維生素 D3 - 用途、副作用、和健康益處

use

Vitamin D (ergocalciferol-D2, cholecalciferol-D3, alfacalciferol) is a fat-soluble vitamin that helps the body absorb calcium and phosphorus. Getting the right amounts of vitamin D, calcium, and phosphorus is important for building and maintaining strong bones. Vitamin D is used to treat and prevent bone diseases (eg, rickets, osteomalacia). The body produces vitamin D when the skin is exposed to sunlight. Sunscreen, protective clothing, limited sun exposure, dark skin, and age may prevent getting enough vitamin D from the sun. Vitamin D and calcium can be used to treat or prevent bone loss (osteoporosis). Vitamin D is also used with other medications to treat low calcium or phosphate levels caused by certain conditions (such as hypoparathyroidism, pseudohypoparathyroidism, familial hypophosphatemia). It is used in kidney disease to keep calcium levels normal and allow bones to grow properly. Breastfed babies can take vitamin D drops (or other supplements) because breast milk usually contains lower amounts of vitamin D.

How to use Vitamin D3

Take vitamin D by mouth as directed. Vitamin D is most effective when taken with food, but it can be taken with or without food. Alfacalcidol is usually taken with food. Follow all directions on product packaging. If you have any questions, ask your doctor or pharmacist.

If your doctor has prescribed this medication, take it as directed. Your dosage is based on your medical condition, amount of sun exposure, diet, age, and response to treatment.

If you are using the liquid form of this medication, carefully measure the dose using a special measuring device/spoon. Do not use a household spoon as you may not get the correct dose.

If you are taking chewable tablets or wafers, chew the medicine thoroughly before swallowing. Do not swallow the wafer whole.

If you are taking the instant-dissolve tablets, dry your hands before handling the medicine. Place each dose on your tongue, allow to dissolve completely, then swallow with saliva or water. You do not need to take this medication with water.

Certain medications (bile acid sequestrants such as cholestyramine/colestipol, mineral oil, orlistat) can reduce vitamin D absorption. The doses of these drugs should be taken as far apart as possible from the vitamin D dose (at least 2 hours apart, and longer if possible). If you also take these other medications, taking vitamin D before bed may be the easiest way. Ask your doctor or pharmacist how long you should wait between doses, and get help finding a dosing schedule that works for all your medications.

Take this medication regularly to get the most benefit. To help you remember, if you take it once a day, take it at the same time each day. If you are taking this medication only once a week, remember to take it on the same day each week. It may be helpful to mark your calendar with reminders.

If your doctor has recommended that you follow a special diet (such as a diet high in calcium), it is important to follow this diet to get the most benefit from this medication and to prevent serious side effects. Do not take other supplements/vitamins unless directed by your doctor.

side effect

Normal doses of vitamin D usually have no side effects. If you experience any unusual reactions, contact your doctor or pharmacist immediately.

If your doctor has directed you to use this medication, remember that your doctor has judged that the benefits to you are greater than the risks of side effects. Many people who use this drug do not experience serious side effects.

Too much vitamin D can lead to harmfully high calcium levels. Tell your doctor right away if you have any symptoms of high vitamin D/calcium levels: nausea/vomiting, constipation, loss of appetite, increased thirst, increased urination, mental/mood changes, unusual tiredness.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash/swelling of tongue (especially of face/itching) dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

Precaution

Before taking vitamin D, tell your doctor or pharmacist < ai=4 > if you are allergic to it; or to other vitamin D products (such as calcitriol); or if you have any other allergies. This product may contain inactive ingredients (e.g. peanut/soy) that may cause allergic reactions or other problems.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: high calcium/vitamin D levels (hypercalcemia/hypervitaminosis D), difficulty absorbing nutrients from food (malabsorption syndrome symptoms), kidney disease, liver disease.

Liquid products, chewable or dissolving tablets may contain sugar and/or aspartame. Liquid products may also contain alcohol. Caution is advised if you have diabetes, liver disease, phenylketonuria (PKU), or any other condition that requires you to limit/avoid these substances in your diet. Ask your doctor or pharmacist about using this product safely.

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, over-the-counter drugs, and herbal products).

During pregnancy, vitamin D doses above the recommended dietary intake should be used only when clearly needed. Discuss the risks and benefits with your doctor.

interactive

Drug interactions may change how your medicines work or increase your risk of serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Some products that may interact with this drug include: burosumab, phosphate binders.

Check the labels on all prescription and over-the-counter/herbal products (e.g., antacids, laxatives, vitamins) because they may contain calcium, magnesium, phosphates, or vitamin D. Ask your pharmacist how to use these products safely.

