Vitamins and minerals are organic compounds that our bodies use in very small amounts for a variety of metabolic processes. Basically, they keep us healthy and help our bodies to function. Show
We get vitamins and minerals from the foods we eat. For most of us, a healthy and varied diet (that includes all 5 food groups) is all we need to stay healthy. It is best to get vitamins and minerals from eating a variety of healthy unrefined foods. Vitamins and minerals can cause toxicity if consumed in large amounts. Types of vitamins and their functionsVitamins and minerals are a form of nutrient (called micronutrients) that are needed in small amounts. Although micronutrients don’t give us energy, they are involved in the metabolic processes that enable us to get energy from carbohydrates, protein and fat, which are also known as macronutrients. Different vitamins serve different purposes and contribute to different bodily functions. There are 13 vitamins in total and 8 of these come from the B-group of vitamins. Vitamin AVitamin A is important because it: Food sources of vitamin AThere are different compounds with vitamin A activity in animal and plant foods. Plant foods can be easy to spot as they tend to have orange/yellow pigment known as beta-carotene. Plant sources include:
Animal sources include:
Vitamin A deficiency risksBecause of the various roles that vitamin A plays in the body, deficiency can have several health effects. These include:
Vitamin BB-group vitamins help our bodies use the energy-yielding nutrients (such as carbohydrates, fat and protein) for fuel. Some B-group vitamins are needed to help cells to multiply by making new DNA. Except for B-12 and folate which are stored by the liver, most B-group vitamins can’t be stored by the body. They must be consumed regularly in a healthy diet that includes a range of wholefoods (such as lean meat, fish, wholegrains, fruit, vegetables and legumes) and limits the intake of alcohol and processed foods. The 8 types of vitamin B are:
A person who has a poor diet for a few months may end up with B-group vitamins deficiency. For this reason, it’s important that adequate amounts of these vitamins be eaten regularly as part of a well-balanced, nutritious diet. Vitamin CDietary intake of vitamin C (from food and drinks) is essential, because the human body cannot make this vitamin from other compounds. We also need to have vitamin C as a regular part of our diet because the body cannot store vitamin C for very long. Vitamin C (ascorbic acid) is important for many metabolic processes, including:
Dietary sources of vitamin CAdults need about 45mg of vitamin C per day and any excess amount (above 200mg) is excreted. Vitamin C is sensitive to heat, so some of its nutritional benefits can be lost during cooking. Raw foods are more beneficial as dietary sources of vitamin C. These include:
Vitamin C deficiency and scurvyA severe lack of vitamin C can lead to scurvy. We may think of it as a disease of the past, but it does still exist. Factors or lifestyle issues that may increase your scurvy risk include:
Scurvy symptomsThe onset of symptoms of scurvy depends on how long it takes for the person to use up their limited stores of vitamin C. Scurvy is usually easy to treat – symptoms are like many other mild complaints and may include:
If you or someone you care for is at risk, please see your doctor. Vitamin DVitamin D is important for strong bones, muscles and overall health. Ultraviolet (UV) radiation from the sun is necessary to produce vitamin D in the skin and is the best natural source of vitamin D. Regular physical activity also assists with the body’s production of vitamin D. The body can only absorb small amounts of Vitamin D. Spending too much time in the sun may increase your risk of skin cancer. Remember to use daily sun protection, especially at times when UV index levels are at their highest (3 or above). Food sources of vitamin DOnly a small amount (around 5-10%) of Vitamin D is sourced from our diet. Sources include:
Vitamin D deficiencyIt is important to achieve a good peak bone mass early in life. Vitamin D deficiency can result in a decline in bone density in adult life, increasing the risk of: Treatment options include improved sunlight exposure, diet, exercise, vitamin and mineral supplements. If you are concerned about vitamin D levels, see your GP. Your GP may recommend vitamin D supplements, which should be taken strictly as directed. Vitamin EVitamin E is an antioxidant that helps protect your body against damage from free radicals, such as exposure to cigarette smoke or radiation. It is also important for our:
Dietary sources of vitamin EVitamin E is best obtained from a healthy diet that contains plenty of fresh minimally processed foods. Vitamin E is also vulnerable to heat (especially cooking methods such as deep frying. Dietary sources include: Vitamin E deficiencyDeficiency is rare but can happen in people with diseases that cause fat malabsorption (like cystic fibrosis). Erythrocyte haemolysis is another deficiency – it’s seen in infants born before vitamin E is transferred to them from their mother prior to birth. Vitamin KVitamin K is important for:
Dietary sources of vitamin KWe get vitamin K from food and the bacteria in our gastrointestinal tract. Newborn babies are given a booster to increase their vitamin K levels because they are born without bacteria in their gastrointestinal tract. We get much of our vitamin K from our diet. Food sources include:
