(Bloomberg)—Carlyle Group LP is exploring a sale of nutritional-supplements maker Nature’s Bounty Co., whose brands include “MET-Rx” and “Pure Protein,” people with knowledge of the matter said.

The private equity firm has held talks with potential advisers about selling the U.S. company, formerly known as NBTY Inc., according to the people. Nature’s Bounty, No. 174 in the Internet Retailer 2016 Top 500 Guide, could fetch as much as $6 billion in a sale, the people said, asking not to be identified because the information is private. The retailer had $186.7 million in 2015 web sales and a five-year compound annual growth rate of 8.45%, according to Top500Guide.com data.

While finding a buyer for the whole business is the preferred option, Carlyle also may decide to shop the international division separately, two of the people said. Holland & Barrett, based in the U.K. and founded in 1870, is the leading retailer of vitamins, minerals and herbal supplements in Europe, according to Nature’s Bounty’s website.

Holland & Barrett would likely draw interest from Asian suitors as the brand is well-known in China, where it sells its products on Alibaba Group Holding Ltd.’s popular Tmall e-commerce site, one person said.

Nature’s Bounty, led by President and CEO Steve Cahillane, generated about $3 billion in revenue last year, according to the people. A spokesman for Washington-based Carlyle declined to comment.

Carlyle agreed to buy Ronkonkoma, N.Y.-based NBTY in September 2010 in a take-private transaction valued at about $3.8 billion. The firm used capital from two of its pools, Carlyle Partners V, the global buyout fund it raised in 2007, and Carlyle Europe Partners III, which was raised in 2006.

David Rubenstein, Carlyle’s co-founder, said in October the private equity firm plans to embark on a global fundraising tour to replenish its coffers with $100 billion over four years.