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Frequently Asked Questions


What is a probiotic?

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A probiotic is any supplement containing one or more species of beneficial bacteria intended for human consumption. Probiotics are good bacteria that promote healthy structure and function of your digestive tract and immune system. 

Most probiotic supplements use probiotic bacteria of human origin, typically from the Bifidobacterium or Lactobacillus species. Other bacteria, such as those from the Bacillus and Staphylococci families, can be probiotic in nature as well.

The soil-based probiotics (SBO) designation is for bacteria that is not of human origin but may confer probiotic benefits.

How Do I Store Probiotics?

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For daily users, keep your probiotics refrigerated to guarantee potency through expiration. For infrequent users, keep probiotics frozen for long-term storage.

All of our probiotic supplements are kept in freezers at our Minnesota warehouse to optimize freshness and maximize shelf life. We manufacture our supplements with overages to account for decreases in potency over time and we post third party lab tests that guarantee the potency, activity. and purity of our probiotic supplements online. You can view the independent analysis by entering your lot number at

How do I take probiotics with antibiotics?

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We recommend separating probiotics from antibiotics by at least 2 hours with more time preferred. 

For best results, consult with your healthcare provider to discuss your options.

What is the difference between prebiotics and probiotics?

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Probiotics are living microorganisms, typically bacteria native to the human digestive tract, which aid the body in a plethora of digestive processes and support the healthy structure and function of your gut. Commonly found probiotic bacteria include, but are not limited to species from the LactobacilliBifidobacterium, and Bacillus genera.

Prebiotics, on the other hand, consist of anything that stimulates the growth of probiotic bacteria. Vegetables are our primary source of prebiotic nutrition. Garlic, onions, and asparagus all contain high quantities of fiber, promoting the healthy growth and stimulation of probiotics. 

What is the best way to take probiotics?

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Typically, the best way to take probiotics is with a glass of water (or drink of choice) because it takes longer for the bacteria to pass through the stomach safely when taken food. 

What is the best time to take probiotics?

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There is no truly "best" time to take probiotics because each of us lives at the behest of countless environmental factors like diet, family, or additional supplementation.

Our general recommendation is to take your probiotics before bed because, while you're asleep, digestive motility slows, enabling the probiotic bacteria additional time to colonize your digestive tract.

Is probiotic deficiency common?

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Yes! In fact, Probiotic deficiency is more common than you think! Numerous lifestyle factors can influence the balance of beneficial bacteria in your intestinal tract including, but not limited to: stress, poor diet, alcohol, travel, and aging.

To be honest, it's hard for a modern person not to have some kind of probiotic deficiency!

Should I take probiotics with or without food?

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Typically, you want to keep probiotics separated from food by about 30 minutes because most probiotic supplements do not have a method to protect the bacteria through the acidic environment in the stomach. Instead, many probiotic manufacturers rely on excessive overage or select strains with mild acid tolerance.

Yet, even in the best case scenario, 99% of these bacteria die in the stomach, long before reaching your small intestine.

Because of this failure rate, many probiotic companies recommend taking their supplements 30 minutes before a meal with a glass of water. The stomach digests liquids in 15-20 minutes because they don't require a lot of acid or digestive effort which minimizes the bacteria's exposure to stomach acid.

On the other hand, it takes closer to 60-90 minutes for your body to begin digesting food which is a lot more time for unprotected probiotics to spend in the stomach. More time spent in the stomach during the digestive process means fewer probiotic bacteria survive. Because the majority of probiotic activity occurs outside the stomach and in the intestinal tract, you can see why they make this recommendation.

However, when using our probiotics, it does not matter whether or not you take them before, during, or after mealtime.

How do we do it?

Our patented delivery system utilizes dehydrated sodium alginate to ensure that all the bacteria and enzymes pass through the stomach unharmed with or without food or drink. 

If you're unfamiliar with sodium alginate, it helps to think about seaweed -- not the sushi kind, but the type that gets washed up on beaches and wrapped around your ankles in the ocean. You know how it's slimy and mildly gross to touch? Sodium alginate is responsible for that slimy texture seaweed is known for!

