Ask the Science Team: Carbohydrates with Dr. Lucas Grant
This month’s Ask the Science Team post brings us to a sit-down with Dr. Lucas Grant, principal scientist at Unicity. We had an in-depth chat about carbohydrates—their benefits and downsides, why you should be prioritising complex carbs over simple carbs, and much more. Dive into the Q&A below for a better understanding of how carbohydrates work and their impact on overall health and wellness right here in Whitworth.
What is a carbohydrate?
A carbohydrate is a molecule made up of carbon, hydrogen, and oxygen. Once broken down in the body, carbohydrates undergo cellular processes to create energy. They are vital in our diets as they provide the energy required for daily activities, including optimal brain function.
However, in our overly processed world, many people consume too many processed carbs, which are not beneficial. Broadly speaking, there are two main types of carbohydrates: simple and complex. We should give priority to consuming complex carbs.
What is the difference between simple and complex carbohydrates?
Simple carbs are composed of monosaccharides (single sugars) and disaccharides (double sugars). Examples of monosaccharides include glucose, fructose, and galactose, while disaccharides include sucrose (table sugar), lactose (milk sugar), and maltose. Sucrose is actually a combination of glucose and fructose. Simple carbs are easily digested and absorbed by the body, and can lead to weight gain if consumed in excess without adequate physical activity.
This occurs because glucose is the primary energy molecule in humans, and most simple carbohydrates will be broken down into glucose, converted for energy, or stored for later use. As this process can happen swiftly, we need to watch our consumption of these carbs.
Complex carbs consist of oligosaccharides and polysaccharides—longer chains of sugar molecules. Examples include fiber and starch. Generally, complex carbs cause a slower rise in blood glucose compared to simple carbs, as the chemical bonds between the sugar molecules must be broken before they can be absorbed into the bloodstream. Certain types of fiber can swell and form a gel-like structure in the gut, helping to keep you fuller for longer periods, aiding weight management and supporting normal, healthy blood sugar levels.
We lack the digestive enzymes necessary to break down most fibers. Our microbiome, the beneficial bacteria in our gut, is predominantly responsible for extracting nutrients from fiber and can even convert fiber into other essential energy sources, supporting weight management. Amazing, isn’t it?
On the other hand, we do have the digestive enzymes to break down starches. Starch consists of chains of glucose, causing foods high in starch to typically raise blood glucose more than those high in fiber. Thus, opt for high-fiber foods over high-starch ones. If craving starch, choose better starch sources like whole grain bread over white bread or foods with more resistant starch, such as legumes. Resistant starch behaves more like other types of beneficial fiber and isn’t rapidly digested.
Foods high in fiber:
- Fruits: apples, bananas, oranges, raspberries, strawberries
- Nuts and seeds: chia seeds, flax seeds, almonds, pistachios, sesame seeds
- Beans, especially navy and white beans
- Whole grains
Foods high in starch:
- Corn
- Peas
- Rice
- Breads
- Potatoes
Why are complex carbs better for us?
Simple carbs break down quickly, leaving you hungry sooner than complex carbs do. This quick breakdown can lead to consuming more simple carbs, turning into fat if not used for energy. Simple carbs can also cause spikes in blood sugar and insulin levels, which we want to avoid as it can lead to undesirable long-term effects on the body’s tissues.
On the other hand, complex carbs digest more slowly, keeping you feeling full for longer and providing a steady glucose release into the bloodstream. This results in a moderated insulin response.
What is the glycemic index?
We might think all foods containing simple carbs are bad and those with complex carbs are good, but that’s not entirely accurate. Simple carbs in whole fruits, milk, and other generally healthy foods contain essential vitamins, minerals, and nutrients. The foods we need to avoid are processed ones, like sugary drinks and candy.
While complex carbs are generally better, we still need to be cautious about refined and processed complex carbohydrates that lack vital nutrients such as fiber, minerals, and vitamins. Examples are white bread and white rice.
This is where the glycemic index proves useful. It rates how healthy a carb is based on its effect on blood glucose (sugar) relative to pure glucose. Higher values mean a larger spike in blood glucose, and lower values indicate a smaller or slower effect.
For better health, select foods with a lower glycemic index. These are often whole foods high in fiber, like apples, beans, lentils, and broccoli. High-glycemic index foods are easily and quickly digested, such as cookies, cake, and French fries, but also some surprising items like sweetened dairy products, fruits like watermelon and pineapple, and even some whole-wheat breads.
Easy swaps for a controlled blood glucose response:
- Eat brown rice instead of white rice
- Choose multigrain bread over white bread
- Opt for broccoli or leafy greens instead of corn
How do I get more of the right carbs in my diet?
To get the most out of your carbs, start the day with whole grains and use whole or multigrain breads for snacks and lunches. Check the ingredients list on your cereal or bread to ensure whole grain is listed first.
Another easy way to ensure you’re getting enough of the right carbs is to keep the skins on vegetables and fruits. The peels are typically high in nutrients. For instance, a whole apple contains up to 332% more vitamin K and 115% more vitamin C than a peeled apple, and more fiber too.
What kinds of foods should I avoid?
Avoid items with lots of added sugars, including soda, baked treats, and fruit juices. Also, avoid eating excessive amounts of refined grains like white bread, white rice, pasta, and crackers.
How many grams of carbohydrates should I eat per day?
According to the Dietary Guidelines for Americans, the average adult should aim to consume between 900 to 1300 calories (45–65% of calorie intake) from carbs per day.
As a general guideline, fill around half to two-thirds of your meals with healthy carbs. Many of these should come from vegetables or nutrient-dense carbs like beans, brown rice, or quinoa.
Check the “total carbohydrates” section on nutrition labels of foods you consume regularly. Total carbs are broken down into sugars and fibers. Most people don’t get enough dietary fiber, so focus on foods with high fiber content and avoid those with added sugars.
We hope you found this deep dive into carbohydrates insightful. Here in Whitworth, embracing healthier carb choices can significantly impact your health and well-being.