Why the Heart Appears on the Left and What It Reveals About the Body’s Design

Adi asks: "All living beings are symmetrical, so why isn’t the human heart positioned symmetrically in the body? Why is it not in the middle, but instead on the left side? God could have created it symmetrically."

* * *

Shalom and blessings Adi, and thank you for your interesting question.

The question you raise is based on a common misconception that I myself, like many others, once assumed to be true. The human heart is in fact located in the center of the body. The heart is made up of chambers, and the largest chamber is located toward the left side of the body, which is why it is commonly said that the heart is “on the left.” Anatomically speaking, however, the organ itself sits in the center of the chest.

A more precise question would be: Why did the Creator make the left ventricle larger than the right ventricle? Scientists have offered several explanations. According to Wikipedia: “The left ventricle is larger and thicker than the right ventricle because it pumps blood to the entire body, which requires a stronger mechanical contraction to push the blood with enough force to reach all areas.”

In a scientific article called “The Left Heart Gene” by biologist Steven Dickman (Galileo magazine, issue 21, March/April 1997), he explains: “The asymmetry between the two halves of the heart is also reflected in their structure in that the left side is more muscular than the right. Internal asymmetry exists in other organs as well, sometimes to save body volume. For example, the left lung has fewer lobes to make space for the heart, and the shape of the liver matches the curve of the stomach. Overall, our asymmetry helps us survive.”

The asymmetry of the heart and other organs is necessary for the body’s optimal functioning. God created us externally symmetrical and aesthetically balanced, but internally designed us for maximum efficiency.

The article further explains that some researchers trace the larger left ventricle to the heart’s development in the womb. Even if there’s no inherent superiority of the left side over the right, the difference in size is crucial for arranging the organs in the chest and ensuring efficient function. Perhaps in the future, science will uncover the exact reason the left side was chosen.

Nothing in creation is without reason, as King David beautifully said: “How great are Your works, Hashem, in wisdom You have made them all” (Psalms 104:24).