In an acidic environment, sodium alginate forms a gel matrix (a fancy word for that slimy feeling you're familiar with), creating a protective barrier between the probiotic bacteria in one of our capsules and the hydrochloric acid produced by your stomach. Once it's past the stomach and in the pH-neutral environment in your small intestine, the protective barrier dissolves, safely releasing the probiotic bacteria deep into your digestive tract where they can proliferate and promote the healthy function of your digestive system.

How do Probiotics Work?

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Probiotic bacteria attach to the soft lining (wall) of your intestinal tract and help reinforce the healthy structure and function of your GI system.

Lactobacillus probiotic strains colonize best in the small intestine whereas Bifidobacterium probiotic strains primarily grow within the large intestine (colon).

Beneficial bacteria repopulate your digestive tract with billions of living organisms that support healthy digestion, elimination, and encourage the optimal absorption of vitamins and minerals.

What is the Best Way to Take Probiotic Powder?

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Stir Granular Theralac into soft foods like applesauce or yogurt or add 1/4 tsp. to your next smoothie! 

Our arrive alive technology prevents this probiotic powder from dissolving in water so we do not recommend adding it to liquids directly.

What is a CFU?

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CFU (colony-forming units) is a unit of measurement used to estimate the number of viable bacterial colonies that form on a petri dish.

Viability is an organism's ability to reproduce. CFU is calculated by counting the number of viable colonies that form on a petri dish.

Colonies are only visible if they have reproduced significantly which implies that the sample is both viable and healthy. Once a plate has visible colonization, the CFU can be calculated for that sample.

Can I take too many probiotics?

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Your intestinal tract contains over 100 trillion microorganisms from over 1,000 different species. Probiotic bacteria, including those in our products, have been used in dosages of one trillion CFU/day or more without harmful effects. 

Human beings have been eating fermented foods and beverages since time immemorial but only recently has the connection between gut health and probiotic consumption been probed by researchers. Probiotic bacteria are generally recognized as safe (GRAS) by the FDA; however, not all strains are created equal and some may be more potent than others which is why it's important to always read the labels on whatever supplement you're considering.

Try to find a probiotic that uses strains that are both of human origin and have a history of evaluation by independent researchers. With the advent of cell phones, it has never been easier to run a quick Google search to see if the strains in your probiotic have been studied and to learn about the potential benefits they may provide.

Lastly, we recommend consulting with a doctor before attempting to take an extra large dose of probiotics. Because everyone's microbiome has a unique bacterial footprint, even small doses of probiotics may lead to gas, bloating, and digestive unrest in certain individuals so it's important to consult with a healthcare provider to find a probiotic supplement that will work for you.

What Do Probiotics Do?

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Probiotic bacteria work by attaching and adhering to the soft lining of your intestinal tract. After adherence, they begin to eat the same food you eat, converting it into lactic acid. Lactic acid is the primary mechanism probiotic bacteria use to promote a healthy digestive system.

As they grow and reproduce, probiotics keep your digestive tract healthy by promoting the growth of all beneficial bacteria which colonize the intestinal walls which further stimulates the growth of other beneficial microorganisms.

Lactobacillus ("lacto") strains are most active in the small intestine while Bifidobacterium ("bifido") strains work best in the large intestine.


What are prebiotics?

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Prebiotics are foods or supplements that stimulate the growth of probiotic bacteria. Foods high in prebiotic nutrients include: garlic, jerusalem artichokes, leeks, asparagus, onions, oats, cocoa, and chicory.

Our probiotics contain two prebiotics: Lactostim, a prebiotic comprised of lecithin and oleic acid that works by emulsifying fats and rehydrating the bacteria so they can start propagating faster in your digestive tract and sodium alginate which works double duty as both a protector and a food source for our probiotics.

What is the difference between prebiotics and probiotics?

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Probiotics are living microorganisms, typically bacteria native to the human digestive tract, which aid the body in a plethora of digestive processes and support the healthy structure and function of your gut. Commonly found probiotic bacteria include, but are not limited to species from the LactobacilliBifidobacterium, and Bacillus genera.

Prebiotics, on the other hand, consist of anything that stimulates the growth of probiotic bacteria. Vegetables are our primary source of prebiotic nutrition. Garlic, onions, and asparagus all contain high quantities of fiber, promoting the healthy growth and stimulation of probiotics. 

Do fructooligosaccharides benefit probiotics?

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Yes. Fructooligosaccharides (FOS) are prebiotic carbohydrates that stimulate probiotic growth. Some foods rich in FOS are artichokes, garlic, chicory, onions, and bananas. 

