The £150,000 (€221,000) deal is expected to come into effect on 13 September.
Skinny Candy Ltd. and Glisen will set up a equaly shared joint venture to run the brand and the expanded portfolio.
This deal forms part of Glisten's strategy to build on the demand for low fat and low calorie foods, a market that is currently showing strong growth worldwide.
"Consumers still want great tasting chocolate and sweet treats but a rising number of people now insist on some additional functional benefits and ideally some element of guilt-free self-indulgence," said Glisten's chief executive Paul Simmonds.
"We feel that Skinny Candy is an exciting brand with a fantastic young image and real consumer relevance, which will allow us to capitalise on the well-being trend."
Skinny Candy was founded in 2005 by Sahar Hashemi, the co-founder of the Coffee Republic chain.
The brand focuses on the low sugar and low fat confectionery market, and the companies hope the venture will help to build upon the portfolio, targeting young consumers.
"Our job now is to build the brand, market and sell it across Glisten's full spectrum of customers, and create even better 'Skinny' products from within Glisten's manufacturing network," Simmonds added.
According to a Letherhead Foods study in June, the overall market for "low and light" products in the US, UK, Germany, Italy, France, Spain and Australia was worth a total of €49bn last year.
The report said UK consumers spent the most on these foods per capita, throwing €122 per person at these foods, compared to American spending of €93, and €86 in Australia.
A Packaged Facts study revealed healthier variations of non-chocolate candy are driving the growth in the confectionery Markey, particularly with organic and fortified candy.
Glisten manufactures organic and natural snacks and premium confectionery within the UK and to over 20 countries worldwide.
The company has two nut-free and two organic-accredited factories in the UK.
Turnover for the year ended 30 June 2007 was £58.6m (€86.3m), Glisten added.