Metabolism is a global term referring to the sum of chemical reactions that occur withn a living organism, and are broadly divided into two categories: catabolism and anabolism. These are linked to the wide array of activities in the body from growth, aging and the production of energy. Commonly, however, metabolism is used to refer to the level or balance of hormones.Read more
The regulation of aging and energy homeostasis share molecular pathways. Many of the genes recently discovered that can be manipulated to slow the aging process belong to pathways involved in the control of metabolism. Energy homeostasis dysregulation occurs during the aging process, when aged men and women experience a reduced ratio of lean to fat mass, and a redistribution of fat from subcutaneous to visceral areas that surround the internal organs located in the body’s trunk. This leads to decreased insulin sensitivity and increased serum insulin, which can result in the metabolic syndrome and type 2 diabetes. Among younger individuals who have increased visceral fat mass there is a greater risk of the development of diabetes, heart disease, hypertension, gallbladder disease, neurodegenerative disease, and a number of cancers, all of which are associated with aging.
Degree of obesity has also been found to be inversely correlated with life expectancy. Calorie restriction, which has been the most successful means so far to extend the lifespan of numerous species, prevents obesity and has been demonstrated to postpone many signs of aging and protect against a number of age-related diseases. This life extending therapy also has been shown to affect genes involved in energy metabolism. Calorie restriction, as well as genetically manipulating the insulin receptor in fat cells, prevents visceral obesity and its consequent insulin resistance and elevated insulin levels, in addition to extending lifespan.
Our genes interact intimately with our environment. Every bite of food we eat, every thought we think, every stress we experience, and every toxin we ingest or inhale carries a specific message to our genes, turning them on (or off), and telling them how to behave. As a result, our genes are programmed, moment by moment, to actively create either weight loss or weight gain, health or disease.
The selection of food type has greater impact on human metabolism that its simple macro content, the concept that weight is all about caloric management is no longer accepted as the only mechanism that impacts upon body mass, or indeed health. The choice of food micronutrient concentrations, probiotics and gene expression modifiers represent the emerging area of metabolic management via gene expression.
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