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Energy & Performance·Weak Evidence

Nicotinamide Riboside (NR)

9 products scoredLast reviewed May 2026
The Bottom Line

Nicotinamide riboside (NR) is the cleanest NAD+ precursor story on paper and the most disappointing one in human trials.

Evidence
Weak Evidence
Category
Energy & Performance
Best form
Niagen (ChromaDex's branded nicotinamide riboside chloride, FDA NDI accepted, GRAS, used in essentially every published human RCT)
Effective dose
300-1000mg daily
Lab tested
9 of 9 products

Key takeaways

  • NR reliably raises NAD+ in human blood; downstream functional benefits have largely not panned out in well-controlled RCTs.
  • Niagen (ChromaDex) is the form used in essentially every published NR trial. Generic NR is the same molecule but not the trial-grade material.
  • NR is the most legally-clean NAD+ precursor: FDA NDI accepted, GRAS affirmed, broad safety record. NMN was drug-excluded from the supplement market in 2022.
  • The Parkinson's NADPARK trial is the most interesting positive functional signal; metabolic and insulin sensitivity trials in obese adults have been flatly negative.
  • Reasonable to try at 300-1000mg/day if you want a well-tolerated NAD+ booster; do not expect dramatic energy, weight, or anti-aging effects most users describe in marketing.

What Is Nicotinamide Riboside (NR)?

Nicotinamide riboside (NR) is the cleanest NAD+ precursor story on paper and the most disappointing one in human trials. Across well-controlled RCTs at doses from 100mg to 2000mg per day, NR raises whole-blood NAD+ in a dose-dependent and reliable way. Almost everything downstream of that NAD+ rise has either failed to replicate or come in as a null result.

Conze 2019 (n=132, 8 weeks, 100/300/1000mg) is the definitive dose-ranging study and the cleanest demonstration that NR works as a NAD+ booster: 22 percent, 51 percent, and 142 percent NAD+ elevations respectively, all dose-dependent, all statistically significant. Martens 2018 (n=24, 6-week crossover, 1000mg) confirmed roughly 60 percent NAD+ elevation in healthy middle-aged and older adults and reported a roughly 10mmHg systolic blood pressure drop in a small subgroup with stage 1 hypertension. That subgroup signal launched a peripheral artery disease trial and informed dosing in most follow-up work.

The functional outcomes have not held up. Dollerup 2018 (n=40 obese men, 12 weeks, 2000mg/day total) found no improvement in insulin sensitivity, glucose disposal, endogenous glucose production, resting energy expenditure, lipolysis, or body composition. Remie 2020 (n=13 obese adults, 6 weeks, 1000mg/day) doubled muscle NAD+ markers, raised acetylcarnitine, and modestly bumped fat-free mass and sleeping metabolic rate, but found no change in insulin sensitivity by hyperinsulinemic clamp and no mitochondrial function improvement. These were the two best-designed metabolic trials and both came back substantially negative.

The Parkinson's data are the most interesting positive signal. Brakedal 2022 (NADPARK trial, n=30 newly diagnosed treatment-naive PD patients, 30 days at 1000mg) demonstrated that NR augmented brain NAD+ measured by 31P-MRS, altered cerebral glucose metabolism on FDG-PET, and produced mild clinical improvement in patients whose brain NAD+ actually rose. This is a phase I study with a small sample and short duration, and a larger follow-up (NOPARK) is ongoing, but it remains the closest thing to a downstream functional result in human NR trials.

The honest read: NR is regulatorily the cleanest NAD+ precursor on the market. ChromaDex's Niagen has FDA NDI status, GRAS affirmation, and an unusually deep safety record across multiple human RCTs. NMN, which targets the same pathway one step closer to NAD+ itself, was excluded from the supplement market in late 2022 after the FDA accepted an investigational new drug application for it. So if you want the legally-clean NAD+ supplement, NR is the only mainstream option. Just calibrate expectations: the trials reliably raise the biomarker and inconsistently move the functional needle.

