The shell is the one ingredient nobody markets and the first one to act. It decides when the contents are released, roughly where, and for a meaningful number of people whether the product is usable at all.
Gelatin
The traditional shell, and the one used in VapoCept®. Gelatin is animal-derived — here bovine — and it dissolves readily in stomach acid, typically opening within a few minutes of arriving.
Two practical consequences. It releases early and reliably, which is what you want for ingredients that are then going to meet a meal in the small intestine. And it is cattle protein, so a vegetarian or vegan diet rules the product out and no halal or kosher certification applies.
That second point is the detail most likely to rule a product out for someone, which is why it belongs on the front of the discussion rather than in the small print.
HPMC, the plant-derived alternative
Hydroxypropyl methylcellulose, made from plant cellulose, is the standard vegetarian capsule. It dissolves a little more slowly than gelatin and is less sensitive to moisture, which suits hygroscopic ingredients.
For most purposes the difference in release timing is small enough not to matter. If you need a vegetarian or vegan product, HPMC is what to look for on the panel — "vegetable capsule" or "vegetarian capsule" usually means this.
Enteric coatings, and why they are mostly absent here
An enteric coating resists stomach acid and dissolves further down, in the more alkaline small intestine. It exists to protect compounds that acid would destroy, or to protect the stomach from compounds that irritate it.
Probiotics and fish oil commonly use them. Botanical brain formulas generally do not, for a simple reason: the compounds involved survive stomach acid, and delaying release past the point where bile and dietary fat are present would work against the fat-soluble ingredients rather than for them.
The other two inactive ingredients
Magnesium stearate is a flow agent. Powder has to move through encapsulation machinery without sticking or bridging, and that is what makes consistent fill weights — and therefore consistent doses — achievable. A few milligrams per capsule.
Microcrystalline cellulose is purified plant fibre used as a bulking agent, so each capsule holds the same volume. Inert, plant-derived, and present in a very large share of capsules and tablets on the market.
Neither has a meaningful effect on absorption at the quantities used, despite periodic claims to the contrary.
What to check on any bottle
- Capsule material, if diet or religious observance matters to you. This is binary and it is on the panel.
- Serving size. One capsule or four changes the cost per day and the odds you finish the bottle.
- Allergen sources. Glucosamine is sometimes shellfish-derived; confirm with the manufacturer if that applies to you.
None of this is exciting. All of it is on the back of the bottle, which is the half worth reading.