In 1989, Dr. Beverly Whipple and a team of researchers set up a human subjects laboratory at the University of Veracruz in Jalapa, Mexico. Twenty-five women who were born, raised, and living in Central Mexico were the subjects of the test. The women did not know why they were being tested, and the test was never fully finished.
The findings, while not conclusive, were fascinating . . . and are about to be revisited.
Dr. Whipple—a renowned sexuality counselor, certified sexuality educator, and sex researcher perhaps most famous forpopularizing the G-spot—was no stranger to controversial studies. She and sex therapist Gina Ogden had just published the book Safe Encounters: How Women Can Say Yes To Pleasure and No To Unsafe Sex, addressing what women could do to protect themselves from AIDS and still foster a robust sex life.
This time, Whipple and her team were seeking to better understand the relationship between pain perception and vaginal stimulation. A study she conducted with Dr. Barry Komisaruk had already revealed a link between vaginal self-stimulation and rising pain thresholds; orgasm, it seemed, made overall physical pain less painful.
The study in Mexico aimed to look at how capsaicin, a chemical found in chili peppers, affected those thresholds.
In previous studies, Whipple discovered that rats exposed to the capsaicin experienced no pain-relieving side effects despite their vaginal stimulation. It seemed that chili pepper consumption rendered the orgasm-induced pain reducer null and void.
“I was intrigued with the study in rats,” explained Whipple in a phone interview, “and I wondered if the same thing happened in women with a diet high in hot chili peppers, and if maybe that is why the Spanish-speaking women in my area in New Jersey had a harder time during labor.” Through international anecdotal reports she noted a compelling, if troubling, trend.
In Kuala Lampur, for example, Whipple spoke to a few hundred OBGYN doctors, all of whom supported her initial theory:
“They have three different ethnic groups in Malaysia: Chinese, Indian, and Malays. I asked them here in Malaysia, ‘Is there any group of women who have a harder time during labor?’ And they all said women of Indian descent have a harder time.”
These are speculative reports, but with a logical conclusion: the Indian women had a more difficult time with childbirth because they were consuming diets high in capsaicin.
Capsaicin, it seemed, worked to block certain pain receptors associated with the G-spot (aka The Dr. Gräfenberg Spot)—the sensitive area in the front (anterior) of the vaginal wall. Whipple had published a lengthy study in 1981 featuring the responses of 400 women to stimulation, which basically put the G-spot on the map. Whipple was wondering if this elusive vaginal area “had an adaptive significance,” she explained.
The G-spot, when stimulated, supposedly raises pain thresholds. Interestingly enough, during childbirth, the G-spot is directly and almost aggressively stimulated by the enormity of the baby passing over it; this intense pressure is believed to be an adaptive mechanism that makes childbirth just a bit more bearable. And this increase of pain tolerance was the very thing capsaicin was apparently blocking.
Getting a team down to Jalapa, Mexico to prove this hypothesis, however, took a fair share of hoop-jumping.
In the early 1970s, Dr. Whipple was teaching nursing in New Jersey when one of her students asked her a question she couldn’t answer. “What can a man do sexually after a heart attack?” She knew just one guideline at the time—he could go back to sexual activity once he was able to climb two flights of stairs without losing his breath. She talked to other nursing faculty in the program and discovered that none of them knew anything about the relationship between sexuality and heart attacks, either. So they decided to invite a marriage counseling specialist from Philadelphia to come and speak at the school, in the hopes of incorporating sexuality into the nursing curriculum.
“We had to go to the board of trustees and they said, ‘No, you can’t implement this curriculum because you will be talking about’—listen to the word I say—‘masturbution and all those awful things.’ Masturbution.” And just like that, Whipple recognized that this was not the place for her.
So she quit her job, taught at another college, and took master’s classes every summer with the American Association Of Sex Educators, Counselors and Therapists. She went on to serve as acting president of that association from 1998-2000, and later took on executive roles with the World Association for Sexology, the World Association for Sexual Health, and the Society for The Scientific Study of Sexuality.
