Very short-term fluctuations in weight are usually caused by retention and flushing of water. Gaining 30kg over the course of 20 years is not water weight. If y

Very short-term fluctuations in weight are usually caused by retention and flushing of water. Gaining 30kg over the course of 20 years is not water weight. If you were retaining that much water, you'd be so arthritic feeling I'm not sure you'd able to stand up. Unless you've been very serious and consistent about weight training that entire time, that 30kg is virtually all fat.