"Emotional support networks among men shrink by 50% between the ages of 30 and 90, reflecting an average decrease from two to one emotional support providers"
Or, to rephrase,
"Men grow up with an average of two emotional support providers and lose one in mid to late adulthood"
Or, to rephrase,
"Men grow up with an average of two emotional support providers and lose one in mid to late adulthood"