Morning FJ
A cheaper alternative might be chromium. I take it every day and it's £3.69 from Holland and Barrett (recommended by Neris and India, who wrote a book detailing how they each lost 5 stone following a low carb eating plan).
Here's some info -
Chromium is an essential trace element needed in minute amounts to form an organic complex known as the Glucose Tolerance Factor (GTF). This interacts with the pancreatic hormone, insulin, to regulate the uptake of glucose by cells. GTF encourages the production of energy from glucose, especially in muscles, and may also suppress hunger pangs through a direct effect on the satiety centre in the brain.
Hope that helps.
Susie