Is too many vitamins good or bad for Cancer?

Vitamins and minerals are considered crucial nutrients as they help the body perform of a number of functions. There’s a subtle line between having enough of these micronutrients (as per the recommended
allowance, which is good) and getting too much of them (which can end up causing harm). The easiest method to ensure adequate intake of the vitamins and minerals required is to eat a nutritious diet which
contains all the food groups in right amounts.

Vitamins are of two types : water soluble and fat soluble vitamins. Both the types play different roles in the body.

Water soluble vitamins :

Water soluble vitamins comprise of the B-vitamins and vitamin C. Water-soluble vitamins are found in the watery parts of the food. As food is broken down during digestion or a supplement dissolves, they are absorbed straight into the blood.
Because water makes up a good portion in the body, many of the water-soluble vitamins move freely and are absorbed easily. The kidneys constantly regulate the amounts of water-soluble vitamins in the body by excreting surplus amounts in urine.

They perform the following functions in the body :

Release energy. Several B vitamins are essential components of coenzymes (molecules that assist enzymes) that aid in the release of energy from food.

  • Produce energy. Thiamin, riboflavin, niacin, pantothenic acid, and biotin help in energy production.
  • Help build protein and cells. Vitamins B6, B12, and folic acid help cells multiply by metabolizing amino acids (protein building blocks).
  • Make collagen. Vitamin C aids in the formation of collagen, which helps in wound healing, maintains blood vessels.
  • Contains antioxidants and reduce free radical damage in the body.
  • Helps build stronger immunity.
  • Folic acid prevents birth defects.
  • Maintains strong teeth and bones.

Fat soluble vitamins

Vitamins A, D, E, and K are fat-soluble vitamins. They can be found in fat-containing meals. These vitamins are absorbed in the same way that dietary fats are. These vitamins are used by the body and any excess amount is stored in the liver and fat tissues. These five vitamins help maintain the health of the eyes, skin, lungs, gastrointestinal tract, and nervous system. The other functions are :

Vitamins A, D, K assist in bone formation.

Vitamin A promotes growth, maintenance and healthy vision. It
may also help prevent cataract.

They have antioxidant properties and protect the body against
free radical damage.

Help support the immune system.

Vitamin K is responsible for blood clotting. Apart from this it helps
in maintaining cardiac health and regulate the amount of calcium
in blood.

Risks associated with over-consumption of vitamins :

People who eat a diet high in fruits, vegetables, nuts, whole grains, and fish have a decreased risk of various lifestyle illnesses, including heart disease, stroke, diabetes, and cancer. Trials examining the efficacy of specific vitamins or minerals as supplements, on the other hand, have largely revealed that they have
little effect on health.
The major exception may be fish oil supplements, which have been shown in certain studies to reduce the risk of heart disease and perhaps vitamin D deficiency. When consumed under the recommended dietary values, the vitamins are beneficial and carry out many roles in the human body. However, overdoing on these vitamins has the potential to cause harm instead of doing any good. These nutrients are unlikely to cause damage when
eaten naturally through foods like fresh fruits and vegetables , even in excessive amounts. But, when taken in supplement form in concentrated amounts, it’s easy to exceed the recommended dosage, which might have severe health consequences.

According to a study in US, over the counter multivitamins and dietary supplements when taken in larger amounts can increase the risk of developing cancer and cardiac diseases. The University of Colorado research examined at multiple trials involving thousands of patients over the course of a decade and found that those who took more vitamins and minerals were more likely to develop health complications.

Vitamin Supplement overdose

Vitamin Toxicity

Taking high doses of vitamin supplements may lead to hypervitaminosis and even toxicity in the body. Hypervitaminosis is a condition characterized by unusually high vitamin storage levels, which can lead to toxicity. Fat-soluble vitamins (D and A) are the most common cause of hypervitaminosis because they are retained in the body for longer than water-soluble vitamins.
Toxic levels of vitamins are usually caused by a high supplement intake, which does not necessarily come from natural sources, but rather a combination of natural, derived vitamins and enhancers (vitamin boosters). A high consumption of highly fortified foods can also induce fat-soluble vitamin toxicity, although natural foods in moderate amounts rarely supply excessive vitamins.

Over-consumption of vitamins and the risk of developing cancer

According to the University of Colorado, taking more beta carotene than the recommended amount — a supplement marketed as an immune system booster – increased the risk of lung cancer and heart disease by up to 20%. Consuming fruits and vegetables rich in carotenoids and following a balanced diet can help in reducing cancer risk however on the other hand, the supplemental form of beta-carotene shows strong evidence for adverse effects (ie, excess lung cancer incidence and overall mortality) particularly in smokers.
A folic acid supplement, which is supposed to prevent precancerous polyps in the colon, actually increased the incidence of cancerous polyps among users when compared to those who got a placebo, according to the research.


There is no substitution for a good, healthy and nutritious diet. It’s always best to go for natural foods in order to complete your nutritional intake. Eating a diet rich in various colorful fruits and vegetables, seasonal and local food and grains can help to attain a healthy, disease free living and also help in reducing the risk of cancer. The cancer diet plan includes the necessary food groups in appropriate proportions to attain good recovery and health. If taking supplements, always take the correct dosage, do not consume more than the
recommended dietary allowance or daily value. The dietary supplements usually have several times more than recommended daily dosages of vitamins and minerals involved which is why people who consume dietary supplements in excess or more than required are at a higher risk of developing cancer.