Day Pack · Immunity + Energy · The Science

The science of switching on.

Thirteen ingredients. Clearly stated doses. Every number on this page has a paper behind it.

RCTA randomised trial against placebo, where neither side knows who got what.
Absorption studyMeasures how much of a dose the body takes in.
ObservationalMeasures people as they are, without giving them anything.
MechanismHow an ingredient works in the body.

02 · The handover

Every morning your body hands over the other way, from rest to alert.

waking Illustration only, not measured data ASLEEP · REST AWAKE · ALERT

03

Switched on, not wired

Your drive to sleep grows every hour you're awake, and a chemical called adenosine helps you feel it.1 Caffeine blocks adenosine. The tiredness is still there. You just feel it less.1

Day Pack works on the other side. It supports the energy your body makes, with no caffeine.

Illustration of a person standing, in translucent glass, eyes open. 1, the gut glowing in the abdomen. 2, small amber points of energy through the chest. 3, a nerve network in the head. 4, the neck and shoulders.
Illustration, not anatomy to scale or a measurement.
  1. 1
    GutShowing up starts in your gut.

    Your gut lining holds more antibody-producing cells than anywhere else in your body.4 Ten strains, 10 billion CFU, help promote healthy gut flora. Vitamins C and D3 help enhance immune system function.

  2. 2
    EnergyB vitamins support energy production.

    Most of Day Pack's actives play a part in energy metabolism.

  3. 3
    MindZinc supports mental function.

    B vitamins support your nervous system, and vitamin B5 contributes to normal mental performance.

  4. 4
    BodyVitamin D supports muscle function.

    Vitamins D3 and K2 support bone health.

  5. Switched on0 mg caffeine.

    Switched on, not wired.

RCT

Caffeine keeps working after you stop noticing.

In a placebo-controlled sleep study, 400 mg of caffeine, about two to three 355 ml cups at once, cut deep sleep by about 21 minutes even when taken 12 hours before bed, and people didn't rate their sleep any worse. 100 mg, under one cup, changed nothing measurable at any time.2 3

Dose
12 h before bed11am
8 h before bed3pm
4 h before bed7pm
100 mgunder 1 cup
No change
No change
No change
400 mg2 to 3 cups
−21 mindeep sleep
+29 minawake at night
−51 mintotal sleep
Rated their sleep worse?
No
No
Yes34% worse
  • 12 h before bed · 11am100 mg: no change400 mg: −21 min deep sleepRated their sleep worse? No
  • 8 h before bed · 3pm100 mg: no change400 mg: +29 min awake at nightRated their sleep worse? No
  • 4 h before bed · 7pm100 mg: no change400 mg: −51 min total sleepRated their sleep worse? Yes, 34% worse
Design
Placebo-controlled, single doses
People
23 healthy men, aged about 25
Measure
Sleep measured at home
Timing
Clock times assume an 11pm bedtime

04

What you may notice, and what works quietly

Day Pack has no stimulants, so it won't feel like a coffee. If you notice a difference, expect it over weeks, not within the hour.

RCT B-complex with 500 mg vitamin C · 33 days −10%

Self-rated mental tiredness during demanding tasks fell 10%, while placebo was unchanged. Self-rated vigour rose more than on placebo.5

Formula−10%
Placebo0%
Less tiredMore
Design
Randomised, double-blind, placebo-controlled
People
215 working men aged 30 to 55
Formula
A B-complex formula with the same 500 mg of vitamin C, not Day Pack
Length
33 days
Measure
Self-rated mental tiredness during demanding tasks
Mechanism The work you don't feel ≈1%

The rest works quietly. You won't feel your immune system, your bones or the bacteria in your gut, just as you don't feel the roughly 1% of your cells your body replaces every day.6 7 That work happens every day, so Day Pack is built for every morning.

One dot is about 1% of your cells. Roughly 330 billion of about 30 trillion, every day.6 7

RCT Vitamin K2 (MK-7) · 100 mcg a day, the same as Day Pack

A daily habit, not a course.

