Are supplement excipients safe?

Excipients are substances added to supplements to facilitate manufacturing, improve stability, enhance bioavailability, modify the physical characteristics and reduce cost. Here are some common ones:

Fillers & Binders

  • Help maintain the shape and form of supplement tablets and capsules

  • Include Microcrystalline cellulose; Dicalcium phosphate; Calcium carbonate; Magnesium stearate; Silicon dioxide

  • Potential for allergic reactions; Digestive issues; Concerns about the safety / purity of their source

Flow Agents

  • Prevent ingredients from clumping and help ensure uniform distribution within

  • Include Magnesium stearate; Silicon dioxide; Calcium stearate

  • Potentially contain allergens or synthetic additives; Digestive discomfort; Concerns about long-term health effects

Coatings

  • Applied to tablets to improve appearance, taste and swallowability, and protect ingredients from moisture and oxidation

  • Include Hydroxypropyl methylcellulose (HPMC); Polyethylene glycol (PEG); Shellac; Titanium dioxide

  • Potentially cause allergic reactions/intolerances; May contain synthetic chemicals or additives; Concerns about their source and safety

Disintegrants

  • Help tablets and capsules break down and release contents once ingested, facilitating absorption

  • Include Croscarmellose sodium; Crosslinked sodium carboxymethylcellulose; Sodium starch glycolate

  • May cause gastrointestinal discomfort or digestive issues; Concerns about safety and potential interactions with other ingredients; Potential sensitivities

Preservatives

  • Added to extend shelf life and prevent microbial contamination

  • Include Vitamin E (tocopherols); Ascorbic acid (vit C); Potassium sorbate; Sodium benzoate (may be synthetic)

  • Risk of allergic reactions/sensitivities; Concerns about the safety and long-term health effects of synthetic additives; Potential for adverse reactions or

Colourants

  • Used to enhance appearance and differentiation

  • Include Titanium dioxide; Iron oxides; FD&C dyes (FD&C Red No. 40, FD&C Yellow No. 6)

  • May contain allergens or synthetic additives; Concerns about the long-term health effects of artificial dyes; Potential for allergic reactions / intolerances

Flavouring Agents

  • Added to improve taste, especially in chewable tablets, gummies, or powdered formulations

  • Include Natural flavours (fruits, herbs, spices); Artificial flavours; Sweeteners (sucralose, stevia, sorbitol)

  • Risk of allergic reactions / sensitivities; May contain synthetic chemicals or additives; Concerns about their safety and source

The message?

Read supplement labels carefully.

Also, food-based ones are usually better as your body doesn’t have to put valuable resources into converting them so they’re useable, or into detoxing them.

The cheaper the supplement, the less active ingredients and the more excipients.