Fat cells and fat droplets are not mere passive receptacles of calorie bearing molecules.  They are also active metabolic entities capable of receiving signals. Signals to fat cells may signal them not to store any additional fat, and also to break down the fat already in the cells.  Oleic acid was one fatty acid that appeared to be effective for this signal (1), and olive oil is 85% oleic acid.  A weight loss study used oleic acid in combination with DHA and branched-chain amino acids as a nutraceutical supplement to induce weight loss in humans (2). 
 (1) 	 Reduced Fat Mass in Rats Fed a High Oleic Acid–Rich Safflower Oil Diet Is Associated with Changes in Expression of Hepatic PPARα and Adipose SREBP-1c–Regulated Genes J. Nutr. 136: 1779-1785 (2006)   
 (2) 	 Pilot study for an age- and gender-based nutrient signaling system for weight control,  AGE 30: 201-208 (2008)  

  

 Although epidemiologic evidence and animal studies suggest that olive oil may prevent the onset of cancer, the components responsible for such an effect and their mechanisms of action remain largely unknown... These results support the hypothesis that polyphenols play a critical role in the anticancer activity of olive oil.(Roc’s nutrition page). 
 Skin Care 
 Olive oil has been known for generations not only for its healing qualities but also as a natural, deep penetration moisturizer, regenerating skin cells and softening the tissue.  
 It acts as a natural preservative and antioxidant for the other ingredients in the beauty products, and directly acts as an antioxidant for the skin, protecting it against free radical damage.  

  
 Protection ( at the end of Production): 
 In particular, it is necessary to protect the oil against lipid oxidation which can have many deleterious effects on the quality of virgin olive oil, including the formation of unpleasant organoleptic characteristics, the drastic reduction of the bouquet and taste notes as well as the reduction of naturally-occurring antioxidant compounds and therefore shortening of its the shelf life.  
 Production: 
 The different names for olive oil indicate the degree of processing the oil has undergone as well as the quality of the oil. Extra-virgin olive oil is the highest grade available, followed by virgin olive oil. The word "virgin" indicates that the olives have been pressed to extract the oil; no heat or chemicals have been used during the extraction process, and the oil is pure and unrefined. Virgin olive oils are the healthiest, since they contain the highest levels of polyphenols, antioxidants that have been linked with better health.  

 Nutrition & Current Researches: 
 The US Food and Drug Administration permitted a claim on olive oil labels stating: "Limited and not conclusive scientific evidence suggests that eating about two tablespoons (23g) of olive oil daily may reduce the risk of coronary heart disease."  

 Olive oil protects against heart disease as it controls the "bad" levels of LDL cholesterol and raises levels of the "good" cholesterol, HDL.  
 Olive oil is also rich in polyphenols, which have anti-inflammatory, antioxidant and anticoagulant actions, which may be another reason why it is important for heart health.  
 The cons Olive oil is light sensitive and must be stored in opaque containers away from heat sources to maintain its quality.  
 Olive oil, like all fats, is high in kilojoules, so should be consumed in moderation. But if you replace the saturated or trans-fats in your diet with olive oil, your kilojoule consumption will remain the same and you will be gaining health benefits.  
 The rats fed with olive oil saw their tumours grow far more slowly than those fed the vegetable oil or the normal diet. The amino acids in the olive oil may help to block a key gene that fuels the growth of cancer cells.  

 pH 
 pH refers to the hydrogen ion concentration in an aqueous solution. Olive oil and other oils are not water soluble so their acidity cannot be measured in terms of pH.  
 Vitamin E (a natural antioxidant): Olives have 1.6mg, or 2.3 IU (International Units) per tablespoon. One tablespoon provides 8% of RDA for vitamin E. 
 Vitamin K: The richest sources of vitamin K are green, leafy vegetables. One serving of spinach or collards, for instance, or two servings of broccoli provide four to five times the RDA. The greener the vegetable, the higher the content, say the researchers, because the vitamin is associated with the chlorophyll. According to the USDA , vegetable oils such as olive oil are the second best source.