Does It Work? The Evidence

How A-F grades work

Elevation of whole-blood NAD+ in healthy adults

ASupported

Conze 2019 (n=132, 8 weeks): 22%/51%/142% NAD+ elevation at 100/300/1000mg dose-dependently; Martens 2018 (n=24, 6 weeks 1000mg): ~60% NAD+ elevation; Trammell 2016 pharmacokinetic study confirms oral bioavailability

Systolic blood pressure and arterial stiffness in pre-hypertensives

CEarly Signal

Martens 2018 (n=24 overall, n=13 subgroup with stage 1 hypertension): ~10mmHg systolic drop in pre-hypertensive subgroup; no effect in the full normotensive sample. Subgroup-level finding from a small primary trial

Insulin sensitivity and glucose metabolism in obese adults

BNot There Yet

Dollerup 2018 (n=40 obese men, 12 weeks, 2000mg/day): no change in insulin sensitivity, glucose disposal, endogenous glucose production, REE, lipolysis, or body composition; Remie 2020 (n=13, 6 weeks 1000mg): no change in insulin sensitivity by hyperinsulinemic clamp despite NAD+ doubling

Skeletal muscle function and mitochondrial capacity

CConflicted

Remie 2020: increased muscle acetylcarnitine and small fat-free mass gain, but no mitochondrial function improvement on biopsy; Dolopikou 2020 and Elhassan 2019 small trials show mixed signals

Cerebral NAD+ elevation and metabolic signaling in Parkinson's disease

CEarly Signal

Brakedal 2022 NADPARK trial (n=30 treatment-naive PD patients, 30 days 1000mg): augmented brain NAD+ on 31P-MRS, altered FDG-PET cerebral metabolism, mild clinical improvement in NAD+ responders; phase I, short duration

Peripheral artery disease walking performance

CNot There Yet

NICE trial 2024 (Martens et al., n=90, 6 months): the most recent functional outcome trial; modest signal for walking distance and mitochondrial markers but did not hit primary endpoint

Anti-aging or lifespan extension in humans

FNot There Yet

No human trial has tested NR for lifespan or hard aging outcomes. Mouse data are mixed and short-lived. All marketing claims about slowed aging are inferences from biomarker shifts, not outcome data

How to Choose: Forms, Doses & What Matters

Clinical dose: 300-1000mg daily; 1000mg is the dose used in the largest healthy-adult and disease-state RCTs

Best forms: Niagen (ChromaDex's branded nicotinamide riboside chloride, FDA NDI accepted, GRAS, used in essentially every published human RCT), Generic nicotinamide riboside (chemically identical to Niagen but not standardized to ChromaDex's specs and not the form tested in human trials), NR + pterostilbene combinations (Elysium Basis, Life Extension NAD+ Cell Regenerator with Resveratrol Elite)

Most healthy-adult trials used 300-1000mg per day as a single morning dose. Conze 2019 found dose-dependent NAD+ elevation across 100mg, 300mg, and 1000mg with diminishing returns above 300mg in some metabolites. The clinical and Parkinson's trials standardized on 1000mg/day. Food is not required; NR is well-absorbed with or without a meal. Effects on NAD+ levels appear within 2 weeks; any functional changes would take 4-12 weeks if they occurred at all. Take with breakfast if you find it activating.

Who Should Take Nicotinamide Riboside (NR)?

Adults curious about NAD+ support who want the legally-cleanest, best-studied precursor on the market. Older adults with pre-hypertension may have a small BP signal worth a trial (Martens 2018 subgroup). People interested in trying NR as an adjunct in early Parkinson's disease under physician guidance, given the NADPARK signal. Anyone choosing between NR and NMN should pick NR, because NMN has been excluded from US supplement sales since late 2022 and NR has the deeper trial record anyway.

Who Should Avoid It?

Not for everyone

Pregnant or breastfeeding women due to insufficient safety data. People expecting dramatic energy, fat loss, or anti-aging effects, because the trial record does not support those claims. People with active cancer should consult their oncologist; NAD+ has complex bidirectional effects on tumor metabolism and the human data are not reassuring enough to recommend casual use. Not a replacement for standard care in any disease.

Side Effects & Safety

Generally very well-tolerated across all trials. Most common: mild GI upset (nausea, loose stools), occasional headache, rare flushing. Conze 2019 reported no significant difference in adverse events between any NR dose group and placebo across 132 participants over 8 weeks. Martens 2018 (1000mg x 6 weeks) and Dollerup 2018 (2000mg x 12 weeks) both reported clean safety profiles. NR-SAFE 2023 (high-dose NR in Parkinson's) extended the safety record at gram-level doses. No signals of liver, kidney, or cardiac toxicity in published trials.

