Introduction
A supplement label contains a lot of important information, but reading it can feel confusing. The active ingredient amount isn't always the same as the capsule weight, percentages can be misleading, and the excipient list is sometimes long. This guide teaches you to read labels like a professional — so you know exactly what you're buying.
Active Ingredient vs Total Weight
This is the most common source of confusion. A capsule may weigh 500 mg, but contain only 200 mg of active ingredient. The rest is excipients, capsule shell, or the mineral compound weight.
Example with magnesium citrate:
- Capsule weight: 500 mg
- Magnesium citrate: 500 mg
- Elemental magnesium: ~80 mg
What matters is the elemental (actual) active ingredient amount. A good manufacturer shows this clearly.
What to look for:
- "Elemental" amount (e.g., "elemental magnesium 200 mg")
- Active ingredient on a separate line in the nutrition table
- Not just the compound name, but the actual content
NRV / RDA Percentages
NRV (Nutrient Reference Value) is the EU standard showing what proportion of your daily requirement one serving covers.
- 100% NRV = covers the standard daily requirement
- >100% NRV = doesn't automatically mean too much (some nutrients have a higher safety limit)
- No NRV listed = no established daily reference for that nutrient (e.g., omega-3, probiotics)
Important: NRV is calculated for the average adult. Athletes, pregnant women, and elderly individuals may need more.
"Proprietary Blends" — A Red Flag
Some manufacturers use "proprietary blends" where ingredients are listed, but individual amounts are not — only the total blend weight.
Why this is a problem:
- You don't know how much of each ingredient is actually present
- The expensive ingredient might be minimally added
- You can't assess whether the dose is effective
A good supplement lists each active ingredient's amount separately.
Excipient List
Excipients are necessary for capsule manufacturing, but some are better than others.
Common acceptable excipients:
- Microcrystalline cellulose (filler)
- Magnesium stearate (flow agent)
- Hydroxypropyl methylcellulose (capsule shell)
- Silicon dioxide (anti-caking agent)
What to avoid (if you prefer cleaner products):
- Artificial colours
- Artificial flavours
- Excessive added sugar
- Titanium dioxide (banned in EU food supplements since 2022; European Commission, 2011)
EU Regulation Requirements
Food supplements sold in the European Union must follow strict labelling rules:
- Nutritional information — active ingredient amounts per daily serving
- NRV percentages — where established for the nutrient
- Recommended daily dose — clear usage instructions
- Warning — "A food supplement is not a substitute for a varied and balanced diet"
- Allergen labelling — mandatory for 14 major allergens
- Storage conditions and expiry date
- Manufacturer/importer details
Step-by-Step: How to Evaluate a Supplement
- Check active ingredient amount — is it the elemental amount?
- Look at NRV percentage — is the dose reasonable?
- Check the form — some forms are better absorbed (e.g., magnesium glycinate vs magnesium oxide)
- Read the excipient list — anything you'd prefer to avoid?
- Check allergens — especially gluten, soy, dairy, nuts
- Look at servings per container — sometimes a "serving" is 2-3 capsules
- Calculate price per serving — a cheaper package isn't always better value
Common Mistakes
- Confusing capsule weight with active ingredient amount — 500 mg capsule doesn't mean 500 mg active ingredient
- Ignoring NRV numbers — 1000% NRV doesn't mean 10x more effective
- Not noticing serving size — "one serving" may be 3 capsules
- Choosing the cheapest product — price per serving and ingredient form matter more than package price
- Ignoring allergens — especially lactose and gluten in hidden sources
Frequently Asked Questions
Does "100% natural" mean the product is better? Not necessarily. "Natural" isn't a strictly regulated term in the EU for food supplements. Look at the ingredients, not marketing words.
Why do some products show 3000% NRV? Some nutrients (like B12) have a very low NRV but a higher safe intake limit. A high percentage doesn't automatically mean an overdose.
Do I always need to check the elemental amount? Yes, it's the only way to know how much active ingredient you're actually getting.
How do I know if a supplement meets EU requirements? Look for mandatory EU label elements: nutritional information, NRV percentages, warning statement, manufacturer details, and expiry date.
Is there a difference between capsules and tablets? Capsules typically break down faster. Tablets may contain more excipients for pressing. Both are fine — choose by preference.
References
- EFSA Panel on Dietetic Products, Nutrition and Allergies. (2012). Scientific opinion on the tolerable upper intake level of vitamin D. EFSA Journal, 10(7), 2813.
- European Commission. (2011). Regulation (EU) No 1169/2011 on the provision of food information to consumers. Official Journal of the European Union, L 304, 18-63.
- Dwyer JT, Coates PM, Smith MJ. (2018). Dietary supplements: regulatory challenges and research resources. Nutrients, 10(1), 41.
See also:
Browse our supplement selection at MaxFit.ee →
Disclaimer
A food supplement is not a substitute for a varied and balanced diet and a healthy lifestyle.
