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Verified by IngredientMD/Thorne/Basic Nutrients 2/Day
VERIFIED BYingredientMD

Basic Nutrients 2/Day.

Strong evidence, strong doseThorne, verified Oct 2026Formula verified. Independently reviewed.Independent review. Not commissioned by Thorne.

Vitamin C is the lead active here, studied most for iron status. 20 human studies on Vitamin C back this formula, each one cited. Each serving carries 1.05 mg of Vitamin A, inside the range the published research used. Who it fits: skews toward women, adults.

Clinically dosedFull label disclosure
9Active ingredientsWell studiedResearch base98Human studies
Basic Nutrients 2/DayVerified by IngredientMD
ThorneIngredientMD
The verdict
Strong evidence, strong dose
For Skews toward women, adults.
How we verify

The brand submits the formula. We read the supplement facts panel and weigh dose, form and synergy against the clinical evidence. Labs test. IngredientMD verifies. The fee pays for review time, never for the outcome.

The formula
Vitamin A: Filling everyday nutrient gapsExtensively studied
Vitamin C: Iron statusKey driver
Vitamin D3: Filling everyday nutrient gapsExtensively studied
Vitamin E: Filling everyday nutrient gapsWell studied
Vitamin K: Filling everyday nutrient gapsExtensively studied
Thiamin: Filling everyday nutrient gapsExtensively studied
Riboflavin: Filling everyday nutrient gapsExtensively studied
Niacin: Filling everyday nutrient gapsWell studied
Vitamin B6: Filling everyday nutrient gapsSupporting role

How we read this product

Source: Supplement facts
Supplement Facts panel for Basic Nutrients 2/Day
  1. 01
    We read the label.

    The panel on the left is the one we evaluated, line by line.

  2. 02
    Every active, separately.

    All 9 actives checked against the clinical evidence: dose, form, and what the research actually shows.

  3. 03
    Then the formula as a whole.

    Doses, ratios, and how the ingredients work together. That assessment is the verdict above: "Strong evidence, strong dose".

  4. 04
    Earned, not bought.

    The verdict is public and identical whether or not a brand pays. A formula that does not clear the bar gets nothing.

Read by the engine against 2.1 million data points from clinical trials, PubMed and more than a hundred vetted sources. No individual reviewer is named or implied.

The receipts

Well studied
Research base
98
Human studies
250 mg
Vitamin C
1.05 mg
Vitamin A
1 mg per serving clears the studied 700 mcg minimum
Vitamin A, NIH ODS + Ross 2006 review
250 mg per serving sits inside the studied 200 mg-500 mg range
Vitamin C, Levine 1996 pharmacokinetics + NIH ODS
400 mcg per serving clears the studied 90 mcg minimum
Vitamin K, NIH ODS
50 mg per serving sits inside the studied 1 mg-50 mg range
Thiamin, NIH ODS + Lonsdale 2006 review

Cross-checked against 2,439 documented interactions for these actives.

Read the evidenceVitamin A, the evidence →Vitamin C, the evidence →Vitamin D3, the evidence →Vitamin E, the evidence →Vitamin K, the evidence →Thiamin, the evidence →

Inside the formula

Vitamin A
Filling everyday nutrient gaps
Studied 700 mcg to 3 mg a day
Extensively studied
Vitamin C
20 studies
Iron status
Studied 200 mg to 1 g a day
Key driver
Vitamin D3
20 studies
Filling everyday nutrient gaps
Extensively studied
Vitamin E
15 studies
Filling everyday nutrient gaps
Well studied
Vitamin K
11 studies
Filling everyday nutrient gaps
Studied 90 mcg to 500 mcg a day
Extensively studied
Thiamin
11 studies
Filling everyday nutrient gaps
Extensively studied
Riboflavin
10 studies
Filling everyday nutrient gaps
Studied 1.3 mg to 100 mg a day
Extensively studied
Niacin
Filling everyday nutrient gaps
Studied 20 mg to 500 mg a day
Well studied
Vitamin B6
Filling everyday nutrient gaps
Supporting role
In context

The gap this formula speaks to.

Public health figures the engine matched to this formula's ingredients. Reported by their source, cited and dated, never written by the brand.

45 more
The people it speaks to

60.2% of US adults aged 20 and over

took a dietary supplement in the past 30 days, and 38.7% took two or more, in the 2021 to 2023 National Health and Nutrition Examination Survey.

CDC National Center for Health Statistics, 2026
Daily use

59 to 66 days

was the median time it took adults to make a new daily health habit automatic across the studies a 2024 review pooled, with individuals ranging from 4 to 335 days.

