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Why do we eat cake on birthdays?

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📓 The short answer

We eat cake on birthdays because the tradition is deeply rooted in Egyptian, Greek, Roman, and German history. The practice of celebrating birthdays with a cake became far more accessible to common people thanks to key innovations during the Industrial Revolution.

📚 The long answer

First, let's define a birthday cake.

There's a few key elements that make up a birthday cake, all of which have slightly different origins:

• The cake is for celebrating a special day.
• It has candles placed on top.
• It is made on annually recurring birthdays.

As it turns out, each of these birthday cake characteristics have historical ties, some dating back into ancient societies.

🥳 Who celebrated the first birthday?

The ancient Egyptians are credited with being the first to celebrate birthdays. Many scholars believe the first reference of a birthday celebration is found in the Bible's Book of Genesis:

But this wasn't any ordinary birthday — Egyptologists believe that this reference is about celebrating the Pharaoh's coronation day, or his "birth" day as a god. Definitely worthy of a birthday party!

These birthdays were most likely not celebrated annually. Not only are coronations of pharaohs more of a one-and-done type of event, but they likely didn't have the calendars in order to track a specific date over a year. While the Egyptians are credited with creating one of the first calendars, this Bible passage likely predates the first calendar.
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🕯️ Who started putting candles on cake?

The next time you're blowing out candles on your birthday cake, think of Artemis, the Greek goddess of the moon, the hunt, and childbirth.

Ancient Greeks would visit temples and light candles in order to pay tribute to the gods. In hopes of a safe pregnancy and childbirth, women would pay tribute to Artemis by making round honey and sesame seed cakes and lighting them with candles.

It's thought that the round cake and candles symbolized the moon and its light. In Greek Orthodox faith, smoke rising from a candle also symbolizes one's prayers rising to heaven.
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📅 Who first celebrated the birthdays of regular people with cake?

Ancient Romans are thought to be the first to celebrate the birthdays of ordinary, non-godlike people. Well, specifically, they put on birthday parties for Roman men who turned 50.

These quinquagenarians (yes, this is a real word) were celebrated amongst family and friends with a special cake baked with wheat flour, nuts, yeast, and honey.

Women's birthdays were not celebrated anywhere until about the 12th century (boo...).
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🎂 Where did a birthday cake lit with candles come from?

So from the Egyptians we got a Pharaoh's "birthday", from the Greeks we have lighting candles on cakes, and from the Romans the idea of celebrating birthdays of non-gods.

But the first ones to put all these elements together, giving us a birthday party with cake and candles, were the Germans with the celebration of Kinderfest ("child's festival").

In the 15th century, Germans believed that children were more susceptible to demons and evil spirits on their birthday. During Kinderfest, they would light candles for each year of the child's age, plus one as a wish for another year of good health, and place them on the cake.

Despite being presented with their birthday cake in the morning, these German kids would have to wait until after dinner to blow out the candles and chow down. Just like modern times, the child would make a wish before blowing out the candles.
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🏭 How did the birthday cake tradition become accessible to all?

For most of history, birthday cake (or any cake for that matter) was a delicacy reserved for wealthy people. The Industrial Revolution helped bring cake to the masses, with two important innovations: sugar production and baking powder.

Sugar: In 1843, Norbert Rillieux developed the Sugar Evaporation System. This process captured the steam produced from boiling cane juice to use it as a heat source to boil another batch of cane juice. The result was using far less energy to boil down cane juice into sugar crystals, lowering the cost of sugar.

Baking powder: In the 1800s, a British chemist named Alfred Bird had a problem. His wife Elizabeth was allergic to yeast, which was the primary leavening agent for bakers. Bird combined tartaric acid, cornstarch, and sodium bicarbonate to create baking powder. Using baking powder, bakers could make cakes that were higher, lighter, and faster to make than ones using yeast.

Thanks to these innovations with sugar and baking powder, the price of cake dropped so that more could enjoy their birthday with a candle-adorned cake.

Or in the case of Aberdeen, Washington (see below), the whole town got to enjoy the town's birthday with a 5-layer cake!

--- Thanks for reading this week's newsletter! If you have any thoughts, questions, or favorite GIFs, my inbox is always open. Just hit reply to send me a note! :) ​ All my best, Caitlin ​Click here to read five facts about Caitlin​

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​Sources for this week's newsletter​

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P.S. Because of an eye-opening video from Trevor Noah, my family has done away with the traditional birthday song. Instead we now sing our own version, inspired by Stevie Wonder's "Happy Birthday".

P.P.S. Happy early birthday to my love Saurav!

📖 Book of the week

​What If?: Serious Scientific Answers to Absurd Hypothetical Questions by Randall Munroe​

What if you tried to hit a baseball pitched at 90% the speed of light?

How fast can you hit a speed bump while driving and live?

What would happen if the moon went away?

The answers to all these wild questions make up this fascinating book. Randall Munroe (creator of xkcd) tackles these questions with the utmost sincerity with tons of scientific detail. It was such a fun read! I hope physics, biology, math, and chemistry teachers use these examples in their own classes.

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​Check out the full list of books I've recommended here.

👀 Catch up on other curious questions

• ​Why is the first pancake always bad?​​
• ​Why is a day 24 hours? Why is an hour 60 minutes?​​
• ​Why do candles smoke when blown out?​​

P.S. 🤔 Do you have a question for the newsletter? Click here to submit your question. (or reply to this email!)

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