Understanding TEF: The Thermic Effect of Food

What is TEF? The Thermic Effect of Food Explained

When it comes to fat loss, building muscle, or maintaining your physique, most people focus on two things: calories in and calories out. But what often gets overlooked is that even digesting food burns calories.

That’s where TEF comes in.

What is TEF?

TEF stands for Thermic Effect of Food.

It’s the amount of energy your body uses to digest, absorb, and process the nutrients in the food you eat. In other words, your body burns calories just to break down what you eat—and different foods require different amounts of energy to digest.

How Much Does TEF Contribute to Your Daily Calorie Burn?

TEF usually accounts for about 10% of your total daily energy expenditure (TDEE).

So, if you eat 2,000 calories in a day, around 200 calories are burned just processing that food.

It might not sound like much, but over time—especially when combined with movement (NEAT) and exercise—it adds up.

TEF by Macronutrient: Not All Foods Are Equal

Different macronutrients have different thermic effects. Here’s how they break down:

• Protein: 20–30% TEF — has the highest thermic effect
  
• Carbohydrates: 5–10% TEF — moderate thermic effect
  
• Fats: 0–3% TEF — lowest thermic effect

That means if you eat 100 calories of protein, your body burns 20–30 calories just digesting it. But if you eat 100 calories of fat, your body may only burn 0–3 calories during digestion.

Why TEF Matters for Fat Loss

If you’re trying to lose fat, increasing TEF can slightly boost your total calorie burn without extra effort.

While TEF alone won’t replace the benefits of exercise or movement, it’s a great support tool—especially when you optimize your diet with high-TEF foods.

High-protein diets are particularly effective for fat loss because they increase TEF, keep you fuller for longer, and help preserve lean muscle during a calorie deficit.

Can You Increase Your TEF?

Yes—and it starts with food choices. Here’s how to maximize your TEF:

1. Eat More Protein

• Include a lean protein source in every meal
• Helps preserve muscle, increases satiety, and raises TEF significantly

2. Minimize Processed Foods

• Whole, unprocessed foods take more energy to digest than refined, calorie-dense junk
• For example: brown rice vs. white rice, whole chicken vs. deli meat

3. Eat Meals Instead of Liquid Calories

• Your body works harder to digest solid foods
• Smoothies, juices, and shakes digest faster and burn fewer calories during processing

4. Space Out Meals

• Eating several balanced meals per day (rather than one or two huge meals) can support consistent TEF effects throughout the day

What TEF Is Not

It’s important to keep TEF in perspective. It’s not a license to eat more, and it’s not a magic fat-burning hack. You still need to be in a calorie deficit to lose fat—but TEF can help you:

• Burn a bit more throughout the day
• Feel fuller longer
• Maintain muscle while cutting calories

TEF won’t drastically speed up your metabolism, but when combined with a smart strategy that includes NEAT, exercise, and proper nutrition—it makes a real difference over time.

TEF and High-Protein Diets: A Powerful Combo

Here’s a practical example:

If you increase your protein intake from 15% of your diet to 30%, you’ll raise your TEF and preserve muscle mass—especially useful when dieting.

This is why many coaches (myself included) recommend a high-protein, whole-food approach for anyone looking to burn fat efficiently.

Final Thoughts: Don’t Ignore the Hidden Burn

The Thermic Effect of Food might be small, but it’s part of your metabolism puzzle—and when you're aiming to optimize fat loss or body composition, every bit counts.

By choosing smarter foods and balancing your meals, you’re not just eating to fuel your body—you’re eating in a way that helps you burn more calories, stay full longer, and support long-term results.

 
Want to see how TEF fits into your complete daily burn?
Check out my full breakdown of TDEE, BMR,EAT and NEAT—and learn how to use them to build a smarter fitness and nutrition strategy that actually works.