Back to today’s briefing

Story perspectives

Debunking Myths: Heat Loss Isn't Just Head-Related

1/19/2026

38 5

Summary

Story summary

The 1970s US Army Survival Manual states that 40-45% of body heat is lost through an unprotected head.
John Tregoning, a vaccine immunology professor at Imperial College London, disputes this, saying heat loss occurs from any exposed area, not just the head.
He cites a 2008 BMJ article noting the head is less insulated due to less fat and concludes the head is not uniquely vulnerable.

1 of 1

Story summary

The 1970s US Army Survival Manual states that 40-45% of body heat is lost through an unprotected head.
John Tregoning, a vaccine immunology professor at Imperial College London, disputes this, saying heat loss occurs from any exposed area, not just the head.
He cites a 2008 BMJ article noting the head is less insulated due to less fat and concludes the head is not uniquely vulnerable.