Here is Your Fill on Fillers

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The Pure TheraPro Team

The Pure TheraPro Education Team is comprised of researchers from diverse backgrounds including nutrition, functional medicine, fitness, supplement formulation & food science. All articles have been reviewed for content, accuracy, and compliance by a holistic integrative nutritionist certified by an accredited institution.
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What’s in your supplements? Are you reading the labels? What’s in the other ingredients?

The active ingredients in your supplements are the reason you take them, and you’re likely taking supplements because you want to enhance your health and wellness. Fillers, excipients, flow agents, coatings, sweeteners, flavorings and coloring agents, however, defeat your purpose! They may be interfering with the absorption of the active ingredients. These “inactive ingredients” may also affect your overall health, as some have been linked to gut issues, inflammation and even cancer. 

So, why do many supplement companies use these inactive ingredients in their formulations? The inactive ingredients play a role in machine efficiency, keeping costs down and making supplements more aesthetic to consumers. They are not about enhancing your health and wellness. 



Magnesium stearate, silicone dioxide, titanium dioxide, corn starch, stearic acid, propylene glycol and talc are some of these inactive ingredients. Many of these also can contribute to health issues. What’s concerning is that supplement companies don’t always list the inactive ingredients in their products on their product labels. 

Additives Make Your Supplements Look Pretty:

According to the FDA, artificial colors are added to mask natural variations in color that occur within the raw materials as well as the color loss that simply occurs under storage conditions, exposure to light, temperature variances, moisture in the air and other elements that impact the color but the not the potency of the raw materials. This masking, however, comes with a cost to your health, and the FDA is aware of this. Color agents are chemicals that are used in paints, roofing and building materials. Many are synthetic ingredients with toxic effects in humans. 

Red #40 has been linked with ADHD and hyperactivity in children as well as different cancers. Titanium dioxide is also used as a pigment in supplements and accounts for 70% of the total production volume of pigments worldwide. Research has indicated that titanium dioxide has carcinogenic effects and may cause systemic inflammation and other health issues, such as immunosuppression. The International Agency for Research on Cancer (IARC) lists titanium Dioxide as a possible carcinogen. 

Fillers may also be used to mask the natural variances that occur with raw materials which alter their color, creating a more consistent appearance. These fillers, however, aren’t necessary, provide no health benefits and can actually hinder the absorption and bioavailability of the raw materials. 

The question that is posed on consumers is this-- would you rather your supplements look good or be good for you?



Additives Help Manufacturers Make More Money--at a Cost to You:

Magnesium stearate is a simple salt created when magnesium ions bond to stearic acid, which is a fatty acid. The result is actually a lubricant used in over 95% of supplements for manufacturing purposes. Magnesium stearate prevents capsules and tablets from sticking to one another and to machinery during production, helping cut production costs.

According to a 1990 study, stearic acid causes the collapse of cell membrane integrity. Stearic acid was shown to suppress the action of T-cells, a key component of the immune system. Because magnesium stearate is in so many supplements, if you are taking a variety containing this excipient, it may pose a risk to your health. The study indicates that “high amounts of magnesium stearate act as an immuno-suppressor.” But what exactly is considered high amounts? Everyone’s toxic load has an individual limit. Prolonged use over years may increase this toxic load and have detrimental health effects in people with immune system and detoxification issues, such as MTHFR. More studies are necessary to better understand the effects on immune function.

Magnesium stearate decreases the absorption rates of tablets and capsules, reducing the efficacy of your supplements. Because it coats the tablet or capsule, your digestive enzymes must break down the magnesium stearate first in order to receive the nutrients/vitamins in the tablet or capsule. This reduces the absorption rate. A study demonstrates that stearates reduce the dissolution rate of capsules by 65%, which may affect where the nutrients are dissolved in your digestive tract, impacting absorption rates. This is most concerning to individuals with already- existing digestive issues that impair nutrient absorption, such as Leaky Gut Syndrome, SIBO, Crohn's, Ulcerative Colitis and other gut issues. Magnesium stearate may also irritate the bowel mucosal lining, causing digestive issues, such as chronic diarrhea.  

Again, the question is posed to consumers--purchase a risky product that may cost less (and profit the manufacturer more) or one with the mission for purity, potency and quality?



Additives Make Capsules Look More Full:

Benign ingredients such as rice flour, calcium, lactose and cornstarch simply serve as bulking agents to add “fluff’ to capsules in order to make the capsule appear full. Raw material variances can affect the product's density, meaning that the raw materials sink into the capsules, leaving visible space in spite of containing the correct amount of raw materials per capsule. Adding these fillers minimizes capsule gaps to make the capsule contents look completely full. These added ingredients not only provide no nutrient benefit, they may affect the bioavailability and absorption of the raw materials. 

Additives may block the natural synergy that occurs with minerals and phytonutrients, and this type of unnatural intrusion simply for appearances is not in line with our mission of creating the purest supplements possible. At Pure TheraPro Rx, we will always put purity and potency first in order to provide our customers with the highest quality products at affordable prices. 

As a small family-owned company, our mission at Pure TheraPro Rx has always been to help others with chronic illness to find natural solutions through our products. This is why we refuse to add fillers (rice flour, corn starch, cellulose etc) to our products in order to fill the space in the capsules and bulk them up. Third party testing of all of our products ensures that what is on our label is in our products. Nothing hidden. 



All of our products are third party laboratory tested post-production for potency, heavy metals and other contaminants. Our lab has the highest level of certification “NSF” and is also cGMP Certified (Current Good Manufacturing Process) with strict FDA compliance. These are a few of the measures Pure TheraPro Rx uses to ensure the consistent quality and potency of our formulas. In addition, our production facility and formulas have physician and scientist oversight. We are also meticulous to ensure our supplements are free of all common allergens. In other words, what is on the label must be in the bottle - no fillers, no excipients, no junk. 

All products are made in the USA; no raw materials are from China. Unlike most other supplement companies, the ingredients that go into our supplements are not selected based on cost. Instead, they are selected based on purity (to ensure contaminants such as microbes and heavy metals comply with regulatory GMP requirements), potency, and chosen based on successful scientific research. Additionally, patented ingredients are utilized when appropriate.

Purity is our Priority. 


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