Which vitamins do we need to eat? 

There are 13 vitamins which all interact with our cell enzymes to regulate a variety of essential bodily functions. They are crucial for many of our metabolic processes, to release energy from nutrients, and in building and maintaining bones, teeth, skin, blood and many other vital body tissues.

There are two main categories of vitamins – fat-soluble and water-soluble.  Here we explain the which are the fat soluble vitamins, why you need them and where you find them in our foods.

Fat-soluble vitamins

In one sentence: Fat-soluble vitamins use the fats that we eat as a transport system to get around our body, and are stored in those fatty tissues and our liver.

The fat-soluble vitamins are A, D, E and K.  Fat-soluble vitamins can be stored in our bodies (in the liver and fatty tissues), so they don’t need to be taken every day: 2-3 times per week should be sufficient in most cases for adults.

One reason why we need fat in our diet is that the fat-soluble vitamins are transported with fats in “lipoproteins” in our blood, or with specific transport proteins because they cannot dissolve in water (or blood).  These vitamins operate in cells and their membranes. Because these vitamins can be stored in our body, excessively high intakes of them can be toxic (harmful).

Vitamin A

Why do we need Vitamin A?

Vitamin A is needed for healthy growth (e.g. bone growth) and for normal tissue development.  It is important in helping with the moisturisation of our skin and also in maintaining our mucous membranes (e.g. linings of the nose, eyes and throat) which helps to stop bacteria and viruses from entering.

Vitamin A also helps with vision, especially night vision (or when there is low light) as it helps produce rhodopsin in the retina of our eyes which is needed for night vision.  You may have heard of carrots being good for our night vision.  It’s the beta-carotene in carrots which forms vitamin A in our bodies.

It is also an antioxidant, which means that it protects against the effects of “free radicals” (which can damage healthy body cells) therefore may reduce heart disease and some types of cancer.

Vitamin A also boosts our immunity (our immune system helps protect our body by fighting against bad bacteria and viruses).

Where do we find Vitamin A in our diet?

There are two forms of Vitamin A, each form is found from different sources.

The form found in animals is known as retinol. The liver of animals is the richest source. Other rich sources are oily fish (e.g. mackerel) and dairy products (e.g. butter and milk).

The form found in plants is known as beta-carotene. It is found in green, orange, yellow and red fruits (e.g. mango and melon) and vegetables (e.g. spinach, carrot, and red pepper).

Vitamin A is stored in our liver.

Vitamin D

Why do we need Vitamin D?

Vitamin D regulates and improves the uptake of calcium and phosphate in our bodies which are needed for healthy bones and teeth.

It is very important for pregnant and breastfeeding mothers to help with the child’s bone development.  Without it, it is possible that the child will suffer from “Ricketts”

Research has shown that vitamin D is needed to activate our immune defences (this is important to fight off infection).  There is lots of discussion on this “vitamin” which is actually a hormone rather than a vitamin.

Where do we find Vitamin D in our diet?

Most of our vitamin D is made in our skin by the action of sunlight.  As little as 20 minutes a day is enough in summer.

The other way to obtain it is through our diet. A rich dietary source of vitamin D is oily fish (e.g. tuna and mackerel). Other useful sources include eggs, fortified breakfast cereals, some yogurts and fortified foods (e.g. margarine).

Vitamin E

Why do we need Vitamin E?

Vitamin E is important as a fat-soluble antioxidant, to protect cell membranes. It is also needed for effective immune function.

Deficiency is pretty uncommon because you need only a small amount and it is naturally contained in many foods.  Low levels of vitamin E may add risks of heart disease.

Where do we find Vitamin E in our diet?

Naturally found in many foods, but rich sources are within seeds and nuts, so vegetable oils and spreads which have come from pressing seeds and nuts, are very good sources.   Oily fish and most green leafy vegetables are also good sources.

Vitamin K

Why do we need Vitamin K?

Vitamin K is fairly unknown to the general public, but it is still very important.  It is necessary for normal blood clotting (healing wounds) and in the growth and in development of our bones and kidneys.

Deficiency is almost unknown. However, the blood-thinning drug, Warfarin, is known to block vitamin K action because its main aim is to prevent blood clotting.

Where do we find Vitamin K in our diet?

Widely present in foods. The richest sources are green leafy vegetables, also meats, dairy products, vegetable oils and cereals.