As a soluble fiber, FOS absorbs water to help your body maintain regularity. Additionally, some fructooligosaccharides are low-calorie sweeteners that can be used as a sugar alternative; however, they can cause gas in some individuals when taken as a supplement. 

Orders & Shipping

Do you ship with ice packs?

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We do not.

To study the effects heat has on our products, we placed a bottle of Theralac in a 100 degree F temperature controlled environment for 14 days and determined that it remained above its guarantee. Therefore, it is our conclusion that 2-3 days spent in transit isn't enough time to irreparably damage the probiotic organisms within our supplements.

It is important to note that probiotics do not go bad or spoil like a carton of milk would in high temperatures. Our Totally Inert Packaging, which includes amber glass bottles, anti-oxygen and anti-moisture desiccant packets, a nitrogen flush, triple seal, and rayon wadding provides optimum stability and freshness. 

Additionally, to counteract any potential loss of viability from improper storage, we blend our probiotics with vast overage in bacterial counts to guarantee that we can deliver the full listed potency throughout the entire two-year shelf life. We have been posting online, third-party lab test results verifying potency online since 2003 and you can check the official bacterial count for your lot here.

With 15 years of third party testing and experience shipping worldwide, we 100% guarantee potency through expiration when our products are shipped without an ice pack.

Can I travel with my supplements?

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Absolutely! Take a bottle on your next trip and place it in the refrigerator or a cool, dark place upon arriving at your destination. If either of those isn't an option, consider taking as many capsules as you think you'll need in a pill box or check out our Travel Packs!

What if I'm unsatisfied with my purchase?

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We offer a 60 Day Money Back Guarantee for all orders placed directly with Master Supplements. If you are not 100% satisfied with your purchase, we encourage you to contact us to speak with one of our customer service representatives. If you purchased through a third party, please contact the retailer from whom you purchased.

What is Totally Inert Packaging?

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Totally Inert Packaging (TIP) is our multi-step approach to ensuring guaranteed potency through expiration for all of our probiotic supplements.

We take these steps because it's important to minimize exposure. Because probiotic bacteria are living organisms, they have the same requirements for life as you or I -- without oxygen and water, probiotics cannot grow.

Most probiotic bacteria have been freeze dried during production to keep them in metabolic stasis. As we introduce moisture and oxygen, the once dehydrated probiotic bacteria wake up and begin reproducing or colonizing.

You want the probiotic bacteria to grow and colonize in your gut, not on the shelf.

Therefore, preventing the ingress of moisture and oxygen during storage is essential to ensure that your supplements remain potent through their expiration date.

Packaging Probiotics:

After encapsulation, we pour our probiotic capsules into a glass bottle. We specifically use brown glass bottles for two reasons:

They block UV lightThey allow less external moisture contamination

Probiotic bacteria are as sensitive to UV radiation as you or I and amber glass bottles block more UV light than clear, green, or blue glass bottles. Additionally, glass bottles have a lower moisture-vapor transmission rate. What this means is that water can more readily pass through a plastic packaing barrier and increase the relative humidity inside a plastic bottle.

Next, we add moisture and oxygen dessicant packets followed up by a pure nitrogen flush of the inside of each bottle.

These packets absorb whatever leftover excess oxygen and moisture remaining inside the product after we flush the bottles with pure N2. By minimizing the oxygen and moisture content, we can guarantee that the probiotics within will remain inert until you're ready to start taking them!

Lastly, we apply a double seal complete with another set of moisture and oxygen barriers to finish our TIP process. 

By limiting their exposure, we can guarantee that our supplements will remain stable and potent through expiration.

How is My Order Shipped?

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We provide same day shipping for all orders placed before 3:00 P.M. Central Time. We ship using USPS Priority Mail so your order will arrive as quickly as possible. Typically, shipments arrive within 2 - 3 days.

During the holiday season, postal carriers see a massive increase in volume which may lead to delays.

We provide tracking information for all accounts that have an associated email address so you can keep tabs on when your supplements are scheduled to arrive. If you do not see this email, check your spam folder.

If you wish to have your order shipped via UPS or have another special request, such as C.O.D., please call Customer Service to place your order. We're happy to ship internationally however additional shipping charges may apply.

Based in Science

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.

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