
Hormone behind women having greater preference for sweets than men: Japan researchers
NARA -- A group of researchers at Nara Women's University in this west Japan city has discovered that estrogen, a female hormone, is responsible for boosting women's preference for sweet tastes through a rat experiment.
The group, led by professor Akira Takamata, points out that, "It is essential to consider gender differences in preventing lifestyle-related diseases such as obesity. For women, responses in accordance with changes in their hormonal environment due to menopause and estrous cycle are required."
It has been reported that female animals, including humans, tend to have a greater preference for the taste of sweet things than males, but it was previously unknown whether a sex hormone was the cause of this.
In the experiment, a group of rats that lacked endogenous estrogen after ovary removal and another group of the animal supplemented with estrogen were compared. Researchers allowed both groups to freely ingest water, fodder, calorie-free artificial sweetener and a calorie-rich sugar solution, and measured their intake. It turned out that the second group ingested large quantities of artificial sweetener and sugar water while not eating much fodder.
Estrogen is mainly secreted by the ovary and plays a significant role in the growth and maintenance of reproductive organs. Estrogen secretion increases from puberty and varies with a woman's sexual cycle. It reaches a peak in one's 20s and 30s and plunges during menopause.
The next challenge is to elucidate the mechanism of how estrogen increases the preference for sweetness.
The latest research also revealed the possibility that endogenous opioid, a morphine-like substance in the brain, may have to do with the preference for sweetness. Specifically, when the workings of opioid were halted by administering drugs, the subjects' preference for sweetness also disappeared. It is likely that the mechanism of a brain reward system is working here, according to researchers.
The findings were published in the European Journal of Pharmacology, with Natsumi Kosugi, a graduate student at the university, credited as lead author.
(Japanese original by Yasuhiro Okawa, Nara Bureau)
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3 hours ago
Japan's Economic Security and Strategic Technology Policy: An Interview with METI's Nishikawa Kazumi
Japan enacted its first law dedicated to economic security in 2022 amid escalating tensions between the United States and China. As the two superpowers vie for technological supremacy, Japan finds itself navigating a growing field of complex threats, including access to key materials and the global race for artificial intelligence dominance. In an exclusive interview. Nishikawa Kazumi of the Ministry of Economy, Trade, and Industry's Trade and Economic Security Bureau talks about Japan's strategic response to mounting pressures to its industrial and critical technology sectors. Senior Director of Ministry of Economy, Trade, and Industry's Trade and Economic Security Bureau. Born in Osaka Prefecture in 1973. Graduated from the University of Tokyo and joined METI (then the Ministry of International Trade and Industry) in 1996. 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SoraNews24
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The Mainichi
14 hours ago
- The Mainichi
Hormone behind women having greater preference for sweets than men: Japan researchers
NARA -- A group of researchers at Nara Women's University in this west Japan city has discovered that estrogen, a female hormone, is responsible for boosting women's preference for sweet tastes through a rat experiment. The group, led by professor Akira Takamata, points out that, "It is essential to consider gender differences in preventing lifestyle-related diseases such as obesity. For women, responses in accordance with changes in their hormonal environment due to menopause and estrous cycle are required." It has been reported that female animals, including humans, tend to have a greater preference for the taste of sweet things than males, but it was previously unknown whether a sex hormone was the cause of this. In the experiment, a group of rats that lacked endogenous estrogen after ovary removal and another group of the animal supplemented with estrogen were compared. Researchers allowed both groups to freely ingest water, fodder, calorie-free artificial sweetener and a calorie-rich sugar solution, and measured their intake. It turned out that the second group ingested large quantities of artificial sweetener and sugar water while not eating much fodder. Estrogen is mainly secreted by the ovary and plays a significant role in the growth and maintenance of reproductive organs. Estrogen secretion increases from puberty and varies with a woman's sexual cycle. It reaches a peak in one's 20s and 30s and plunges during menopause. The next challenge is to elucidate the mechanism of how estrogen increases the preference for sweetness. The latest research also revealed the possibility that endogenous opioid, a morphine-like substance in the brain, may have to do with the preference for sweetness. Specifically, when the workings of opioid were halted by administering drugs, the subjects' preference for sweetness also disappeared. It is likely that the mechanism of a brain reward system is working here, according to researchers. The findings were published in the European Journal of Pharmacology, with Natsumi Kosugi, a graduate student at the university, credited as lead author. (Japanese original by Yasuhiro Okawa, Nara Bureau)