Cholecalciferol Afortas (Vitamin D3 800 IU)
Prescription vitamin D3 supplement for prevention and treatment of vitamin D deficiency
Quick Facts About Cholecalciferol Afortas
Key Takeaways About Cholecalciferol Afortas
- Essential for bone health: Cholecalciferol Afortas provides vitamin D3 which is critical for calcium absorption and maintaining strong, healthy bones
- Take with food for best absorption: As a fat-soluble vitamin, take the tablet with a meal containing some fat to maximize absorption
- Monitor your calcium levels: Regular blood tests may be needed to check both vitamin D and calcium levels during treatment
- Watch for drug interactions: Thiazide diuretics, digoxin, and certain anticonvulsants can interact with vitamin D supplementation
- Not just for bones: Vitamin D also plays important roles in immune function, muscle strength, and overall health
What Is Cholecalciferol Afortas and What Is It Used For?
Cholecalciferol Afortas is a prescription vitamin D3 supplement containing 800 IU of cholecalciferol per tablet. It is used to prevent and treat vitamin D deficiency in adults, support calcium absorption from the intestine, and maintain healthy bone mineralization. It may also be prescribed as part of osteoporosis management.
Vitamin D is a fat-soluble vitamin that plays a crucial role in calcium and phosphorus metabolism. The body naturally produces vitamin D3 (cholecalciferol) when the skin is exposed to ultraviolet B (UVB) radiation from sunlight. However, many people do not produce enough vitamin D through sun exposure alone, particularly those living in northern latitudes, older adults, people with darker skin, and those who spend limited time outdoors. In these populations, dietary intake and supplementation become essential to maintain adequate levels.
Cholecalciferol Afortas contains 800 international units (IU) of vitamin D3, equivalent to 20 micrograms. This dose is within the range recommended by major health organizations for the prevention and treatment of vitamin D deficiency in adults. The Endocrine Society and the European Food Safety Authority (EFSA) both recognize daily intakes of 600–2000 IU as appropriate for most adults, depending on individual risk factors and baseline vitamin D status.
Once ingested, cholecalciferol undergoes two hydroxylation steps in the body. First, it is converted to 25-hydroxyvitamin D (calcifediol) in the liver, which is the main circulating form measured in blood tests. Then it is further converted to 1,25-dihydroxyvitamin D (calcitriol) in the kidneys, which is the biologically active hormone. Calcitriol binds to vitamin D receptors (VDR) found in the intestine, bones, kidneys, and many other tissues throughout the body, regulating over 200 genes involved in calcium transport, cell growth, immune function, and inflammation.
The primary indications for Cholecalciferol Afortas include treatment and prevention of vitamin D deficiency (serum 25(OH)D levels below 20 ng/mL or 50 nmol/L), adjunct therapy with calcium for the prevention and treatment of osteoporosis, and maintenance of bone health in adults at risk of deficiency. Your doctor may also prescribe it following bariatric surgery, in malabsorption syndromes, or alongside certain osteoporosis medications such as bisphosphonates that require adequate vitamin D status to work effectively.
Vitamin D deficiency is remarkably common worldwide. The World Health Organization estimates that approximately 1 billion people globally have vitamin D deficiency or insufficiency. Groups at highest risk include older adults, people with limited sun exposure, individuals with dark skin, those living at high latitudes, and patients with fat malabsorption conditions.
What Should You Know Before Taking Cholecalciferol Afortas?
Before taking Cholecalciferol Afortas, inform your doctor about any kidney problems, high calcium levels, or other medical conditions. Do not take it if you have hypercalcemia, hypervitaminosis D, or severe kidney disease. Tell your doctor about all other medicines you are taking, especially thiazide diuretics, cardiac glycosides, or anticonvulsants.
Contraindications
There are specific situations where Cholecalciferol Afortas should not be used. You must not take this medicine if you have hypercalcemia (abnormally high levels of calcium in the blood), hypervitaminosis D (excessive vitamin D in the body), or hypercalciuria (excessive calcium in the urine). Patients with severe kidney impairment (renal failure) should also avoid this medicine, as impaired kidney function affects the conversion of vitamin D to its active form and can increase the risk of calcium accumulation.
