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Vitamin D3 5000IU Vitamin D3 5000IU 100 caps.
Seeking Health
13.48 $
Location: eu

Vitamin D3 5000IU 100 caps.

From 3 units only: 13.21 $ / Units. -2%

Shipping weight: 200g

As an alternative, we recommend:

Vitamin D3 4000 IU 120 caps.
Vitamin D3 4000 IU 120 caps.
Apollo's Hegemony
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13.48 $ With VAT
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  • Contains a high dose of vitamin D3 (5000 IU per capsule)
  • Fully vegetarian active substance
  • Provides protection from many diseases
  • Ensures healthy physical and psychological development of children
  • Supports a healthy immune system
  • Facilitates intestinal calcium absorption
  • Maintains healthy bones

Seeking Health Vitamin D3 is a dietary supplement with a high dose of vegetarian-source vitamin D3 (5000 IU). Such a large dose of the active substance helps fight effectively deficiency of this vitamin in the body. Even though it is produced naturally in the skin by sunlight, this process is insufficient in our climate. The vitamin in the form of cholecalciferol in this dietary supplement supports healthy function of the whole body.

Mechanism of action of cholecalciferol
It is not without reason that vitamin D3 (cholecalciferol) is considered a prohormone. It has been shown that after absorption into the blood it is converted in the liver and kidneys where it is activated.  Its active form exerts a biological effect on the body by binding to vitamin D receptor (VDR).

Vitamin for healthy bones
Vitamin D3 is an important element responsible for normal bone structure. It helps build them properly by a double mechanism of action.

Cholecalciferol regulates levels of many enzymes in the body. They include aromatase which converts testosterone in oestrogen. Proper levels of vitamin D3 and aromatase help maintain normal bone density.

In addition, the active form of the vitamin binds to the vitamin D receptor and has thus an impact on bone cell proliferation and bone mineralisation. It supports proper uptake of calcium and phosphorous ions from the bloodstream into bones and facilitates their incorporation. It is also responsible for healthy teeth.

Impact on the endocrine system
Vitamin D is very similar structurally to steroid hormones. Both they and vitamin D are based on cholesterol. Normal blood cholecalciferol levels are responsible for normal function of the endocrine system in the body.

It has been observed that individuals with its deficiency have frequently insufficient testosterone levels. Replenishing levels of this vitamin helps restore normal levels of androgenic hormones. This is manifested by improved libido, high-quality semen production and general well-being in men.

A positive effect of vitamin D has been demonstrated on parathyroid hormones and oestrogen.

For a healthy nervous system
The nervous system contains an enzyme activating vitamin D3. Owing to that, the vitamin exerts a positive impact on its function. The greatest amounts of cholecalciferol were observed in the hypothalamus and dopaminergic neurons of the grey matter. The main function of the vitamin is to protect nerve cells from harmful factors.

One of them is excitotoxicity, namely excessive destructive neuronal excitability which is caused by too high concentration of calcium ions in the blood. Consequently, vitamin D3 shows neuroprotective properties.

Studies confirm that cholecalciferol deficiency is associated with increased degeneration of neurolemma. This sheath is a structure which surrounds the nerve cell and thus ensures normal neurotransmission. Its degeneration can be observed in individuals with multiple sclerosis. What is more, stressors, which also damage the nervous system, contributes to the development of Alzheimer’s and Parkinson’s disease. Because of that, adequate levels of this vitamin in the body help reduce the incidence of these diseases.

Vitamin D3 allows you also to get normal depth of sleep. This results in efficient regeneration of the nerve tissue which helps maximise the effectiveness of its function. As a consequence, we can have a better mood and improved cognitive functions.

It has been demonstrated that individuals with depression have low blood vitamin D3 levels.

Protection from diseases
Healthy vitamin D3 levels support the body in fighting against diseases. It is due to the fact that the function of immune cells is improved. Because of that, the body combats pathogens more efficiently.

It has been shown that cholecalciferol improves the function of monocytes and thus reduces their excessive adhesion to blood vessel walls. This reduces the incidence of cardiovascular diseases.

By stimulating the immune system into more efficient function and affecting many bodily processes, vitamin D3 reduces the likelihood of some cancer types.