Systematic review and meta-analysis, 2024
Vitamin K

Systematic review, 2024

Across trials in middle-aged and older adults, vitamin K supplementation raised the active carboxylated form of the bone protein osteocalcin and lowered its inactive form, reflecting greater osteocalcin activation.

Bone & Joint Research
Vitamin D3

Meta-analysis, 2024

Across 10 trials in 318 athletes, vitamin D3 raised blood vitamin D by about 14.8 nmol/L and hinted at better muscle strength, though few trials leave that uncertain.

Frontiers in Nutrition
Vitamin C

Meta-analysis, 2011

Across 13 trials, about 500 mg of vitamin C daily lowered blood uric acid by roughly 0.35 mg/dL.

The paper
Vitamin C

Randomised trial, 2026

In repeated single-person trials, vitamin C raised blood levels by 20.6 micromol/L and lowered two stress markers, with day-to-day swings bigger than differences between people.

Free Radical Biology and Medicine
Niacin

Systematic review and meta-analysis, 2016

Across 14 placebo-controlled trials totaling about 9,000 people, extended-release niacin lowered blood lipoprotein(a) by about 23 percent.

Metabolism
Niacin

Systematic review and meta-analysis, 2014

Across 7 trials of 441 people, niacin improved a blood vessel dilation test by about 2 percentage points.

Vascular Medicine
Vitamin E

Meta-analysis, 2022

Across 8 trials in 1,002 women, vitamin E taken by mouth reduced reported menstrual cramp pain compared with placebo, with the clearest effect in the first month.

Clinical Nutrition ESPEN
Vitamin C

Meta-analysis, 2014

Across 44 trials, vitamin C improved how well the blood vessel lining widens, a moderate effect of 0.50, larger at higher doses.

The paper
Ashor et al., 2014PMID 24792921
Vitamin E

Randomised trial, 2023

In 160 postmenopausal women with long-standing sleep difficulty, one month of vitamin E brought the median sleep questionnaire score to 6, versus 9 on placebo, where lower means better sleep.

Nutrients
Niacin

Meta-analysis, 2020

Across eight trials in 2,110 adults with high blood sugar, niacin shifted cholesterol, triglycerides, LDL and HDL by 0.28 to 0.42, with no detected change in blood sugar or HbA1c.

Medicine
Vitamin D3

Randomised trial, 2025

Vitamin D3 supplementation changed the inflammatory protein CHI3L1 and oxidative stress markers in adults with a chronic demyelinating condition. These are markers, not clinical outcomes.

Neuropsychopharmacology Reports
Vitamin K

Meta-analysis, 2022

Pooling 16 randomized trials in 6,425 postmenopausal women, vitamin K2 supplementation improved lumbar spine bone mineral density and lowered undercarboxylated osteocalcin.

Frontiers in Public Health
Vitamin K

Randomised trial, 2015

In 244 healthy postmenopausal women, three years of 180 mcg per day menaquinone-7 reduced carotid-femoral pulse wave velocity, a marker of arterial stiffness, and cut inactive matrix Gla-protein by about 50 percent versus placebo.

Thrombosis and Haemostasis
Vitamin D3

Meta-analysis, 2024

Across 20 studies, daily vitamin D3 raised blood vitamin D levels by about 10.4 nmol/L more than the same dose of vitamin D2, roughly 40 percent more.

Advances in Nutrition
Riboflavin

Systematic review, 2026

The review found that reported responsiveness to riboflavin across inherited disorders of metabolism is uneven and rests largely on small series, so the strength of evidence varies by the specific condition.

Journal of Inherited Metabolic Disease
Vitamin C

Meta-analysis, 2012

Pooling 29 randomized trials, vitamin C at a median of 500 mg a day lowered systolic blood pressure by about 3.8 mmHg and diastolic by about 1.5 mmHg over a median of eight weeks.

American Journal of Clinical Nutrition
Vitamin E

Meta-analysis, 2025

Across 21 trials, vitamin E lowered oxidized LDL and lengthened the time before LDL starts to oxidize, by about 20.45 units, both lab markers of oxidation.

European Journal of Pharmacology
Riboflavin

Randomised trial, 2013

In adults with elevated blood pressure carrying the MTHFR 677TT genotype, riboflavin 1.6 mg per day lowered systolic blood pressure by about 5.6 mmHg versus placebo over 16 weeks.

The paper
Wilson et al., 2013PMID 23608654
Thiamin

Cohort study, 2026

Reports an association between dietary thiamin, riboflavin and niacin intake and elevated blood pressure and pulse pressure. An association in intake data, not a demonstration of cause.

