The Later You Wait To Spay Your Dog, The Less Likely She Is To Get Fat
So this gal did a study on a couple thousand dogs and figured out that if you wait a year, two years, several years, seven years to spay your dog, she’s less likely to get fat, the older she is. The problem obviously is that she is also open to diseases of the reproductive tract AND neoplasia in the breastline, AND you have to deal with bleeds every 6 months. But, I didn’t know this about age-of-spay.
In practice, I’ve seen no material difference in fattening based on spay before or after first heat. And frankly, if you feed modestly and appropriately, the dogs don’t have to get fat no matter what age they’re spayed.