Activist investor Bill Ackman may be busy on the M&A trail these days, but he hasn’t backed away from his real passion — trying to take down Herbalife, the nutritional supplements company he has bet $1 billion is a pyramid scheme.

Proving he’s still focused on the Los Angeles company, Ackman next week will unveil the results of an almost two-year probe by his Pershing Square hedge fund into Herbalife nutrition clubs, The Post has learned.

The findings, according to Ackman, will show how the nutrition clubs — owned and operated by Herbalife’s independent distributors — perpetuate the fraud.

Herbalife, which is under investigation by several regulators, has consistently maintained that it is not a pyramid scheme.

The hedge fund mogul, who has been busy in recent weeks helping Valeant Pharmaceuticals launch a $53 billion hostile takeover of botox maker Allergan, wouldn’t elaborate but a webcast of the probe’s finding is slated for 10 a.m. New York time on July 22.

Nutrition clubs were started in Mexico by Herbalife distributors as a way to introduce customers to the company’s shakes and other products and to recruit other distributors.

There are 3,000 nutrition clubs in the metropolitan New York area, an Herbalife executive told The Post. Dozens are clustered in the Corona neighborhood in Queens.

Ackman and other Herbalife critics have long said nutrition clubs are little more than recruitment venues, or what Ackman calls a “pyramid within a pyramid.”

Under a pyramid scheme, distributors’ profits come mostly from recruitment, not from selling products to customers. The scheme requires the constant addition of new distributors or it will collapse.

A new profile of a top Herbalife distributor posted Monday on Pershing Square’s Herbalife site seemed to reinforce Ackman’s allegation that the purpose of nutrition clubs is recruiting new distributors.

Herbalife executive president’s team member Brad Harris, a former hydraulic mechanic who runs several nutrition clubs, is quoted telling prospective recruits that, “People are going to see this and want to duplicate this and that’s when you start making royalties, which is the exciting part of our business.”

“We can actually build a distributorship by doing what we’re doing here,” Harris said, explaining the role of Herbalife weight-loss challenges that are done at nutrition clubs.