In a 12-week double-blind, placebo-controlled study at 100 mcg a day, the same as Day Pack, blood MK-7 nearly tripled by week 4 and stayed up while people kept taking it. Four weeks after they stopped, it was back where it started. Markers of osteocalcin activation also improved against placebo while people took it.8

TAKING 100 MCG A DAY Stopped 01234 Wk 0Wk 4Wk 8Wk 12Wk 16 ng/mL 0.952.693.094.291.40 placebo
Week 4Nearly 3× the starting level
Weeks 8 to 12Held while taking it
Week 16Back to baseline 4 weeks after stopping

Blood MK-7, mean ng/mL. 120 healthy Japanese adults aged 20 to 69.8

Design
Randomised, double-blind, placebo-controlled
People
120 healthy Japanese adults aged 20 to 69
Dose
100 mcg a day
Length
12 weeks, then 4 weeks off
Measure
Blood MK-7 and markers of osteocalcin activation

Vitamins D3 and K2 support bone health.

Study figures describe the individual ingredients at the doses in Day Pack, not Day Pack itself.

Consult a healthcare professional prior to use if you are taking a blood thinner such as warfarin.

05

Ingredient by ingredient, and why each dose

Your small intestine absorbs most of the nutrients in your food. The vitamins and zinc below are absorbed there too.9

Every dose in Day Pack has a reason behind it: the dose a trial used, or about as much as the body takes up at once. Where a dose has no study behind it, this page says so. Two doses, D3 and zinc, also sit at the ceiling Singapore sets for health supplements. That is a safety limit, not a reason on its own, so it comes last.

IngredientDoseWhat it doesWhy this dose
B vitamins, all eightSee belowEnergy production, nervous system, mental performanceTrial doses or a day's requirement. Three doses have no trial, and we say so.
Vitamin C500 mgImmune function, energy metabolismBlood levels stop rising at about 400 mg a day. The dose the trials used.
Vitamin D325 mcg · 1,000 IUImmune function, muscle, boneRaises blood vitamin D steadily. Singapore's maximum, a safety limit.
Vitamin K2 (MK-7)100 mcgBone healthThe lowest dose that made a measurable difference.
Zinc15 mgMental function, energy metabolism, boneRaises blood zinc, well short of affecting copper. Singapore's maximum, a safety limit.
Probiotics10 billion CFUHealthy gut floraHealth Canada's gut-flora threshold is 1 billion, held through shelf life. Ours is 10 billion at manufacture.

B vitamins, all eight

For energy and the mind

All 8

B1 · B2 · B3 · B5 · B6 · folic acid · B12 · biotin

What they do

B vitamins support energy production. B1, B2, B3, B5, B6, B12 and biotin help in energy metabolism.

Vitamin B5 contributes to normal mental performance. Biotin, folic acid, B1, B3, B6 and B12 contribute to normal psychological function. B vitamins support your nervous system.

One or more B vitamins take part in every step of turning food into energy inside your cells, and the eight work closely together.10 So Day Pack carries all eight.

Why these amounts

B183 mgTrial at 50 mg
B215 mgAbsorption limit
B315 mgA day's need · no trial
B5100 mgNo trial at this dose
B630 mgBetween trial doses
Folic acid750 mcgTrial at this dose
B1250 mcgAbsorption
Biotin50 mcgA day's need · no trial
Triala human trial behind the dose Absorptionhow much the body takes up No trialwe say so
The reasoning behind each dose

B1 83 mg. In a 2-month placebo-controlled trial of 120 young women, 50 mg of thiamine a day, below Day Pack's dose, was followed by faster reaction times, and the women whose thiamine status improved most described themselves as more clearheaded and energetic.15

B2 15 mg. The gut takes up at most about 27 mg of riboflavin from a single dose.16 15 mg stays inside that limit, so one morning dose is not wasted.

B3 15 mg. About a day's requirement, as nicotinamide, the form that does not cause flushing. No trial has tested this dose on its own. It is there to complete the eight.

B5 100 mg. No trial has tested pantothenic acid on its own at this dose in healthy adults. 100 mg sits above the 23 to 69 mg used in the B-complex trials, and no tolerable upper limit has been set for pantothenic acid.

