They Are Open-Minded
Open-minded people are those who are open to new ideas and to changing their minds if they are wrong. This is not only a sign of emotional maturity but also of a higher IQ because smart people are always receptive to learning more.
Learning more means being challenged, embracing new ideas, and admitting when you're wrong. Smarter people also tend to listen to both sides of an argument and make a calculated opinion afterward.
They Are Modest
As a rule, smarter people tend to be more modest than those with a lower IQ. This is because smart people are very self aware and know the extent of their abilities, so they know what they can and can't do and are OK with it.
Meanwhile, less smart people tend to pump themselves up and present themselves in an overly-confident manner to compensate for what they are lacking. This phenomenon is known as the Dunning-kruger effect.
They Were Breastfed
While baby formula is much better today than it was decades ago, many people believe that the best option for babies is the natural route. According to several studies, those who were breastfed as babies have a higher IQ than those who weren't.
in fact, they tend to have around six IQ points more, which is a lot. Don't feel bad if you can't breastfeed your children though, not everyone has the opportunity to do so, and your kids will be just fine without it.