1. Adipose Tissue EDDIE SMITHLEAH WAGNER LEAH SANDERSJONATHAN GRIMWOOD FWS

2. What is adipose tissue?  Groups of adipocytes (lipid filled cells) that are loosely held together by collagen fibers and connective tissue cells.  Functions  Source of energy  Heat insulation  Mechanical cushioning

3. What is adipose tissue?  Formed from pre-adipocytes  Fat cells that have not yet been filled with lipids  Already present in adipose tissues  Can grow through adult life  One capillary per adipocyte for improved metabolism  Fat is primarily an energy source  Storing energy as another source would be inefficient and limit mobility  “Buffer” when energy expenditure is greater than energy intake http://www.promocell.com/products/human-primary-cells/preadipocytes/

4. Composition of Adipose Tissue  Two Types  White fat cells – most common form; used for energy, insulation, and cushioning  Brown fat cells – metabolically less active; primary function is to generate body heat; can be activated with cold exposure  Unilocular vs. multilocular  Uni – single, larger lipid droplet   Multi – many smaller droplets www.sportsci.org

5. Composition of Adipose Tissue  60-85%  Lipids  90-99%  Triglycerides  Fatty Acids: myristic, palmitic, palmitoleic, stearic, oleic, linoleic  Others: FFA, diglycerides, cholesterol, phospholipids, cholesterol ester, monoglycerides (change based on diet)  5-30%  Water  2-3%  Protein http://www.sportsci.org/encyc/adipose/adipose.html#distrib

6. How much resides in average adult?  Normal weight adults can have between 15-30% of adipose tissue  Current average is 28-40% body fat, due to recent obesity epidemic.  Even those with normal BMI had high fat %  Lower BMI/weighing less does not always mean healthier http://onlinelibrary.wiley.com/doi/10.1038/oby.2010.103/epdf Mean Percentage Body Fat, by Age Group and Sex --- National Health and Nutrition Examination Survey (NHANES), United States, 1999--2004

7. How much resides in average adult? Mean Percentage Body Fat, by Age Group and Sex --- National Health and Nutrition Examination Survey (NHANES), United States, 1999--2004 Ranges Based on Age  Male  16-19 yo average - 22.9%  60-79 yo average - 30.9%  Female  8-11 yo average - 32.0%  60-79 yo average - 42.4%

8. How average percentages differ? American Council on Exercise

9. How much resides in average adult?  Essential levels of fat are necessary for insulation, protection, and energy purposes  Body uses fat for energy when at rest  Lack of sufficient fat stores will prevent the body from efficiently providing energy to the cells

10. Where can adipose tissue be found?  Subcutaneous – directly under the deepest layer of skin; insulation  Visceral – near organs; directly related to CVD & Hypertension www.westlakedermatology.com

11. Distribution  Men – Android/”Apple”  Upper body  Waist  Abdomen  Women – Gynoid/”Pear”  Lower body  Hips  Thighs  Buttocks Note: Android/”Apple” storage sites are considered to be more dangerous to health because of fat location in relation to important organs. www.sportsci.org

12. Determining factors of distribution  Genetics  Family history is a great predictor of fat distribution patterns  Gender  Male – Upper body (“Apple”)  Female – Lower body (“Pear”)  Age  An increase in upper body/visceral fat has been observed in older women.  “Yo-yo dieting”  May increase upper body fat distribution http://www.sportsci.org/encyc/adipose/adipose.html Am J Clin Nutr. 1997 Jul;66(1):111-5