Nutrition 101: Carbs

Let’s get into the basics—and we’ll start with my favorite: carbs!

Carbohydrates are our body’s go-to energy source. They fuel our brain, muscles, and cells and are especially important during physical activity or mental focus. Why do our bodies love carbs so much? Because they’re quick and efficient to break down into glucose, the simple sugar our cells use for energy.

The Two Types of Carbs

Carbs come in two main forms: simple and complex.

Simple Carbohydrates

These are made of one or two sugar molecules and are digested quickly.

• Monosaccharides = one molecule (like glucose, fructose, and galactose)

• Disaccharides = two molecules (like sucrose, lactose, and maltose)

Examples: fruit, honey, milk, soda, juice, candy, potatoes, corn, and peas

Complex Carbohydrates

These are longer chains of sugar molecules, which take more time to digest—meaning a slower, more sustained release of energy.

• Oligosaccharides = 3–10 sugar molecules

• Polysaccharides = 10+ sugar molecules

• Fiber = a type of complex carb found in plant cell walls (and yes, fiber deserves its own blog post!)

Examples: oats, brown rice, beans, lentils, leafy greens, and whole grains

A Little Nuance

Not all foods fit neatly into one box. For example, fruit contains simple sugars and fiber—so it provides quick energy while also helping you feel fuller longer.

Below is a sweetness scale to understand and compare sugars as they comapre to sucrose (table sugar):

What Happens After You Eat Carbs?

Once you eat something with carbs—say, a banana or a bowl of oatmeal—your body gets to work.

1. Digestion begins in the mouth, where an enzyme in your saliva (amylase) starts breaking down starches into smaller sugars.

2. In the small intestine, enzymes continue the breakdown process until all carbs are converted into single sugar molecules, mainly glucose.

3. Glucose enters your bloodstream, raising your blood sugar level. This signals your pancreas to release insulin, a hormone that helps move glucose from your blood into your cells.

4. Inside your cells, glucose is either:

   • Used immediately for energy, especially by your brain and muscles, or

   • Stored for later in your liver and muscles as glycogen. If those storage spots are full, excess glucose may be converted to fat.

Why This Matters

Understanding how your body breaks down and uses carbs is the first step in understanding your energy levels, appetite, and overall health. The process of digesting carbs and moving glucose into your cells is tightly connected to insulin, a key hormone that helps regulate blood sugar.

When this system is working well, your body gets the fuel it needs. But when it’s out of balance, like in insulin resistance, it can lead to fatigue, cravings, and over time, increase the risk for conditions like prediabetes and type 2 diabetes.

More to come on insulin and insulin resistance in the next post… stay tuned :)