Answer to Question 1
Many observational studies suggest that elevated levels of the amino acid homocysteine may be an independent risk factor for heart disease, heart attacks, and sudden death in patients with heart disease; findings from prospective studies, however, are far less conclusive. Researchers do not yet fully understand the many factorsincluding a diet high in saturated fatty acidsthat can raise homocysteine in the blood or whether elevated levels are a cause or an effect of heart disease. Elevated homocysteine is associated with increased oxidative stress and inflammation. Until researchers can determine the exact role homocysteine plays in heart disease, they are following several leads in pursuit of the answers. Coffee's role in heart disease has been controversial, but research suggests it is among the most influential factors in raising homocysteine, which may explain some of the adverse health effects of heavy consumption. Elevated homocysteine levels are among the many adverse health consequences of smoking cigarettes and drinking alcohol as well. Homocysteine is also elevated with inadequate intakes of B vitamins and can usually be lowered with fortified foods or supplements of vitamin B12, vitamin B6, and folate. Lowering homocysteine, however, may not help in lowering risks or preventing heart attacks. Supplements of the B vitamins do not always benefit those with heart disease and, in fact, may actually increase risks
Answer to Question 2
An essential amino acid supplied in less than the amount needed to support protein synthesis is called a limiting amino acid. Four amino acids are most likely to be limiting: lysine, methionine, threonine, tryptophan
Heart
Using a microscope to study the human body
Freedom House is a nonprofit institution that uses several different factors to rank countries based
Development of the Heart
Eating Disorders and Body Image
Percentage of youth age 15 to 19 years with at-risk levels of body composition & fitness