Why Is Body Language Important? The 3 Key Reasons

This article is an excerpt from the Shortform book guide to "The Definitive Book of Body Language" by Allan Pease and Barbara Pease. Shortform has the world's best summaries and analyses of books you should be reading.

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Why is body language important? What are the three major reasons?

In The Definitive Book of Body Language, Allan and Barbara Pease delve into the captivating world of nonverbal cues. The authors explain the profound impact body language can have on your emotions, interpersonal relationships, and overall communication skills.

Read on to learn three main reasons why body language is important, according to Allan and Barbara Pease.

The Importance of Body Language

Why is body language important? According to Allan and Barbara Pease, who wrote The Definitive Book of Body Language, there are three key principles of body language that underscore why it’s so important:

Your body language both reflects and influences your emotions.

Your body language influences how people feel about you and interpret your words.

Awareness of your body language helps you control your emotions and the way others respond to you.

Let’s explore each of these principles to learn exactly why body language is so important.

#1: Your Body Language Reflects and Influences Your Emotions

Allan and Barbara Pease argue that your body language—your facial expressions, gestures, and posture—always reflects your emotions, which is the first reason why understanding body language is important. They explain that there’s a strong physiological link between your emotions and your body language. This link is bidirectional: Your emotions trigger physiological responses that get reflected in your body language, and your body language, in turn, influences your emotions and physiological responses.

Let’s explore this two-way relationship in more detail.

It Reflects Your Emotions

According to the authors, each time you experience an emotion, your brain sends a signal to your body to produce a physiological response. These responses include changes to your heart or breathing rate, your blood pressure, your muscle tension, and your hormone levels. Each of these physiological changes then creates a corresponding physical response—and each physical response signals to others what you’re feeling.

Example: When you feel angry, your body releases stress hormones that cause your heart and breathing rate to increase and your muscles to tense up. These physiological changes create corresponding physical responses—for instance, your face reddens, your jaw feels tight, your fists clench, and your tone of voice becomes louder. Each of these physical responses signals to others that you are angry.

It Influences Your Emotions

In addition to reflecting your emotions, another reason why your body language is important is because it also influences your emotions. Allan and Barbara Pease explain that your physical movements—facial expressions, gestures, posture—also create physiological responses in your body. Each of these physiological responses creates a corresponding emotional response.

Example: When you smile, your body releases endorphins that help to lower your heart rate and relax your muscles. Each of these physical responses signals to your brain that you’re happy, causing your body to release more endorphins that further improve your mood.

#2: Your Body Language Influences How People Interpret Your Words

In addition to reflecting and influencing your emotions, another major reason why your body language is important, explain the authors, is because it influences the way others interpret your words. Allan and Barbara Pease explain that, during verbal interactions, people intuitively respond to each other based more on what they see than on what they hear. They suggest that your body language accounts for 60–80% of how others perceive you. This perception determines how they interpret and respond to your words.

(Shortform note: While it’s true that body language influences the way people perceive you, there’s no scientific evidence supporting the exact percentage breakdown the authors provide. Those who quote numbers on this subject are usually mischaracterizing mid-1960s research by Albert Mehrabian, who argued that 93% of communication is nonverbal—including body language and tone of voice—and only 7% is verbal. However, this formula was created for a specific context—to reduce uncertainty in understanding people who send mixed verbal and nonverbal signals. This implies that the more closely your words and body language align, the less attention others will pay to your nonverbal cues.)

The authors argue that people are more likely to respond positively to your words when they trust you, and the degree to which people trust you hinges on how well your words and your body language align:

When your body language aligns with your words, people trust you because they feel as though you’re expressing yourself honestly. For example, your partner trusts you when you tell her you love her because you look her in the eye and smile when you say it. As a result, she responds positively to your words by showing signs of affection—for instance, by relaxing her posture, smiling, and making eye contact.

When your body language doesn’t align with your words, people don’t trust you because they feel as though you’re lying or hiding something from them. For example, your partner doesn’t trust you when you tell her you love her because you avoid eye contact and clench your jaw when you say it. As a result, she responds negatively to your words by showing signs of withdrawal—for instance, by crossing her arms, turning away from you, and avoiding eye contact.

#3: Awareness of Body Language Improves Your Interactions

We’ve just explained a few reasons why body language is important, including how your body language has a powerful effect on both your emotions and the way others interpret and respond to your words. The authors argue that, since it plays an essential role in your interactions, awareness of body language is key to improving your communication skills. This is because it helps you consciously control both your emotions and the way others perceive you.

It Helps You Control Your Emotions

Allan and Barbara Pease argue that awareness of your body language is important because it helps you control your emotions during interactions. They explain that intentionally assuming different body language positions helps you experience more positive emotions.

Example: You feel nervous during a job interview and want to feel confident. You notice that you’re slumped in your chair with a frown on your face and your arms crossed. Because you understand how your body language influences your emotions, you intentionally adapt your physical presence to signal to your brain that you are confident. For instance, you sit up straight, relax your facial muscles, and unfold your arms. These changes create physiological responses in your body that make you feel more confident and also make you appear more confident to others.

It Helps You Control How Others Perceive You

Allan and Barbara Pease suggest that awareness of others’ body language is important because it helps you read their emotions. This in turn helps you control how they perceive you. In other words, knowing how to read other people’s emotions helps you adapt your approach to get what you want out of the interaction.

(Shortform note: Travis Bradberry and Jean Greaves (Emotional Intelligence 2.0) refer to the ability to read and respond to other people’s emotions as “social awareness.” In addition to understanding body language, the authors suggest that you can develop social awareness by listening attentively, learning the rules of your environment, practicing empathy, and focusing on the present moment.)

Example: You want your date to think that you’re interesting. However, you notice that she starts people-watching and tapping her foot every time you talk about your job. Because you know that these two cues indicate boredom, you switch topics until you find something that causes her to focus her attention back on you.

(Shortform note: The authors imply that you should attempt to influence others by adapting how you present yourself, based on your observations of their body language. Psychologists call this tactic of adapting your outward presentation impression management—and they’ve found that attempting to control interactions in this way often increases feelings of self-consciousness and social anxiety. This is because it forces you to pretend to be something you’re not—for example, by suppressing your emotions or feigning interest in things that bore you. So, while adapting the way you present yourself might improve the way others perceive you, there’s a chance it won’t make you feel good about yourself.)

Why Is Body Language Important? The 3 Key Reasons