Medicine
Riboflavin

Meta-analysis, 2024

In a dose-response meta-analysis of randomised trials, riboflavin was associated with about 1.3 fewer severe recurring headache attacks per month compared with control.

Neurological Sciences
Vitamin E

Meta-analysis, 2023

Across 12 trials in 794 adults with high liver fat, at least 400 IU of vitamin E daily lowered two liver enzyme markers by 7 to 10 and 5 units.

Nutrients
Vitamin D3

Meta-analysis, 2014

Across 23 trials of 4,082 adults, vitamin D raised bone mineral density at the femoral neck by about 0.8%, with no measurable change at the spine, hip, or other sites.

Lancet
Vitamin K

Meta-analysis, 2024

Pooling randomised trials, vitamin K supplementation showed no consistent improvement in circulating markers such as blood lipids and blood pressure.

Journal of nutritional science
Thiamin

Randomised trial, 2019

Thiamin supplementation did not improve left ventricular ejection fraction in the participants studied. This is a failure to detect a difference in an imaging marker, not evidence that no difference exists.

The American Journal of Clinical Nutrition
Vitamin A

Meta-analysis, 2022

Across 19 trials of about 1.2 million children in vitamin A deficient settings, supplementation lowered all-cause mortality by 12 percent (risk ratio 0.88), rated high-certainty evidence.

Cochrane Database of Systematic Reviews
Riboflavin

Meta-analysis, 2025

A nutrition-status analysis in children included thiamin among the micronutrients measured, reporting intake and status data rather than a result of giving supplements.

Journal of Human Nutrition and Dietetics
Thiamin

Randomised trial, 2026

Thiamin supplementation improved the thiamin pyrophosphate effect, a blood marker of thiamin adequacy, in children whose levels were low.

Scientific reports
Vitamin A

Randomised trial, 1998

Weekly vitamin A lowered the incidence of night blindness in pregnant women from 10.7 percent to 6.7 percent, and by about 67 percent among those who took nearly all of their doses.

Journal of Nutrition
Vitamin E

Meta-analysis, 2026

Pooling the available trials, adjuvant vitamin E alongside varicocele surgery was associated with better post-operative semen parameters, which are laboratory markers of sperm quality and not fertility outcomes.

Archivio Italiano di Urologia e Andrologia
Vitamin A

Randomised trial, 2026

In 306 newborns given 50,000 IU vitamin A within 48 hours of birth, the delayed skin immune response to BCG improved modestly in heavier babies, while antibody responses to polio, tetanus and hepatitis B vaccines showed no detectable change.

Vaccine
Riboflavin

Meta-analysis, 2021

Pooling nine controlled trials in 673 people, vitamin B2 at 400 mg per day for three months lowered the frequency, days, duration and pain score of severe recurring headache attacks.

Nutritional Neuroscience
Riboflavin

Randomised trial, 2023

Two weeks of 50 or 100 mg per day of riboflavin raised measured gut butyrate production and increased microbial network connectivity, without shifting overall gut bacterial composition or Faecalibacterium prausnitzii abundance.

Antioxidants and Redox Signaling

Population figures from public health data. Context for the category, not a statement about any individual and not a claim about this product.

What this formula earned

Every one of these is a fact the engine could ground.

Each line below was derived from this formula's own record at the time of verification. Nothing here was written by the brand, and nothing can be added that the evidence does not carry.

  • Studied in people20 human studies on Vitamin C back this formula, each one cited.
  • A mechanism that is settledHow Vitamin A and Vitamin C work is settled pharmacology.
  • Studied together, not just separatelyVitamin A and Vitamin E have been studied together, not only separately.
  • Recent work on the recordThe most recent study on this record was published in 2026.
  • Serving amount inside the studied rangeEach serving carries 1.05 mg of Vitamin A, inside the range the published research used.
  • A stated daily maintenance amountVitamin A is here at a daily maintenance amount, which is what a daily supplement is for.
  • Why this formatIt is a capsule, so the amount per serving is fixed and travels without measuring.
  • The exact form, describedThe label names its forms exactly: Retinyl palmitate, Ascorbic acid, Vitamin D3 in a carrier oil, lanolin-derived. The record says what each one is and what it suits.
  • Full label disclosureEvery ingredient on this label carries its own declared amount.
  • Where it comes from and how it is madeVitamin A is made by more than one route.
  • Positions this formula already qualifies forThis formula already qualifies for positions beyond the one it is sold into, on the evidence it carries.
  • A position nobody is holding yetSome of those positions are ones almost nobody is selling to yet.
  • Interaction screen on the recordEvery active on this label was screened against the interaction record, and the screen is published with it.
How much it moves the numbers

The size of the effect, in plain numbers.