If you have a known allergy to cholecalciferol or any of the excipients in the tablet formulation, you should not take Cholecalciferol Afortas. People with kidney stones (nephrolithiasis), particularly calcium-containing stones, should discuss the risks with their doctor before starting supplementation. Conditions such as sarcoidosis and other granulomatous diseases can cause increased conversion of vitamin D to its active form, raising the risk of hypercalcemia, and require careful monitoring if vitamin D is prescribed.
Pseudohypoparathyroidism is a contraindication because vitamin D requirements may be reduced due to phases of normal vitamin D sensitivity, leading to a risk of prolonged hypercalcemia. If you are already taking other vitamin D preparations, the total dose from all sources must be considered to avoid toxicity.
Warnings and Precautions
During treatment with Cholecalciferol Afortas, regular monitoring of serum calcium levels is recommended, particularly in patients who are also taking calcium supplements, thiazide diuretics, or cardiac glycosides. Your doctor may order periodic blood tests to measure your serum 25-hydroxyvitamin D and serum calcium levels to ensure they remain within the therapeutic range.
Patients with impaired kidney function should be monitored more closely, as the kidneys play a central role in vitamin D metabolism and calcium excretion. Your doctor may measure urinary calcium excretion to assess the risk of kidney stone formation. Long-term use at high doses (well above the 800 IU in Cholecalciferol Afortas) can lead to hypercalcemia and hypercalciuria, which can cause calcification of blood vessels and organs, particularly the kidneys.
Patients with cardiovascular disease should inform their doctor, as hypercalcemia induced by vitamin D can exacerbate cardiac arrhythmias, especially in those taking digoxin. Inform your healthcare provider if you have any liver disease, as the first hydroxylation step occurs in the liver and hepatic impairment may affect vitamin D metabolism.
Do not exceed the prescribed dose. Vitamin D toxicity (hypervitaminosis D) can cause dangerously high calcium levels leading to nausea, vomiting, excessive thirst, frequent urination, kidney damage, and in severe cases, cardiac arrhythmias. If you experience any of these symptoms, stop taking the medicine and contact your doctor immediately.
Pregnancy and Breastfeeding
If you are pregnant, planning to become pregnant, or breastfeeding, consult your doctor before taking Cholecalciferol Afortas. Vitamin D supplementation during pregnancy is generally recommended at moderate doses (typically 400–800 IU daily) to support maternal and fetal bone health, and both the WHO and the American College of Obstetricians and Gynecologists (ACOG) support routine supplementation during pregnancy.
However, high doses of vitamin D during pregnancy must be avoided, as prolonged hypercalcemia can lead to physical and mental developmental delays in the newborn. Animal studies have shown teratogenic effects at very high doses. The standard 800 IU dose of Cholecalciferol Afortas is within the generally accepted safe range, but individual assessment by your doctor is essential.
Vitamin D3 and its metabolites are excreted in breast milk. While this contributes to the infant's vitamin D status, excessive maternal supplementation could lead to hypercalcemia in the breastfed infant. The 800 IU daily dose is generally considered safe during breastfeeding, but discuss dosing with your healthcare provider, especially if you are also giving vitamin D drops to your baby.
How Does Cholecalciferol Afortas Interact with Other Drugs?
Cholecalciferol Afortas can interact with several medications. Thiazide diuretics may increase the risk of hypercalcemia. Cardiac glycosides like digoxin become more toxic when calcium levels are elevated. Some medications such as orlistat, cholestyramine, and anticonvulsants reduce vitamin D absorption or increase its breakdown.
Drug interactions with vitamin D3 are clinically significant and should be carefully managed by your healthcare provider. Understanding these interactions helps ensure both the safety and effectiveness of your treatment. The most important interactions fall into two categories: drugs that increase the risk of vitamin D side effects, and drugs that reduce vitamin D effectiveness.
When vitamin D increases calcium absorption from the gut, the resulting elevated serum calcium levels can amplify the effects of certain medications or create new risks. Conversely, several medications interfere with vitamin D absorption, metabolism, or activation, potentially rendering supplementation less effective. Below is a comprehensive overview of clinically relevant drug interactions.
