As mentioned in Part II, fat tissue expands by an increase (proliferation) of fat cells and/or a growth of the individual fat cells. This installment concerns the number of fat cells and is likely the least "actionable" in this series in terms of diet, unless you're planning to have a child and/or have young children. This does, however, lend some assistance to those formerly obese who are considering liposuction or more drastic surgery that may involve fat cell removal. Bottom line, the number of fat cells we have is virtually completely out of our control as adults (according to current understanding).
So this post will be rather short, and I plan to expand on the data we have regarding fat tissue development in infancy, puberty and other periods of childhood in subsequent installments. It would appear that the number of fat cells we are born with is determined somewhat later in gestation. At right is the progression of the formation of mature adipocytes. From this article: 