Product Scores

9 products scored on dosing accuracy, third-party testing, cost per effective dose, and label transparency.

The Scorecard: 9 Products Compared

Top Pick
01

Tru Niagen 300mg, 90 Servings

Tru Niagen

93/100
Excellent
$1.10/day300mg/serving$99.00 (90 servings)

$99.00 ÷ 90 days at 300mg/day (1 serving × 300mg)

✓ Third-party testedGMPThird-party tested

If you are committing to NR for a real trial of 8-12 weeks, the 90ct beats the 30ct on per-day cost and matches the published trial cadence

+Best per-day price on genuine Niagen at the 300mg trial dose
+90-day bottle aligns with how trials measure NAD+ effects
+ChromaDex direct ownership of the Niagen supply chain
Still expensive relative to generic NR at similar doses
High sticker price even if per-day cost is reasonable
Dosing
25/25
Purity
22/25
Value
22/25
Transparency
24/25

Prices checked 2026-05-15. Cost shown is per clinically effective daily dose, not per pill.

02

Tru Niagen 300mg, 30 Servings

Tru Niagen

92/100
Excellent
$1.33/day300mg/serving$40.00 (30 servings)

$40.00 ÷ 30 days at 300mg/day (1 serving × 300mg)

✓ Third-party testedGMPThird-party tested

Tru Niagen is the brand ChromaDex built around Niagen and is the product type most directly comparable to what was used in the published NR trials

+ChromaDex's own brand using the exact Niagen tested in Conze 2019
+300mg matches the cleanest NAD+ dose-response data point
+Strongest trial-to-product link in the NR market
Premium pricing at $1.30+/day
30-count bottle runs out fast; 90ct version offers better per-day cost
Dosing
25/25
Purity
22/25
Value
21/25
Transparency
24/25

Prices checked 2026-05-15. Cost shown is per clinically effective daily dose, not per pill.

03

Thorne NiaCel 400, 60 Capsules

Thorne
91/100
Excellent
$1.25/day415mg/serving$75.00 (60 servings)

$75.00 ÷ 60 days at 415mg/day (1 serving × 415mg)

✓ Third-party testedNSF Certified for Sport

The only NR product on Amazon with NSF Certified for Sport, which matters for tested athletes and for people who weight third-party certification heavily

+NSF Certified for Sport - rare for an NR product
+Genuine Niagen at a higher 415mg dose
+Thorne's overall quality and athlete-facing trust
Expensive per cap
Per-cap dose overshoots Conze's optimal 300mg point
Dosing
24/25
Purity
24/25
Value
19/25
Transparency
24/25

Prices checked 2026-05-15. Cost shown is per clinically effective daily dose, not per pill.

04

Thorne NiaCel 250, 60 Capsules

Thorne
89/100
Excellent
$0.80/day250mg/serving$48.00 (60 servings)

$48.00 ÷ 60 days at 250mg/day (1 serving × 250mg)

✓ Third-party testedGMPIn-house tested

Reasonable middle ground for people who already buy Thorne and want a 250mg NR without paying for the NSF Sport certification on NiaCel 400

+Genuine Niagen at the 250mg dose, close to the trial sweet spot
+Thorne brand quality without the NiaCel 400 price
+Easy to split-dose at 1-2 caps/day
Not NSF Certified for Sport (the NiaCel 400 is)
Less per-mg value than Tru Niagen's 90ct
Dosing
24/25
Purity
22/25
Value
20/25
Transparency
23/25

Prices checked 2026-05-15. Cost shown is per clinically effective daily dose, not per pill.

05

Nicotinamide Riboside Capsules 300mg, 30 Count

Nootropics Depot
87/100
Excellent
$1.33/day300mg/serving$39.99 (30 servings)

$39.99 ÷ 30 days at 300mg/day (1 serving × 300mg)

✓ Third-party testedIn-house and third-party CoA

Pick this if you weight published lot-level CoAs more than the Niagen trademark on the label; same molecule, more visible third-party paper trail

+Per-lot CoAs published openly, rare in the NR market
+300mg at the cleanest trial dose point
+Strong brand reputation for tight sourcing
Does not always label Niagen explicitly, so the licensing chain is less obvious than Tru Niagen or Thorne
30ct bottle runs out in a month
Dosing
24/25
Purity
23/25
Value
19/25
Transparency
21/25

Prices checked 2026-05-15. Cost shown is per clinically effective daily dose, not per pill.

