Test one supplement at a time

What it is

Adding a single supplement to your routine, logging every dose and every skipped day, and checking whether your own data looks any different. It’s the opposite of starting five things at once and guessing which one helped.

What the research says

How well a supplement is studied depends entirely on the supplement and what it’s taken for, so there’s no general answer. A few things matter for testing it on yourself:

• Some effects show up the same day. Others build over weeks, and some only help if you were low to begin with, which daily data can’t show. Know which kind yours is before you judge it.
• Averages hide differences between people. Studies report group results; your response may be bigger, smaller or absent.
• Daily data is noisy. Sleep, travel and illness move your numbers more than most supplements do, which is why one-change-at-a-time matters.

Metrya’s Stack labels each of its 150 catalog supplements with how well it’s researched for its main purpose, and whether its effect can show up in daily data at all.

How to try it

1. Pick one supplement and one reason (for example, creatine for strength training). Check with a clinician if you take medication or have a health condition.
2. Use the same dose at the same time of day. Write down the start date.
3. Log every day, including skipped days and why you skipped.
4. Keep the rest steady: bedtime, caffeine, training plan.
5. Look at the trend after 4 weeks, and compare days taken with days skipped. Leave out travel and sick days.

Read what you see as a pattern, not proof.