DIET AND IQ

I assume that poor families have poor diets from birth and wonder if this can account for such babies to develop lower IQs?  The main growth stage of the brain occurs in the first three years.

An article in the Telegraph on October 21, 2019, finds that diet in early childhood can influence intelligence to some degree.
The results found after taking account of potentially influential factors, a predominantly processed food diet at the age of three was associated with a lower IQ at the age of eight and a half, irrespective of whether the diet improved after that age.
.................................................................
She noted the brain grows at its fastest rate during the first three years of life – indicating that head growth at this time is linked to intellectual ability.*

There are other articles claiming diet in the earliest years can raise your IQ

All types of oily fish apart from canned tuna, are an excellent source of

the omega-3 fats which play important structural and biochemical roles in the

brain.

Lack of the fatty acid DHA in the womb can hinder brain development, and

premature babies given non-fortified formula milks develop lower IQs than

those fed breast milk naturally rich in omega-3s.**

*https://www.telegraph.co.uk/news/health/news/8308726/Food-for-thought-diet-does-boost-your-intelligence.html
** https://www.dailymail.co.uk/health/article-3002/The-IQ-diet.html