| Interacting Drug | Type | Effect | Management |
|---|---|---|---|
| Thiazide diuretics (e.g., hydrochlorothiazide) | Major | Reduce renal calcium excretion, increasing risk of hypercalcemia with vitamin D | Monitor serum calcium regularly; adjust doses as needed |
| Cardiac glycosides (e.g., digoxin) | Major | Vitamin D-induced hypercalcemia increases risk of digoxin toxicity and cardiac arrhythmias | Monitor serum calcium and digoxin levels; ECG monitoring may be required |
| Orlistat | Moderate | Reduces absorption of fat-soluble vitamins including vitamin D | Take vitamin D at least 2 hours before or after orlistat |
| Cholestyramine / Colestipol | Moderate | Bile acid sequestrants reduce intestinal absorption of vitamin D | Separate doses by at least 4 hours |
| Phenytoin / Barbiturates | Moderate | Induce hepatic enzymes that increase vitamin D metabolism, reducing effectiveness | Higher vitamin D doses may be required; monitor 25(OH)D levels |
| Rifampicin | Moderate | Potent enzyme inducer that accelerates vitamin D metabolism | Monitor vitamin D levels; dose adjustment likely needed |
| Corticosteroids | Minor | May reduce calcium absorption and impair vitamin D metabolism | Consider higher vitamin D intake during long-term steroid use |
| Mineral oil / Liquid paraffin | Minor | May reduce absorption of fat-soluble vitamins with prolonged use | Avoid prolonged concomitant use; separate doses if needed |
Major Interactions
The most clinically important interactions are with thiazide diuretics and cardiac glycosides (digoxin). Thiazides reduce calcium excretion by the kidneys, meaning that when combined with vitamin D (which increases calcium absorption), there is a real risk of hypercalcemia. Patients taking both medications should have their serum calcium levels monitored regularly, typically every 3–6 months, and more frequently when starting or adjusting doses.
Digoxin has a narrow therapeutic index, and its toxicity is potentiated by elevated serum calcium levels. Since vitamin D increases intestinal calcium absorption, patients on digoxin and vitamin D need careful monitoring of both serum calcium and digoxin levels. Symptoms of digoxin toxicity include nausea, visual disturbances, and potentially life-threatening cardiac arrhythmias. If you are taking digoxin, never adjust your vitamin D dose without consulting your cardiologist or prescribing physician.
Minor Interactions
Several medications can reduce the effectiveness of vitamin D supplementation by interfering with its absorption or metabolism. Orlistat, a weight-loss medication that inhibits fat absorption, also reduces absorption of fat-soluble vitamins including vitamin D. Timing the doses at least 2 hours apart can help minimize this effect. Similarly, bile acid sequestrants such as cholestyramine and colestipol bind fat-soluble vitamins in the gut, and a 4-hour separation between doses is recommended.
Corticosteroids (such as prednisolone) used long-term can impair calcium absorption and vitamin D metabolism, which is one reason why patients on chronic steroid therapy are at increased risk of osteoporosis and are frequently prescribed vitamin D and calcium supplementation. Anticonvulsants such as phenytoin and phenobarbital induce hepatic cytochrome P450 enzymes, accelerating the inactivation of vitamin D metabolites. Patients on these medications often require higher vitamin D doses to maintain adequate serum levels.
What Is the Correct Dosage of Cholecalciferol Afortas?
The standard adult dose of Cholecalciferol Afortas is one tablet (800 IU) daily, taken with a meal. Dosage may be adjusted based on vitamin D blood levels and individual clinical needs. Always follow your doctor's prescribed dose, as requirements vary based on age, health status, and degree of deficiency.
The correct dosage of Cholecalciferol Afortas depends on several factors including the severity of vitamin D deficiency, individual patient characteristics, and the treatment goal (prevention versus treatment of established deficiency). The following dosage recommendations are based on international guidelines from the Endocrine Society, NICE/BNF, and WHO, but your doctor will determine the most appropriate dose for your specific situation.
| Patient Group | Indication | Typical Dose | Notes |
|---|---|---|---|
| Adults (19–64 years) | Prevention of deficiency | 800 IU (1 tablet) daily | Take with a meal; reassess annually |
| Adults (19–64 years) | Treatment of deficiency | 800–4000 IU daily (as directed) | Higher doses may require additional preparations; recheck levels after 3 months |
| Elderly (65+ years) | Prevention & bone health | 800–1000 IU daily | Often prescribed with calcium for fall and fracture prevention |
| Pregnant women | Maternal & fetal health | 400–800 IU daily | Do not exceed without medical supervision |
| Post-menopausal women | Osteoporosis adjunct | 800–2000 IU daily | Usually combined with calcium; per Endocrine Society guidelines |
Adults
For adult patients, the standard recommended dose of Cholecalciferol Afortas for preventing vitamin D deficiency is one tablet (800 IU) once daily. This dose is aligned with the recommendations of the Endocrine Society, which suggests 600–1000 IU daily for adults at risk of deficiency, and the BNF, which recommends 800 IU daily as a standard maintenance dose. Take the tablet with a main meal that contains some dietary fat, as vitamin D is fat-soluble and absorption increases by approximately 50% when taken with a fat-containing meal.
