One wouldn’t take an antibiotic without being sick, but for some reason countless individuals are taking vitamins despite having no deficiencies. While in most cases this is simply a waste of money and the extra vitamins are simply flushed out in urine, for those who take large quantities of unnecessary vitamins, the health consequences are serious. But just how many vitamins does it take to kill a person?

Vitamins are organic compounds needed in small quantities to sustain life, Medical News Today reported. We normally get the necessary amount from our daily diet, but sometimes, due to dietary restraints, individuals will develop vitamin deficiencies. However, Marissa Puleo, a registered diectian working in Pennsylvania, told Medical Daily that one needs to be careful with vitamin intake.

"Taking too many vitamins and supplements does have negative consequences," Puleo said. Although many water soluable vitamins are excreted when too much is taken, others remain in the body. "These vitamins can reach toxic levels and cause adverse side effects."


Anemia is a condition when one doesn’t have enough healthy red blood cells to carry adequate oxygen to your tissues. It’s more common among women and can cause symptoms such as fatigue and feeling weak. Do not self-diagnose your anemia and especially don’t self-treat it. Unnecessary iron can accumulate in the body and even rise to toxic levels. Taking more than the recommended amount of iron over time can cause brown skin discoloration, an enlarged liver or spleen, abdominal pain, congestive heart failure, an irregular heart rhythm, and insulin dependent diabetes, just to name a few.

Excessive amounts of iron are especially common in pregnant women. A recent study by a team of doctors in India found that excessive iron dosage among healthy non-anemic women could lead to problems, including low birth weight, premature birth, and poor growth of the baby while in the womb.

Lisha Shastri, a final year MBBS student and one of the lead researchers on the study, explained to the Bangalore Mirror that her findings suggest the need for women without anemia to stay away from additional iron supplements, especially during pregnancy.

“Iron in high daily doses could be responsible for cellular damage through oxidative stress,” Shastri said. “This needs to be balanced with sufficient anti-oxidants, which can be obtained from fruits rich in vitamin C. The dosage of iron varies from one individual to another, which is why there cannot be a standardized dosage that can be fixed for everyone."

Often women who are menstruating or women who partake in particularly strenuous sports, such as distance runners, are at greater risks for iron deficiencies, but there are many ways to introduce more iron into your diet without using supplements. Meat and eggs are particularly high in iron, and for vegetarians, beans and tofu are also great sources of the vitamin.

How Much Can Kill You

As reported by Livestrong, a one-time overdose of iron can kill you. The limit for iron intake is put at around 20mg of elemental iron per kilogram of body weight. Any more than this and a person may experience abdominal pain, persistent vomiting, rapid breathing, and coma.

A one-time overdose of iron can prove fatal. US CPSC CC BY 2.0

Vitamin C

Vitamin C is arguably one of the most popular and widely recognized of all vitamins. Deficiencies of vitamin C can cause tooth lose, acne, fatigue, and even death. Taking vitamin C to help fight off a cold is also recommended by doctors. Still, despite all this there is still such a thing as having too much of it.

Unless you have a cold or it’s recommended by doctors, you’re safer getting your daily dose of vitamin C in food. Citrus fruits, berries, and vegetables such as broccoli and Brussels sprouts have high levels, the University of Maryland Medical Center advises. Also, many foods such as cereal and drinks are actually fortified with vitamin C, so chances are you’re probably getting the recommended amount without even realizing it.

How Much Can Kill You

The good news is that overdoing it on vitamin C will not kill you. Around 2,000mg of vitamin C is considered the limit. For those who consume this amount in a day, symptoms such as vomiting, heartburn, headache, insomnia, and kidney stones may follow. However, anything over 1,000mg can lead to diarrhea.

Eating fruit such as oranges is an easy and natural way to get vitamin C. Photo courtesy of José Luis Sánchez Mesa CC BY 2.0

Vitamin A

Vitamin A is known for promoting good vision but also helps to form and maintain healthy skin, teeth, skeletal and soft tissue, and the mucous membrane. Medline Plus reports that individuals who do not get enough vitamin A are more likely to get infectious disease and vision problems.

A high dose of vitamin A can cause the following side effects: nausea, vomiting, diarrhea, loss of appetite, tiredness, headaches, dizziness, blurred vision, poor muscle coordination, itchiness and scaling of the skin, bone pain, hair loss, irregular menstruation in women, osteoporosis, and temporary or permanent liver damage. High doses of vitamin A are also known to increase the risk of lung cancer in smokers, the BBC reported.

Acute hypervitaminosis is a severe condition resulting from consuming too much vitamin A during a short period of time. It was first documented in arctic explorers who unknowingly consumed vitamin A-rich livers of many artic animals, such as seals, husky dogs, and yes, even the polar bear. The symptoms of the extremely unpleasant condition are loss of skin and hair, liver damage, hemorrhage, coma, and even death.

How Much Can Kill You

The problem with vitamin A is that unlike other vitamins, excess amounts don’t flush out in urine but rather build up in the liver. However, unless you’re eating polar bear liver, it’s unlikely you’ll consume enough vitamin A to kill you. According to the San Francisco Gate, 3,000mg of vitamin A a day is the limit and any more can have unpleasant consequences. To put that into perspective, that’s around 79 to 115 chickens eggs, according to How Stuff Works.

vitamin A
Ingesting too much vitamin A can cause severe skin loss and even coma. Photo courtesy of Colin Dunn CC BY 2.0

Gummy Multivitamins

In an article published by BuzzFeed earlier this year, Dr. Ken Spaeth from North Shore Long Island Jewish Health System explained that in high quantities those gummy fruity vitamin supplements are no good for your health.

“On the whole, it would be a very bad idea and potentially dangerous to take excessive amounts of multivitamins, even tasty ones such as the gummy variety,” Spaeth said. “While the recommended amounts pose virtually no risk, consuming an entire bottle of vitamins can cause permanent and serious harm,” Spaeth said. “The body is not able to clear excessive amounts of this type quickly, and the subsequent buildup of high levels can inflict an array of injury to various organ systems, including the brain.”

How Much Can Kill You

The article noted that, theoretically, consuming the entire bottle of gummy supplements in one sitting could kill you; however, this is largely dependent on the type of vitamins present.

We know they taste good, but please don't eat the whole bottle in one go. Photo courtesy of martakat83 CC BY 2.0

In conclusion, Puleo gave Medical Daily one rule of thumb to go by when it comes to monitoring your vitamin intake: "Eating a varied nutrious diet is the best source of any vitamin or mineral. If you want to increase vitamin C, it's sggested to eat more citrus rather than take a vitamin C pill."