Gaby
The largest study yet on the topic found that people conceived in colder months store fat differently than those conceived in warmer months.
A team from the University of Tokyo, led by biomedical researcher Takeshi Yoneshiro, recruited 356 healthy young men for the study. The researchers found that those conceived during the cold season exhibited higher activity levels of brown adipose tissue.
Brown adipose tissue is a type of fat that burns energy, retains heat, and helps regulate blood sugar levels.
Together, those traits suggest better metabolic health, as reported by Science Alert.
People with overweight or obesity often have reduced brown fat activity.
What Else Did the Scientists Discover?
To test whether the findings held in a larger group, the team examined a second cohort of 286 adults. They found modest but significant links between conception during the cold season and higher brown fat activity, and between cold-season conception and lower BMI, smaller visceral fat area, and reduced waist circumference.
The researchers believe that increased activity of brown adipose tissue (BAT) drives other metabolic processes.
The study suggested that cold weather might alter gene expression in sperm or eggs, and that those changes could be passed to offspring at fertilization.
The authors suggest this could be a ‘complex adaptive response to cold’ passed down through generations, giving descendants a better chance of surviving in cold climates.
The findings echo earlier observations that the season of birth can affect health later in life.
The study results were published in the journal Nature Metabolism.