B6 30 mg. In a 3-month placebo-controlled study of 76 healthy men aged 70 to 79, 20 mg a day modestly improved memory storage.17 In a 35-day trial of 211 healthy women, 75 mg had a small effect on some memory measures and none on mood.18 Day Pack's 30 mg sits between the two.

Folic acid 750 mcg. The same trial of 211 women tested 750 mcg of folate a day for 35 days, the dose in Day Pack, and found small gains on some memory measures.18

B12 50 mcg. The gut's active route for B12 takes up only about 1.5 to 2 mcg from any one dose. Beyond that, about 1% is absorbed passively.19 From 50 mcg that adds up to roughly a day's requirement of 2.4 mcg, even if the active route is already full. In a 4-week placebo-controlled trial of 58 young adults, a B-complex formula with 10 mcg of B12 raised blood B12 by about a fifth while placebo did not.20

Biotin 50 mcg. A little over a day's requirement of 30 mcg. No trial has tested this dose on its own.

The eight together

In a 33-day placebo-controlled trial of 215 working men aged 30 to 55, a B-complex formula with the same 500 mg of vitamin C raised self-rated vigour and lowered self-rated mental tiredness during demanding tasks, compared with placebo.5 That formula carried less B1, B5, B6, B12 and folic acid than Day Pack, more B3 and biotin, and the same vitamin C.

Limits

Not every trial finds it: a 4-week study of the same formula in 58 younger adults saw no change in vigour or fatigue.20

Vitamin C

For immunity and energy

500 mg

What it does

Plays a part in energy metabolism and contributes to normal psychological function. Helps enhance immune system function. Contributes to normal collagen formation for the normal function of skin. Contributes to the protection of cells from oxidative stress.

Your body can't make vitamin C and keeps only a small reserve.11

Why 500 mg

In healthy young women, blood and white-cell vitamin C stop rising at about 400 mg a day. Above that, the kidneys clear the extra.21 A 200 mg dose is absorbed completely; at 500 mg, between 60 and 75% is.22

200 mg dose 100% 500 mg dose 60–75% Share absorbed from one dose. From 500 mg, about 300 to 375 mg.

So 500 mg holds the ceiling from one morning dose, and it is the dose the trials used.

The trial at 500 mg

In a 2-month placebo-controlled trial of 184 healthy non-smokers, 500 mg a day lowered a urine marker of oxidative damage to fats.23 The B-complex trial in section 04 used 500 mg too.5

Vitamin D3

For immunity, muscle and bone

25 mcg

1,000 IU

What it does

Supports muscle function. Helps enhance immune system function and supports bone health. Helps your body absorb and use the calcium from your food.

1 in 3indoor workers in Singapore had blood vitamin D below 50 nmol/L12213 indoor workers at four Singapore workplaces. Office workers were about twice as likely to be low as control-room staff.

Why 1,000 IU

50 75 3090 blood vitamin D, nmol/L Started low3 months 4169 Started well supplied60 days 7583
The three trials

In healthy adults it raises blood vitamin D steadily rather than sharply: about 0.7 nmol/L for every microgram taken daily, in a 20-week winter trial of 67 men24; from 41 to 69 nmol/L over 3 months in a Toronto trial of adults who started low25; and from 75 to 83 nmol/L over 60 days in 72 young adults who started well supplied, where the share above 75 nmol/L went from 38% to 58%.26 Blood calcium did not change in any of them.

1,000 IU is also the highest daily dose a health supplement in Singapore may carry.

Why D3 and not D2

In a 12-week trial of 335 healthy women, D3 raised blood vitamin D by about 15 nmol/L more than the same dose of D2.27

Vitamin K2

For bone

100 mcg

MK-7

What it does

Supports bone health, with vitamin D3 and zinc. K2 activates osteocalcin, the protein that holds calcium in bone.

Why 100 mcg

In a Japanese dose-finding study, 100 mcg a day was the lowest dose that made a measurable difference to osteocalcin activation.8

Japan · 4 weeks57 women Day Pack · 100 mcg 50 mcg100 mcg200 mcg no difference differed from no MK-7

Study figures describe the individual ingredients, not Day Pack itself.