For patients with confirmed vitamin D deficiency (serum 25(OH)D below 20 ng/mL or 50 nmol/L), your doctor may prescribe a higher initial loading dose using additional vitamin D preparations, followed by a maintenance dose that may include Cholecalciferol Afortas 800 IU daily. Treatment of established deficiency typically involves 1600–4000 IU daily for 8–12 weeks, followed by reassessment of blood levels. The 2024 Endocrine Society guideline recommends empiric supplementation of 1000–2000 IU daily for most adults at risk.
Children
Cholecalciferol Afortas 800 IU tablets are intended for adult use. For children, vitamin D supplementation requirements are typically lower (400–600 IU daily for most age groups), and pediatric formulations such as drops or chewable tablets are more appropriate. If a pediatrician recommends Cholecalciferol Afortas for a child or adolescent, follow their dosing instructions precisely. The American Academy of Pediatrics recommends 400 IU daily for all infants and children from birth, with consideration of higher doses in those with risk factors for deficiency.
Elderly
Older adults (65 years and above) are at particularly high risk of vitamin D deficiency due to decreased skin synthesis, reduced outdoor activity, and lower dietary intake. The recommended dose for this population is 800–1000 IU daily, often in combination with calcium supplementation (1000–1200 mg of elemental calcium daily). This combination has been shown in systematic reviews and meta-analyses to reduce the risk of hip fractures and non-vertebral fractures in older adults, particularly those in residential care or with confirmed vitamin D deficiency.
A landmark Cochrane review found that vitamin D combined with calcium reduced hip fracture risk by approximately 16% in older adults. The benefit was most pronounced in institutionalized patients and those with very low baseline vitamin D levels. For ambulatory elderly patients, the evidence is more nuanced, and the 2024 Endocrine Society guideline recommends individualized assessment.
Missed Dose
If you forget to take a dose of Cholecalciferol Afortas, take it as soon as you remember on the same day. If you do not remember until the following day, skip the missed dose and continue with your regular schedule. Do not take a double dose to make up for a forgotten dose. Vitamin D has a long half-life in the body (approximately 2–3 weeks for 25(OH)D), so missing a single dose is unlikely to have any significant clinical effect on your overall vitamin D status.
Overdose
Vitamin D toxicity (hypervitaminosis D) is rare at the 800 IU dose of Cholecalciferol Afortas but can occur with chronic ingestion of very high doses, typically above 10,000 IU daily for extended periods. The toxic effects are primarily mediated by hypercalcemia. Symptoms of vitamin D overdose include:
- Gastrointestinal: Nausea, vomiting, constipation, abdominal pain, loss of appetite
- Renal: Excessive thirst (polydipsia), frequent urination (polyuria), kidney stones, and in severe cases, kidney damage
- Neurological: Confusion, drowsiness, muscle weakness, fatigue
- Cardiovascular: Cardiac arrhythmias, hypertension (in severe hypercalcemia)
- Musculoskeletal: Bone pain, joint pain
If you suspect an overdose, stop taking the medicine immediately and seek medical attention. Treatment of vitamin D toxicity involves discontinuation of the supplement, a low-calcium diet, adequate hydration, and in severe cases, medications such as loop diuretics, corticosteroids, or bisphosphonates to lower serum calcium. The European Medicines Agency defines the tolerable upper intake level (UL) for vitamin D as 4000 IU (100 mcg) per day for adults.
If you or someone else has taken a large number of tablets, or if a child has accidentally swallowed this medicine, contact your local poison control center or emergency department immediately. Bring the medicine packaging with you.
What Are the Side Effects of Cholecalciferol Afortas?
At the recommended dose of 800 IU daily, side effects from Cholecalciferol Afortas are uncommon. The most significant potential side effect is hypercalcemia (elevated blood calcium), which typically only occurs with prolonged high-dose use. Allergic reactions are very rare. Most patients tolerate vitamin D3 supplementation without any adverse effects.
