Why was the labeling of Maximum D3® changed to 325 mcg (13,000 IU)?

The Maximum D3 labeling has changed from 10,000 IU to 325 mcg (13,000 IU), but the product and formulation have not changed. The change was made because of new FDA labeling requirements. Under the new guidelines, Maximum D3 could continue to be labeled 10,000 IU (250 mcg) or 13,000 IU (325 mcg), but the 13,000 IU labeling was chosen to most accurately reflect the contents of Maximum D3.

The FDA determined that the contents of several substances, including vitamin D, should be stated in micrograms (mcg or µg) and no longer need to be in International Units (IU). The US food labeling laws apply to nutritional supplements and require that actual content for fat soluble vitamins be between 100% and 130% of the content stated on the label. Because of some possible ambiguity in the most current regulations (Federal Register / Vol. 81, No. 103 / Friday, May 27, 2016 / Rules and Regulations), we have elected to use the actual content of Maximum D3 rather than an acceptable arbitrary value. The product and formulation have not changed.

Why is Maximum D3® a superior vitamin D supplement?

Maximum D3® is effective, convenient, high-quality, made in the USA and available OTC.

Maximum D3® was designed by a doctor when he was frustrated by the lack of high-quality supplements available to his patients.  Maximum D3® was carefully formulated to be effective, convenient and safe.

Some other vitamin D supplements contain vitamin D2 (a less effective source of vitamin D), do not contain enough vitamin D to be effective and/or are not designed to be easily digested by the human body.  Additionally, testing through an independent lab has shown that some other retail vitamin D supplements have LESS dosage than stated, contain anaerobic bacteria and/or contain mold.

Maximum D3® is one of the few vitamin D preparations that has undergone INDA review by the FDA. All Maximum D3® product is tested to ensure it meets the dosing stated on the package.

Quality counts and quality is our priority!

Benefit Maximum D3® Competitors
  • Made with a digestible oil to help the body absorb vitamin D
  • Each capsule consistently meets the stated dose
  • Once a week dose or as directed by a provider
  • Every batch is tested for quality, contamination & consistent dosing
  • Designed for superior product stability
Made in the USA
  • Capsules are manufactured, packaged & warehoused in FDA-registered facilities & inspected facilities
No Prescription Needed
  • Available without a prescription at a pharmacy or online
What is the expiration date for Maximum D3®?

Please refer to the order page for the current expiration date.  

Do I have to use a credit card to order Maximum D3®?

No, you can pay by check.  For check orders, please contact us at: 217-320-1597

Is Maximum D3® sold near me?

Maximum D3® is sold by many pharmacies, physicians and retailers.  Please contact your local business or physician to see if they carry Maximum D3®.  For online orders, please click here.

Is Maximum D3® gluten-free?

Yes, Maximum D3® is gluten-free.  There is NO gluten in the product.

Is Maximum D3® Kosher?

Maximum D3® is not Kosher.  Maximum D3® is not packaged in a Kosher facility. The gel caps before filling with soy lecithin and cholecalciferol are Kosher (Ko).  BSE free bovine (only) gel caps are manufactured in France or Japan by Capsugel to obtain a product which does not contain pork.

Does Maximum D3® contain GMOs?

No, Maximum D3® does not contain genetically-engineered ingredients (which are commonly referred to as GMOs or genetically modified ingredients).  Maximum D3® is non-GMO.

What is the correct dose of vitamin D?

The correct dose of vitamin D is generally thought to be about 1,200 to 1,400 IU/day and can be taken daily, weekly or perhaps monthly.  There is some data to suggest that very large doses (600,000 IU injections every 6 months) might not be good.  More is not always better, and too much can be harmful.

Maximum D3® 10,000 IU was designed to meet the demonstrated needs in normal persons with the convenience of being taken just once per week.

The proper dose of vitamin D can vary based on your health condition, so it is always best to consult your physician about your specific health needs.

More detailed answer –

The dose of 1200-1400IU/day assumes a properly formulated and consistent product. There are problems:

Testing has consistently shown that a considerable portion of vitamin D sold in the United States is of poor quality. Potency, absorption and contamination are all issues. 

