferira, PhD, RDN, points out that there are also many metabolic variables not included in methods used to estimate BMR. These factors include:

• Genetics
• Body size & composition
• Specific health concerns (i.e., those that rapidly burn through energy)
• Thyroid health status
• Stress levels
• Sleep health
• Body temperature
• Gut microbiome
• The presence or absence of certain nutrients & botanicals in your diet

This next factor that affects your daily energy expenditure may seem obvious: The intensity and frequency of your movement each day plays a huge part in how many calories (i.e., how much energy) you burn each day.

By the way, when it comes to expending energy (i.e., burning calories), there’s one type of physical activity that reigns supreme: weightlifting. Lifting weights is an effective way to increase skeletal muscle mass, and skeletal mass burns more calories when the body is at rest than other tissues (like adipose tissue, aka fat).

Leptin is a hormone produced by fat cells. Its job is to communicate with the brain to maintain balanced fat stores. If there’s enough energy stored in fat, leptin messages the brain that the body doesn’t need to consume additional calories (energy). Ideally, the feedback response of the brain should cue a feeling of fullness.

According to registered dietitian Erin Skinner, M.S., R.D., LDN, IFNCP, simply increasing leptin levels should not be the goal when trying to maintain a healthy body composition. “The energy deficit caused by eating less and/or exercising more [paradoxically] lowers leptin, which increases appetite,” Skinner explains. Instead, people who struggle with maintaining a healthy weight should focus on a diet that improves leptin sensitivity.

Ferira adds that while losing body fat can lead to confusingly high hunger signals, each of these hormones plays more than one role in the body, and lowering leptin levels can actually be helpful sometimes.

Ghrelin (or as I like to think of it, growlin’) is the hunger hormone. This hormone is released when the stomach is empty and stops when the stomach is stretched. It’s highest before eating and lowest after eating.

Some people may not experience the same reduction in ghrelin levels, which can leave them feeling hungry all the time despite eating adequate food. What’s more, a person with a healthy (i.e., active) metabolism that ignores or misses ghrelin’s cues may experience a decrease in overall energy expenditure.

So, how can you learn to tune in to your body’s hunger signals? Working on mindfulness around hunger cues can take many forms. One way to start is waiting about 20 minutes after your first helping of a meal and then reflecting on whether you feel satiated.

If you feel satiated, great! Message received from your gut to your brain. If not, take a few moments to reflect on reasons why you may not feel full (and whether or not your meal included all the components of a well-rounded meal—i.e., healthy fats, complex carbohydrates, lean protein).

Other hormones worth mentioning include adiponectin (a hormone that promotes fat burn and healthy blood sugar levels), cortisol (the “stress” hormone), and thyroid hormones (aka the “master metabolism” hormones).

These hormones work in synchrony, despite being released from different areas of the body at different times in the digestion and absorption processes. You can learn more about metabolism hormones here.

Some of these plant-based ingredients that help support a healthy metabolism include veld grape, green tea extract (featuring EGCG), cayenne pepper, grains of paradise, and caffeine.* Together, these botanicals can help regulate leptin levels, increase your resting energy expenditure, activate brown fat tissue (the type of fat that burns calories), and enhance how well you utilize energy.* 

mbg’s metabolism+ is smartly designed to include all of these pure, plant-based ingredients, without any of the weird stuff. (So we can leave diet culture in the ’90s, once and for all.)  

I cannot stress this enough: Inadequate sleep and poor sleep quality are the root of so many metabolic health concerns. Aiming for seven to nine hours of quality sleep is a foundation of a healthy metabolism and overall well-being. In fact, insufficient sleep time and quality are associated with both increased ghrelin (remember, growlin’) and decreased leptin (fullness cue) levels, among a slew of other health concerns.

Think about what you crave when you’ve had a terrible night’s sleep or a few)—do you crave more processed carbs? How about sugar? Not getting enough shut-eye can lead to a series of different nutrition choices compared to when you’re well rested. Just a little food for thought.

