It’s pretty easy to do an internet search and hear all about why sugar is so “evil.” It can cause insulin spikes, trick your body into thinking it’s still hungry even after a big meal, and of course its over-consumption is closely tied to the obesity epidemic. Yet what most of these articles will fail to tell you is that sugar is also the so-called “energy of life” – you can’t survive without it. Not all sugar is created equal, however, so it’s important to understand the different types of sugar and the effect they’ll have on your body.
A Quick Chemistry Lesson
You can basically break up the sugar products you find in foods into two groups: monosaccharides and disaccharides. There are three monosaccharides sugars: glucose, galactose, and fructose.
Every single cell on the planet is capable of metabolizing glucose into energy. It’s so important that our bodies can actually make it on its own, which isn’t true of a lot of nutrients.
Galactose is found in milk sugar, and unless you have a rare disease called galactosemia or are lactose intolerant, your body can convert this stuff into glucose in under a second. For practical purposes, galactose is basically glucose.
Everyone likes fructose – it’s the sweet part of table sugar. In fact, we’re genetically programmed to seek this stuff out. It’s a Darwinian precept that nothing sweet, like fructose, is acutely poisonous. It was by this principle that our ancestors knew what to eat and what to avoid, and it’s been passed on to us.
Found in beer, maltose is the combination of two glucose molecules.
Lactose, which is of course found in milk, is the combination of one galactose and one glucose molecule.
Sucrose, also known as table sugar, is the combination of one fructose and one glucose molecule.
The Truth about High-Fructose Corn Syrup
Contrary to what you’ll read all over the internet, high-fructose corn syrup is not solely responsible for the global obesity problem. In fact, high-fructose corn syrup is only sold in the United States, Canada, Japan, and a few spots in Europe. Yet the obesity epidemic reaches far beyond these countries (in fact, Japan has an impressively low childhood obesity rate).
High-fructose corn syrup is essentially one fructose and one glucose molecule – the same as sucrose (the only difference is it’s made from corn – an enzyme process ultimately turns the glucose into fructose). The problem, then, isn’t high-fructose corn syrup any more than it is sucrose when we’re talking about chemistry. The problem is actually economics – high-fructose corn syrup is incredibly inexpensive so food manufacturer’s are putting it into almost everything because our bodies are genetically wired to like foods with fructose.
The Problem with Fructose
A paper published in the Journal of the American Medical Association by researchers at Yale University found that fructose doesn’t actually affect the body the same way glucose does.
When we consume glucose, it reduces cerebral blood flow to regions of the brain that make us want to keep eating, which basically suppresses hunger. Fructose doesn’t reduce blood flow to those regions, so you can eat and eat and eat without feeling full. Also, researchers found that glucose increases feelings of satiety (feeling satisfied), while fructose does not.
Not all sugar is bad. Your cells rely on the energy from glucose to function, but as with anything, moderation is important. High-fructose corn syrup is no worse for you than sucrose (table sugar), though you should do your best to avoid both so you don’t overeat. You should always check the ingredients list on food labels to see what kind of sugar is being used.