More confusing is that most of vitamin D’s role in the human body is not well understood.  The effect on calcium and bone are reasonably well understood. However, much more vitamin D is used at the local cellar level to regulate processes of our immune system. This is why vitamin D keeps coming up in relation to cancer and infections.

There is an ongoing disagreement in the academic literature about how to address this. The formal recommendations used for labeling are based on recommendations from a report by the Institute of Medicine in 2010 (1). This report only used data for overt bone disease. That decision cited a lack of adequate data to address other factors. (Best explained in the introduction by Dr. A. Catharine Ross, Chair.) The Endocrine Society and others have raised other questions and suggestions (2) and the issue remains an ongoing topic in the medical literature.

1 - http://nationalacademies.org/hmd/Reports/2010/Dietary-Reference-Intakes-for-Calcium-and-Vitamin-D.aspx

2 - http://press.endocrine.org/doi/10.1210/jc.2011-0385

What should my Vitamin D blood level be?

Ideal blood levels vary by individual, but the target range is generally between 30 and 60ng/ml of 25(OH) cholecalciferol.  It is generally recognized that the minimal blood level needed to prevent overt bone disease is 20 ng/ml.

This answer is based on blood levels seen in persons with substantial sun exposure and limited clothing (lifeguards, agricultural workers, primitive groups).

Maximum D3® was designed to meet the demonstrated needs in normal persons and still provide a substantial safety margin if other sources of vitamin D are consumed.

What are the contents of Maximum D3®?

The only ingredients in Maximum D3® are vitamin D3 (cholecalciferol), non-GMO soybean lecithin, FD&C Blue 1 on half of the gelatin shell and bovine gelatin.

The pill is a small hard gel cap containing 325 mcg of quality cholecalciferol in a digestible oil base.  The capsules are manufactured, packaged and warehoused in FDA-registered and inspected facilities.  Quality, packaging and stability are to available USP and FDA standards.


Contains: Soy


Allergen List  
Cereals containing Gluten and products thereof NO
Crustaceans (mussels and shellfish) and products thereof NO
Eggs and products thereof NO
Fish and products thereof NO
Peanuts and products thereof NO
Soybeans and products thereof YES
(Lecithin derived from soy)
Milk and dairy products (including lactose) NO
Nuts and products thereof NO

Additional information

Composition and Origin (weights are approximate)  
Lecithin derived from soy, Non-GMO (USA) 287mg (0.01 ounce)
Kosher bovine gelatin caps (Japan or France) 73 mg (0.0026 ounce)
Cholecalciferol - vitamin D3 (USA) 325 mcg (0.00001 ounce)
       FD&C Blue 1 (FDA-approved)  
       There is no coloring in the oil.  

The dosage and formulation have been intelligently designed:

  • The hard gel cap for stability
  • The digestible oil for consistency of potency (mixing), stability and absorption

Maximum D3® conforms to USP standards <581> for purity, <2091> for weight variation, and <2040> for disintegration and dissolution and conforms to available USP standards for ingredients.

PLEASE NOTE: Each production lot is tested prior to distribution. Ingredients are also tested prior to production and later testing is done for evidence of contamination or degradation.

Is there much difference between vitamins D2 and D3 and is it important?

D2 and D3 are different, and it is important to note the differences.


D2 is a plant hormone; animals make and use D3.  Both D2 and D3 are absorbed similarly, and both will activate the vitamin D receptor.  The difference is in the molecular arrangement of the side chains.  The D2 side chain provides a convenient attachment for an enzyme (not intended for vitamin D metabolism) that causes the D2 version to be broken down much more quickly and differently than D3.  Therefore, D2 is not as good for loading or maintaining vitamin D levels.

How these differences affect regulation of vitamin D activity at the cellular level is not well understood.  Note that Europe largely moved away from D2 about two decades ago.

Maximum D3 - D2 & D3 Difference

Why is vitamin D a hormone and not a vitamin?

