EAA (Essential Amino Acid) powder is a popular supplement used by athletes, bodybuilders, and fitness enthusiasts to support muscle protein synthesis, recovery, and overall performance. If you’re planning to fill your own capsules with EAA powder, choosing the correct capsule size is important because amino acids tend to have a relatively low bulk density, meaning they can take up a significant amount of space.
What Are EAAs?
Essential Amino Acids are amino acids that the body cannot produce on its own and must obtain through food or supplementation. The nine essential amino acids are:
- Leucine
- Isoleucine
- Valine
- Lysine
- Methionine
- Phenylalanine
- Threonine
- Tryptophan
- Histidine
Most EAA powders contain a blend of these amino acids and are commonly consumed before, during, or after exercise.
Best Capsule Size for EAA Powder
Because EAA powders are generally fluffy and lightweight, larger capsule sizes are usually recommended.
| Capsule Size | Approximate EAA Powder Capacity |
|---|---|
| Size 000 | 900–1,300 mg |
| Size 00 | 650–950 mg |
| Size 0 | 450–700 mg |
| Size 1 | 350–550 mg |
| Size 2 | 250–400 mg |
Actual capacities vary depending on the specific EAA formula, particle size, moisture content, and packing method.
Recommended Choice
For most users, Size 00 capsules offer the best balance between capacity and ease of swallowing.
If you want to minimise the number of capsules needed per serving, Size 000 capsules are often the most practical option.
Example EAA Serving
A typical EAA serving ranges from 5g to 10g.
| Serving Size | Size 000 Capsules Needed | Size 00 Capsules Needed |
|---|---|---|
| 5g | 4–6 capsules | 6–8 capsules |
| 10g | 8–12 capsules | 11–16 capsules |
This is why many users prefer taking EAA powder mixed into a drink rather than encapsulating full servings.
Gelatin vs Vegetarian Capsules
Both capsule types work well with EAA powder:
- Gelatin capsules are economical and easy to fill.
- HPMC vegetarian capsules are suitable for vegan and vegetarian users.
- Both provide similar filling performance for amino acid powders.
Tips for Filling EAA Capsules
- Use a capsule filling machine for consistent results.
- Sieve the powder if it contains clumps.
- Lightly tamp the powder to maximise fill weight.
- Store filled capsules in a cool, dry environment.
- Test a small batch first to determine your actual fill weight.
Why Density Matters
Not all EAA powders are identical. Different manufacturers use varying amino acid ratios and processing methods, which can significantly affect bulk density.
For example:
- Fine powders generally fit more material into a capsule.
- Granulated powders may require larger capsule sizes.
- Flavoured EAA powders often contain additional ingredients that reduce density.
Because of these differences, the best approach is to weigh a few test capsules before producing larger batches.
Frequently Asked Questions
Can EAA powder fit into Size 0 capsules?
Yes, but you’ll need significantly more capsules per serving. Size 0 capsules typically hold around 450–700 mg of EAA powder.
Are Size 000 capsules too large?
Size 000 capsules are the largest commonly available empty capsules. While some people find them large, they are ideal when trying to encapsulate bulky supplements such as EAAs.
Do EAAs compress well?
Most EAA powders compress moderately well, allowing slightly higher fill weights when tamped during the filling process.
Which capsule size is best overall?
For most users, Size 00 capsules are the best compromise between capacity, convenience, and ease of swallowing.