Food is the basic necessity of life of human being. Foods can be found everywhere with a variety of tastes, textures, colors and physical appearances. Vitamins are negligible components of foods that play an important role in human nutrition. Fat-soluble vitamin is one of the types of vitamins found in foods. “Fat-soluble vitamins are defined as “vitamins from different food groups related to their fat solubility” (deMan, 1999, p. 355). In general, fat-soluble vitamins can be classified into four broad categories: vitamin A, vitamin D, vitamin E and vitamin K (see Figure 1 in Appendix 1). The first type of fat-soluble vitamin is vitamin A. Vitamin A is a group of unsaturated nutritional organic compounds that includes retinol, retinol, retinoic acid, and several provitamin A carotenoids. According to Hickenbottom, Lemke and Clifford (2002), vitamin A is derived from beta-carotene which serves as an antioxidant and may help protect against certain cancers and heart diseases. Rhodopsin is the photosensitive pigment present in these nerve cells and synthesized by vitamin A (Minke & Kirschfeld, 1979). Additionally, vitamin A contributes to the formation of mucopolysaccharide sulfates which are used for cell adhesion, regulation of cell growth and developmental processes (Wolf & Varandani, 1960). Earl (1933) mentioned that vitamin A is one of the vitamins that contribute to growth, repair of body tissues, bone formation, and the formation of healthy skin and hair. For more information, vitamin A also participates in the synthesis of sex steroids essential for skeletal development and the maintenance of bone health throughout adult life (Compston,‎ 2001). Vitamin A also plays a role in the cell membrane. There is...... in the middle of the article ......thesis a family of compounds called menaquinones (vitamin K_2). People who do not consume it regularly are likely to have insufficient intake of vitamin K. Well, this can be avoided by adopting a proper diet. Some people can be lenient about this and don't care much about their healthy lifestyle, which can lead to serious blood clotting problems. Additionally, low levels of vitamin K may increase the risk of uncontrolled bleeding and a healthcare professional might suggest that patients take vitamin K supplements (Tremblay, n.d.). Therefore, vitamin K is very important in helping clotting to prevent excessive bleeding. In conclusion, there are four main types of fat-soluble vitamins and they are differentiated by their biological role, food sources and deficiency diseases. These are essential components of the diet that are important for our health..