How to Read Supplement Labels
The supplement industry spends billions on marketing. Most of it is designed to confuse you. Here's how to cut through the noise and understand what you're actually buying.
In This Guide
1. Serving Size: The First Trick
Before anything else, check the serving size. This is where companies play their first game.
The Trick:
A product advertises "500mg Vitamin C per serving." Sounds great. But the serving size is 4 capsules. The bottle has 60 capsules. That's only 15 servings, not 60.
What to do: Always calculate the cost per serving, not per bottle. A $30 bottle with 15 servings costs $2/day. A $45 bottle with 60 servings costs $0.75/day.
2. Daily Values: Mostly Useless
The "% Daily Value" on labels is based on government guidelines designed to prevent deficiency diseases, not optimize health. These numbers are often decades old.
Vitamin D DV: 800 IU
Prevents rickets. Many researchers recommend 2,000-5,000 IU for optimal health.
Magnesium DV: 420mg
Bare minimum. Athletes and stressed individuals often need 400-600mg.
What to do: Ignore % DV for most supplements. Instead, look up the clinically effective dose for your specific goal. Our ingredient pages show this for every supplement.
3. Proprietary Blends: The Big Red Flag
This is the supplement industry's favorite trick. A "proprietary blend" lists ingredients but hides the individual doses. Here's why that matters:
What the label shows:
Energy Matrix (1,500mg): Caffeine, L-Tyrosine, Rhodiola, Alpha-GPC, Taurine
What it could mean:
Caffeine (1,480mg) + trace amounts of everything else
Legally, ingredients must be listed in order of weight. But the first ingredient could be 99% of the blend or 20%. You have no way to know.
What Good Labels Look Like:
Every ingredient has its own line with a specific dose. No blends, no hiding.
4. Ingredient Forms: Quality Matters
Not all forms of an ingredient are created equal. The form determines how well your body can actually use it.
| Ingredient | Best Forms | Avoid |
|---|---|---|
| Magnesium | Glycinate, Threonate, Malate | Oxide (only 4% absorbed) |
| Vitamin B12 | Methylcobalamin | Cyanocobalamin |
| Folate | Methylfolate (5-MTHF) | Folic acid (synthetic) |
| CoQ10 | Ubiquinol | Ubiquinone (less absorbed) |
| Zinc | Picolinate, Glycinate | Oxide, Sulfate |
5. What to Actually Look For
Green Flags
- Individual doses listed for every ingredient
- Third-party testing (NSF, USP, Informed Sport)
- Bioavailable forms of ingredients
- Clinical doses matching research studies
Red Flags
- Proprietary blends hiding actual doses
- "Mega doses" of cheap vitamins (1000% DV of B vitamins)
- Too many ingredients (20+ usually means pixie-dusting)
- Marketing claims like "Doctor recommended" or "Clinically proven" without specifics
The Bottom Line
The best supplement labels are boring. No fancy claims, no proprietary blends. Just clear doses of quality ingredients. If a company is hiding information, ask yourself why.
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