The toddler testosterone surge – fact or myth?

Posted on July 5th, 2019

Have you ever been told as you try and calm down your grumpy four-year-old that it’s just because he’s a boy? We debunk the myth of the toddler testosterone surge. By Kim Bell

Toddler testosterone surge

Yes, toddlers and preschoolers can go through their challenging stages and ages – but this doesn’t seem to differentiate much between boys and girls.

The thought that boys have a testosterone surge at the age of four has garnered support over the years, since it first came to light in Steve Biddulph’s best-seller, Raising Boys, back in the 90s. Steve, a psychologist and author, was, in fact, quoting Professor Michell Harman from the US Department of Aging, who said boys undergo a testosterone spurt at the age of four in an article he wrote for Esquire in 1999. However, said Biddulphs, not all researchers have agreed with this finding, which to this day remains controversial.

So is there any truth to the toddler testosterone surge theory?

Biddulphs was quoted as saying in 2018 that as Professor Harman is a world authority on male development, he felt comfortable with quoting him in earlier editions of his book. However, these findings have been questioned by the experts, and further editions published after 2008 do reference this. Biddulph says that there is a rise in the Luteinizing hormone at age four, which creates the testosterone-making cells ready for puberty.

According to Kate Steinbeck, Medical Foundation Chair in Adolescent Medicine, University of Sydney, in her article Health Check: Do boys really have a testosterone spurt at age four? “As a researcher and adolescent endocrinologist, who specialises in puberty hormones, I can say there is no evidence this testosterone spurt exists.”

There are hormone changes that take place starting at the age of five or six, but this is known as adrenarche, which occurs in both boys and girls. “Adrenarche is the maturation of the part of the adrenal glands where hormones similar to, but much weaker than, testosterone are made.” However, this hormonal change has more to do with body odour changes and less with behavior issues. As Steinbeck adds: “Researchers don’t know why exactly boys and girls have this phase. And no one has seen any clear effects on childhood behavior yet.”

ALSO SEE: 6 tips to deal with your toddler’s cheeky behaviour 

Explaining the challenging behaviour

She explains this age is the time children learn how to interact socially with each other. Children must learn to regulate their own emotions, like fear, concern, upset and anger, Steinbeck explains. “When children don’t do this, we see the emotional outburst, which can be explosive.” Boys tend to respond more physically and be less able to articulate why they have lost control of their emotions.

Professor David Segal, a Johannesburg-based paediatric endocrinologist and diabetologist, and founder of Dr David Segal Inc (endo.co.za) explains that typically boys don’t show signs of puberty before nine years of age and girls before eight years of age. However, there may be precocious (early) puberty, that occurs before this. “In boys the first sign of puberty is the enlargement of the testes – a sign very rarely detected by parents. Early pubic hair development or body odour are worrying symptoms and signs and need further investigation”.

Kim Bell

About Kim Bell

Kim Bell is a wife, mother of two teenagers and a lover of research and the way words flow and meld together. She has been in the media industry for over 20 years, and yet still learns more about life from her children everyday. You can learn more about Kim Bell here.