Choosing the right supplement to help you get through the next cold, winter months can be mind boggling. Here, femail.co.uk presents an essential guide to the vital supplements your body needs this winter.

We present an A to Z guide to winter vitamins and minerals

Vitamin A: RDA 600-700mcg
This is essential for normal growth, an efficient immune system, healthy skin and good vision. Sources include milk, liver, oil-rich fish, apricots and spinach. Lack of Vitamin A can cause blindness but, in the West, more commonly causes infection and poor growth. However, too much can be toxic. Pregnant women should avoid high concentrations because it has been linked to birth defects.

Vitamin B6: RDA 2mg
One of the eight B complex vitamins, which occur in eggs, wholewheat bread, soya beans and Marmite. Vitamin B6 is needed to release energy from protein and maintain a healthy nervous system. It also helps to produce haemoglobin for the formation of red blood cells. Deficiency can cause anaemia, neuropathy and insomnia. Vitamin B6 has a mild diuretic effect and so can be taken as a way to combat fluid retention.

Vitamin C: RDA 60mg
Also called ascorbic acid, it is vital for growth and essential for the formation of collagen, a protein necessary for healthy bones, teeth, gums, blood capillaries and connective tissues. It also plays an important part in healing wounds and fractures and acts as an antioxidant, helping to protect the heart. Vitamin C, found in many fruit and vegetables, is unstable, and large amounts can be lost through lengthy preparation of food. Signs of deficiency include lethargy, bleeding gums, aching joints and low resistance to infection.

Vitamin D: RDA 60mg
This fat-soluble vitamin is essential for the absorption of calcium and phosphorous. It is vital for the development of healthy teeth and bones, as well as maintaining a healthy nervous system. Found in milk, margarine, egg yolks and oily fish, it can also be synthesised by the body when exposed to sunshine. Ten to 15 minutes of sun three times a week is adequate. Lack of Vitamin D leads to rickets and osteomalacia.

Vitamin E: RDA 10mg
The term Vitamin E applies toeight related compounds known a s tocopherols which functionas antioxidants to protect the bod y from damage from chemicals in the environment by stabilising them before they harm cells. Many studies have suggested that VitaminE can defend against the ill-effects o f smoking, air pollutants and th e sun, as well as preventing cancersand ageing of the skin. It also boosts the immune system. Good sou r ces are almonds, sunflower seeds, hazelnutsand vegetable oils.

Folic Acid: RDA 200mcg-400mcg
A water-soluble vitamin of the B complex group, it is necessary for cell division and the formation of DNA. It is also needed for tissue growth and cell function. Additional folic acid is important to women before conception and during pregnancy because it has been found to prevent birth defects such as spina bifida.Rich sources include dark-green vegetables, liver, wholegrain cereals and yeast extract. Deficiency may lead to poor growth and greying hair.

Glucosamine: RDA 500mg
This is a naturally occurring non-toxic biochemical which can benefit those with osteoarthritis and degenerative joint disease. This is because cartilage, tendons and ligaments rely on glucosamine to continually build their connective tissues. It is formed in the body from glucose and glutamic acid, which can be derived from dietary sources. As well as helping to combat joint problems, it can reduce urinary oxalate levels, so decreasing the chance of kidney stones.

Horse Chestnut: RDA 600mg
The fruit of the horse chestnut tree contains a natural bioflavonoid called aesin which can increase the strength and tone of the veins and encourage healthy blood flow. It achieves this by reducing the permeability of the capillaries. It is a useful treatment for those suffering varicose veins, inflammation of the veins or haemorrhoids. It can also be applied in lotion form on leg ulcers. Taken orally, it helps protect the blood vessels from weakened or impaired function.

Iron: RDA 8-14mg
An essential part of haemoglobin, the pigment in red blood cells that transports oxygen to the body's tissues and organs. Found in lean meat, sardines, fortified breakfast cereals and green, leafy vegetables. It also helps make myoglobin, which stores oxygen in muscle, and boosts the immune system. Lethargy and breathlessness are first signs of iron deficiency, which can lead to anaemia, hair loss, lower resistance to infection and itchy skin. Symptoms include tiredness, pallor and headaches. Vitamin C increases iron absorption.

Juniper: RDA 1-2g capsules three times daily
Supplements containing juniper have been found to be helpful in combating water retentionand urinary tract infections. Its active constituentsare volatile oils which cause an increase in the production of urine.
For this reason juniperis often combined with other diuretic and anti-microbial herbs. However, because of potential damage to the kidneys, juniper should not be taken for more than six weeks continuously .

Vitamin K: RDA 65-70mcg
Essential for producing prothrombin, which causes the blood to clot. Some studies suggest it helps maintain strong bones in the elderly because it is essential for cartilage and bone production.Deficiency leads to a tendency to bleed but this is unlikely because Vitamin K is also synthesised by bacteria that line the gastrointestinal tract in the gut. However, deficiency does occur when there is an inability to absorb it from the intestinal tract. Good food sources include cabbage, cauliflower, soya beans and nuts.

Lycopene: RDA 5mg
Powerful antioxidant cartenoid which gives red foods such as tomatoes their colour. It is central to the Mediterranean diet and is a possible clue to the low incidence of chronic diseases there. Its ability to eradicate cell-damaging free radicals enables lycopene to strengthen the body's natural defences. A 5mg supplement is the equivalent of 100ml tomato paste.

Magnesium: RDA 270-300mg
An essential component of bones and teeth.It also helps to ensure the smooth function of nerves and muscles, including regulating the heartbeat. Deficiency leads to lethargy, fatigue, cramps, muscle tremors and heart-rhythm abnormalities. Good food sources include leafy green vegetables, wholegrain cereals, wheatgerm, pulses and nuts.