The Science Of Aging - Life span in Today 76 (about 60% increase) At this rate life expectancy should be 121 by Future ? Better Nutrition and Medical Advances vs Obesity and Lifestyle issues. Introduction

Why Do We Age? No one scientific reason Some factors are: Hayflick limit - Human cells in vitro have a definite limit to their number of mitotic divisions. Embryonic cells do not seem to be limited Cancer cells do not seem to be limited Why? Both embryonic cells and cancer cells produce telomerase which repairs the telomeres of cells each time they divide. Telomerase is not produced by most normal cells after birth.

Free Radical Production Very reactive molecules containing oxygen are produced as we go through our normal metabolism. Free radicals may damage DNA and proteins Damage starts to occur faster than it can be repaired The cell ages and dies. Accumulated cell damage leads to decreased immune function as well as the signs of aging in the skin and organs. Reason for Aging 2

Reason for Aging 3 Glycosylation - energy reactions in the body cause heated proteins to bond with sugars. Sometimes referred to as “Caramelizing” Ideas on fighting aging 1. Antioxidants - Antioxidant vitamins — E, C and beta carotene (a form of vitamin A) Many antioxidants found in brightly colored fruits and vegetables. 2. Caloric Restriction - Caloric intake restriction has increased the life span of mice up to 3X normal. Reduces the production of free radicals by lowering metabolism Not very practical as it is nearly a starvation diet

Fighting Aging 2 CRON/CRAN - Calorie Restriction Optimum Nutrition Calorie Restriction Adequate Nutrition Being experimented with by many to prolong life. HGH - Human Growth Hormone Restores younger fat distribution Restores muscle mass May increase diabetes and cause heart problems. DHEA - precursor to HGH. Milder effects than HGH. No evidence that it works.

Fighting Aging 3 HRT - Hormone Replacement Therapy Estrogen in women, Testosterone in men May increase the risk or growth of cancer. Telomerase - Activate the gene to make the enzyme to fix the telomeres. Experiments in animal have resulted in increased cancer. Melatonin - Natural chemical that helps you sleep May slow down metabolism Makes you drowsy and may lead to weight gain.