06

NAD+ Cell Regenerator and Resveratrol Elite, 30 Capsules

Life Extension
84/100
Good
$1.27/day300mg/serving$38.00 (30 servings)

$38.00 ÷ 30 days at 300mg/day (1 serving × 300mg)

✓ Third-party testedThird-party tested

Reasonable if you were already planning to take resveratrol and quercetin alongside NR; otherwise pay for them separately so you can dose-adjust independently

+Genuine Niagen at the 300mg dose
+Bundles polyphenols people often stack anyway
+Life Extension's third-party testing on finished product
Bundling makes it hard to know what's doing what
Polyphenol stack has its own thin trial record
Higher per-day cost than plain Niagen at the same dose
Dosing
23/25
Purity
19/25
Value
19/25
Transparency
23/25

Prices checked 2026-05-15. Cost shown is per clinically effective daily dose, not per pill.

Best Value
07

Nicotinamide Riboside 300mg, 60 Capsules

Double Wood Supplements
82/100
Good
$0.50/day300mg/serving$29.95 (60 servings)

$29.95 ÷ 60 days at 300mg/day (1 serving × 300mg)

✓ Third-party testedThird-party tested (per brand)

Reasonable pick if you are NR-curious and not willing to pay the Niagen premium; the pharmacology is identical to the trial molecule but the sourcing paper trail is thinner

+Roughly 60% cheaper per day than Tru Niagen at the same 300mg dose
+Double Wood's third-party testing program
+60ct bottle covers a full Conze-style 8-week trial
Generic NR, not the Niagen material used in published trials
Per-lot CoA not as openly published as Nootropics Depot
Dosing
22/25
Purity
19/25
Value
22/25
Transparency
19/25

Prices checked 2026-05-15. Cost shown is per clinically effective daily dose, not per pill.

08

Elysium Basis NAD+ Supplement, 30 Servings

Elysium Health

81/100
Good
$1.67/day250mg/serving$50.00 (30 servings)

$50.00 ÷ 30 days at 250mg/day (1 serving × 250mg)

✓ Third-party testedThird-party tested

Elysium ran its own Basis trial (Dellinger 2017) showing NAD+ elevation; the marketing leans heavily on this single industry-funded study, which is a fair signal but not enough to justify the premium over plain Niagen

+Bundled NR plus pterostilbene with clean dosing labels
+Elysium has its own published trials on this combination
+Strong brand transparency on sourcing and testing
Pricier than equivalent plain Niagen by a wide margin
Trial record largely on the combination, not the head-to-head vs NR alone
NR dose at 250mg is below Conze's optimal data point
Dosing
22/25
Purity
19/25
Value
17/25
Transparency
23/25

Prices checked 2026-05-15. Cost shown is per clinically effective daily dose, not per pill.

09

Toniiq Nicotinamide Riboside 1000mg, 60 Capsules

Toniiq

79/100
Good
$0.67/day1000mg/serving$39.99 (30 servings)

$39.99 ÷ 60 days at ~503mg/day (0.5 servings × 1000mg)

✓ Third-party testedThird-party tested

The pick if you specifically want to mirror Martens or NADPARK's 1000mg/day protocol and the Niagen-branded SKUs at that dose feel overpriced

+Hits the 1000mg/day dose used in Martens and NADPARK at a budget price
+Stabilized NRHM formula claim and vegan capsule
+Strong per-mg value if you want the higher dose without the Niagen premium
Generic NR, not the Niagen used in the published trials
Toniiq is a newer entrant with thinner brand reputation than Thorne or Life Extension
Per-lot CoAs not published openly
Dosing
22/25
Purity
19/25
Value
20/25
Transparency
18/25

Prices checked 2026-05-15. Cost shown is per clinically effective daily dose, not per pill.

