A 1930s eugenics experiment is the reason women's clothing sizes are so damn frustrating

• In her book, "Butts, a Backstory," Heather Radke revealed how women's sizes came to be.
• Measuring squads visited American households and only maintained white women's measurements.

A 1930s eugenics experiment is the reason women's clothing sizes are incredibly frustrating, according to author Heather Radke, who wrote a book exploring the feelings women have with one particular body part — their butts.

In her book, "Butts, a Backstory," a book about our complicated relationship with our backsides, Radke revealed the history of eugenicists' obsession with "what a good body is" and how their methods influenced women's clothing sizes.

Hint: It has to do with racism.

During her reporting, Radke stumbled across the reason why clothes don't fit and where ideas about the "normal" American body originated: two statues created in the 1940s by gynecologist Robert Latou Dickinson and artist Abram Belskie — and a government employee's quest to create sizing for women.

In an email to Insider, Radke said the discovery about women's clothing sizes was one of the biggest surprises to her when researching "Butts, a Backstory."

"I had always felt like there was something wrong with my body because I often couldn't find clothes that fit me well, but when I learned about the history of sizing and the way sizing works today, I realized that clothes actually aren't designed to fit. They can't be," she said. "There are just too many variables in the human body for clothes to fit most people well."

The life-sized plaster casts made by Dickinson and Belskie were dubbed Normman and Norma and helped create standardized clothing sizes. According to Radke, their purpose was to depict what a normal American body should look like.

Sculpting the perfectly normal man was easy: Men were required to have their measurements taken when they joined the army, therefore tons of data existed from both World War I and II.

As per Radke's book, to create Norma, Dickinson and Belskie needed to find more information on how women were shaped. As the workforce expanded and catalog shopping become popular, retailers wanted to capitalize on this new consumerism but there were limitations due to the lack of sizing available for women. In many instances, women were sending items back because they didn't fit. Many American women either made their own clothes or hired others to do so because of the dearth of sizing. Sears may have been the Amazon of its time, but it didn't come with the ease of making returns.

In the 1930s, Ruth O'Brien, who worked at the Bureau of Home Economics and was the first head of the Textiles and Clothing Division — a US Department of Agriculture department that studied the best ways to clean, sew, and purchase food and clothing — wanted to tackle this problem facing half of the population.

O'Brien worked on the development of standard sizes for commercially-sold clothing and fabric selection for the home sewer. It's not clear whether the government was working with clothing manufacturers but part of O'Brien's job was to negotiate with manufacturers, retailers, and other government agencies. To help her, the Works Progress Administration — a New Deal agency established during the Great Depression by President Franklin D. Roosevelt — recruited women for "measuring squads" that visited American households and recorded women's measurements.

Non-white women's data erased

In the book, Radke revealed that O'Brien advised the measuring squads to take the measurements of all women, but O'Brien said non-white women would have their data erased. This included Black, Italian, Eastern European, and Jewish women, Radke said, who were not considered white.

"In the case of Norma, the minds that collated her measurements were enthusiastic eugenicists, motivated by a desire to effectively eradicate insufficiently white, disabled, and queer people," Radke writes in her book: "They were openly attempting to engineer a race of perfectly normal Americans, equating full citizenship with having this decisively average, yet demonstrably unattainable, body. By codifying normal, the Norma boosters were also codifying abnormal, which is always the implicit project of the creation of an ideal."

While Radke couldn't confirm O'Brien's reasoning, in a November "Radiolab" interview about her book, she hypothesized that it could be O'Brien believed that by including non-white women's sizes, whatever clothes were then made wouldn't fit white women.

O'Brien created 27 sizes from her measurements, a number Radke said was prohibitively expensive. The garment industry, which was rapidly growing at the time, took those sizes and turned them into a version of the sizing we have now.

"Although the data [O'Brien] collected was used for women's sizes throughout the 20th century, her story shows us both how difficult it is to create a standard sizing system for women's clothes, and how ingrained racism and eugenics were in American life in the 1930s and '40s," Radke told Insider.

'She's the new Norma'

Dickinson and Belskie discovered O'Brien's data and were able to create Norma and Normman, the statues that were displayed at the American Museum of Natural History in New York in 1943. The statues were carved of white alabaster and based on the measurements of 15,000 men and women between the ages of 21 and 25 taken from the military and the measuring squads.

In an excerpt from Time Magazine in June 1945, Norma was described as showcasing the evolution of the US female figure toward a taller, lustier type of body. During the "Radiolab" interview, Radke said that at the time, ideas about what was "normal" were appealing and people craved a return to that normalcy, which created an emphasis on how bodies should look — especially after the uncertainty during World War II.

During the 1950s, standardized clothing sizes were adopted by clothing brands. Over time, these brands began to use fit models to perfect the fit and drape of the garments. One fit model in particular, Radke said, has become the blueprint for sizing.

"She's the new Norma," Radke said in the interview, referring to a fit model named Natasha Wagner, a white, relatively thin woman, "whose butt is the butt that jeans companies use to make the jeans fit." According to Radke, Wagner's butt measurements are used by about eight clothing companies. "She's the only person they [clothes] fit unless you have her exact body and her exact measurements," Radke said.

The takeaway, the author told Insider, is that it's important to realize that, often, clothes aren't meant to fit.

"It's just too expensive for garment manufacturers to make enough clothing sizes to accommodate the wide variation of human bodies. This can be profound because it can help to feel less like something is wrong with your body when you can't find clothes that fit," she said.

"It isn't your body that is wrong," she said. "It's the clothes."