Vitamin K deficiencyVitamin K deficiency is unlikely except when fat is not absorbed properly or when certain medications are used. For example, antibiotics can kill the gastrointestinal bacteria that produce vitamin K. Additionally, anticoagulant drugs (or blood thinners) may cause problems with vitamin K in the body. Check with your doctor if you have any concerns. Types of minerals and their functionsThere are hundreds of minerals – they are usually classified as either major or trace minerals. Although the amount you need differs between minerals, major (or macrominerals) are generally required in larger amounts. Some examples include calcium, phosphorus, potassium, sulphur, sodium, chloride, magnesium. Trace minerals (microminerals), although equally important to bodily functions are required in smaller amounts. Examples include iron, zinc, copper, manganese, and iodine selenium. Some of the important minerals to keep us healthy are listed below. CalciumCalcium is vital to keep our bones strong and healthy. If you don’t get enough calcium, your bones will eventually become weak and brittle and can lead to conditions like osteoporosis. Calcium helps:
Food sources of calciumAt different life stages, our calcium needs vary. It is better to get calcium from foods than from calcium supplements. Good sources of calcium include dairy foods like milk, yoghurt and cheese and some plant-based foods with added calcium (for example, soymilk, tofu and breakfast cereals). Other sources of calcium include almonds, bok choy, kale, parsley, broccoli and watercress. IodineIodine is essential to make thyroid hormones. These hormones control your metabolic rate (the rate your body uses energy when it is resting). They also help your brain and body grow and develop. Food sources of iodineWe only need a very small amount of iodine in our diet. Iodine is found naturally in foods such as:
Iodine can also be found in iodised salt. All bought breads (except organic) in Australia are fortified with iodised salt. You are likely to be getting enough iodine through your diet. However, if you are deficient and need to take a supplement, be guided by your doctor. Too much iodine can be harmful, especially if you have an underlying thyroid disorder. IronIron is an important mineral that is involved in various bodily functions, including the transport of oxygen in the blood the provision of energy to cells. It also vital to help our immune system function effectively to fight infection. Food sources of ironIron can be found in animal and plant foods including:
Iron deficiencyIron deficiency is common and can affect adults and children. Around one in 8 people do not consume enough iron to meet their needs. Some factors such as certain foods and drinks can affect how much iron your body absorbs. Also, some groups are more at risk of iron deficiency, such as babies and young children, teenage girls, women with heavy periods, vegans and vegetarians and people with chronic conditions. ZincZinc is an important mineral involved in various bodily functions – growth and development as well as immune function. Zinc also helps to produce the active form of vitamin A and transports it around the body. Food sources of zincZinc is highest in protein-rich foods but may also be found in some plant foods. Dietary sources include:
MagnesiumMagnesium is important due to its many functions in the body – including maintaining bone health and using glucose for energy. Magnesium also supports immune function and helps regulate blood pressure and lung function. Food sources of magnesiumDietary sources include:
PotassiumPotassium is important for the nerves, muscles and heart to work properly. It also helps lower blood pressure. Food sources of potassiumOur bodies are designed for a high-potassium diet, not a high-salt diet. Food processing tends to lower the potassium levels in many foods while increasing the sodium content. It is much better to eat unprocessed foods – such as fruit, vegetables and lean meats, eggs, fish and other healthy, everyday foods. Foods high in potassium include:
Be guided by your doctor, some people with kidney disease, or who are taking some medications, need to be careful not to get too much potassium in their diet. SodiumA small amount of sodium is important for good health as it helps to maintain the correct volume of circulating blood and tissue fluids in the body. Most of us are consuming far more sodium than we need. In fact, many Australians are consuming almost double the amount required. Too much sodium can lead to high blood pressure (hypertension) and other health conditions. Food sources of sodiumSalt is the main source of sodium in our diet. It is a chemical compound (electrolyte) made up of sodium and chloride. Many foods – wholegrains, meat and dairy products – naturally contain small amounts of sodium, while highly processed foods usually contain large amounts. Vitamin and mineral deficiencies and supplementsThe fat-soluble vitamins A, D, E and K can be locked away in the liver and body fat, and stored for a long time. The water-soluble vitamins, including B-complex and vitamin C, are mostly only stored for a shorter period. A vitamin deficiency takes weeks or months before it will affect your health. For instance, it would take months of no vitamin C before you developed scurvy. |