Eventually, Whipple was teaching Kegel exercises and pelvic wall strengthening exercises to both her hospital patients and medical students, not for the sexuality element, but as part of being a nurse, aimed at helping women to help themselves. The exercises were meant to prevent surgery for urinary stress incontinence. “Arnold Kegel, who developed these muscle exercises, reported that he taught them to women using a biofeedback device that he developed—which I think was the first one,” recalled Whipple. “It was like a little rubber sleeve that you squeeze and you get a reading like a blood pressure cuff of the strength of your pelvic floor muscles.” Biofeedback like this would come in handy later when she began doing her own research.
“That was the beginning of my validating sexual and sensual experiences reported by women that the books said didn’t happen. Such as the women who had orgasm from imagery alone—just thinking.” While working on Safe Encounters, her co-author Ogden had explained her doctoral dissertation on “50 easily orgasmic women.” “Of those 50,” Whipple said, “64% could orgasm just by thinking—with no one touching their body, including the women themselves.”
In response to new sexual data, she and Ogden mapped what they termed “the extra genital matrix” to help people map their body and discover other areas where they could derive physical or imagined imagery of sensual and sexual pleasure. What followed was a full-blown study on women who had orgasm from imagery alone.
“I had them use genital self-stimulation and imagery in a counterbalanced way, and found there was no difference in their physiological and perceptual measurements, including blood pressure, heart rate, pain detection threshold, pain tolerance threshold, or the pupil diameter of their eye. When they had orgasm I had them sit up with their chin in a chin bar and had them measure the diameter of their pupil—there was no difference in the orgasm response.”
Meanwhile, as she was helping women with urinary stress incontinence, she stumbled across the obscure study by German gynecologist Ernst Gräfenberg; the paper explored what was later termed “female ejaculation. ” Whipple’s brought attention to the buried research and renamed the “squirt”-inducing area the “G-spot.”
Which brought her to the chili pepper. She returned again to her hypothesis—did a diet high in capsaicin make childbirth more painful?
In a questionnaire delivered during the 1989 Mexico study, each subject during was interviewed concerning her diet—just how much chili had she consumed since childhood. According to the account of this research, there were three species of chili identified by the subjects; Capsaicin consumption was organized into three groups: low, medium, and high. Low meant the subject had a long-term diet that included only one chili pepper per week; high meant the subject consumed chili peppers three times a day.
Much like other tests of this kind facilitated in the U.S., an Italian pain-measuring machine called a Ugo Basile “analgesia meter” was used. The machine worked by applying a steadily increasing force to a fingertip. Once the subject felt the force, they said “now.” This was their “pain detection threshold.” When the force became unbearable, too uncomfortable to continue, they said “stop.” This was their “pain tolerance threshold.”
Dr. Pablo Pacheco of Veracruz, Mexico, who was part of this study, cited in a phone interview the complicated factors that come into play when attempting to calculate and measure human pain, including education, financial disparities, and cultural differences. To combat these complications, other methods of measuring pain thresholds were used, including the application of a fur mitt to the face to test tactile sensation and Von Frey Fibers, a series of fibrous strands with different levels of stiffness, that are pressed against the skin’s surface. All these different applications are designed to elicit different levels of pain measurement.
The women were asked to stimulate themselves vaginally using a sterilized cylinder with a condom over it. They were then asked to apply pressure inside of their vaginas. While they were self-stimulating, their pain thresholds were also being measured.
The test discovered a marked difference in the alteration of pain thresholds during manual vaginal self-stimulation in women with diets high in capsaicin. They found that women with a diet low in hot chili peppers experienced a 32.6-43.8% raise in pain detection and pain tolerance thresholds, whereas women with a diet high in hot chili peppers only experienced a 2.3-7.3% increase in pain thresholds.
In short, they discovered Whipple’s hypothesis was proving to be correct; the pain-reducing effects of vaginal stimulation were vastly lower among women who had consumed a diet high in hot chili peppers.
(In regards to what steps women should take during pregnancy, or whether there is a permanent effect on the bodies of women who consumed high percentages of chili pepper daily, the study was non-conclusive.)
But fret not. Dr, Whipple has plans to replicate the study to find more conclusive results; funds are currently being sought to complete the research so the data can be made scientifically available.
“We have to listen to what people say is pleasurable to them so we can proceed to investigate this in a laboratory setting,” she said. “This work is meant to help people feel good about themselves, to accept themselves, and not try to fit people in the model of only one way to respond sensually and sexually. There is so much more we still don’t know.”