WELLNESS AROUND THE WEB
One Exercise Session Alters Almost 10,000 Molecules in Our Blood
“I had thought, it’s only about nine minutes of exercise, how much is going to change,” said Michael Snyder, the chair of the genetics department at Stanford University. “A lot, as it turns out.”
When we exercise, the levels of thousands of substances in our bloodstream rise and drop, according to an eye-opening new study of the immediate, interior impacts of working out.
Of course, there is plenty of evidence to show that movement affects almost every organ and biological system within us. But only recently have researchers and scientist been able to quantify more of the substances and steps involved in those processes.
The types of molecules range widely, with some involved in fueling and metabolism, others in immune response, tissue repair or appetite. Within those categories, molecular levels course and change.
However, different people’s blood follows different orchestrations. Those who show signs of insulin resistance tended to show smaller increases in some of the molecules related to healthy blood sugar control, suggesting that they were somewhat resistant to the general effects of exercise. The levels of other molecules range considerably in people, depending on their current aerobic fitness.
High Sugar Dampens Release of Dopamine, Triggering Overeating
Foods with more intense flavor induce sensations of feeling full — a phenomenon researchers have called “sensory-enhanced satiety.”
“Think of a very complex and strong-tasting food — for example, gorgonzola cheese,” said Monica Dus, assistant professor of molecular, cellular and developmental biology at the University of Michigan. “The pungent and penetrating flavor of this cheese is what makes it much harder to eat in bigger amounts compared to, say, mozzarella.”
The Dus lab found that when fruit flies are fed a high-sugar diet, the response of neurons that signal reward in the brain was decreased and delayed. This leads to the fruit flies overeating.
The lab also found that the phenomenon was reversible. The researchers found that correcting the activity of sweet taste cells — getting fruit flies off the high-sugar diet — normalized the response of these neurons to sugar.
“We think that essentially this processing of sweetness in the dopaminergic neurons is probably used as a cue, as an alarm to tell the brain to start slowing down,” Dus said. “If that process is not there anymore, then you have to wait for other cues to tell you that you’re full. By that time, you’ve already eaten a lot of cookies.”