What supplements should I take? A method, not a stack.

How do I choose the right supplements?

Choose supplements the way you would run a fair test: one goal, the best evidence for it, a blood test where one applies, a safety check, then one supplement at a time. Many people need fewer supplements than the wellness wave suggests, and some need none. Five steps find the few that fit you.

1. 01Name one goal. Sleep, stress, energy or training. One goal means one metric to watch, and that is what makes a result readable.
2. 02Choose by evidence grade. Start with Strong or Moderate picks; leave Emerging for later and read Caution as a reason to skip.
3. 03Test before ironStrong, vitamin DModerate or B12Moderate. All three help only if you are low, and extra iron can harm you.
4. 04Check interactions and safety. Blood thinners, thyroid medication, SSRIs, blood-pressure medication, sedatives, immunosuppressants, pregnancy and kidney disease all narrow your options.
5. 05Start one at a time and measure. Umbral compares a 21-day trial, logged with a one-tap weekly check-in, against the 14-day baseline your wearable already holds. The verdict reads as association, not causation.

Which supplement is best for your goal?

The best supplement for you is the one with the strongest evidence for your single goal: saffronStrong or AshwagandhaStrong for sleep, Lavender oil (Silexan)Strong for stress, Creatine monohydrateStrong for strength and Beetroot nitrateStrong for endurance. Tiredness starts with a blood test, not a pill. The linked guides go deeper on each goal.

Which supplements have the best evidence?

Six supplements pair a Strong grade with an everyday goal: Omega-3 (EPA+DHA)Strong, AshwagandhaStrong, saffronStrong, Beetroot nitrateStrong, Creatine monohydrateStrong and Lavender oil (Silexan)Strong. They are ranked by grade, then by whether a wearable can see the effect. Strong means the research is solid; the effects themselves are still modest.

What do evidence grades mean?

An evidence grade tells you how much research stands behind a supplement, not how large its effect is. Umbral uses three grades (Strong, Moderate and Emerging) and one flag, Caution, for a safety or interaction concern that outweighs the benefit. One real example of each:

• Strong · multiple randomized trials or meta-analyses. MelatoninStrong: 19 trials agree on about 7 minutes faster sleep onset. Strong evidence, small effect.
• Moderate · some trials, limited replication. MagnesiumModerate: about 17 minutes faster sleep onset, from 3 small trials in older adults with insomnia.
• Emerging · preliminary or mechanistic. PhosphatidylserineEmerging: exercise cortisol about 35% lower in one study of 10 people.
• Caution · interaction or safety flag. EchinaceaCaution: a modest effect at best, against documented allergic reactions including anaphylaxis.

Which supplements need a blood test first?

Three supplements need a blood test first: ironStrong, vitamin DModerate and vitamin B12Moderate. Each helps when you are actually low, does little or nothing when you are not, and iron can do harm. If you are asking which vitamins you should take, start here.

Which supplements interact with medication?

Twenty-five supplements in Umbral's catalog carry a flag for a medication class or a life stage: blood thinners, thyroid medication, SSRIs, blood-pressure medication, sedatives, immunosuppressants, pregnancy and kidney disease. Find your row in the table below before you start anything new.

Specifics: omega-3 slightly lengthens bleeding time, CoQ10 may weaken warfarin, ashwagandha raises thyroid hormones and melatonin also interacts with contraceptives. This is not a full interaction check: talk to a clinician before starting.

How do you buy a supplement you can trust?

Buy the form the trials tested, from a brand that proves what is in the bottle. Labels are not always accurate and some categories carry documented contamination, so third-party testing and a certificate of analysis matter more than price or packaging. Five cases from the catalog:

• MelatoninStrong: measured content ran from 83% below to 478% above the label. Choose third-party-tested, USP-verified products.
• Whey proteinStrong: look for Informed Sport or NSF certification.
• CordycepsEmerging: wild Cordyceps sinensis is often adulterated, with documented lead and arsenic. Buy cultivated C. militaris or Cs-4, never a mushroom blend.
• Citrulline malateModerate: check the 2:1 ratio on the certificate of analysis; many products deliver 1.1:1, about half the labeled citrulline.
• Cocoa flavanolsModerate: cocoa can carry cadmium, so prefer brands with third-party heavy-metal testing.

What we left out and why

Some popular supplements are not in Umbral's recommendations, and two more carry a Caution flag. If the evidence is thin or the risk is real, it does not belong on your shelf.

• Kava: reports of liver toxicity; banned or under warnings in several countries.
• Valerian: people rated their sleep better, but actigraphy showed no objective change.
• Oral GABA: doubtful that it crosses the blood–brain barrier; low-quality evidence.
• EchinaceaCaution: nothing measurable once you are sick, and anaphylaxis and acute asthma are documented.
• Vitamin B6 (pyridoxine)Caution: the doses that eased premenstrual symptoms (50–600 mg/day) sit above EFSA's 12 mg/day upper limit, and high doses over time can damage nerves.

How do you know if a supplement is working?

A supplement is working for you when your own metric shifts while you take it and moves beyond its usual night-to-night swing. That needs an effect big enough for a wearable to see, so check the tier first: visible, real but hidden, or out of reach.

• Visible (tier A): Omega-3 (EPA+DHA)Strong lowers resting heart rate about 2.2 bpm over 8–12 weeks; Tart cherryModerate added about 34 minutes of sleep a night in a one-week trial; Beetroot nitrateStrong feeds VO₂ max estimates.
• Real but hidden (tier B): MelatoninStrong speeds sleep onset by about 7 minutes, while sleep onset swings about 20 minutes night to night. Creatine monohydrateStrong and MagnesiumModerate sit here too.
• Out of reach (tier C): daily vitamin CModerate shortens colds about 8%, which no wearable metric tracks.

Umbral keeps the test fair: a 14-day baseline your wearable already recorded, one supplement for 21 days with a one-tap weekly check-in, and a verdict after at least 7 nights on each side, read as association, not causation. Connect the wearable you already own, start one supplement, and measure it against your own band.

Frequently asked questions