100 mcg ≈ 10 g of natto13Japanese fermented soybeans

Why MK-7 and not K1

In 15 healthy volunteers given 100 mcg of each, K1 was mostly gone from the blood within 4 hours, while MK-7 took about 3 days to halve. A daily dose of MK-7 therefore builds to a steady level; a daily dose of K1 does not.28

K1mostly gone within 4 hours MK-7about 3 days to halve 0 h24 h48 h72 h
Two more MK-7 studies

At 60 mcg a day for a week, MK-7 appeared in the blood of all ten women tested and MK-4 in none.29 Even 56 mcg a day, in a yogurt drink taken for 12 weeks by 60 healthy adults, lowered under-carboxylated osteocalcin by a third against the basic drink.30

Before you take it

Consult a healthcare professional prior to use if you are taking a blood thinner such as warfarin.

Zinc

For the mind, energy and bone

15 mg

Bisglycinate

What it does

Helps in energy metabolism and supports mental function. Supports bone health and helps maintain healthy hair, skin and nails.

Your body has no dedicated zinc store, so it needs a daily supply.14 In a chelated form the body absorbs.

Why 15 mg

Enough to raise blood zinc, and well short of where copper status is affected.

0 mg10 mg20 mg30 mg 9.5 mg15 mg dose11 mg20 mg dose11.2 mg30 mg dose Day Pack

Dashed outline: the dose. Filled: the amount absorbed. 8 healthy adults, zinc sulfate in water, empty stomach.31

The two studies

In healthy adults aged 55 to 87, 15 mg a day for 6 months raised blood zinc with no adverse effect on copper or iron status.32

Absorption is not all-or-nothing: in a small study of 8 healthy adults given zinc sulfate in water on an empty stomach, the amount absorbed kept rising past 15 mg but by less and less, from 9.5 mg at 15 mg to 11 mg at 20 mg and 11.2 mg at 30 mg.31

15 mg is also the most a health supplement in Singapore may carry.

Why bisglycinate

At the same 15 mg, zinc bisglycinate reached the blood better than zinc gluconate in a 12-woman crossover study.33

Probiotics

For the gut

10 billion

CFU · ten strains

What they do

Help promote healthy gut flora.

Why 10 billion

Health Canada allows a plain "contributes to healthy gut flora" claim for well-studied species from 1 billion CFU per serving, held through shelf life.34 Day Pack carries 10 billion at manufacture; the count at the end of shelf life is being confirmed with our manufacturer, and this line will carry it once it is in.

Does more CFU matter?

In the strains that have been measured, more CFU means more of the ingested bacteria recovered at the far end of the gut: in 71 healthy adults given a Bifidobacterium strain at 100 million to 100 billion CFU a day for 3 weeks, recovery in stool rose with the dose.35

Why every day

Probiotics pass through; they do not move in. In 22 healthy adults taking a Lactobacillus plantarum strain, lactobacilli in stool rose within a week of starting and fell back within a week of stopping.36

TAKING IT DAILY Start+1 weekStop+1 week Illustration of the pattern, not measured data

Limits

Those studies tested single, named strains. Ours are ten species whose strain identities we are confirming, so we describe the pattern, not a result for Day Pack.

Study figures describe the individual ingredients at the doses in Day Pack, not Day Pack itself. Where a study used a different dose, the sentence says so.

06

What we left out

No caffeine. No stimulants.

No calcium.

Vitamin D3 helps your body absorb and use the calcium from your food.

No proprietary blend.

Every dose is on the front of the pack.

07 · What we won't claim

No human trial has evaluated Day Pack's full formula. Every claim here belongs to one ingredient, and each one has its own footnote.

No trial has tested Day Pack's exact dose of B3, B5 or biotin. Those doses cover a day's requirement (B3, biotin) or sit with the B-complex trials (B5). We say so rather than borrow a study that does not fit. The reasons for the B1, B2 and B6 amounts are being documented with our manufacturer and will be added here.

