Lipids PBHL 211 Darine Hachem, MS, LD
Outline Functions of lipids in our body Types of lipids Sources of lipids Recommendation of fat intake Fat association with heart diseases
Provide energy (9Kcal/g fat) Role of fat in our body Stored in adipose tissues No limit for fat storage Fat cells expand in size, and then new adipose cells are formed to store further fat Acts as an Insulator Protects the body from shocks Part of cell membranes Slow digestion and provides satiety Transports fat-soluble vitamins (A, D, E, K)
High Fat Food Sources
Healthy Fats??
What are the different types of fats that we consume?
1. Saturated fatty acids 2. Unsaturated fatty acids omufa opufa 3. Trans fatty acids 4. Cholesterol
Saturated Fatty Acids Monounsaturated Fatty Acids (MUFA) Unsaturated Fatty Acids Polyunsaturated Fatty Acids (PUFA: ω-3 and ω-6) Structure No double bond One double bond Two or more double bonds Source Mainly Animal sources Tropical Oils Plants Nuts Plants Nuts Seafood Food Sources Structure at Room Temperature Butter, dairy products, meat, chicken Coconut oil and Palm oil Solid at room temperature Olive oil Avocado Sesame Peanut Canola oil Liquid at room temperature Walnuts Salmon Flaxseeds Liquid at roomtemperature Stability Stable Not very stable Not very stable
Health benefits of MUFA Monounsaturated fats help in improving blood cholesterol levels Can decrease heart disease risk http://www.eatright.org/resource/food/nutrition/dietary-guidelines-and-myplate/choose-healthy-fats
Essential fatty acids: Not synthesized in the body Structural part of cell membranes Major part of lipids in brains and nervous system Essential for normal growth in infants and children Transformed into hormone-like substances: (blood clot formation, blood pressure, immune inflammation responses )
Lower blood cholesterol Health benefits of ω- 3 fatty acids Lower triglycerides Decrease risk of blood clot formation Reduce blood pressure Improve blood vessel function and delay the build up of plaque in coronary arteries Decreasing the risk for heart attacks & stroke https://www.heartfoundation.org.au
Where do we get our ω-3 sources from?
Sources of (ω- 3) fatty acids: 1. Seafood 2. Plant sources Seafood (Fatty fish) Salmon Tuna Sardines Plants: Walnuts Flaxseeds Chia seeds Canola oil Soybean oil
Oil and Shelf life
Unsaturated fatty acids: Have a short shelf life Become rancid (double bonds in MUFAs and PUFAs react with atmospheric oxygen) HOWEVER! How can unsaturated fatty acids become more stable for use in the food industry?
Hydrogenation
Chemical process by which hydrogen atoms are added to unsaturated fatty acids (liquid oils) Hydrogenation: Upon Hydrogenation fats become: more saturated more solid (semi-solid structure) more stable- has a longer shelf life
HOWEVER!! Hydrogenation A new type of unsaturated fatty acids are produced: TRANS FATTY ACIDS Increase the risk for heart diseases by: LDL and HDL cholesterol in blood
High Trans Fat Food Choices High Trans Fat Food Choices
The process of hydrogenation used by the food industry: Sources of Trans Fats o Cakes, cookies, pie crusts and crackers made from partially hydrogenated vegetable oil o Chips o Packaged or microwave popcorn o Fried food: French fries, doughnuts and fried chicken (deep frying) Can contain trans fat from the oil used in the cooking process o Creamer and margarine
Cholesterol Not an essential fat: Synthesized in the liver of humans Liver produces ~ 800 to 1500 mg cholesterol/day Total blood cholesterol should be less than 200 mg/dl
Which foods are rich in cholesterol? Cholesterol is found in animal products only Cholesterol-rich foods: Eggs Shellfish Red meats, liver Dairy products
LDL v/s HDL Cholesterol
LDL- Cholesterol: Transports cholesterol from the liver to tissues Bad cholesterol Associated with heart disease V/S HDL- Cholesterol: Transports cholesterol from tissues back to the liver Good cholesterol Protective role
Factors that Increase HDL-cholesterol Exercise Estrogen (women) Weight loss (if obese) HDL goal >60 mg/dl Factors that Increase LDL-cholesterol Saturated fat intake Trans fat intake Smoking Obesity Sedentary lifestyle LDL goal< 80 mg/dl
Fats and Cardiovascular Diseases
CVDs are the number 1 cause of death globally Prevalence of CVDs Globally http://www.who.int/mediacentre/factsheets/fs317/en/
Over 75% of CVD deaths occur in: low- and middle-income countries
How can we prevent heart diseases?
Most cardiovascular diseases can be prevented by addressing behavioral risk factors: 1. Tobacco use 2. Unhealthy diet and obesity 3. Physical inactivity (sedentary lifestyle) 4. Harmful use of alcohol Using population-wide strategies http://www.who.int/mediacentre/factsheets/fs317/en/
Individual-Level Management
Risk Factors for CVDs 1. High Blood Cholesterol Levels 2. Smoking 3. Hypertension (high blood pressure) Other Risk Factors include: Obesity Physical Inactivity Diabetes
ATHEROSCLEROSIS Atherosclerosis (cont d)
Narrowing/ Hardening of arteries (Atherosclerosis) Blood Flow Blocked Heart Attack Stroke
Dietary Recommendations
Dietary Recommendations Excess fat consumption can lead to: Obesity, CVD, and some types of cancer Total fat intake: 30% of Total daily calories 10% of each of SFA, MUFA and PUFA Dietary cholesterol: ~ 300 mg/day from the diet Trans fat: should be limited
AVOID: Frying your food Even healthy oils can become unhealthy upon heating Prolonged consumption of burnt oils can lead to atherosclerosis Dietary Recommendations Eating processed/ packaged food High in sodium, saturated fat, sugars, and trans fats CHOOSE: Healthy alternatives to frying: Baking Broiling Grilling Using oil sprays Eat fish twice a week
Lifestyle Changes: 1. Follow a healthy diet 2. Maintain a healthy weight 3. Perform regular physical Heart Health & Diet activity 4. Quit smoking 5. Manage stress http://www.eatright.org/resource/health/wellness/heart-and-cardiovascular-health/heart-health-and-diet
A Heart-Healthy Diet: 1. Follow a healthy eating pattern across the lifespan 2. Focus on variety and nutrient density 3. Control your meal and snack portion sizes 4. Limit calories from added sugar and saturated fat 5. Reduce sodium intake 6. Choose healthier food and beverages 7. Support healthy eating patterns for all X (With reference to the 2015 Dietary Guidelines for Americans) http://www.eatright.org/resource/health/wellness/heart-and-cardiovascular-health/heart-health-and-diet
THANK YOU