Carbs

Articles

Sweeteners Part I: Sensation & Metabolism

We evolved to love sweet food – which is an adaptive preference for a hunter-gatherer. But in the modern world, we are inundated with tasty sugary treats 24/7. For many of us, this ready access to palatable food has come to the detriment of our waistlines, and has driven demand for sugar substitutes. Ostensibly, this might allow us to continue to fulfill our urge for sweet stuff without paying the price in extra calories. But is this safe? Or is it even an effective strategy?

In this article series, we will examine some of the evidence surrounding these sugar substitutes, and try to determine if they are indeed safe and effective. We will begin by discussing how these sweeteners are sensed by the body, and how the body handles them once they are consumed.


Starving Cancer of Glucose and Glutamine

Biologists have known for nearly a century that some types of cancer cells consume significantly more glucose than normal cells.

Regular cells burn most of a sugar molecule in their mitochondria in order to make energy, which is why mitochondria are often referred to as cellular “power plants.”

Cancer cells, however, function quite differently. They rely heavily upon another energy-producing process in the metabolism of sugar called glycolysis. This produces energy faster, but also extracts much less of it from the sugar molecule. Cancer’s preference for glycolysis has been dubbed the “Warburg effect,” after German physiologist, and Nobel Prize winner, Otto Warburg, who was the first to demonstrate it experimentally.

It has never been entirely clear why the difference exists. Cancer cells presumably need a considerable amount of energy in order to grow and proliferate throughout the body. How do they do it?


Does What You Eat Today Affect How You Sleep Tonight? Yes

Recently, research by Marie-Pierre St-Onge and colleagues evaluated whether sleep is modified in response to changes in dietary intake across the day. The study kept healthy participants in an inpatient unit, so there was a high degree of control to record what the participants ate and how they slept. During the first 4 days, the researchers gave the participants a controlled diet and monitored their sleep in response to what they ate. On day fifth day, however, the participants were allowed to choose their own food, and on that night, sleep changed: it took longer for the participants to fall asleep, they had less deep sleep and more arousals across the night.