Vitamin D is very similar to calcitriol. Do not use medicines containing calcitriol when taking vitamin D.

This vitamin may interfere with certain laboratory tests (such as cholesterol tests), possibly causing false test results. Make sure lab personnel and all doctors know you use this vitamin.

excess

notes

Laboratory and/or medical tests (such as calcium/magnesium/phosphorus levels) should be done while you are taking this medication. Keep all medical and laboratory appointments. Please consult your doctor for more details.

Foods rich in vitamin D include fortified dairy products, eggs, sardines, cod liver oil, chicken liver and fatty fish.

Missed dose

If you miss a dose, take it as soon as you remember. If it is near the time of your next dose, skip the missed dose. Take your next dose at your normal time. Don't double your dose just to catch up.

storage

Store vitamin D products (except alfacalcidol) at room temperature, away from light and moisture. Do not store in bathroom. Store alfacalcidol drops in the refrigerator. Do not freeze. Keep all medicines away from children and pets.

Health Benefits of Vitamin D3

Vitamin D3 (cholecalciferol) has several health benefits, including helping the body absorb calcium. Foods such as fish, beef liver, eggs, and cheese naturally contain vitamin D3. The skin also produces it after exposure to ultraviolet (UV) radiation from the sun.

Vitamin D3 supplements may also be used for general health, as well as to treat or prevent vitamin D deficiency.

Vitamin D3 is one of two types of vitamin D. Its structure and source are different from vitamin D2 (ergocalciferol).
This article explains exactly what vitamin D supplements do and the advantages/disadvantages of vitamin D3. It also lists other great sources of vitamin D3.

Why Vitamin D is needed

Vitamin D, also known as calciferol, is a fat-soluble vitamin (i.e., a vitamin that is broken down by fats and oils in the gut). It is often called the "sunshine vitamin" because the D3 type is naturally produced in the body after exposure to sunlight.

Vitamin D has many functions in the body, including:

  • bone growth
  • bone remodeling
  • regulation of muscle contraction
  • Convert blood sugar (sugar) into energy

Insufficient vitamin D intake can lead to a range of health problems, including:

  • growth retardation in children
  • rickets in children
  • Osteomalacia (bone mineral loss) in adults and adolescents
  • Osteoporosis (osteoporosis, osteoporosis) in adults

How do I know if I need more vitamin D?

If you don't get enough vitamin D to meet your body's needs, you are considered to be vitamin D deficient. This can be diagnosed through a blood test.

However, the U.S. Preventive Services Task Force does not recommend routine vitamin D screening for adults without symptoms of deficiency.

Not all people with low vitamin D levels develop symptoms. People who do this may notice:

  • muscle and/or bone pain
  • muscle weakness
  • History of fractures
  • muscle twitching

If you suspect you may be vitamin D deficient, ask your health care provider to test your blood levels or do an at-home test.

There are many causes of vitamin D deficiency, including diseases or disorders that limit fat absorption and the breakdown of vitamin D in the intestines. Therefore, you are at greater risk for vitamin D deficiency if you:

  • Celiac disease
  • Crohn's disease
  • cystic fibrosis
  • gastric bypass surgery
  • Liver disease
  • Malnutrition
  • obesity
  • ulcerative colitis

The elderly, those who are housebound, or those with dark skin are also more likely to be deficient in vitamin D.
Vitamin D deficiency affects nearly 50% of the world's population.
Both vitamins D2 and D3 can be used to treat this condition, with vitamin D3 usually being preferred.

Vitamin D3 vs. Vitamin D2

Vitamin D2 and vitamin D3 are chemically similar and are well absorbed in the intestines. Their significant differences lie in their origin:

  • Vitamin D2 is found naturally in mushrooms, including shiitake, portobello, and crimini mushrooms. When these mushrooms are exposed to UV radiation, the vitamin D content increases.
  • Vitamin D3 occurs naturally in animals and animal-derived products such as milk. It is also synthesized directly in the skin when it is exposed to ultraviolet B (UVB) radiation.

In addition to the fact that vitamin D3 is probably easier to get in your daily diet (unless you're a vegetarian or vegan), it turns out that vitamin D3 is superior to vitamin D2 in two other important ways:

  • Vitamin D3 has better bioavailability, which means more of the vitamin enters the bloodstream and can be used by the body
  • Vitamin D3 has a longer half-life, which means it stays in the circulation longer

The downside is that vitamin D3 in supplements has historically been synthesized using lanolin derived from wool. This makes it unsuitable for those who choose to avoid animal products.