Technically, D3 is a pro-hormone and not a vitamin, but it can be taken as if it were a vitamin. Humans can make vitamin D3 but require sunlight on exposed skin to do so.  Housing, clothing and indoor jobs were not in the original design specifications.  D3 is an intermediary prohormone made by the sunlight step.  Importantly, hormone production and activity require regulation to work correctly.  Hence, we need enough, but not too much, D3 to replace the lack of sun exposure.

How much Calcium do I need?

The Institute of Medicine generally recommends that adults consume 1,000 mg of calcium per day with a maximum limit of 2,000 mg.  However, recommended calcium intake can vary by age, gender and health condition.

General Calcium Principles

  • The Institute of Medicine and the National Osteoporosis Foundation both recommend dietary sources as the preferred method of calcium intake.  Calcium guidelines are for total dietary calcium, not supplement requirements.
  • The Institute of Medicine has recently raised concern about the ingestion of too much calcium carbonate in pill form (particularly among older women).
  • Calcium considerations are influenced greatly by several medical conditions - especially kidney disease - individual professional advice should be considered.
  • Current calcium supplements do not contain remotely adequate amounts of vitamin D for use as standalone vitamin D supplementation.
  • Calcium should not be taken with some medications.
  • Calcium carbonate requires acid for absorption and should be taken with food.
  • Calcium carbonate supplement contains 40% elemental calcium.
  • Calcium citrate does not require acid for absorption and contains 21% calcium.
  • Our bones are made of calcium phosphate and dairy products are an excellent source.
  • Convenience, cost and palatability are major considerations. (avoid bone meal products because of possible heavy metal contamination, "coral calcium" is calcium carbonate)

Vitamin D status appears to affect calcium absorption more than the amount of calcium taken:

Large doses of calcium supplementation may interfere with phosphorus adsorption:

Selected Food Sources of Calcium

Food Calcium (mg) % DV*
Yogurt, plain, low fat, 8 oz. 415 42%
Yogurt, fruit, low fat, 8 oz. 245-384 25%-38%
Sardines, canned in oil, with bones, 3 oz. 324 32%
Cheddar cheese, 1 ½ oz shredded 306 31%
Milk, non-fat, 8 fl oz. 302 30%
Milk, reduced fat (2% milk fat), no solids, 8 fl oz. 297 30%
Milk, whole (3.25% milk fat), 8 fl oz 291 29%
Milk, buttermilk, 8 fl oz. 285 29%
Milk, lactose reduced, 8 fl oz.** 285-302 29-30%
Mozzarella, part skim 1 ½ oz. 275 28%
Tofu, firm, made w/calcium sulfate, ½ cup*** 204 20%
Orange juice, calcium fortified, 6 fl oz. 200-260 20-26%
Salmon, pink, canned, solids with bone, 3 oz. 181 18%
Pudding, chocolate, instant, made w/ 2% milk, ½ cup 153 15%
Cottage cheese, 1% milk fat, 1 cup unpacked 138 14%
Tofu, soft, made w/calcium sulfate, ½ cup*** 138 14%
Spinach, cooked, ½ cup 120 12%
Instant breakfast drink, various flavors and brands, powder prepared with water, 8 fl oz. 105-250 10-25%
Frozen yogurt, vanilla, soft serve, ½ cup 103 10%
Ready to eat cereal, calcium fortified, 1 cup 100-1000 10%-100%
Turnip greens, boiled, ½ cup 99 10%
Kale, cooked, 1 cup 94 9%
Kale, raw, 1 cup 90 9%
Ice cream, vanilla, ½ cup 85 8.50%
Soy beverage, calcium fortified, 8 fl oz. 80-500 8-50%
Chinese cabbage, raw, 1 cup 74 7%
Tortilla, corn, ready to bake/fry, 1 medium 42 4%
Tortilla, flour, ready to bake/fry, one 6" diameter 37 4%
Sour cream, reduced fat, cultured, 2 Tbsp 32 3%
Bread, white, 1 oz 31 3%
Broccoli, raw, ½ cup 21 2%
Bread, whole wheat, 1 slice 20 2%
Cheese, cream, regular, 1 Tbsp 12 1%

*DV=Daily Value
** Calcium values are only for tofu processed with a calcium salt. Tofu processed with a non-calcium salt will not contain significant amounts of calcium.

