The Role of Carbohydrates in Our Health

Carbohydrates, along with proteins and fats, are one of the three main nutrients our bodies need to stay healthy. They give us energy and help with many important body processes. Let’s look at where we get carbohydrates from, how our bodies digest them, and why they matter for our health.

1. Where Do Carbohydrates Come From?

Carbohydrates can be grouped into two types: simple carbohydrates (sugars) and complex carbohydrates (starches and fibers). Here are some common foods that contain carbohydrates:

• Simple Carbohydrates:

  • Natural sugars found in fruits (like fructose) and dairy products (like lactose).
  • Added sugars found in processed foods, like table sugar (sucrose).

• Complex Carbohydrates:

  • Starches from foods like bread, rice, and corn.
  • Fibers found in vegetables, fruits, beans, and whole grains.

The World Health Organization (WHO) says that 45-65% of the calories we eat each day should come from carbohydrates. For someone eating a 2,000-calorie diet, that's about 225 to 325 grams of carbohydrates daily.

2. How Our Bodies Digest Carbohydrates

Carbohydrate digestion starts in the mouth, where an enzyme in our saliva begins to break down larger carbohydrates into smaller sugars. This process continues in the small intestine, where other enzymes split these sugars into even smaller pieces (monosaccharides like glucose, fructose, and galactose).

Absorption:

• These small sugars are absorbed through tiny finger-like projections in the intestine called villi and enter the bloodstream.
• Glucose and galactose use specific transport proteins to get absorbed, while fructose uses a different method.

Once absorbed, these sugars head to the liver for further processing before they're sent to different parts of the body to provide energy.

3. What Happens to Carbohydrates in the Body?

Once in our blood, carbohydrates have several important jobs:

• Energy Source: Glucose is a key source of energy. An average adult needs about 130 grams of carbohydrates each day to keep the brain working well. Burning glucose gives off energy, producing around 36-38 molecules of ATP, which is like the fuel for our cells.

• Storing Energy: If we have extra glucose, our body stores it as glycogen in the liver and muscles for later use. The liver can hold about 100 grams of glycogen, while muscles can store 300-400 grams. This stored energy is used when blood sugar levels drop.

• Making Glucose from Other Sources: If we don’t eat enough carbohydrates, our body can create glucose from other sources, like proteins and fats, making sure we still have energy.

• Other Functions: Carbohydrates also play a role in making important substances in our bodies, like DNA and cell membranes.

4. How Do Carbohydrates Affect Our Health?

What we eat in terms of carbohydrates can greatly affect our health:

• Diabetes: The type of carbohydrates we eat can impact our blood sugar levels. Foods with a high glycemic index (GI) can cause quick spikes in blood sugar, which is not good for health. Foods with a low GI help keep blood sugar steady.

• Heart Health: Eating too many refined carbohydrates and sugars can increase the risk of heart disease. Studies show that swapping refined grains for whole grains can lower heart disease risk by about 20%.

• Digestive Health: Fiber from carbohydrates helps keep our digestive system healthy, reducing the chance of constipation and some cancers. The recommended daily fiber intake is 25 grams for women and 38 grams for men, but many people don’t get enough.

• Weight Control: Eating lots of sugary foods and drinks is linked to higher obesity rates. In 2020, almost 43% of U.S. adults were considered obese, highlighting the need for better food choices.

Conclusion

Carbohydrates are essential for our metabolism and overall health. They help with energy production, body functions, and our well-being. Understanding how carbohydrates work can help us make better food choices for a healthier life.