Mannatech's New Management Team Poised for Future Growth.

Business Editors & Health/Medical Writers

BIOWIRE2K

COPPELL, Texas--(BW HealthWire)--June 16, 2000

Mannatech Inc. (Nasdaq:MTEX) today announced that Sam Caster, company co-founder, has been named Global Vision Architect.

"We are excited that Sam has agreed to continue on with Mannatech in this new capacity," said Robert Henry, Chief Executive Officer.

Caster's new role was made possible when Mannatech's board made the decision to add additional depth to the firm's management team as it begins an ambitious expansion program.

Mannatech develops proprietary nutritional supplements and topical products which it sells through a network marketing system throughout the United States and internationally.

Mannatech recently named Robert Henry to the post of chief executive officer and Terry Persinger as president. Henry's broad experience includes highly successful stints in senior positions at Avon and as Corporate Controller Worldwide for Amway.

Terry Persinger, responsible for day-to-day operations, joined Mannatech with 30 years of general management, operations, and research and development experience at the Goodyear Tire and Rubber Co. Persinger was vice president and general manager of Goodyear's Engineered Products Division. "Terry is uniquely qualified to see Mannatech through this challenging time of domestic growth and international expansion," Henry said. "This new arrangement will enable us to benefit from Sam's vast experience, keen insight and, most of all, his close relationships with our associates who make up the backbone of the company. Mannatech will remain a leader in the nutritional supplement industry," he added. Strong leadership is a hallmark of Mannatech, Henry noted. "Sam Caster set the leadership standard for the company's success. In just six years it grew from a grass roots idea to an international company with annual sales reaching $180 million. We look forward to an equally prosperous future."

Henry said Caster's new duties include:

-- Acting as corporate liaison to Mannatech's independent

Associates.

-- Assisting the management team in developing sales and

marketing devices.

-- Appearing at corporate-sponsored events to act as a

spokesperson as requested.

-- Assisting with Associate-sponsored events.

-- Promoting Mannatech in a positive manner.

-- Advising the management team as requested.

Caster noted that his new role will "take me out of all the day-to-day responsibilities and permit me to devote more of my energies to the two things I like best, my charitable activities with MannaRelief, and helping Mannatech grow."

The return of Mr. Caster to a Board position will be considered at the next scheduled meeting of the full Board of Directors, set for later in the summer. "It will be a pleasure to continue my relationship with our Associates and work with Bob and Terry. Mannatech's future is brighter than ever. Mannatech will be able to take full advantage of the strengths and experience Bob and Terry bring to their jobs," he added.

Caster co-founded Mannatech in 1993 with several scientific and financial partners. The company later developed the Ambrotose complex, Mannatech's proprietary blend of plant-derived carbohydrates that contain monosaccharides. These are known to play an important role in cell-to-cell communication, one of the most critical functions of the immune system of the body. Ambrotose is the foundation of Mannatech's nutritional products.

Caster's business experience and understanding of network marketing and the nutritional supplement industry enabled Mannatech to grow into a leading nutraceutical company. Mannatech sales exceeded ten million dollars a month after less than four years.

In May, the Dallas Morning News listed Mannatech as the 109th largest public company in the Dallas/Fort Worth area. Mannatech's 1999 revenues reached $180 million.

Some of the statements contained in this announcement may constitute "forward-looking statements" within the meaning of Securities Exchange Act of 1934 and that are subject to certain events, risks, and uncertainties that may be outside the control of the company. In some cases forward-looking statements may be identified by terminology such as "may," "could," "continuous," or the negative of such terms. Although we believe that the expectations and beliefs reflected in the forward-looking statements are reasonable, we cannot guarantee future events.