Presentation on theme: "EGGS AND CHOLESTEROL by: Ashley Dudley, Tsz Wing Ho and Mjin Song."— Presentation transcript:
EGGS AND CHOLESTEROL by: Ashley Dudley, Tsz Wing Ho and Mjin Song
Outline Misconceptions about eggs and cholesterol Cholesterol – dietary vs blood Cardiovascular disease Diabetes Metabolic Syndrome Dietary Recommendations Health Benefits Weight loss
Common Misconceptions People often believe that… Dietary cholesterol directly affect blood cholesterol Eggs contain high amounts of fat Contributes to atherosclerosis Greater risk of developing cardiovascular diseases Egg consumption should be limited or avoided
Cholesterol: dietary vs blood Dietary cholesterol may not directly affect serum cholesterol 1/3 population is hypersensitive Little effect on LDL:HDL ratio Maintains ratio – key marker of CHD risk Different types of LDL Larger, more buoyant particles less atherogenic Many studies blamed cholesterol for adverse results, but dietary cholesterol intake is often correlated with saturated fat intake; high saturated fat intake is associated with high blood cholesterol and CHD.
Cholesterol Studies 1913 study by Anitschkow and Chalatow showed that feeding high amounts of cholesterol to rabbits induced atherogenesis. Rabbits are highly sensitive to cholesterol Weaknesses of animal studies Blood cholesterol response to dietary cholesterol is highly variable across and within species Most animal species have different lipoprotein profiles compared to humans In nonhuman primates, only extremely high doeses of dietary cholesterol induce hypercholesterolemia and atherosclerosis (1250-5000 mg/2500kcal)
Cardiovascular Diseases Lack of evidence supporting a link between egg consumption and CHD morbidity and mortality. Percentage of saturated and trans fat calories in diet is positively correlated with CHD risk.
Cardiovascular Diseases Fig 1. Relative risk of CHD incidence in males (Health professionals Follow up study) and females (Nurses Health Study) versus weekly egg consumption Fig 2. Relationship between CVD mortality rates in men aged 35-74 among 24 countries and per capita egg consumption
Diabetes Individuals with diabetes face an increased risk of CHD with egg consumption Most studies that show a link to CHD are on diabetic patients Possible relationship of egg consumption and increased risk of type 2 diabetes mellitus. Mechanisms by which high egg and cholesterol consumption influence glucose homeostasis and diabetes risks are largely unknown.
Diabetic Studies Lithuanian study shows that participants who consumed >5 eggs/wk had a threefold increased risk of developing type 2 diabetes than those who consumed <1 egg/wk High egg consumption (>7 eggs/wk) before and during pregnancy were associated with increased risk of developing gestational type 2 diabetes mellitus. Study weaknesses Data was self reported through a questionnaire Did not ask whether participants consumed yolks or whites only
Metabolic Syndrome Metabolic syndrome – a group of risk factors that occur together and increase risk of cardiovascular diseases and diabetes Risk factors: central obesity, high blood pressure, high blood fasting glucose levels, elevated TAG and low HDL Overweight men with MetS on carb restricted diet added eggs to diet for 12 weeks Significant increase in HDL, with no change in LDL 100% of individuals in egg group were no longer classified as having metabolic syndrome.
Metabolic Syndrome Studies Changes in plasma HDL levels from baseline to 12 weeks in overweight men who consume a CRD including 3 eggs/wk or an egg substitute.
Cholesterol Dietary Recommendations AHA recommends no more than 300mg/d for general population in effort to reduce plasma cholesterol levels and CHD risk Those with CHD are recommend no more than 200mg/d Proposed in the 1970s where there was no enough substantial evidence to support this No epidemiological studies support this Extrapolated data derived from early animal studies Other countries do not support an upper limit, due to lack of evidence Focus on limiting intakes of sugar, salt, saturated and trans fats and maintaining a healthy weight Should upper limit be removed? A more reasonable goal of 500mg/d is proposed
Benefits of Eggs Most nutrients in eggs are found in the yolk Complete sources of protein (all 9 essential amino acids) Major source of lutein and zeaxanthin Study in the Journal of Nutrition found that women eating 6 eggs/wk for 12 weeks had increased macular pigmentation, which protects retina Choline Iron Vitamin D B Vitamins (riboflavin, folate) Zinc Lecithin Eggs 1.00 each 50.00 grams 77.50 calories NutrientAmount DV (%) Nutrient Density World's Healthiest Foods Rating choline112.65 mg26.56.2very good tryptophan0.08 g25.05.8very good selenium15.40 mcg22.05.1very good iodine27.00 mcg18.04.2very good vitamin B20.26 mg15.33.6very good protein6.29 g12.62.9good molybdenum8.50 mcg11.32.6good vitamin B120.55 mcg9.22.1good phosphorus86.00 mg8.62.0good vitamin B50.70 mg7.01.6good vitamin D26.50 IU6.61.5good World's Healthi est Foods RatingRul excelle nt DV>= 75% OR Densit y>=7. 6 AND DV>= 10% very good DV>= 50% OR Densit y>=3. 4 AND DV>= 5% good DV>= 25% OR Densit y>=1. 5 AND DV>= 2.5%
Weight Loss Average egg contains 210 mg of cholesterol 1.5 g saturated fat 6 g protein 70 calories Eggs promote satiety, casing lower caloric intake throughout the day 2 eggs for breakfast may aid in weight loss Cheap and convenient
Weight Loss In comparison to a bagel based breakfast, an egg based breakfast helped participants lose weight. After 8 weeks, the egg based breakfast showed: 61% greater reduction in BMI 65% greater weight loss 34% greater reduction in waist circumference 16% greater reduction in body fat percentage
Conclusion Most misconceptions regarding eggs arent true. Dietary cholesterol does not directly affect blood cholesterol levels. Eggs do not increase the risk of CHD in the general population. Those with diabetes should be cautious of egg consumption, though further research is needed. Upper limit needs to be rethought. Eggs are nutrient dense and offer many benefits.
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