Babies Conceived in Winter May Have Lower Obesity Risk as Adults, Japanese Study Shows
According to research conducted by a team from a Japanese university, individuals conceived during the winter months have a lower likelihood of becoming overweight as adults. These insights could potentially pave the way for novel approaches to combating obesity and related health issues.
The research group led by Tohoku University studied two kinds of body fat—white fat, which acts as an energy storage, and brown fat, which generates heat through energy consumption—in their investigation detailed in the Nature Metabolism journal on Tuesday, as reported by The Japan Times newspaper.
As body temperatures drop, brown fat triggers the body to consume fat. Consequently, people with higher levels of active brown fat may find it simpler to maintain a lower weight.
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In their research, the scientists examined the brown adipose tissue of 356 Japanese males aged from 18 to 29 years old, with participants grouped according to the month during which they were conceived.
The study revealed that brown fat exhibited higher activity levels in males born between October 17 and April 15—during the cooler months—compared to those born during the warmer periods.
The researchers also examined the locations of the men’s mothers during their pregnancy and observed the prevailing weather conditions. They found that increased levels of brown fat activity correlated with colder exterior temperatures prior to conception as well as greater variations in daily temperature.
In the course of this research, the group also studied 286 individuals, both men and women aged from 20 to 78 years old.
The evaluation of this group also revealed outcomes comparable to those of the men's group, indicating a connection between increased brown fat activity during colder periods and reduced body mass index scores.
Takeshi Yoneshiro, an associate professor at Tohoku University and the lead researcher of the study, mentioned that these discoveries could be beneficial for preventing obesity.
He stated: "It seems to be an adaptive mechanism for surviving in frigid regions."
Based on the team's hypothesis, the research indicated that "conceiving during colder months might decrease the likelihood of offspring developing obesity and metabolic disorders by safeguarding them from the natural reduction in brown fat as they age."
The team, nevertheless, recognized the constraints of the research, considering it was centered on Japan .
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