EGGS AND CHOLESTEROL by: Ashley Dudley, Tsz Wing Ho and Mjin Song.

EGGS AND CHOLESTEROLby: 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 cholesterolEggs contain high amounts of fatContributes to atherosclerosisGreater risk of developing cardiovascular diseasesEgg 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 1970’s 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

Cholesterol Dietary Recommendations

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

Eggs1.00 each50.00 grams77.50 calories

Nutrient AmountDV(%)

NutrientDensity

World's HealthiestFoods Rating

choline 112.65 mg 26.5 6.2 very good

tryptophan 0.08 g 25.0 5.8 very good

selenium 15.40 mcg 22.0 5.1 very good

iodine 27.00 mcg 18.0 4.2 very good

vitamin B2 0.26 mg 15.3 3.6 very good

protein 6.29 g 12.6 2.9 good

molybdenum 8.50 mcg 11.3 2.6 good

vitamin B12 0.55 mcg 9.2 2.1 good

phosphorus 86.00 mg 8.6 2.0 good

vitamin B5 0.70 mg 7.0 1.6 good

vitamin D 26.50 IU 6.6 1.5 good

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 aren’t 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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