Nonetheless, some manufacturers have been able to synthesize vitamin D3 from algae and lichens.

Vitamin D3 for people without a deficiency

In addition to being used to treat vitamin D deficiency, vitamin D3 may also provide health benefits to certain people without vitamin D deficiency, especially those with high blood pressure or osteoporosis.

hypertension

High blood pressure, commonly called hypertension, is a cardiovascular disease common in people with vitamin D deficiency.

Recent research suggests that vitamin D3 may help lower blood pressure in people with high blood pressure and vitamin D deficiency, as well as in some people who only have high blood pressure.

According to a 2019 review of studies involving 1,687 people in the journal Medicine, vitamin D3 can significantly reduce systolic blood pressure ("peak") in people over 50 and obese.

This is important because over time, isolated systolic hypertension increases the risk of stroke, heart disease, and chronic kidney disease.

osteoporosis

Osteoporosis is a common consequence of long-term vitamin D deficiency, so common sense holds that vitamin D supplements may help prevent or slow the progression of this common, aging-related bone disease. There is some evidence to support this claim.

A 2013 study from the University of Western Australia found that vitamin D3 significantly reduced the incidence of hip fractures in nursing home residents over the age of 70. Additionally, low-dose vitamin D3 (400 IU) also increases bone density in the femur (thigh bone).

Sources of Vitamin D3

Whether you are deficient or simply trying to meet the recommended daily allowance (RDA) of vitamin D, you can get enough vitamin D3 from animal foods, dietary supplements, and sun exposure.
Dietary Sources Food is always the first source of vitamin D. Here are some of the best dietary sources to supplement your vitamin D3 intake:

food IU portion size % recommended daily intake
beef liver 42 3 ounces 5%
butter 9 1 tablespoon 1%
cereals 80 1-1/2 ounces 10%
cheese 12 1 oz 2%
cod liver oil 1,360 1 tablespoon 170%
yolk 44 1 egg yolk 6%
fresh salmon Chapter 570 3 ounces 71%
halibut Chapter 384 1/2 fish fillet 48%
mackerel 360 1/2 fish fillet 45%
milk, fortified 120 1 cup 15%
sardine 46 2 fish 6%
trout Chapter 645 3 ounces 81%
tuna 40 3 ounces 5%

Some juice, dairy, margarine and plant milk manufacturers also add vitamin D3 to increase the nutritional value of their products.

supplements

Although supplements are convenient, they should never be your primary source of vitamin D (or any nutrient). They really only apply if you're not getting enough from your diet.

Vitamin D3 is readily available in supplement form and sold in capsules, softgels, gummies, and drops. Most medications are formulated in higher doses than you need each day (2,000 to 10,000 international units), but this is not a problem because only a portion is absorbed. The rest will be excreted in the urine.

Talk with your healthcare provider about the dosage that's best for you based on your age and medical history.

sun exposure

Vitamin D3 is unique in that (unlike vitamin D2) you can get it from sunlight.

When exposed to UVB light, an organic compound in the skin called 7-dehydrocholesterol is activated and begins to produce vitamin D3. The rate of production may vary based on age and skin color, with older adults and people with darker skin tones benefiting the least.

Sunscreen can also reduce the production of UV rays by blocking both types.

Getting a little sun exposure every day can help maintain your vitamin D levels, but given the risk of skin cancer, it's not the safest or most reliable way to get it.

possible risks

Vitamin D3 is generally considered safe, but in rare cases, it can cause toxic effects if too much is taken. This is called hypervitaminosis D.

Due to vitamin D toxicity, the balance of minerals such as calcium and potassium can be disrupted. This can lead to a condition called hypercalcemia, in which too much calcium builds up in the body. This may cause the following symptoms:

  • Stomach discomfort
  • nausea
  • Vomit
  • constipate
  • bone pain
  • muscle weakness
  • increased risk of fractures

Vitamin D poisoning was common in the 1940s, when daily doses of 200,000 to 300,000 IU were often recommended to treat chronic diseases such as tuberculosis and rheumatoid arthritis.

Today, vitamin D intoxication is considered a rare condition.

Recent studies indicate that daily doses of 20,000 IU of vitamin D3 are tolerated by adults with no signs of toxicity.

generalize

Vitamin D helps you absorb calcium and phosphate from food. It's important for bone and muscle strength and immune function, and may have other benefits, such as helping to prevent inflammatory diseases.

There are two types; Vitamin D3 is used in the body more efficiently than Vitamin D2. You can get vitamin D from food or supplements, and your body can produce D3 when exposed to sunlight.

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