Excipients: Functional Ingredients You May Not Know About

Excipients: Functional Ingredients You May Not Know About

What are excipients?

If you’re like most health-savvy individuals, you’ve probably spent your fair share of time trying to make sense of product labels.

And while you may find the ingredients you’ve been looking for listed on the label, you’ve also probably stumbled upon a number of unfamiliar ingredients.

Many of these “minor ingredients” are what we in the business refer to as excipients – substances that contribute functional and structural characteristics to various forms of dietary supplements.

Rarely do excipients contribute any nutritional benefit. Instead, excipients...

  • Make it easier for you to consume and use “active ingredients” comfortably and safely.
  • Ensure production of high quality products on a consistent basis using high-speed packaging equipment.

Like many manufacturers, NOW® uses excipients in our formulations. But make no mistake - we are conservative in our use of excipients...

  • NOW aggressively works to minimize or completely avoid the use of excipients whenever possible.
  • NOW’s formulating scientists use the same rigid standards we apply to all ingredients when approving excipients.
  • NOW provides complete disclosure of all excipients used on every product label.

NOW’s list of approved excipients includes magnesium stearate, stearic acid, cellulose, various colloids, brown and white rice flours, potassium sorbate, and acidulants (acidifiers).

Many of these can be used in a variety of supplements, while others are extremely material-specific. Several excipients have limited applications, as established by FDA regulations. NOW is, and will continue to remain, 100% compliant to these guidelines.

But why? Why even bother to use excipients in dietary supplements?

Here’s why excipients are standard in dietary supplement manufacturing...

Flow Agents

Powder excipients - lubricants and anti-caking agents - are used to help tablets and capsules flow through processing steps with minimal resistance. These non-toxic and vegetarian-friendly compounds include silicon dioxide, magnesium stearate, and stearic acid.

Non-toxic lubricants also allow tablets to be punched and ejected without sticking to the equipment. This ultimately results in products of much better physical quality.


Cellulose-type binders bind ingredients together. Without binders, tablets would not be tablets. And pressed supplements would eventually shed some powder and crumble. Cellulose is a simple wood-pulp derivative. It simply becomes a non-digestible fiber when consumed.

While primarily used to thicken liquid formulations, Colloids also hold ingredients together. They include guar gum, xanthan gum, acacia gum, and cellulose gum. Like cellulose, colloids fall into the fiber category, and carry some nutritional benefits as fibers. These are typically from vegetarian sources.


When dealing with supplement ingredients that are measured by micrograms (mcg), we often need to use carriers. Trace and micro ingredients – like chromium, selenium, iodine, folic acid and biotin - can be difficult to detect by the naked eye. Even with the tiniest of capsules, without carriers, the capsule would appear virtually empty.

NOW uses rice flours as carriers because they are hypoallergenic and naturally occurring complex carbohydrates.


Acidulants and potassium sorbate are essential components in many of today’s liquid concentrate formulas. Here’s why...

Liquid concentrates contain water. And water provides a favorable environment for microbial growth. In order to prevent microbial growth, acidulants and potassium sorbate are used.

Heat processing can be used as an alternative to acidulants in preventing microbial growth. However, many NOW® products contain heat-sensitive ingredients, thus making a cold-processed stabilized product preferable.

Acidulants are safe for human consumption and commonly found in many fruits and vegetables. They include citric acid, malic acid, tartaric acid, and aspartic acid. All are derived from vegetarian sources.

Excipients – used wisely – are a necessary part of supplement manufacturing.

The use of non-toxic excipients allows the equipment to function smoothly and without challenge. In the long run, this helps safeguard the integrity of the supplements being produced. Although excipients do not contribute significant nutritional benefits, their function remains essential.

NOW’s use of excipients, however, is governed with extreme caution and only in limited amounts. We scrutinize excipients like all our ingredients for safety, effectiveness, and quality. We look for ingredients that are safe for people with allergies and acceptable for people who are vegetarian.