What are Vitamins and Why are They Important?
Vitamins are molecules which the body needs in small amounts. They are also essential for multiple processes in the body. They are classified as micronutrients, which means the body only needs a small quantity to function properly. This can range from milligrams to micrograms per day. The majority of vitamins cannot be synthesized by the body, so you will need to get them from your diet. The exceptions to this rule are Vitamin D (synthesized by sunlight on to the skin) and Niacin (B Vitamin which can be synthesized from tryptophan, an amino acid).
How Does Your Body Absorb Vitamins?
Vitamins are absorbed on the basis of the molecule structure. They fall into two different categories: water-soluble and fat-soluble vitamins.
You can find water-soluble vitamins in the watery portions of the food you eat. They are absorbed directly into the bloodstream once the food has been broken down. As your body is mostly water, water-soluble vitamins circulate the body easily. Therefore the kidneys are constantly regulating the level of these vitamins. If you have too much, your kidneys will push them out of the bloodstream and into the urine.
The Water-Soluble Vitamins are the B Vitamins and Vitamin C
Fat-soluble vitamins, on the other hand, you absorb differently. They enter the blood via the lymph channels in the intestinal wall and many of them have to be escorted by carrier proteins. Fat-soluble vitamins do have the ability to be stored within the liver or in fat cells too. So if the body requires the vitamin, it can be easily accessed without needing further food intake. If you have too many of these vitamins, this can lead to the body storing too much. This in turn can lead to toxicity, as the kidneys do not have clear access to the fat-soluble vitamins to remove from the blood.
The fat-soluble vitamins are Vitamin A, Vitamin D, Vitamin E and Vitamin K.
Do They Actually Work?
There has been extensive research in the benefit of taking multivitamins. Unfortunately, there has not been a definitive conclusion that taking multivitamins can improve your body’s health or prevent illness.
Examples of Research:
- An analysis of research involving 450,000 people, which found that multivitamins did not reduce risk for heart disease or cancer.
- A study that tracked the mental functioning and multivitamin use of 5,947 men for 12 years found that multivitamins did not reduce risk for mental declines such as memory loss or slowed-down thinking.
- A study of 1,708 heart attack survivors who took either a high-dose multivitamin or placebo for up to 55 months. Rates of later heart attacks, heart surgeries and deaths were similar in the two groups.
It was concluded that eating a healthy diet and maintaining a healthy weight is more fundamental to protect the body from illness than taking a daily vitamin. The exceptions to this rule are young women who are childbearing – all women of reproductive age are recommended to take 400 micrograms of folic acid daily. When a woman takes the vitamin before and during early pregnancy, folic acid can help prevent neural tube defects in babies .
If you feel that you are unwell, and the symptoms link to a deficiency of a vitamin, you should consult your GP first. They can do a blood test to determine if you need to change your diet or if they need to prescribe further supplements.
The bottom line is that taking vitamin supplements can aid the body in primary functions. However, medical professionals recommend eating a well-balanced diet, as the diet can provide further benefits to maintain homeostasis.