Full Comparison

Category
Tru Niagen 300mg, 90 Servings
Tru Niagen
Tru Niagen 300mg, 30 Servings
Tru Niagen
Thorne NiaCel 400, 60 Capsules
Thorne
Thorne NiaCel 250, 60 Capsules
Thorne
Nicotinamide Riboside Capsules 300mg, 30 Count
Nootropics Depot
NAD+ Cell Regenerator and Resveratrol Elite, 30 Capsules
Life Extension
Nicotinamide Riboside 300mg, 60 Capsules
Double Wood Supplements
Elysium Basis NAD+ Supplement, 30 Servings
Elysium Health
Toniiq Nicotinamide Riboside 1000mg, 60 Capsules
Toniiq
Brand Score93/100Winner92/10091/10089/10087/10084/10082/10081/10079/100
Dosing & Form25/25Winner25/2524/2524/2524/2523/2522/2522/2522/25
Purity22/2522/2524/25Winner22/2523/2519/2519/2519/2519/25
Value22/25Winner21/2519/2520/2519/2519/2522/2517/2520/25
Transparency24/25Winner24/2524/2523/2521/2523/2519/2523/2518/25
Cost/Day$1.10$1.33$1.25$0.80$1.33$1.27$0.50Winner$1.67$0.67
Dose/Serving300mg300mg415mg250mg300mg300mg300mg250mg1000mg
FormNiagen nicotinamide riboside chloride (capsule)Niagen nicotinamide riboside chloride (capsule)Niagen nicotinamide riboside chloride (capsule)Niagen nicotinamide riboside chloride (vegetarian capsule)Nicotinamide riboside chloride (capsule)Niagen NR plus trans-resveratrol, quercetin phytosome, fisetin (vegetarian capsule)Generic nicotinamide riboside (capsule)Nicotinamide riboside (NR-E) plus pterostilbene (capsule)Generic nicotinamide riboside (stabilized NRHM, vegan capsule)
Third-Party Tested✓ Yes✓ Yes✓ Yes✓ Yes✓ Yes✓ Yes✓ Yes✓ Yes✓ Yes
Proprietary BlendNoNoNoNoNoNoNoNoNo

Frequently Asked Questions

NR vs NMN — which one should I take?

NR. NMN was excluded from the US supplement market in late 2022 when the FDA accepted an investigational new drug application for it, which legally bars it from being sold as a dietary supplement. NR (Niagen) holds an accepted FDA New Dietary Ingredient notification, GRAS status, and is the form used in essentially every published human RCT in the NAD+ precursor space. NMN converts to NR before crossing into cells in many tissues anyway, so the practical difference is smaller than marketing suggests. The legal and evidence picture both favor NR.

What is Niagen and why does the form matter?

Niagen is ChromaDex's branded nicotinamide riboside chloride, the patented and clinically-trialed form of NR. It holds FDA NDI status, GRAS affirmation, and has been the test material in essentially every published human NR trial including Conze 2019, Martens 2018, Dollerup 2018, Remie 2020, and Brakedal 2022 NADPARK. Generic NR from cheaper Amazon brands is chemically the same molecule, but the trials behind the supplement category were all done on Niagen specifically. ChromaDex licenses Niagen to Tru Niagen, Thorne (NiaCel), Life Extension, Elysium (Basis), and dozens of other reputable brands. If you want the form with the evidence behind it, look for Niagen on the label.

Does NR actually slow aging or extend lifespan?

Not in any human trial that has tested it. NR raises NAD+, and NAD+ declines with age, so the marketing pitch is that restoring NAD+ should slow aging. The actual human trials have measured things like blood pressure, insulin sensitivity, muscle function, and cognitive scores. The biomarker (NAD+) goes up reliably. The functional outcomes mostly have not moved. Mouse lifespan data are inconsistent and short. Any claim that NR slows human aging or extends lifespan is an inference from biomarker shifts, not an outcome that has been demonstrated.

Is NR safe at the doses people take?

The published safety record is reassuring. Conze 2019 (8 weeks at 100-1000mg in 132 adults), Martens 2018 (6 weeks at 1000mg), Dollerup 2018 (12 weeks at 2000mg total daily), and Brakedal 2022 NADPARK (30 days at 1000mg in Parkinson's patients) all reported no serious adverse events and clean safety blood work. NR-SAFE in 2023 extended the safety record to higher doses in Parkinson's. The only common side effects are mild GI upset and occasional headache. People with active cancer should talk to their oncologist; the rest of the population has a benign safety profile to work with.

How long until I feel anything from NR?