For foods not listed in this table, please refer to the U.S. Department of Agriculture's Nutrient Database Website: https://ndb.nal.usda.gov/ndb/

There are a number of other good sites that address calcium, including:

Office of Disease Prevention & Health Promotion – Food Sources of Calcium

MAYO Clinic - Calcium and calcium supplements: Achieving the right balance

National Institutes of Health – Calcium Fact Sheet for Health Professionals

USDA’s Nutrition.gov – Website

Should I take supplemental vitamin K2?

UPDATE September 2019 -

To date, credible follow-up studies have failed to confirm the initially reported benefits of K2 supplementation in circumstances other than identified vitamin K deficiency. The NIH and FDA continue to group the K vitamins as a single group and the FDA has not authorized a health claim for vitamin K in the United States. https://ods.od.nih.gov/factsheets/vitaminK-HealthProfessional/

While too soon to form a conclusion, a very recent study has been released by a highly respected journal on nutrition. This registered study suggests that MK-7 supplementation may accelerate calcium deposition in atherosclerotic cardio/vascular disease. This would be an important issue for a substance that lacks clearly demonstrated benefit for the general population. There is not cause for panic, but reassessment may be warranted.

“MK-7 supplementation tended to increase active calcification measured with 18F-NaF PET activity compared with placebo, but no effect was found on conventional CT. Additional research investigating the interpretation of 18F-NaF PET activity is necessary. This trial was registered at clinicaltrials.gov as NCT02839044.” The article and discussion are available at:



February 2018 -

As of now, the honest answer is that there is not enough consistent or quality data to definitively answer this question.  Potential problems have been identified that are unanswered.

Vitamin K refers to a group of chemical compounds that vary in their side chains. K vitamins do many things. K2 is mistakenly described as a cofactor for vitamin D. It is not. K2 does play a role in the maintenance of bone.

Deficiencies in K2 are uncommon and occur mostly in recognized situations. Human needs are not well established, but known to be tiny.  Need for supplementation in the general population has never been demonstrated. (Humans derive much of their K2 group from bacteria in their own intestinal tract.)

Bone – Extensive reviews of the studies on supplementation with K2 even in the setting of osteoporosis continue to lack consistent and convincing data.

“routine VK supplementation is not globally recommended yet in postmenopausal women affected by osteoporosis, as low-quality cross-sectional and RCTs have provided contrasting evidence. In fact, most of the studies that have analyzed the interaction between bone health and VK are characterized by several limitations and the findings should be therefore addressed with caution.”

Vitamin K and osteoporosis: Myth or reality? Review Article

Metabolism Volume 70, Pages 57 – 71 (May 2017)

Andrea Palermo, Dario Tuccinardi, Luca D'Onofrio, Mikiko Watanabe, Daria Maggi, Anna Rita Maurizi, Valentina Greto, Raffaella Buzzetti, Nicola Napoli, Paolo Pozzilli, Silvia Manfrini


Vascular disease – There is a great deal of interest in “K2 vitamins” for the prevention of vascular disease. The suggestion comes from observational epidemiology data and is far from conclusive.

“However, further studies using screening tools to find the mostly asymptomatic PAD population are warranted before our findings can be generalized.”

The relationship between vitamin K and peripheral arterial disease

Linda E.T. Vissers , Geertje W. Dalmeijer , Jolanda M.A. Boer , W.M.Monique Verschuren , Yvonne T. van der Schouw , Joline W.J. Beulens

Atherosclerosis 252 (2016) 15e20

Multiple roles - Potentially either good or more troublesome are that K2 does many things in several human tissue types. These functions are incompletely understood. Some “K” compounds have been shown to affect intracellular signaling pertinent to some types cancer cells. Suppression of K vitamins (warfarin data) are associated with a reduction in the incidence of some cancers. Whether high doses – as in some supplements promoted – are harmful is not known.

Several K2 questions remain “moving targets.”