Research Says Your Younger Sister Could Be Making You Fat

Surprising new research has just found that having a younger sister makes it more likely that you will be fat.

Researchers looked at 13,406 pairs of Swedish sisters that were born between 1991-2009, and they found that the sisters who were born first had a greater body mass index (BMI). In addition, the researchers concluded that it was more likely that they would be obese or at least overweight.

Though they found that older sisters tended to be lighter than their younger sisters at birth, they ended up with a 2.4% higher BMI when they got older.


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They found that 29% of firstborn children are more likely to be overweight in comparison with the younger sibling, and that older ones had a 40% greater likelihood that they would be obese.

There have been many theories as to why older sisters tend to be fatter than their younger siblings. Prof. Wayne Cutfield from the Liggins Institute at the University of Auckland said that one reason could be that during the first pregnancy, the blood vessels that supply nutrients to the fetus are thinner. This means that older siblings get fewer nutrients so they are more likely to store fat and have problems with their insulin.

Another theory comes from Dr. Maria Peña, Director of the Center for Weight Management at Lenox Hill Hospital in New York City, who said that it is more likely for a mother to overfeed the first baby so that they are a healthy weight. This overfeeding can then continue when the baby grows up.


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u can tell my mom for sure made us take this pic .. those fake ass smiles lol

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A third theory is sibling rivalry.

“Maybe the first-born competes with the second-born for food in the household. Maybe more money gets spent on the firstborn,” said Gary Sacks of Deakin University in Melbourne, Australia.

Do you think this rings true? Let us know in the comments section.


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