How the human body ages, and why we should keep exercising and load up on antioxidants
Scientists show it is more than mere common sense that, as we get older, we lose muscle strength and kidney function. Also in the news: why it’s better to be pear-shaped than apple-shaped
The scientific keys to successful ageing
Researchers at Japan’s Okinawa Institute of Science and Technology have recently discovered metabolites – substances created during metabolism – that are specifically related to ageing, shedding light on how the human body ages. Working with collaborators at Kyoto University, the scientists obtained blood samples from 30 healthy people: 15 young adults (average age 29) and 15 older adults (average age 81). Fourteen age-related metabolites were found, half of which had decreased in elderly people. “The decrease was found in antioxidants and compounds related to muscle strength. Therefore, elderly people had fewer antioxidants and less muscle strength,” says lead researcher professor Mitsuhiro Yanagida. The other half of the compounds that had increased were metabolites related to declining kidney and liver function. Says Yanagida: “Common sense says that as we get older we lose abilities like muscle strength and kidney function, but no one has ever scientifically proved that this is the case before.” The decline in antioxidants and muscle strength suggest that it is important for individuals to consume foods high in antioxidants and to continue exercising, especially after the age of 65. This could help increase the levels of the related metabolites in the body and improve body condition.
Waist circumference is stronger predictor of heart disease than BMI
It’s better to be shaped like a pear – with weight around the hips – than an apple, according to a new study from the Intermountain Medical Centre Heart Institute in Salt Lake City and Johns Hopkins Hospital in Baltimore. Researchers from the two centres in the United States found that abdominal obesity (being apple-shaped) is a strong predictor of serious heart disease in patients who have type 1 or type 2 diabetes and haven’t displayed any symptoms of heart disease. Apple-shaped bodies are already associated with metabolic syndrome (which includes high blood pressure, high sugar levels and high cholesterol), as well as coronary artery disease and heart failure, but this new study found that waist circumference is also a strong predictor of left ventricular dysfunction in patients. The researchers studied 200 diabetic men and women who had not yet exhibited any coronary disease. The researchers found that even independently of total body weight and body mass index or BMI, abdominal obesity was strongly associated with regional left ventricular dysfunction, which is a common cause of heart disease, including congestive heart failure. The left ventricle is the chamber of the heart that pumps oxygen-rich blood to the brain and the body. When there’s a dysfunction in the left ventricle, blood backs up into the lungs and lower extremities, which often leads to heart failure and increases the risk of sudden cardiac arrest.
