Weight Gain After Liposuction: Don't Do It!
I can tell you from personal experience, try as hard as you can to be diligent in maintaining a healthy lifestyle, diet and exercise regimen after liposuction.  Although you had fat cells removed during liposuction, your fat cells are designed to store the excess energy it consumes in the form of calories.  It's normal and expected in a healthy metabolism to do so.  You simply must expend more calories than you consume to lose (fat) weight, or consume equal ratios to maintain your weight. However, it will alter your surgical results.  Even if it is a couple of pounds, and it takes 3,500 excess calories to make one pound of fat, it has to go somewhere.  With slight weight (fat) gain, the area where you normally would show it is now unable to store your fat as it once did, where it was evenly spaced out.  Hence you may store the additional lipid content in the remaining cells in the treatment area which can create lumps or bumps.  You will also gain mass in the areas you normally wouldn't see as noticeably.   IN other words, areas that you would tend to see mass gain when you are 10 lb over your normal weight as opposed to 5 lb.  This means your arms, calves, breasts, buttocks, around the ribs, etc. 

I didn't gain significant weight, it was only a few pounds.  But the distribution was different within a year and a half after surgery.  I noticed my breasts had enlarged, as did my buttocks and the skin around the ribs.   I assure you I was not happy about this. I had spoken to a few of my friends who had experienced the same thing and they advised they had to watch their caloric intake more closely than before.  I realize age and hormonal fluctuations can change the distribution of fatty deposits.  But I noticed this within a year and a half.  My activity level did not change severely, nor did my caloric intake.  I feel I notice the fat gain in the other areas more than I would in the areas I was accustomed to all of my life.  

Hopefully, having had liposuction will trigger you to become more health-conscious and seek out an active lifestyle and better diet if you were sedentary and ate poorly before your procedure.  It is common that people start to take care of themselves more when they have new body to be proud of.   Just don't let extra calories ruin your liposuction results.