Pack size: 120 capsules

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D3 4000

Cholecalciferol from lanolin, 4,000 IU

56,99 zł

Supports normal immune system function
Helps maintain healthy bones and teeth
Supports normal muscle function

Overview

A concentrated, convenient vitamin D3 formula for healthy adults over 75. Each D3 4000 capsule provides 100 µg, or 4000 IU, of cholecalciferol to support immune function, healthy bones, and normal muscle function.

At the heart of the formula / D3 4000

Thoughtful support. Clear purpose.

01Supports normal immune system function
02Helps maintain healthy bones and teeth
03Supports normal muscle function
04Helps with normal calcium and phosphorus absorption
05Supports normal blood calcium levels

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D3 4000

Made for your daily routine.

We chose lanolin-derived cholecalciferol in coconut MCT oil. Vitamin D is fat-soluble, making an oil base a suitable carrier.

One capsule with breakfast fits into a consistent daily routine. Each bottle provides 120 days of use. This focused D3 formula provides a high serving and is intended only for the age group specified on the label.

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D3 4000

Why does vitamin D3 matter?

Vitamin D3 helps maintain healthy bones and teeth and supports normal muscle and immune function. It contributes to calcium and phosphorus absorption and use, and to cell division. Skin synthesis depends on factors including season and sun exposure. D3 4000 is a concentrated formula intended only for healthy adults over 75, as specified for this product.

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D3 4000

What does research say about D3 4000?

Vitamin D3 studies show that regular supplementation increases 25(OH)D, a marker of vitamin D status. Trials using 4,000 IU daily found a greater response than lower amounts, with tolerability assessed in specific adult populations. This does not establish suitability for everyone. D3 4000 provides cholecalciferol in MCT oil and is intended only for healthy adults over 75. Account for vitamin D from all sources.

Ingredients / Doctor Life

Every ingredient. Clearly explained.

Each ingredient, its form and quantity — in one place.

Ingredient amounts for the servings shown in the table.
Ingredient	1 capsule
Vitamin D3	100 mcg (4,000 IU), 2,000%*

*NRV: Nutrient Reference Value

Full ingredient list

Coconut MCT oil (medium-chain fatty acids); gelatin; humectant: glycerol; water; vitamin D3 (cholecalciferol).

How to use

Part of your daily rhythm.

How to use

Take 1 capsule with food at breakfast.

Important information

Do not exceed the recommended daily serving. Food supplements should not replace a varied diet. A balanced diet and a healthy lifestyle are recommended. Store at room temperature, at or below 25°C, out of reach of young children. This food supplement is intended only for healthy adults over 75 years of age.

Science & sources

Understand the formula.

These publications examine vitamin D's importance for immune, bone, and muscle health, alongside studies of 4,000 IU daily in adults.

These publications concern the studied ingredients or formulas. They do not all evaluate the finished Doctor Life product, and research results do not guarantee individual outcomes.

01Efficacy and safety of vitamin D3 intake exceeding the lowest observed adverse effect level

R. Vieth, P.C. Chan, G.D. MacFarlane

The American Journal of Clinical Nutrition (2001), 73(2), 288–294. DOI: 10.1093/ajcn/73.2.288; PMID: 11157326.

This study evaluated long-term daily intake of 1,000 and 4,000 IU of vitamin D3. The 4,000 IU amount increased 25(OH)D levels more effectively, while monitored safety measures remained within normal ranges. It provides a direct research reference for the amount in D3 4000.

Read publication ↗

02Randomized comparison of the effects of the vitamin D3 adequate intake versus 100 mcg (4000 IU) per day on biochemical responses and the wellbeing of patients

R. Vieth, S. Kimball, A. Hu, P.G. Walfish

Nutrition Journal (2004), 3, 8. DOI: 10.1186/1475-2891-3-8; PMID: 15260882.

A randomized study compared a lower vitamin D3 intake with 4,000 IU daily in people with insufficient vitamin D levels. The higher amount produced a greater increase in 25(OH)D and a reduction in parathyroid hormone, without affecting calcium levels, demonstrating the effect of consistent use at this amount.

Read publication ↗

03Safety and tolerability of high-dose daily vitamin D3 supplementation in the vitamin D and type 2 diabetes (D2d) study

K.C. Johnson, M. Pittas, S. Margolis et al.

European Journal of Clinical Nutrition (2022), 76, 1117–1124. DOI: 10.1038/s41430-022-01096-6; PMID: 35140313.

The D2d safety analysis examined daily use of 4,000 IU of vitamin D3 in people with overweight or obesity and an increased risk of diabetes. Supplementation was well tolerated. The publication provides longer-term data on this specific amount.

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04Guidelines for Preventing and Treating Vitamin D Deficiency: A 2023 Update in Poland

P. Płudowski, B. Kos-Kudła, M. Walczak et al.

Nutrients (2023), 15(3), 695. DOI: 10.3390/nu15030695; PMID: 36771403.

Polish guidelines set out vitamin D supplementation according to age, body weight, sun exposure, and individual needs. They explain why higher amounts should be selected carefully, taking total vitamin D intake from all sources into account.

Read publication ↗

FAQ / D3 4000

Good questions. Clear answers.

Talk to us ↗

What does 4,000 IU mean?

4,000 IU equals 100 µg of vitamin D3. These are two units for the same amount. This is also the adult tolerable upper daily intake level from all sources, so do not increase it yourself.

Why take it with food?

Vitamin D3 is fat-soluble. The formula uses coconut MCT oil, and the directions specify taking it with breakfast. A consistent meal also makes regular use easier.

What does lanolin-derived vitamin D3 mean?

Lanolin comes from sheep’s wool and is used to produce cholecalciferol, or vitamin D3. This is the same vitamin D form the body produces in response to sunlight.

Is it suitable for vegans or vegetarians?

No. The D3 is derived from lanolin and the capsule contains gelatin, so the product is not classified as vegan or vegetarian.

Who is D3 4000 intended for?

The product is intended only for healthy adults over 75. It provides a concentrated vitamin D3 serving for the group specified on the label. Account for any other products containing vitamin D.

How long does one bottle last?

Each bottle contains 120 capsules. At 1 capsule daily, it provides 120 days of use—approximately four months.

Can I combine D3 4000 with other vitamin D supplements?

Do not combine vitamin D sources without checking the total amount. One capsule provides 100 µg, so any additional vitamin D must be included in your total daily intake. Consult your doctor or pharmacist if unsure.

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