Where a trial measured an actual number, we show it next to the claim. It is the average across the trials, never a promise about one person.

Vitamin Crisk of developing a cold
Average change in the trials

About 52 percent lower risk of developing a cold, in trials of people undergoing brief periods of severe physical exertion.

Measured in
marathon runners, skiers and soldiers on subarctic exercises
Confidence interval
risk ratio 0.48, 95% CI 0.35 to 0.64

Read at the source. The magnitude sits beside the same trial the claim already cites. It describes what the trials measured, never what any one person will feel.

What the trials show

What the trials show about timing.

Time-to-effect windows the engine read from the trial record. Each is a window a named study measured, cited and dated, never written by the brand.

  • Vitamin Cwithin 24 hours of a single doseMeasured within a day

    In a randomised crossover trial, 12 healthy adults consumed 101.7 mg of vitamin C as a powder, as raw fruits and vegetables, or as juice, and plasma vitamin C rose after every intake form, with plasma and urinary levels tracked over the 24 hours following the single dose.

    Strong
  • Vitamin D3about 3 months of daily useBuilds with daily use

    In the trial record, blood vitamin D rises for about 3 months of daily vitamin D3 and then holds at a plateau, near 69 nmol/L at 1,000 IU a day, from a starting level near 41 nmol/L.

    Early
  • Vitamin Eabsorbed slowly, tracked over 72 hoursMeasured within a day

    In a 3-phase crossover using two deuterium-labelled forms of alpha-tocopherol, healthy women absorbed about 55 percent of an oral dose taken with a 40 percent fat meal and about 64 percent with a fat-free meal, with samples tracked over 72 hours. The authors conclude absorption is not limited by absent fat or fasting, and that vitamin E leaves the intestine by a prolonged process.

    Promising
  • Vitamin Kabout four weeks of daily useBuilds with daily use

    A double-blind randomised dose-finding trial gave 60 postmenopausal women aged 50 to 69 either 0, 50, 100 or 200 micrograms of menaquinone-7 daily for four weeks on a controlled diet. The ratio of carboxylated to undercarboxylated osteocalcin rose dose dependently, with significant differences from the 0 microgram group at 100 and 200 micrograms. A companion 12-week trial in 120 people aged 20 to 69 confirmed the change at 100 micrograms daily. Both studies were run by authors affiliated with the R and D division of J-Oil Mills. An independent 8-week double-blind trial in 55 healthy prepubertal children found the same direction at 45 micrograms daily. What was measured is a blood marker of vitamin K status, not bone density and not a sensation.

    Promising
  • Vitamin Kthree years of daily use, with measurements at one, two and three yearsBuilds with daily use

    A double-blind randomised trial gave 244 healthy postmenopausal women either placebo or 180 micrograms of menaquinone-7 daily for three years, with bone mineral density measured by DXA at baseline and after each year. Menaquinone-7 decreased the age-related decline in bone mineral content and bone mineral density at the lumbar spine and femoral neck, but not at the total hip. The effect is a slowed decline rather than a gain, and the trial ran three years rather than weeks.

    Promising
  • Thiaminabout 18 to 30 days of restricted intakeBuilds with daily use

    In the controlled depletion study the EFSA reference opinion reviews, restricting thiamin intake to 0.009 to 0.015 mg/MJ for 30 days brought urinary free thiamin excretion from a mean of 0.283 mg/24 h down to undetectable levels by day 18 of the depletion period.

    Promising
3 more
  • Thiaminabout 1 week of renewed intakeBuilds with daily use

    In the same depletion and repletion record the EFSA reference opinion reviews, erythrocyte transketolase activity fell progressively to about 75% of baseline during the 30-day depletion period and returned to its baseline value after 1 week of thiamin repletion.

    Promising
  • Riboflavinabout 8 weeks of daily intakeBuilds with daily use

    In an intervention the EFSA reference opinion reviews, adults whose baseline riboflavin intake and status were unknown received 5 mg/day of riboflavin for 8 weeks, and haemoglobin concentration, haematocrit and erythrocyte count all rose significantly over that period.

    Early
  • Vitamin B6about 20 to 40 days to clear after stoppingBuilds with daily use

    An expert consensus on vitamin B6 use, developed by a six-member Delphi panel with a structured evidence-quality assessment, calculated from pharmacokinetic parameters that complete clearance of vitamin B6 from the body takes a washout period of about 20 to 40 days after intake stops.

