Photodamage is known to occur in skin with exposure to sunlight, specifically ultraviolet (UV) radiation. Such damage includes inflammation, oxidative stress, breakdown of the extracellular matrix, and development of cancer in the skin. Sun exposure is considered to be one of the most important risk factors for both nonmelanoma and melanoma skin cancers. Many phytonutrients have shown promise as photoprotectants in clinical, animal and cell culture studies. In part, the actions of these phytonutrients are thought to be through their actions as antioxidants. In regard to skin health, phytonutrients of interest include vitamin E, certain flavonoids, and the carotenoids, ß-carotene, lycopene and lutein.
Continue Reading » The Role of Phytonutrients Like Vitamin E and Beta-Carotene in Skin Health
Vitamin E, like tocotrienols and tocopherols, is constituted of compounds essential for animal cells. Vitamin E is exclusively synthesized by photosynthetic eukaryotes and other oxygenic photosynthetic organisms such as cyanobacteria. In order to prevent lipid oxidation, the plants mainly accumulate tocochromanols in oily seeds and fruits or in young tissues undergoing active cell divisions. From a health point of view, at the moment there is a great interest in the natural forms of tocochromanols, because they are considered promising compounds able to maintain a healthy cardiovascular system and satisfactory blood cholesterol levels. Some evidence suggests that the potency of the antioxidant effects may differ between natural or synthetic source of tocochromanols (vitamin E).
Continue Reading » Vitamin E Update: Tocopherol and Tocotrienol
Vitamin E and C for Strength and Bodybuilding: Should You Take Them for Exercise Induced Oxidative Stress?
Oxidative stress is an imbalance between free radicals (pro-oxidant molecules) and the body's oxidative defense mechanisms. Primarily the free radicals in our bodies are derived from the consumption of oxygen but there are many possible radical species. The basic definition is a particle that contains one or more unpaired electrons and this can be true of many different substances. However the most important ones for us are those derived from oxygen or nitrogen. They are called reactive oxygen/nitrogen species or RONS for short.
The topic of exercise-induced oxidative stress has received considerable attention in recent years, with close to 300 original investigations published since the early work of Dillard and colleagues in 1978. Single bouts of aerobic and anaerobic exercise can induce an acute state of oxidative stress. This is indicated by an increased presence of oxidized molecules in a variety of tissues. Exercise mode, intensity, and duration, as well as the subject population tested, all can impact the extent of oxidation. Moreover, the use of antioxidant supplements can impact the findings. Although a single bout of exercise often leads to an acute oxidative stress, in accordance with the principle of hormesis, such an increase appears necessary to allow for an up-regulation in endogenous antioxidant defenses. This review presents a comprehensive summary of original investigations focused on exercise-induced oxidative stress. This should provide the reader with a well-documented account of the research done within this area of science over the past 30 years.
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Sports success is dependent primarily on genetic endowment in athletes with morphologic, psychologic, physiologic and metabolic traits specific to performance characteristics vital to their sport. Such genetically-endowed athletes must also receive optimal training to increase physical power, enhance mental strength, and provide a mechanical advantage. However, athletes often attempt to go beyond training and use substances and techniques, often referred to as ergogenics1, in attempts to gain a competitive advantage. Pharmacological agents, such as anabolic steroids and amphetamines, have been used in the past, but such practices by athletes have led to the establishment of anti-doping legislation and effective testing protocols to help deter their use. Thus, many athletes have turned to various dietary strategies, including the use of various dietary supplements (sports supplements), which they presume to be effective, safe and legal.
Continue Reading » Vitamins and Sports Performance