您可以过量服用维生素吗？

Fat-soluble vs. water-soluble vitamins

The 13 known vitamins are divided into 2 categories — fat-soluble and water-soluble ( 1 ).

Water-soluble vitamins

Water-soluble vitaminsare readily excreted from the body and not easily stored in tissues. There are more water-soluble vitamins than there are fat-soluble ones ( 2 ).

水溶性维生素包括维生素C，加上八种B维生素：

• 维生素B1 (thiamine)
• 维生素B2 (riboflavin)
• 维生素B3（烟酸）
• 维生素B5 (pantothenic acid)
• 维生素B6 (pyridoxine)
• 维生素B7 (biotin)
• 维生素B9 (folate)
• 维生素B12 (cobalamin)

由于水溶性维生素没有被储存，而是通过尿液排泄，因此即使服用高剂量，它们也会引起问题。

However, taking megadoses of some water-soluble vitamins can lead to potentially dangerous side effects.

For example, taking very high doses of vitamin B6 can lead to potentially irreversible nerve damage over time, while taking large amounts of niacin — typically in excess of 2 grams per day — can cause liver damage ( 3 ，，，， 4 ).

脂溶性维生素

Unlike water-soluble vitamins,脂溶性维生素do not dissolve in water and are easily stored in your body’s tissues ( 2 ).

There are four fat-soluble vitamins:

• 维生素A
• 维生素D
• 维生素E
• 维生素K

Given that fat-soluble vitamins can accumulate in the body, these nutrients are more likely to lead to toxicity than water-soluble vitamins.

While rare, taking too much vitamin A, D, or E can lead to potentially harmful side effects ( 5 ).

Alternatively, taking high doses of non-synthetic vitamin K seems to be relatively harmless, which is why an upper intake level (UL) has not been set for this nutrient ( 6 ).

上层摄入水平旨在表明最大剂量的营养剂量，这不太可能对普通人群中的几乎所有人造成伤害（ 7 ，，，， 8 ).

SUMMARY

水溶性维生素很容易从体内排泄，而脂溶性维生素可以储存在组织中。尽管水溶性维生素也可以这样做，但脂溶性维生素更可能引起毒性。

Potential risks of taking too many vitamins

当通过食物自然食用时，即使大量食用，这些营养素也不太可能造成伤害。

然而，当以补充形式以浓缩剂量服用时，很容易服用过多，这样做会导致负面的健康结果。

Side effects of overconsuming water-soluble vitamins

When taken in excess, some water-soluble vitamins can cause adverse effects, some of which can be dangerous.

However, similarly to vitamin K, certain water-soluble vitamins have no observable toxicity and hence no set UL.

These vitamins include vitamin B1 (thiamine), vitamin B2 (riboflavin), vitamin B5 (pantothenic acid), vitamin B7 (biotin), and vitamin B12 (cobalamin) ( 9 ，，，， 10 ，，，， 11 ，，，， 12 ，，，， 13 ).

重要的是要注意，尽管这些维生素没有明显的毒性，但其中一些可能与药物相互作用并干扰血液测试结果。因此，应谨慎使用所有营养补充剂。

以下水溶性维生素已经凝固UL，因为高剂量服用时会引起不良副作用：

• 维生素C。尽管维生素C的毒性相对较低，但高剂量of it can cause gastrointestinal disturbances, including diarrhea, cramps, nausea, and vomiting. Migraines can occur at doses of 6 grams per day ( 14 ，，，， 15 ).
• 维生素B3（烟酸）。当以烟酸的形式服用时，烟酸会导致高血压，腹痛，视力受损和肝脏损伤，每天高剂量1-3克（ 16 ).
• 维生素B6 (pyridoxine).B6的长期过度消费会引起严重的神经系统症状，皮肤病变，对光，恶心和胃灼热的敏感性，其中一些症状每天摄入1-6克（ 17 ).
• 维生素B9（叶酸）。Taking too much叶酸或叶酸in supplement form may affect mental function, negatively impact the immune system, and mask a potentially severe vitamin B12 deficiency ( 18 ).

Note that these are side effects that healthy people may experience when taking large doses of these vitamins. Individuals with health conditions can experience even more serious reactions to taking too much of a vitamin.

For example, though vitamin C is unlikely to cause toxicity in healthy people, it can lead to tissue damage and fatal heart abnormalities in those withhemochromatosis，铁储存障碍（ 19 ).

