We hold ourselves to a higher standard
Our Story
Our Mission
Our mission is to provide those in need with the highest quality supplements to support healthy lifestyles and provide digestive results you can feel!
Our Values
Higher Standards:
We strive to raise the standard in every aspect of our business, from how we treat our employees and customers, to how we develop and formulate our products.
Honesty:
We are committed to full transparency to help our customers make informed decisions for themselves and their families.
Hard Work:
We believe in rolling up our sleeves and doing what it takes to get the job done, and doing so with excellence.
Helping People:
Our products genuinely help people, so we come to work knowing that we make a positive difference in our customers' lives.
Our First Probiotic
In 2003, Randolph S. Porubcan created the formula for Theralac®, Master Supplements’ first probiotic. It led the way in so many vital areas that have become cornerstones to many quality probiotics available today. Randy, a microbiologist, relied on over 40 years of experience researching naturally occurring, symbiotic microorganisms to develop a probiotic formula that would colonize the entire GI tract with well documented strains. He authored seven U.S. Patents that protected the unique delivery through harsh stomach acid as well as the special prebiotic stimulation with LactoStim®.
As a scientist, Randy knew that he would need help spreading the word on this breakthrough probiotic so he partnered with Jeff Thurston, a seasoned sales and marketing executive, who promptly took the torch and began attending countless healthcare professional events and trade shows. These professionals became Master Supplements' foundation and they were clearly excited about the positive results. Word of mouth became our greatest advertising and soon Theralac was reaching retailers, professionals, and consumers around the world. In the years that followed, a full line of digestive health products were developed that matched Theralac’s high standards and proven efficacy.
Leadership Driving Innovation
Master Supplements Inc.'s strength lies in its leadership team—combining scientific curiosity, business strategy, clinical education, and industry expertise to bring best-in-class nutritional science to market.
Senior Partner & Scientific Strategist
Jeff Thurston
Jeff Thurston brings a uniquely broad scientific perspective to Master Supplements, having spent decades working at the intersection of microbial science, enzyme research, organic agriculture, and nutritional product development. His expertise has been instrumental in shaping the company's systems-based approach to health—emphasizing the interconnection between digestion, immunity, detoxification, and cellular resilience.
Chief Executive Officer, President
Jeff Porubcan
Jeff Porubcan serves as CEO of Master Supplements Inc., overseeing the organization's strategic vision and long-term growth, including U.S. Enzymes and Tomorrow's Nutrition PRO. Under Jeff's leadership, the company has expanded from a respected probiotic innovator into a multi-brand nutritional science organization.
Chief Financial Officer, Vice President
Sonja Yonak
Sonja Yonak plays a critical role in supporting organizational growth, strategic initiatives, and partner relationships across the Master Supplements family of brands. As our in-house microbiologist—having worked with Randy Porubcan across three separate labs—Sonja ensures that his original dedication and passion for science is honored in every product and formula the company brings to market.
Education & Clinical Communications
Roland Pankewich
Roland Pankewich leads educational strategy and scientific communication for the organization, translating complex nutritional science into actionable knowledge for healthcare practitioners, retail partners, consumers, and clinical teams. He conducts our monthly webinars and product trainings, and is the host of the Following Your Gut Podcast—exploring emerging topics in gut health, functional wellness, and clinical nutrition.
Our Products
We hold ourselves to a higher standard.