Like all medicines, Cholecalciferol Afortas can cause side effects, although not everybody gets them. Vitamin D3 at the standard 800 IU daily dose has an excellent safety profile, and the majority of reported side effects are associated with long-term use at doses significantly higher than those typically prescribed. The following frequency classifications are based on data from clinical trials, post-marketing surveillance, and the Summary of Product Characteristics (SmPC) for cholecalciferol preparations.
It is important to distinguish between side effects caused directly by the vitamin D3 itself and symptoms that arise from hypercalcemia (elevated blood calcium levels) as a consequence of excessive vitamin D activity. At 800 IU daily, the risk of hypercalcemia is very low in patients with normal kidney function and no predisposing conditions.
Uncommon (affects fewer than 1 in 100 people)
- Hypercalcemia (elevated blood calcium) – particularly with higher doses or prolonged use
- Hypercalciuria (excess calcium in urine)
Rare (affects fewer than 1 in 1,000 people)
- Nausea
- Constipation
- Abdominal pain
- Diarrhea
- Dry mouth, metallic taste
- Loss of appetite
- Headache
- Muscle weakness, muscle pain
- Pruritus (itching), rash, urticaria (hives)
Very Rare (affects fewer than 1 in 10,000 people)
- Allergic reactions (hypersensitivity), including angioedema
- Nephrocalcinosis (calcium deposits in kidneys)
- Kidney stones
- Polyuria (excessive urination) and polydipsia (excessive thirst)
- Cardiac arrhythmias (associated with severe hypercalcemia)
If you develop symptoms suggestive of hypercalcemia – such as persistent nausea, vomiting, excessive thirst, frequent urination, constipation, confusion, or muscle weakness – stop taking Cholecalciferol Afortas and contact your doctor promptly. These symptoms are more likely to occur in patients also taking calcium supplements, those with impaired kidney function, or those taking doses above the recommended level.
Allergic reactions to cholecalciferol itself are extremely rare. However, allergic reactions to excipients (inactive ingredients) in the tablet formulation can occur. Seek immediate medical attention if you experience signs of a severe allergic reaction, including swelling of the face, lips, tongue, or throat, difficulty breathing, or a severe skin rash.
If you experience any side effects, talk to your doctor or pharmacist. You can also report side effects to your national medicines regulatory authority (such as the EMA in Europe, FDA in the United States, or MHRA in the United Kingdom) to help monitor the safety of medicines.
How Should You Store Cholecalciferol Afortas?
Store Cholecalciferol Afortas at room temperature (below 25°C / 77°F) in the original packaging to protect from light and moisture. Keep out of reach and sight of children. Do not use after the expiry date printed on the packaging.
Proper storage of Cholecalciferol Afortas is important to ensure the medicine retains its potency and remains safe to use throughout its shelf life. Vitamin D3 is sensitive to light, heat, and moisture, and improper storage can lead to degradation of the active ingredient, reducing the effectiveness of the medicine.
Store the tablets at room temperature, not exceeding 25°C (77°F). Keep them in the original blister pack or container to protect from light and moisture. Do not store in the bathroom, near a sink, or in other damp, warm places. Avoid exposing the tablets to direct sunlight or excessive heat, such as leaving them in a car during summer months.
Keep all medicines out of the reach and sight of children. A locked medicine cabinet is ideal. Do not use Cholecalciferol Afortas after the expiry date (EXP) stated on the carton and blister pack. The expiry date refers to the last day of that month. Once expired, return unused tablets to your pharmacy for safe disposal. Do not dispose of medicines via wastewater or household waste – ask your pharmacist about appropriate disposal methods to help protect the environment.
Do not transfer the tablets to another container, as this removes important identifying information and may expose them to conditions that accelerate degradation. If you notice any change in appearance of the tablets (discoloration, crumbling, unusual odor), do not take them and consult your pharmacist.
What Does Cholecalciferol Afortas Contain?
Each Cholecalciferol Afortas tablet contains 800 IU (20 micrograms) of cholecalciferol (vitamin D3) as the active ingredient. The tablets also contain excipients (inactive ingredients) necessary for manufacturing and stability.
The active substance in Cholecalciferol Afortas is cholecalciferol, also known as vitamin D3 or colecalciferol. Each tablet contains 800 international units (IU), which is equivalent to 20 micrograms (mcg) of cholecalciferol. Vitamin D3 is the form of vitamin D naturally produced in human skin upon exposure to sunlight, and it is considered more effective at raising and maintaining serum 25-hydroxyvitamin D levels compared to vitamin D2 (ergocalciferol).