    Early

Windows measured in the cited trials. Context for how the active behaves over time, not a statement about any individual and not a claim about this product.

General timing

How each ingredient usually behaves over time.

9 ingredients, from each one's own page.

  • Vitamin AWeeks, not days

    Weeks to months. Liver stores buffer intake, so vitamin A status moves slowly and shows up on a blood panel rather than as a sensation.

    Its own page, the plain answer on timing

  • Vitamin CWithin hours

    Blood levels rise within hours and tissue pools fill over days. Collagen-linked changes in skin and gums build over weeks and show as tissue quality, not as a sensation.

    Its own page, the plain answer on timing

  • Vitamin D3About six to twelve weeks

    25-hydroxyvitamin D climbs over roughly six to twelve weeks of daily dosing before it plateaus. It's a blood level you watch rather than a feeling.

    Its own page, the plain answer on timing

  • Vitamin EWeeks, not days

    Plasma alpha-tocopherol climbs within days of daily intake, and anything you'd notice in skin condition is a slow change across a couple of months.

    Its own page, the plain answer on timing

  • Vitamin KWithin days

    Clotting factor carboxylation responds within days. The bone marker undercarboxylated osteocalcin shifts across roughly four to twelve weeks, so this shows up on a panel.

    Its own page, the plain answer on timing

  • Thiamin

    There is no onset to time in the usual sense. Status markers such as erythrocyte transketolase activity move across weeks, and that is where the change is read.

    Its own page, the plain answer on timing

3 more

How each ingredient usually behaves over time, from its own page on IngredientMD. General timing for the ingredient, not a measurement of this product.

Chemical form

The same ingredient, carried differently.

What each form is, and where it fits in a formula. Measured findings carry the study that reported them.

  • Cholecalciferol (vitamin D3)

    The animal-sourced form of vitamin D, made in skin under UVB light and produced commercially from lanolin. Fat-soluble, so it travels with dietary fat and is stored in body fat.

    Fits
    Raising and holding vitamin D status, and the form most supplement trials use.
    Trade-off
    Being fat-soluble it accumulates with sustained high dosing, so intakes are set against the tolerable upper level rather than topped up freely.

    In a 12-week double-blind randomised controlled trial in 108 young women in urban Bangalore, most of whom began vitamin D-deficient, daily vitamin D3 at 400, 600 or 800 IU in a fortified wafer raised serum 25-hydroxyvitamin D, parathyroid hormone fell over time, and effects on bone-turnover markers were modest and not dose specific. The 800 IU dose brought 65 percent of participants to sufficiency.

  • Riboflavin

    The free vitamin B2 molecule, an isoalloxazine ring joined to a ribitol sugar chain, supplied as the unmodified crystalline compound with no added salt or phosphate group.

    Fits
    It is the form most panels list simply as riboflavin or vitamin B2.
    Trade-off
    It is intensely yellow and only sparingly water soluble, so it can tint a finished product and tends to resist dissolving cleanly in a liquid or a fast-melt format.
  • Nicotinic acid

    The free-acid form of vitamin B3, pyridine-3-carboxylic acid. It is the reference form of niacin, a small water-soluble molecule carrying a bare carboxylic acid group on the pyridine ring.

    Fits
    The long-standing reference form for meeting a vitamin B3 requirement.
    Trade-off
    This is the form behind the familiar warm, tingling skin flush that many people notice soon after a larger dose, a recognized property of the free acid that leads some formulators to reach for an amide or ester instead.

Descriptions of the form itself, read from the cited studies. Not a comparison between products and not a statement about any individual.

Format

Capsule

It is a capsule, so the amount per serving is fixed and travels without measuring.

Best forMost standard doses, and anywhere a short, clean label is the point.

Questions shoppers ask

Is Basic Nutrients 2/Day independently verified?
Yes. IngredientMD reviewed this formula independently and verified it in Oct 2026. The verdict is earned, not bought: brands can't edit or purchase it.
What's in Basic Nutrients 2/Day?
Basic Nutrients 2/Day is built on Vitamin A, Vitamin C, Vitamin D3, Vitamin E, Vitamin K, Thiamin, and more. Each ingredient links to its own evidence page on IngredientMD.
Were ingredient interactions checked?
Yes. The combination was screened against 2,439 documented interactions for these actives in IngredientMD's interaction database.
Who is IngredientMD?
IngredientMD is an independent supplement-science platform. We analyze ingredients and formulas against clinical research, and we verify products only when they clear our bar. Labs run the tests. We review the results.
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These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. This record is not medical advice. Always consult your healthcare provider before starting any supplement regimen.

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