Adipose Tissue Function in the Body

Why Is It Important? Energy stores in the form of fat – main role of AT While carbohydrates are main source of energy in body, fat provides the most energy per gram (9kcal) Protection – cushion for body/internal organs, muscle fibers, nerves (myelin sheath), blood vessels Temperature regulation – insulation (reduced heat loss through skin) Cell membrane structure, vitamin (A,D,E,K) storage and transport, reproductive function, secretion of chemicals controlling appetite

Good Fats vs. Bad Fats “Good” fats – reduce risk of heart disease Monounsaturated: vegetable oils, nuts, avocado,… Polyunsaturated: omega-3 & omega-6 fatty acids, soybean oil, fish, flaxseed,… “Bad” fats – heart disease (atherosclerosis) Saturated: butter, margarine Trans: processed, fried, frozen foods

Atherosclerosis

Cholesterol and its Role in the Body Cholesterol: lipid produced by liver, consumed in diet Vital for body function! Carried in blood by lipoproteins LDL (“bad” cholesterol): liver  cells – increased risk of CVD/CHD Increased by consumption of saturated fats and trans fatty acids HDL (“good” cholesterol): cells  liver – decreased risk of disease Increased by regular physical activity/exercise Decreased by consumption of trans fatty acids

Age and Maturation With age…  brown AT  overall AT Puberty – hyperplastic growth Pregnancy – hyperplastic growth Slowed metabolism – hypertrophic growth Changes in AT distribution Menopausal women -  subcutaneous abdominal fat

Gains per Year Analysis of weight and eating and lifestyle habits of nearly 121,000 men and women – tracked every 4 years over a 20 year time period Average +3.35lbs/4 years, +17lbs/2 decades Most unhealthful dietary changes: +4lbs/4 years Extra serving of chips per day: +1.7lbs/4 years One more sugar-sweetened beverage a day: +1lb/4 years Other factors: decreased physical activity, increased alcohol intake, less than six hours of sleep a night or more than eight, increased screen time