It has been noted that affluent nations are over-fed, as food is affordable and plentiful to the point of intoxication, yet as far as healthy eating is concerned, the general population are somewhat undernourished, as food often lacks essential nutrients, namely antioxidant nutrients. However, this could be overcome through the use of food supplements which encompass vitamins, minerals, essential fatty acids, amino acids, enzymes, herb, fibre, bee products, pro-biotic and phytoeostrogens. Nutritional supplements come in various forms and formulations including tablets, capsules, powder, liquids and herb extracts.Many of us think that we eat a healthy diet that provides plenty of vitamins and minerals, but modern methods of animal farming, food production and cooking methods may significantly influence the nutritive value of food we finally have in the plate. In addition, canning, freezing, chopping, peeling, boiling and the use of food preservatives are known to deplete some essential nutrients. In turns, air pollution from car exhaust and chemical plants as well toxicants in food may put extra demand on nutrient needs especially for micronutrients.There is a question of efficacy, safety and risk of toxicity surrounding the area of dietary supplements. All these factors are related, at least in part, to the supplement source, purity, dosage and the possible interaction between different supplements / ingredients, and / or elements in the diet and most importantly prescribed medication. This is compounded by the availability of enormous range of supplements from various sources.To avoid such drawbacks one should ask the following questions: What supplements to take? Why and what for? Which brand name? How long to take them for? How best to take them? How much and how long a supplement should be taken for? Is there any interaction with any medications currently been taken? And what are the contraindications if any?Self-prescription of nutritional supplements is a common phenomenal of our modern age. Friends or relative recommendations is good enough evidence for the majority of the population for taking a supplement without any attention being given to individual differences, nutritional status, physiological needs or medical history. This is a dangerous practice, despite the fact that most of the dietary supplements available in the market today are controlled by stringent procedures. It is the consumer non-intentional duplication or over dosing, which is a cause of concern, especially if a supplement is taken on large dosages and/or for a prolonged period of time without any input or direction of a healthcare professional.People should be aware of the fact that the need for supplements is usually governed by a multitude of factors; among them are: poor dietary habits, frequent dieting, modern methods of farming & production, reliance on convenience food, level of stress, the degree of environmental pollutants, over-dependence on certain medications e.g. antibiotics and steroids, dietary restrictions brought about by moral and religious beliefs, cultural / ideological factors and the presence of chronic or debilitating diseases. In addition, habitual diet, exercise routine, alcohol over consumption, smoking, social and work environment all have direct or indirect influence on vitamin and mineral requirements. As already stated, preparation and cooking methods, storage, refining / processing, additives, toxicants, pesticides and other chemical are all factors affecting the nutrient values of foods.It is now well known that the main causes of nutritional deficiencies are poor dietary habits, inadequate dietary intakes, mal-absorption, increase losses and/or increase requirement for nutrients. To some extend we no longer suffer from classical symptoms of vitamin deficiencies such as scurvy due to vitamin C deficiency, beriberi brought about by a lack of vitamin B1, pellagra which is caused by lack of vitamin B2, rickets caused by deficiency of vitamin D and Keratomalacia caused by vitamin A deficiency. However, there is a wide spread of mild nutritional deficiencies at blood or tissue level often referred to as sub-clinical nutritional deficiencies. In my opinion these are the major contributory factors to many of the chronic illnesses of today including coronary heart disease, cancer, osteoporosis, and arthritis.The main symptoms of sub-clinical deficiencies may include headache, fatigue, irritability, insomnia, digestive problems and susceptibility to infections. But, some of these are often confused with symptoms of food allergies and intolerances which appears to be quite fashionable nowadays especially among those who consider themselves to be health conscious. The groups most vulnerable to vitamin and mineral deficiencies are pregnant and lactating women, children, adolescents, elderly and dieters due to increased physiological demands as well as those with long term chronic or debilitating illnesses.At present the need for supplements can easily be assessed by a number of techniques including computerised ‘Nutritional analyses. This is based on diet history and a food record diary over several days, typically one week. Blood testing is another technique for assessing the need for individual supplements in a more accurate fashion. Above all what is more important is a prior evaluation by a healthcare professional with specialist knowledge and expertise in the area of nutritional supplements.