What happens when you overdose on vitamins and minerals?

Taking a big variety of supplements? Make sure that you don't exceed your tolerable limit.
Taking a big variety of supplements? Make sure that you don't exceed your tolerable limit.

Ever wondered what happens when your body is overloaded with vitamins and minerals

Many of the foods we consume are enriched with vitamins and minerals. On top of that, we also believe that it's good for our health to take supplements.

But without checking what’s on the label and if you take more than one supplement, you can easily exceed your daily recommended dose, which can lead to problems. It is, however, unlikely that you will exceed your recommended daily allowance (RDA) by obtaining vitamins and minerals from food.

Here’s what happens when you overdo it with certain vitamins and minerals:

1. Vitamin C

What it is: The most common nutritional form of vitamin C, L-ascorbic acid, is water-soluble. Our bodies don’t produce vitamin C, which means that we need to get vitamin C from our food or supplements.

Unlike fat-soluble vitamins, vitamin C doesn’t get stored in the body and any excess will usually be flushed out with your urine. Excessive quantities can, however, accumulate in tissue, which may lead to problems.

What happens to your body: Too much vitamin C can cause irritation of the stomach, leading to gastrointestinal problems such as nausea and diarrhoea. In some cases, a skin rash may develop.

Healthy amount: For adults, the daily recommended dose of vitamin C is between 65mg and 90mg. A tolerable limit of vitamin C is 2000 mg – anything above that may cause issues.

2. Iron

What it is: Iron is a vital mineral which plays a part in the formation of our red blood cells. Without iron, the body can’t produce red blood cells, which transports oxygen to our organs. Haem iron is obtained from red meat and is absorbed faster in the body, while non-haem iron is obtained from plant sources.

What happens to your body: Excess iron is stored in the organs such as the pancreas, liver, and heart. Unlike some vitamins and other nutrients, a large dose of iron can’t be excreted through urine or faeces and will accumulate in the body tissue, leading to nausea, diarrhoea, liver damage, dehydration and even coma in severe cases.

Healthy amount: The recommended daily intake of iron for men between ages 19 and 50 is 8mg, and 18mg for women in the same age group. The tolerable limit for adults is 45mg a day.

3. Vitamin A

What it is: Vitamin A is an antioxidant, essential for good eyesight, healthy skin and immune system and is fat-soluble. Most of the vitamin A in your body is stored in the liver and other body tissues for later use. There are two types of vitamin A: preformed vitamin A, which is obtainable through meat and seafood, and provitamin A, which is obtained through plant foods.

What happens to your body: Too much preformed vitamin A (as a result of supplements or medicines) can lead to dizziness, nausea, headaches, coma and even death. An excess of preformed vitamin A in pregnant woman may cause birth defects. High amounts of provitamin A in the form of beta-carotene can turn the skin orange, but this is not a serious symptom. Dry lips are usually the first sign of vitamin A overdose, followed by dryness of the nasal mucosa and eyes.

Healthy amount:  The tolerable limit for adults over 19 is 10 000 IU (international units) while the daily recommended dose differs throughout life stages. Read more in detail here

4. Zinc

What it is: Zinc is a mineral distributed in the body’s organs, tissues and fluids, and is crucial for the proper function of more than 70 enzymes. Although this mineral isn’t stored in the body for long and it’s important to replenish your zinc levels regularly, zinc poisoning through the overuse of supplements can occur.

What happens to the body: When you take too much zinc, you may experience symptoms such as nausea, headaches, vomiting and diarrhoea.

Healthy amount: The recommended dose for men over the age of 19 is 11mg and 8mg for women. The tolerable limit is 40mg. 

Important disclaimer: This article is meant to be informative and general recommendations were used. Every person is unique, and different life stages and medical conditions will influence your need for different vitamins and minerals. Speak to your doctor who will be able to guide you regarding supplements. Also remember that supplements may interfere with some medications.

Image credit: iStock

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