Probably nothing dramatic, ever. NAD+ levels start rising within days and plateau within roughly 2 weeks at any given dose. Subjective effects are not consistently reported in trials. People who report energy or wellbeing shifts on NR are likely seeing placebo effects, regression to the mean, or genuine but small individual responses that the population-level trials cannot detect. If you do not feel anything in 4-8 weeks at 300-1000mg, that matches the population data; the supplement may still be raising your NAD+ without any felt experience.

Is NR worth the money?

Depends on what you want from it. At roughly $1.00-1.50 per day for genuine Niagen at the 300mg dose, NR is one of the more expensive supplements people take regularly. If you want the cleanest, best-studied NAD+ precursor and you are content with raising the biomarker, it is reasonable. If you want measurable energy, body composition, or anti-aging effects, the trial record does not support that expectation and you are essentially paying for a hope, not a result. Generic NR runs cheaper but was not the form tested in the studies that built the category's reputation.

Can I stack NR with other longevity supplements?

NR is commonly stacked with pterostilbene (Elysium Basis combines them), resveratrol (Life Extension's combo SKU), and various other compounds. None of those combinations have been tested in well-controlled human trials versus NR alone, so the combined-effect claims are theoretical. NR is well-tolerated and unlikely to interact badly with most other supplements, but adding more pills does not multiply the underlying evidence. If you choose to stack, do it because the individual ingredients have their own evidence, not because of a synergy claim.

Sources

  1. Martens CR, Denman BA, Mazzo MR, et al. Chronic nicotinamide riboside supplementation is well-tolerated and elevates NAD+ in healthy middle-aged and older adults. Nat Commun. 2018;9(1):1286.
  2. Conze D, Brenner C, Kruger CL. Safety and metabolism of long-term administration of NIAGEN (nicotinamide riboside chloride) in a randomized, double-blind, placebo-controlled clinical trial of healthy overweight adults. Sci Rep. 2019;9(1):9772.
  3. Dollerup OL, Christensen B, Svart M, et al. A randomized placebo-controlled clinical trial of nicotinamide riboside in obese men: safety, insulin-sensitivity, and lipid-mobilizing effects. Am J Clin Nutr. 2018;108(2):343-353.
  4. Remie CME, Roumans KHM, Moonen MPB, et al. Nicotinamide riboside supplementation alters body composition and skeletal muscle acetylcarnitine concentrations in healthy obese humans. Am J Clin Nutr. 2020;112(2):413-426.
  5. Brakedal B, Dolle C, Riemer F, et al. The NADPARK study: a randomized phase I trial of nicotinamide riboside supplementation in Parkinson's disease. Cell Metab. 2022;34(3):396-407.e6.
  6. Trammell SAJ, Schmidt MS, Weidemann BJ, et al. Nicotinamide riboside is uniquely and orally bioavailable in mice and humans. Nat Commun. 2016;7:12948.
  7. Elhassan YS, Kluckova K, Fletcher RS, et al. Nicotinamide riboside augments the aged human skeletal muscle NAD+ metabolome and induces transcriptomic and anti-inflammatory signatures. Cell Rep. 2019;28(7):1717-1728.e6.
  8. Dolopikou CF, Kourtzidis IA, Margaritelis NV, et al. Acute nicotinamide riboside supplementation improves redox homeostasis and exercise performance in old individuals: a double-blind cross-over study. Eur J Nutr. 2020;59(2):505-515.
  9. Mehmel M, Jovanovic N, Spitz U. Nicotinamide riboside - the current state of research and therapeutic uses. Nutrients. 2020;12(6):1616.
  10. Stocks B, Ashcroft SP, Joanisse S, et al. Nicotinamide riboside supplementation does not alter whole-body or skeletal muscle metabolic responses to a single bout of endurance exercise. J Physiol. 2021;599(5):1513-1531.
  11. Brakedal B, Toker L, Haugarvoll K, Tzoulis C. A nationwide study of the incidence, prevalence and mortality of Parkinson's disease in the Norwegian population (NR-SAFE high-dose safety trial). Nat Commun. 2023;14(1):7842.

FDA Disclaimer: These statements have not been evaluated by the Food and Drug Administration. The products discussed on this page are not intended to diagnose, treat, cure, or prevent any disease. Always consult with a qualified healthcare professional before starting any supplement regimen.