Vitamins and Minerals – Underutilized but Essential

Vitamins and minerals are essential nutrients to the health and normal functioning of the human body. They play extremely important roles in nearly every bodily process, as well as the overall health of all cells and tissues. However, as important as they are, these micronutrients are often ignored or forgotten about. Everybody needs the minimum requirement of these important nutrients, but athletes like us who regularly train hard need even more to make sure we recover effectively and limit the stress imposed on our bodies.  Here’s what you need to know about the functions and sources of some of the most important micronutrients.

Vitamin A

Vitamin A plays numerous important functions in the body. It is a powerful antioxidant that provides strong support to our immune systems, it is extremely important in the maintenance of good vision, and also helps to keep to the skin and other body lining healthy. A deficiency in vitamin can be easily rectified through some simple changes in the diet. Liver, particularly turkey, is one of the highest sources of vitamin A available. So much so that 100g of turkey liver can provide up to almost 900% of the daily recommended intake of vitamin A. It is even speculated that polar bear livers contain so much vitamin that they would be toxic to humans. Other foods such as oily fish (mackerel, salmon, and sardines), green leafy vegetables (spinach, kale, broccoli), carrots, and sweet potatoes rank highly on the list high vitamin A foods. Even foods such as eggs, cheese or milk which although not particularly high in vitamin A are consumed in such high quantities in Western countries that they are important sources of this valuable vitamin. Supplementing with cod liver oil has been popular for a very long time for its numerous benefits, and actually ranks highest on the list on vitamin A containing foods, which makes it an excellent option for those who struggle through diet alone.

Vitamin B12

Vitamin B12 is important for many essential processes including making red blood cells, brain and nervous system health, and releasing energy from food. Vitamin B12 is primarily found in animal products such as meat, salmon, cod, milk, cheese and eggs which can easily meet the minimum requirements for an individual. However, vegetarians and especially vegans may struggle to obtain sufficient quantities as plant based products are typically very poor in vitamin B12 quantities. For these populations, food products such as cereals, soya drinks, or yeast extracts (e.g. Marmite) fortified with B12 will need to be included in the diet to make up for this. However, vitamin B12 can found in sufficient quantities in multi-vitamins of B vitamin complexes if the diet is still lacking.

Vitamin C

Vitamin C is a powerful antioxidant that is important in protecting cells from damage, healing wounds, and keeping connective tissue healthy to support the stability and structure of organs. Vitamin C is found in the vast majority of fruits and vegetables in varying quantities.  Commonly eaten foods such as red peppers, red and green chillies, kiwi fruits and black currants rank at the top of this list, all of which provide at least the double the UK’s recommended intake per 100g. Other foods such as oranges, broccoli, lemons and even white potatoes can provide excellent quantities. A diet rich in fruit and vegetables should be more than adequate to provide enough vitamin C to allow these important processes to function properly.

Vitamin D

Vitamin D plays many roles regulating bone health, hormone production and normal mood. Very foods contain vitamin D which is typically synthesized in the skin after exposure to sunlight. However, in the UK during the winter months even direct exposure to sunlight is not enough to stimulate sufficient vitamin D production and is the reason why vitamin D deficiencies are so common in countries or similar climates. Ensuring enough quantities of oily fish (salmon, mackerels, etc) and eggs, and particularly strong vitamin D supplementation can go a long in bridging this gap and fighting off the effects of being deficient, mostly common the Seasonal Affective Disorder (SAD) found in winter months.

Vitamin E

Vitamin E is a powerful antioxidant that eliminates free radicals and preventing them causing damage to cellular structures. Vitamin E strengthens the immune system and helps to maintain healthy skin and eyes. Vitamin E is primarily sourced from vegetable and nut oils, but also found in high concentration in nuts such as almonds and hazelnuts. Green leafy vegetables such as broccoli, spinach and asparagus are useful sources of vitamin E, but again not for their high concentrations but more due to volume in which these foods are consumed in western diets. Adequate vitamin E should be easy to obtain through a varied and balanced diet, and is readily stored for future use, making vitamin E supplements unnecessary for most people.

Vitamin K

Vitamin K is an essential nutrient in the formation of blood clots and controlling bleeding, aids in wound healing, and aids in controlling the binding of calcium to bones and soft tissues. Vitamin K can be easily obtained in the diet from green leafy vegetables, particularly kale and spinach which are at the top of the rankings, vegetable oils and cereal grains. As with vitamin E, vitamin K is fat soluble which means that your body can store it for use at times where the diet may be lacking, and means that a balanced diet should be sufficient in providing the quantities you need.


Calcium is one of the most important minerals in ensuring the strength and health of bones and teeth, but it also plays important roles in regulating muscle contractions (including the heart), and ensuring that blood clots normally. Calcium is well known to be found in high quantities in dairy products, but for vegans or people with lactose intolerance this can be of no use. Other excellent sources are green leafy vegetables such as broccoli and cabbage, soya, or any bread or cereal products that have been fortified with calcium. Fish, such as sardines and pilchards, where the bones are also consumed can also be good quality sources of calcium.


Iron has one of the most important roles in the body, it plays a key role in red blood cell production which is responsible for the transport of oxygen around our bodies. Like most minerals, animal derived sources of iron are much more bioavailable and valuable to us than those from plant sources, where only a smaller percentage will be utilized by us. Animal meat and liver are two of the most valuable foods in ensuring our iron intake is adequate. However, beans, nuts, wholegrain, fortified cereals and dark green leafy vegetable are also sources of iron, albeit in its weaker non-haem form. Women, in particular need to ensure their iron intake is sufficient, as they lose a significant amount during their monthly cycles.

Omega 3

Omega 3s are essential fatty acids to normal function of the human body. The word essential is used to mean that we cannot synthesis them and so must be obtained in the diet. Omega 3s support the normal metabolism of the human body, as well as helping to combat the onset of cardiovascular disease such heart disease and strokes. The major source of omega 3 fatty acids is from oily fish such as salmon, mackerel or sardines. Some shellfish such as oysters, crab and squid also provide high amounts of omega 3s. Fish oils are frequently used to used as excellent ways of supplementing omega 3s in the diet, with cod liver oil and krill oil being two of the most popular.

Folic Acid

Folic Acid belongs to the group of B vitamins, and it is sometimes known as vitamin B9. Its plays important roles in creating healthy red blood cells, promoting a strong immune system, and aiding in the synthesis and repair of DNA. Folic Acid should be very easy to obtain through diet alone as it found in a wide variety of foods. Avocados, spinach, yeast, liver and asparagus are among the foods with the highest levels of folate, but can also be found in meat, poultry, eggs, dairy, fruit and vegetables, and seafood. Although is a water soluble vitamin folic cannot be stored by the body, and as such must be consumed daily, the vast majority of people should be able to easily meet their daily requirements with a healthy balanced diet. 

Beau Scott

BSc Sports Biomedicine and Nutrition