The inactive ingredients (excipients) in the tablet serve various pharmaceutical purposes, including binding the tablet, controlling its disintegration, and ensuring stability during storage. Common excipients in cholecalciferol tablet formulations include:
- Microcrystalline cellulose – a binder and filler that gives the tablet its structure
- Lactose monohydrate – a filler (patients with lactose intolerance should be aware)
- Croscarmellose sodium – a disintegrant that helps the tablet break apart in the stomach
- Magnesium stearate – a lubricant used during manufacturing
- Silicon dioxide (colloidal) – a flow agent
- Sucrose – used in the vitamin D3 preparation for stabilization
- Modified starch – acts as a protective carrier for the vitamin D3
- Medium-chain triglycerides – fat carrier to enhance stability and absorption of the fat-soluble vitamin
- dl-Alpha-tocopherol – an antioxidant (vitamin E) to protect vitamin D3 from oxidative degradation
If you have known allergies or intolerances to any excipients, particularly lactose or sucrose, discuss this with your doctor or pharmacist before starting treatment. The exact excipient composition may vary between manufacturers and batches; always refer to the patient information leaflet included with your specific product for the most accurate and up-to-date list of ingredients.
Cholecalciferol (vitamin D3) is preferred over ergocalciferol (vitamin D2) for supplementation because studies have demonstrated that D3 is approximately 87% more effective at raising serum 25(OH)D concentrations and produces a 2–3 times greater storage of vitamin D than D2. This is why the majority of prescription and over-the-counter vitamin D supplements now contain D3.
Frequently Asked Questions About Cholecalciferol Afortas
Cholecalciferol Afortas contains vitamin D3 (cholecalciferol) 800 IU and is used to prevent and treat vitamin D deficiency in adults. It supports calcium absorption, promotes healthy bone mineralization, and may be prescribed alongside calcium supplements for osteoporosis prevention and treatment. Vitamin D also plays important roles in immune function and muscle health.
Take one tablet (800 IU) once daily with a meal that contains some fat, as vitamin D is fat-soluble and absorption is significantly improved when taken with dietary fat. Swallow the tablet whole with a glass of water. Try to take it at the same time each day to help you remember. Your doctor may adjust the dose based on your blood test results.
Vitamin D supplementation during pregnancy is generally considered safe and is recommended by most health organizations at doses of 400–800 IU daily. However, high doses should be avoided as they can cause hypercalcemia, which may be harmful to the developing baby. Always consult your doctor or midwife before taking Cholecalciferol Afortas during pregnancy or while breastfeeding.
At the recommended dose of 800 IU daily, side effects are uncommon. Rare side effects may include nausea, constipation, and elevated calcium levels (hypercalcemia). Symptoms of hypercalcemia include excessive thirst, frequent urination, nausea, and muscle weakness. If you experience these symptoms, stop taking the medicine and contact your doctor immediately.
Yes, Cholecalciferol Afortas is classified as a prescription-only medicine (Rx). While vitamin D supplements at lower doses may be available over-the-counter in many countries, Cholecalciferol Afortas requires a prescription from a doctor. This ensures appropriate monitoring of your vitamin D and calcium levels during treatment.
The duration depends on your individual needs and the reason for supplementation. For treating vitamin D deficiency, treatment typically continues for several months until levels normalize (usually 3–6 months), followed by ongoing maintenance dosing. For osteoporosis prevention, long-term daily use may be recommended. Your doctor will advise based on regular blood test results.
You can take Cholecalciferol Afortas with most supplements, but be cautious about the total vitamin D intake from all sources (food, supplements, and fortified products) to avoid exceeding safe limits. If you take a multivitamin that already contains vitamin D, account for this when calculating your total daily intake. Calcium supplements can generally be taken alongside vitamin D, as the two work synergistically for bone health. Always inform your doctor about all supplements you are taking.
References
All medical information on this page is based on peer-reviewed research, international clinical guidelines, and official drug information sources. Evidence level: 1A (systematic reviews and meta-analyses of randomized controlled trials).
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- Holick MF, Binkley NC, Bischoff-Ferrari HA, et al. Evaluation, treatment, and prevention of vitamin D deficiency: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab. 2011;96(7):1911–1930. doi:10.1210/jc.2011-0385
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