"FILLERS" in Dietary Supplements: What are they really?

The truth about fillers. (Warning: This may shock you)

When you look at the label on your supplements you may see a list of ingredients that seem foreign. Manufacturers include these ingredients to meet several key criteria such as stabilization of products, improve flowability, enhance bioavailability, and other functional benefits. These ingredients are called excipients (or “fillers”). We’re going to explore what they are, how they’re used and if they’re even safe.

Excipients are added to dietary supplements to stabilize the supplement, improve its flowability and enhance bioavailability. A few key examples:

• Stabilizers: These ingredients help prevent ingredients from degrading during manufacturing or storage. They can include gums and other agents that bind with water, preventing moisture loss in dry mixes.
• Flow Agents: These ingredients keep powder mixes flowing when they're poured out of their bags or jars so you don't end up with a big mess on your hands (literally). Common flow agents include cellulose powders like microcrystalline cellulose and silicon dioxide powders like colloidal silicon dioxide (also known as silica), but any insoluble substance can be used as a flow agent if it's ground finely enough to pass through tiny holes without clogging them up too much.
• Disintegrants: These are added to tablets so that they fall apart quickly in water after being swallowed by consumers; this makes them easier for our bodies to break down into smaller pieces that can then enter our bloodstream more easily than large chunks would allow them access.

Excipients are considered inactive to the body. In pharmaceuticals, excipients are beneficial as they might enhance the absorption of active ingredients or create a sustained release of drugs in the body. Manufacturers have come a long way with excipients in dietary supplements for similar results. They can be derived from natural sources or synthetic compounds.

One of the most common complaints about dietary supplements is poor bioavailability (i.e., low absorption by the body). However, there are several factors that influence bioavailability including some listed below. These include:

• Poor solubility
• Poor absorption by the GI tract
• Metabolization before reaching systemic circulation (i.e., metabolism by CYP450 system)
• Active ingredients may be degraded by stomach acid or digestive enzymes
• Active ingredients may be destroyed by heat, light or oxygen
• Active ingredients may be broken down by the liver

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Let's break down the first three complaints.

#1) Poor solubility

Poor solubility is the inability of a substance to dissolve in a solvent, which can be fixed by increasing temperature or pressure. Solubility is dependent on both the chemical properties of the substance and physical properties of the solvent, such as polarity and hydrogen bonding between molecules.

#2) Poor absorption by GI tract

The digestive system is responsible for breaking down food into nutrients that can be absorbed by the body. The digestive system starts in your mouth, continues through your esophagus and stomach, and ends in the large intestine. The liver, pancreas and gallbladder all play a role in this process as well.

The main function of these organs is to break down food into smaller parts that can pass through the intestinal walls into our bloodstreams to carry nutrients to cells throughout our bodies. This breakdown process involves enzymes produced by these organs (which are not part of dietary supplements). Enzymes help us digest food properly so we don't feel bloated after eating too much or feel tired from under-digesting certain foods like meat, dairy products or beans/legumes (soybeans).

There are also many types of enzymes involved with other processes such as absorption of vitamins/minerals from foods eaten at meals; manufacturing bile acids which aid digestion when fats enter small intestine where they're broken down further before entering blood stream; producing hormones needed for proper functioning inside cells etc...

#3) Metabolization before reaching systemic circulation

As with any compound that you eat, your body metabolizes it into smaller components. This process is called metabolism and refers to the sum of all chemical reactions that occur in an organism. Metabolism can be generally divided into two categories: catabolism (breaking down) and anabolism (building up). The compounds that go through this process are known as metabolites.

The metabolic breakdown of a substance can be either oxidative or non-oxidative. Oxidation refers to a reaction that adds oxygen atoms; reduction happens when electrons are removed from their carrier molecule (usually hydrogen)

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When supplement manufacturers use effective excipients, they allow otherwise abrasive or hygroscopic powders to run smoothly on encapsulation or tablet compression machines. They also allow small dosages of vitamins and potent ingredients to be attached to a "carrier" in order to deliver the tiny dosage in a capsule or tablet. Imagine trying to take 3 small specks of Vitamin B12. You need to be able to mix the small specks with other inert powders that allow a homogenous (evenly distributed) blend and delivery of the dosage without causing any compound reactions.

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Common examples of excipients include:

• Stearic acid (vegetable source)
• Calcium phosphate
• Rice flour or rice hull extract
• Silicon dioxide (Silica)
• Microcrystalline cellulose (cellulose)
• Hydroxypropyl Methylcellulose (cellulose)
• Magnesium stearate (vegetable and non-vegetable sources)

The Nitty Gritty

The bottom line is that excipients have been used for decades to improve many things like bioavailability, stability, and the manufacturing process as a whole. Marketers and retail brands have spread fear amongst the consumer market that fillers are toxic and harmful to your health as a unique selling proposition to "differentiate" their brand from others. The reality is that you will most likely NEVER be affected by any given excipient or filler unless you consumed an ungodly amount of it during one sitting - i.e., eat a whole pound of magnesium stearate. To give you even more reassurance, did you know that the FDA and industry as a whole has also been weeding out the "bad" fillers for many years now and there continues to be studies on them to make sure they are not harming us? Well if you didn't know, now you do! Hopefully after reading this, you'll have peace of mind knowing that fillers (excipients) aren't there to harm you and are used to give you the best possible product and consumer experience.