We do not claim the probiotic changes your microbiome. In healthy adults, probiotics have not been shown to change the diversity of gut bacteria,37 and the strains are found only while you keep taking them.36

08 · How to take it

One sachet each morning, after food.

Contains: soybeans, milk and products thereof.

If you take a blood thinner such as warfarin, consult a healthcare professional first.

Keep out of reach of children.

References

Each entry lists the study type, design and, where an ingredient maker funded or supplied the study, who.

  1. ReferenceNINDS (2025). Brain Basics: Understanding Sleep. www.ninds.nih.gov/health-information/public-education/brain-basics/brain-basics-understanding-sleep
  2. RCTGardiner C et al. (2025). Sleep 48(4):zsae230. doi.org/10.1093/sleep/zsae230Placebo-controlled, single doses. 23 healthy men. Sleep measured at home.
  3. ReferenceUS FDA (2024). Spilling the Beans: How Much Caffeine is Too Much? www.fda.gov/consumers/consumer-updates/spilling-beans-how-much-caffeine-too-muchCaffeine content of a cup of coffee.
  4. MechanismPabst O (2012). Nat Rev Immunol 12(12):821–832. doi.org/10.1038/nri3322Review. Antibody-producing cells in the gut lining.
  5. RCTKennedy DO et al. (2010). Psychopharmacology 211(1):55–68. doi.org/10.1007/s00213-010-1870-3Randomised, double-blind, placebo-controlled. 215 working men, 33 days. A B-complex formula with 500 mg vitamin C, not Day Pack. Funded by Bayer, maker of the formula tested.
  6. Sender R, Milo R (2021). Nat Med 27:45–48. doi.org/10.1038/s41591-020-01182-9Cells replaced each day.
  7. Sender R, Fuchs S, Milo R (2016). PLoS Biol 14(8):e1002533. doi.org/10.1371/journal.pbio.1002533Cells in the human body.
  8. RCTInaba N et al. (2015). J Nutr Sci Vitaminol 61(6):471–480. doi.org/10.3177/jnsv.61.471Dose-finding study in 57 women, then a 12-week randomised, double-blind, placebo-controlled trial in 120 healthy adults. All three authors work for J-Oil Mills, an MK-7 maker.
  9. ReferenceNIDDK (2017). Your Digestive System & How It Works. www.niddk.nih.gov/health-information/digestive-diseases/digestive-system-how-it-works
  10. MechanismKennedy DO (2016). Nutrients 8(2):68. doi.org/10.3390/nu8020068Review. B vitamins in energy production.
  11. ReferenceNIH Office of Dietary Supplements. Vitamin C: Fact Sheet for Health Professionals. ods.od.nih.gov/factsheets/VitaminC-HealthProfessional
  12. ObservationalDivakar U et al. (2020). Int J Environ Res Public Health 17(1):164. doi.org/10.3390/ijerph17010164213 indoor workers at four Singapore workplaces.
  13. ReferenceNIH Office of Dietary Supplements. Vitamin K: Fact Sheet for Health Professionals. ods.od.nih.gov/factsheets/VitaminK-HealthProfessionalMK-7 content of natto.
  14. MechanismMaywald M et al. (2017). Int J Mol Sci 18(10):2222. doi.org/10.3390/ijms18102222Review.
  15. RCTBenton D, Griffiths R, Haller J (1997). Psychopharmacology 129(1):66–71. doi.org/10.1007/s002130050163Placebo-controlled. 120 young women, 2 months, 50 mg thiamine.
  16. Absorption studyZempleni J, Galloway JR, McCormick DB (1996). Am J Clin Nutr 63(1):54–66. doi.org/10.1093/ajcn/63.1.54Riboflavin uptake from single doses.
  17. RCTDeijen JB et al. (1992). Psychopharmacology 109(4):489–496. doi.org/10.1007/BF02247729Placebo-controlled. 76 healthy men aged 70 to 79, 3 months, 20 mg B6.
