* Co to make changes to clarify wholesale customers, distributors
* To provide more info on average compensation
* Investor Ackman says his questions still unanswered
Feb 20 (Reuters) - Herbalife Ltd said it will more clearly identify different types of customers, responding to criticism from investors including hedge fund manager William Ackman, and added it has held "short" discussions with billionaire investor Carl Icahn.
The diet supplements company, which sells products through a network of independent distributors, has come under intense scrutiny from Pershing Square Capital Management's Ackman, who revealed a short position in the stock in December and called the business "a pyramid scheme".
On a post-earnings conference call with analysts on Wednesday, Herbalife said it will more clearly identify the wholesale customers among its 3.2 million distributors from April.
The company's use of the word "distributor", and what payments they receive from the company, has been central to the debate over its business model.
Herbalife also posted on its website updated and expanded statements of average compensation that will also be included in every new distributor application in the United States by the end of February.
"This document sets a new disclosure standard for compensation in the multi-level-marketing industry," Chief Executive Michael Johnson said.
However, Ackman appeared unsatisfied with the changes.
"If Herbalife really wants investors to understand their business better and provide full transparency as (CEO) Johnson said on the call, they should start by answering even one of the 284 questions we submitted publicly to them two weeks ago," the investor said in an emailed response.
Shares of Herbalife, which raised its full-year earnings forecast on Tuesday, closed down 5 percent at $37.78 on the New York Stock Exchange on Wednesday.
Ackman's arguments include assertions that Herbalife's disclosure on average compensation is "materially deceptive" and that the company's distributors "experience an abnormally high failure rate".
Herbalife said earlier this month that on average, 73 percent of its "distributors" join Herbalife just to get a discount on the products rather than to earn money.
The company said 88 percent of its distributors received no payments in 2012, including 71 percent who did not recruit any other distributors. The rest of them potentially recruited other distributors but did not make money because the recruits did not sell enough products.
Herbalife said on Wednesday it has had short discussions with Icahn, who last week revealed a 13 percent stake in the company and offered to help the company explore options, including a recapitalization and a going-private transaction.
Icahn and another hedge fund manager, Third Point's Daniel Loeb, have defended the company against Ackman's allegations.
"Yes, we've had short discussions with Icahn. Beyond that, there's nothing concrete to report," said CEO Johnson in reply to an analyst's question on the earnings call.
Icahn has declined to say whether his firm, Icahn Enterprises LP, would launch a tender offer for shares of the weight-loss products company but said last week that financing a takeover would not be a problem.