与耗费脂溶性维生素有关的副作用

Because fat-soluble vitamins can accumulate in your body’s tissues, they can cause much more harm when taken at high doses, especially over long periods.

除了维生素K的毒性潜力低外，其余三种脂溶性维生素还具有固定的UL，因为它们可能会在高剂量下造成伤害。

Here are some side effects related to the overconsumption of fat-soluble vitamins:

• 维生素A.While vitamin A toxicity, orhypervitaminosis A，，，，can occur from eating vitamin-A-rich foods, it’s mostly associated with supplements. Symptoms include nausea, increased intracranial pressure, coma, and even death ( 20 ).
• 维生素D。Toxicity from taking high doses of vitamin D supplements can lead to dangerous symptoms, including weight loss, appetite loss, and irregular heartbeat. It can also raise blood calcium levels, which can lead to organ damage ( 21 ).
• 维生素E.High-dose vitamin E supplements may interfere with blood clotting, cause hemorrhages, and lead to hemorrhagic stroke ( 22 ).

Although vitamin K has a low potential for toxicity, it can interact with certain medications, such as warfarin and antibiotics ( 6 ).

SUMMARY

Both water- and fat-soluble vitamins can cause side effects when taken in high doses, with some causing more severe symptoms than others.

Can taking too many vitamins be deadly?

Although it’s extremely rare to die from a vitamin overdose, there have been reported instances of death related to vitamin toxicity.

For example, hypervitaminosis A can be caused by taking one large dose of over 200 mg of vitamin A, or chronic use of more than 10 times the recommended daily intake ( 23 ).

维生素A toxicity may lead to serious complications, such as increased spinal fluid pressure, coma, and potentially fatal organ damage ( 23 ).

Additionally,服用大量维生素D-more than 50,000 IU daily — over long periods can lead to high blood levels of calcium (hypercalcemia), which can lead to death ( 24 ).

对其他维生素的过量服用同样会导致潜在的致命副作用，例如肝脏损害。

A case report found that taking very high doses of over 5 grams of extended-release niacin can lead to metabolic acidosis, a buildup of acid in body fluids, as well as acute liver failure — both of which can be fatal ( 25 ).

Keep in mind that these potentially deadly side effects are associated with taking exceptionally high doses of vitamins. Even so, caution should always be taken when consuming any dietary supplement.

总结

在极少数情况下，服用极高剂量的某些维生素可能导致致命并发症。

如何安全服用维生素

The best way to get the nutrients you need is by consuming awell-rounded diet。但是，由于多种原因，许多人需要补充维生素。

Age, genetic disorders, medical conditions, and diet are all factors that can increase the need for certain nutrients.

Fortunately, vitamins are typically safe to take as long as they are used responsibly.

The following chart outlines both the recommended daily intake (RDI) and tolerable upper intake levels (UL) for fat-soluble and water-soluble vitamins ( 6 ，，，， 9 ，，，， 10 ，，，， 11 ，，，， 12 ，，，， 13 ，，，， 14 ，，，， 15 ，，，， 16 ，，，， 17 ，，，， 18 ，，，， 20 ，，，， 21 ，，，， 22 ):

Due to potential toxicity, it’s not recommended to consume more than the tolerable upper intake levels set for the nutrients listed above.

请记住，在某些情况下，您的医疗保健提供者可能会建议您为某些营养素纠正缺乏症而不得超过UL。

For example,维生素D缺乏are often treated with high-dose vitamin D injections or supplements that deliver over 50,000 IU of vitamin D, which is much more than the UL ( 26 ).

尽管大多数补充瓶都提供了有关每天需要多少维生素的建议，但需求因人而异。

如果您对维生素剂量有疑问，最好咨询医学专家。

SUMMARY

Some vitamins have set ULs to prevent potential toxicity. It’s best to consult your healthcare provider if have questions regarding proper vitamin dosing.

The bottom line

Althoughvitamin supplementsare safely consumed by many people on a daily basis, it’s possible to take too high of a dose, which can result in adverse side effects.

Overdosing on certain vitamins can lead to serious complications and, in rare circumstances, even death.

由于这些原因，如果您对适当的给药疑问，请负责任地使用维生素并咨询可信赖的健康专业人员。