Naturally, some people love working out. Others…well, not so much. Finding a type of movement that brings you joy is key and will encourage you to consistently choose action over inaction. If you can work out with a friend for accountability, even better!

That said, certain types of physical activity are certainly more efficient at burning calories (i.e., expending energy). According to Skinner, the best exercise plan for a healthy metabolism is to exercise around 150 minutes per week with an elevated heart rate, mostly in zone 2 (i.e., approximately 60 to 70% of your maximum heart rate). This may include weightlifting, dance classes, Pilates, fast-paced walking, or jogging.

Incorporating muscle-building exercises two to three times per week is also instrumental for balancing your metabolism, supporting healthy blood sugars, and increasing calories burned (even while you’re resting). 

One warning to heed: Too much high-intensity or endurance/cardio exercise can actually make your metabolic health worse, so balance your efforts with lower-intensity walking and other low-impact activities throughout the week to give your muscles a chance to recover.

Finally, don’t forget to give yourself grace. Habit formation doesn’t happen overnight, and building up your mental endurance is just as important as working on your physical well-being (if not more!). Plus, mental flexibility is a transferable skill that will support you in almost every aspect of life. (Win-win!)

You may be familiar with New York Times bestselling author Michael Pollan’s famous quote: “Eat food, not too much, mostly plants.” This is a great baseline strategy to work on your metabolic health; however, I worry people will perceive it as encouragement to undereat.

That said, Pollan’s succinct motto has some seriously valuable takeaways:

• Eating more fresh fruits and vegetables supports fullness and satiety, healthy bowel movements, and a healthy gut microbiome, thanks to their brightly colored antioxidants and fiber content.
• Whole foods that aren’t processed are rich in nutrients that are required for a healthy, functioning metabolism.

It’s not uncommon for people with a slow (i.e., less active) metabolism to also experience fluctuating blood lipid and blood sugar levels.

A simple and easy way to support healthy blood sugar and lipid status through nutrition is to make half your meal nonstarchy vegetables and divide the remaining half between starches (e.g., sweet potatoes, wild rice, fruit) and protein (plant-based or animal-based), plus 1 to 2 tablespoons of a healthy fat (think olive oil, grass-fed butter, or nut butter). 

Along with other nutrition and lifestyle habits that promote metabolic health, going for a two- to five-minute walk after meals can also be helpful in supporting post-meal blood sugar balance.

In the fast-paced world we’re living in, meals that are both calm and focused can feel like a distant memory. Not slowing down to look at, smell, thoroughly chew, and savor food is where many people begin to lose touch with their appetite cues.

Mealtime looks different for everyone and can vary based on when you eat. When it comes to timing, each person will have to experiment to figure out what works best for them at each stage of their life.

While not right for everyone, intermittent fasting with a 12- to 16-hour fasting window has been shown to improve body composition and metabolic markers over time. There are certain health concerns that may not benefit from intermittent fasting, so working with a knowledgeable health care practitioner who’s intimately familiar with your unique history and health needs is always recommended.

Tuning in to your hunger signals is also affected by who you’re sharing your meals with. People who aren’t aware of their own cues or distract you (we see you, parents!) may make it more challenging to sense your own hunger and fullness, while people who have figured out their own magic metabolism method may be able to pass on some tips and help you to learn new, healthy eating patterns.

Slow down, quiet the noise, and be open to receiving. This may be as simple as putting screens away at meals, avoiding working lunches (another tough one for many people), and having a little ritual or routine around meals.

Your hormones are complex, but there’s so much within your control.

If you’re confused about your own hunger cues or struggling to tune into them, you’re not alone. Consider partnering with an integrative health care provider who understands hormones and can help you get to the root of your metabolic health concern, so you can take the right steps to correct the course of your metabolic health.

Once you’re on the right track with your foundations, mbg’s metabolism+ may be a great addition to your metabolic health tool box.