How to Fix a Slow Metabolism (and Avoid the Mistakes That Make It Worse)

Metabolism is your body’s engine. It powers everything from your energy levels to how efficiently you burn calories, even when you are at rest. If your metabolism feels sluggish, don’t worry. This guide will make it easy for you to understand how to raise it effectively.

Think of your metabolism like a bank account. Every choice you make is either a deposit or a withdrawal. The goal is to make consistent deposits by building muscle, eating balanced meals, and prioritizing sleep. These actions keep your body burning calories efficiently and working for you, not against you.

Let me tell you about my friend Sarah, who struggled with her metabolism bank account for years before she learned how to rebuild it.

Sarah and Her Metabolism: A Walk Down Memory Lane

My friend (let’s call her Sarah) is a perfect example. Sarah and I went to junior high together, and I’ll admit, I had a huge crush on her back then. She was kind, funny, and effortlessly beautiful.

When we got to high school, we became close friends. We never dated— I was very shy and she seemed to go for the more popular guys, but I ended up hanging out at her house a few times. Getting to know her. She was definitely someone you could look up to.

Sarah was the type of girl everyone admired. I remember frequently hearing people in the halls talking about how pretty she was or how fit she was—girls wanting to look like she looked and guys wanting to date her.

Sarah wasn’t just attractive—she was strong. Her parents were both in great shape and she worked out with her dad from the time she was 14 until the end of high school, and she stayed lean and athletic.

Sarah could also eat more than you’d expect. She even out-ate me a couple of times, and that’s saying something. I was a growing teenage boy. Her metabolism seemed superhuman, burning through whatever she ate and keeping her effortlessly slim.

That’s why I was so surprised to see Sarah “let herself go” after high school.

What Changed After High School?

After high school, Sarah stopped going to the gym or hiking like she used to. Her active lifestyle, which had kept her metabolism running smoothly, came to a halt.

She became more of a homebody, spending most of her time indoors. Without regular sunlight, her vitamin D levels (important for metabolic health) likely dropped, and her energy levels did too.

From Sarah’s perspective, she probably didn’t think much had changed. But in high school, she was much more active, and her meals were prepared by her parents, who cooked balanced dishes with lean proteins, vegetables, and whole grains.

As an adult, Sarah wasn’t cooking much. Instead, she was eating food that came out of packaging, such as quick, convenient meals that were high in calories but low in nutrients. These foods didn’t fill her up, so she often ate more than she realized.

Imagine your metabolism bank account getting constant withdrawals.

Less movement, nutrient-poor foods, and more stress slowly drained her balance until it became harder and harder to recover.

The Diet Mistakes That Tanked Sarah’s Metabolism

Fast forward 25 years since we graduated, and Sarah and I stayed in touch.

Over the years, I saw her confidence drop as her weight increased.

Then, last year, we had a real conversation about health and fitness.

After seeing all my progress going from dad bod to 6-pack shredded, Sarah told me she had tried every diet she could think of, but nothing seemed to work.

She was stuck in a cycle of yo-yo dieting, where extreme restrictions led to temporary weight loss, followed by weight regain (and often more).

Here’s what I explained to her:

Yo-Yo Dieting: A Metabolism Killer

Every time Sarah started a new diet, she pushed her body into extremes, like cutting calories too low or eliminating entire food groups.

This pattern is a metabolism killer:

Muscle Loss: Extreme calorie cuts force your body to burn muscle for energy. Less muscle means a slower metabolism.
Metabolic Adaptation: Your body becomes efficient at burning fewer calories, making it harder to lose weight over time.
Increased Cortisol: Strict dieting raises stress hormones, which signal your body to store fat, especially around your belly.

Think of yo-yo dieting as repeatedly overdrawing your metabolism bank account. Each time you try an extreme fix, your balance gets worse.

How Sarah Fixed Her Metabolism

After years of trial and error, Sarah finally turned things around by focusing on making deposits into her metabolism bank account. Here’s what worked:

Build Muscle: Muscle is the foundation of your metabolism. The more muscle you have, the more calories you burn, even at rest.
- Sarah started lifting weights three to four times a week, focusing on compound movements like squats, deadlifts, and bench presses.
- At first, she was intimidated by the gym, it had been years, but quickly gained confidence as her strength improved.
- Research shows that every pound of muscle burns approximately six to ten calories per day at rest, compared to two to three calories for fat.
Balance Macronutrients: Instead of extreme carb-cutting or fat-avoidance, Sarah learned to eat a balanced diet:
- Protein: Essential for muscle repair and metabolism. She found out that she was eating a fraction of her necessary protein each day.
- Carbs: Provide energy and reduce cortisol levels.
- Fats: Support hormone production, which regulates metabolism.
Stop Under-Eating!: Sarah had a habit of eating too little during the week and overeating on weekends. I showed her how to fuel her body consistently with the right portions. Instead of skipping breakfast, she started eating 6 eggs every morning. Once she stopped starving herself, her metabolism started working with her again.
Prioritize Recovery: Stress and poor sleep had been sabotaging Sarah’s progress. She started getting seven to eight hours of sleep each night and used daily walks to manage stress. Lower cortisol levels meant better metabolic function.

Metabolism Changers: A Quick Summary

Here’s the cheat sheet Sarah (and now you) can use to boost metabolism:

Build Muscle: Lift weights three to four times a week to increase your calorie burn.
Eat Protein with Every Meal: 30g-60g is a good goal. Protein builds muscle and keeps you full longer.
Add Healthy Carbs and Fats: Fuel your body with energy and support hormone health.
Stay Consistent: Avoid extreme calorie cuts and yo-yo dieting.
Manage Stress: Take walks and prioritize mindfulness to lower cortisol levels.
Sleep Seven to Eight Hours: Quality sleep is essential for recovery and metabolism.

Think of these habits as deposits into your metabolism bank account. Each one strengthens your balance and keeps your metabolism working efficiently.

Sarah’s Transformation

Within weeks, Sarah felt more energetic and noticed her clothes fitting better.

After just a couple months, she was stronger, sleeping better, and keeping up with her kids. Most importantly, she felt more confident and in control again.

Today, about a year later Sarah updated her Facebook profile picture and she looks so great. Reminds me of when we went to school together. And probably the most attractive thing about this new profile picture is the confidence in her eyes. I’m so impressed with what Sarah was able to accomplish.

Start Simple, Start Today

Take one small step today:

Go for a ten-minute walk after your next meal.
Add a serving of protein to your plate.
Plan to strength train at least once this week.

Your metabolism isn’t your enemy. It’s your greatest ally, and the more deposits you make, the better it will work for you. Take care of it, and it will take care of you.