Swanson Values / Quality Control & Testing / Additives & Fillers in Vitamins and Supplements

Excipients (Fillers, Binders and Flow Agents)

During the supplement manufacturing process, excipients play an important role in producing high quality, consistent tablets, capsules and softgels in a cost effective manner. Excipients are a class of raw materials that includes fillers, binders and flow agents.

What Are Fillers?

During the supplement manufacturing process, excipients play an important role in producing high quality, consistent tablets, capsules and softgels in a cost effective manner. Excipients are a class of raw materials that includes fillers, binders and flow agents.

As batch size is often limited by the blender capacity, using less filler is more advantageous from a manufacturing standpoint. Unfortunately in most situations, fillers cannot be completely avoided. Common fillers used are rice flour, microcrystalline cellulose, starch and calcium phosphates. Carrier oils may come from a variety of sources such as soy and other vegetable oils.

What Are Binders?

Binders are used during the tableting process to ensure that the tablet compresses and binds properly. Without the appropriate amount of binder, a tablet may break apart easily, chip, crack or crumble. Some raw materials such as cellulose and calcium phosphate may serve dual roles as both a filler and a binder.

What Are Flow Agents?

Flow agents (also known as glidants and lubricants) are used to enhance the ability of an ingredient or product to flow and reduce stickiness of dietary ingredients. Some flow agents can also serve as densifiers, helping particles fit together better, which results in a smaller capsule or tablet that would not be possible without the flow agent. Many flow agents are effective when used at very low levels (under 1%) in a blend. Different flow agents perform different functions when added to a blend. Silicone dioxide (silica) is effective at reducing stickiness of powders, while magnesium stearate is more effective at preventing build-up on machine surfaces and improving the flow/compaction of powders. Other types of flow agents include stearic acid, rice bran extract, calcium laurate, talc or calcium palmitate.

Whenever possible, we manufacture products without using flow agents; however, some products can simply not be made without them.