Ancel Keys – found that percent of calories from fat and level of cholesterol in the blood were associated with the rate of heart disease o Keys found that in Crete, Greece, they had a diet high in fat (about 30%, mostly of the vegetable type) and a low incidence of heart disease Mediterranean diet that Keys recommended Atherosclerosis – a problem in newer public health Maasai – has a diet extremely high in fat (eat a lot of meat and drink a lot of milk) and have a low incidence of heart disease o Also Inuit, Rendille, Tokelau Australian Aborigines – high rate of heart disease in spite of the fact that they have low cholesterol and low animal fat intake o When you look at their blood cholesterol, low in HDL and their LDL is of the “small particle” type When Keys figured out his curves, there was data for 22 countries and he only used 6 John Yudkin – is it only percent calories from fat that heart disease relates to? o What about sugar intake? Also paralleled increase in heart disease Keys was aware of sugar connection – explained that heart disease correlates with sucrose in the diet because of the intercorrelation of sucrose with saturated fat St. Helena – high heart disease rate with diet low in fat but high in sugar Questioned heart attack patients and found that they had been eating twice as much sugar as controls Intervention study – put young men on sugar-rich diet and a third showed “sugar sensitivity” with increase in insulin, cortisol, weight, and platelet aggregation Coronary heart disease is the leading cause of death o Build-up of plaque in coronary arteries (feed the heart) Sometimes a blood clot can form around the site of the plaque and chokes of the flow of blood, causing a heart attack Video 3 Risk factors for heart disease: o Low birth weight o Born male o Hypertension – high blood pressure (constant pressure beating against walls of arteries damages them and plaque builds up) o Inactivity o Obesity
o Smoking o Diabetes o Stress o Microbes – some bacteria can afect the heart and predispose it to heart disease Some of the bacteria comes through the mouth – must keep gums healthy o High triglycerides – “fat in the blood” 3 fatty acids are linked to glycerol o Homocysteine Homocysteine – formed in the body from methionine (amino acid that’s a component of all proteins and when we eat it, it’s metabolized) and it eventually breaks down (catalyzed by B vitamins) into various metabolites o Dr. McCully injected homocysteine into rabbits and it triggered heart disease Harvard study (1992) – 14,000 male physicians studied o Those whose blood levels of homocysteine were in the top 5% had a heart attack risk three times greater than in subjects with the lowest levels o Recommended values of homocysteine intake: Men – 8-12 Micromol/L Women – 6-10 Micromol/L Risk begins – 11 Micromol/L How do you reduce homocysteine?
- Spring '11
- Nutrition, Atherosclerosis, Causes of cancer