  18. RCTBryan J, Calvaresi E, Hughes D (2002). J Nutr 132(6):1345–1356. doi.org/10.1093/jn/132.6.1345211 healthy women, 35 days.
  19. ReferenceNIH Office of Dietary Supplements. Vitamin B12: Fact Sheet for Health Professionals. ods.od.nih.gov/factsheets/VitaminB12-HealthProfessional
  20. RCTWhite DJ et al. (2015). Nutrients 7(11):9005–9017. doi.org/10.3390/nu7115451Placebo-controlled. 58 young adults, 4 weeks.
  21. Absorption studyLevine M et al. (2001). Proc Natl Acad Sci USA 98(17):9842–9846. doi.org/10.1073/pnas.171318198Healthy young women.
  22. Absorption studyLevine M et al. (1996). Proc Natl Acad Sci USA 93(8):3704–3709. doi.org/10.1073/pnas.93.8.3704
  23. RCTHuang HY et al. (2002). Am J Clin Nutr 76(3):549–555. doi.org/10.1093/ajcn/76.3.549Placebo-controlled. 184 healthy non-smokers, 2 months, 500 mg a day.
  24. Absorption studyHeaney RP et al. (2003). Am J Clin Nutr 77(1):204–210. doi.org/10.1093/ajcn/77.1.20467 men, 20 winter weeks. Blood vitamin D by dose.
  25. Absorption studyVieth R, Chan PC, MacFarlane GD (2001). Am J Clin Nutr 73(2):288–294. doi.org/10.1093/ajcn/73.2.288Toronto adults, 3 months.
  26. Dědečková E et al. (2023). Life 13(3):808. doi.org/10.3390/life1303080872 young adults, 60 days.
  27. RCTTripkovic L et al. (2017). Am J Clin Nutr 106(2):481–490. doi.org/10.3945/ajcn.116.138693335 healthy women, 12 weeks, D3 against D2.
  28. Absorption studySchurgers LJ et al. (2007). Blood 109(8):3279–3283. doi.org/10.1182/blood-2006-08-04070915 healthy volunteers, K1 against MK-7.
  29. Absorption studySato T, Schurgers LJ, Uenishi K (2012). Nutr J 11:93. doi.org/10.1186/1475-2891-11-9310 women, 60 mcg a day for a week.
  30. RCTKnapen MHJ et al. (2015). J Nutr Sci 4:e35. doi.org/10.1017/jns.2015.2560 healthy adults, 12 weeks, MK-7 in a fortified yogurt drink. Funded by FrieslandCampina; MK-7 from NattoPharma.
  31. Absorption studyTran CD et al. (2004). Am J Clin Nutr 80(6):1570–1573. doi.org/10.1093/ajcn/80.6.15708 healthy adults, zinc sulfate in water.
  32. RCTHininger-Favier I et al. (2007). Br J Nutr 97(3):569–578. doi.org/10.1017/S0007114507432974Healthy adults aged 55 to 87, 6 months.
  33. Absorption studyGandia P et al. (2007). Int J Vitam Nutr Res 77(4):243–248. doi.org/10.1024/0300-9831.77.4.243Crossover. 12 women, single 15 mg dose. A co-author worked at Oenobiol; the bisglycinate came from Albion.
  34. ReferenceHealth Canada (2024). Health claims about microorganisms and use of the term probiotic. www.canada.ca/en/health-canada/services/food-nutrition/food-labelling/health-claims/microorganisms-term-probiotic.html
  35. Larsen CN et al. (2006). Eur J Clin Nutr 60(11):1284–1293. doi.org/10.1038/sj.ejcn.160245071 healthy adults, 3 weeks, doses from 100 million to 100 billion CFU.
  36. Goossens D et al. (2003). Aliment Pharmacol Ther 18(5):495–505. pubmed.ncbi.nlm.nih.gov/1295042222 healthy adults, one Lactobacillus plantarum strain.
  37. Éliás AJ et al. (2026). BMC Med 24:71. doi.org/10.1186/s12916-025-04602-0Probiotics and gut bacterial diversity in healthy adults.
  38. ObservationalVisvalingam N et al. (2020). Sleep Health 6(3):277–287.Cited on the Day Pack page: 2 in 3 full-time employees in Singapore sleep less than seven hours a night.