For a healthy heart
Vitamin D3 deficiency is associated with cardiovascular diseases. It helps protect the heart and blood vessels from too high blood pressure. The vitamin decreases therefore the secretion of renin which belongs to the renin–angiotensin–aldosterone system responsible for regulating blood pressure. A decrease in renin secretion causes a series of events which leads to a drop in blood pressure.

By transferring calcium from the bloodstream into proper tissues, cholecalciferol prevents its excessive deposition in blood vessel walls. As a result, it reduces calcification of blood vessels and contributes to their normal structure. It helps also reduce the growth of atherosclerotic plaque, the main factor in the development of ischaemic heart disease.

Improves carbohydrate balance
Vitamin D3 sensitises the body to insulin. As a consequence, it helps utilise properly carbohydrates found in the blood. This reduces the incidence of hyperglycaemia, which is dangerous especially for diabetics.  In addition, cholecalciferol contributes to normal utilisation of glucose, thereby inhibiting the development of diabetes and providing effective support for obese individuals with insulin resistance.

Increased energy levels
Even though VDRs are not found skeletal muscle cells, vitamin D3 affects directly the effectiveness of muscle function. This is due to improved calcium balance and its overall impact on bodily function. It has been proven that properties of this vitamin promotes recovery after injuries.

Effect on pregnant women
It has been observed that blood vitamin D levels in pregnant and breastfeeding women are significantly decreased. This is due to increased requirements for this vitamin because it has a vital function in child development. Cholecalciferol is important especially during the first trimester of pregnancy.

Seeking Health Vitamin D3 is a dietary supplement recommended mainly to individuals affected with this vitamin deficiency.  Even though the human body has the ability to synthesise cholecalciferol, the moderate climate does not help maintain its normal production. Because of that, this vitamin deficiency may affect almost everyone. A high-risk group comprises pregnant women, the elderly and physically active individuals. Normal levels of vitamin D3 metabolites are responsible for healthy function of the whole body, especially the cardiovascular, motor and immune system.

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Container size: 100 capsulesServing size: 1 capsuleServings per container: 100
per 1 capsuleamount%DV
Vitamin D3 (as Cholecalciferol)5000 I.U.625%

Other ingrednients

Microcrystalline cellulose, HPMC (capsule), ascorbyl palmitate, and silica.

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Best to combine with

Vitamin D


Vitamin D belongs to fat soluble vitamins, occurs in three forms: calciferol (vitamin D1) ergocalciferol (vitamin D2) and cholecalciferol (vitamin D3), it is formed under the action of sunlight for at least 15 minutes per day. In the absence of sunlight it should be administered in the diet in the form of fish oil (Vitamin A + D3) and fish oils. It is responsible for the absorption of calcium and phosphorus. It is the building substance of bone tissue particularly necessary during pregnancy, childhood, and for athletes. It is a component of dietary supplements and nutrients among competetive athletes. Deficiency of vitamin D causes children growth inhibition, and rickets.
For adults - deficiency causes osteomalacia.
of vitamin D causes headaches, alopecia, nausea, drowsiness, blurred vision, pain in the long bones, the deposition of calcium deposits.
Dosage: 400 IU units during the day.




Cholecalciferol, or vitamin D3, is an organic chemical that belongs to the family of D vitamins. It is naturally found in fatty fish, fish oil, egg yolks, milk and dairy products. It is also synthesized in the human body. It is formed from 7-dehydrocholesterol present in the keratinocytes of the spinous and the basal layers of the epidermis, and a pre-requisite for initiating this process is the action of 290-315 nm wavelength UVB radiation on the skin.

Cholecalciferol is a biologically inactive compound. In the body, it undergoes enzymatic hydroxylation – first in the liver, with the participation of 25-hydroxylase, when calcidiol is formed and secondly in the kidneys, where under the influence of 1-α-hydroxylase, calcidiol is converted into the final active form – calcitriol.

The most important role of vitamin D3 in the body is the regulation of calcium-phosphate metabolism, which directly affects normal skeletal mineralization. In addition, it is involved in cell proliferation and differentiation, insulin secretion, as well as in some functions of the nervous, endocrine and immune systems.

Cholecalciferol is the most popular form of vitamin D used in dietary supplements. Studies show that supplementation with vitamin D in this form most effectively and rapidly raises the level of 25 (OH) D3 – a metabolite that is a marker of the level of vitamin D in the body.

Dosage: according to RDI standards for individual age groups.

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