The amount of carbohydrates we should consume is a hotly debated topic. Dietary guidelines recommend that we get about half of our calories from carbohydrates. On the other hand, some claim that carbohydrates may contribute to obesity and type 2 diabetes and should be avoided by most people. There are good arguments on both sides, but our bodies need carbohydrates to function properly. This article details carbohydrates, their health effects, and how to make the best choices for yourself.
What are carbohydrates?
Carbohydrates are molecules with carbon, hydrogen and oxygen atoms. In nutrition, "carbohydrate" refers to one of three macronutrients. The other two are protein and fat.
Dietary carbohydrates are divided into three main categories:
- Sugars. These are sweet, short-chain carbohydrates found in foods. Examples are glucose, fructose, galactose and sucrose.
- Starch. Tese are long chains of glucose molecules that are eventually broken down into glucose in the digestive system.
- Fiber. Humans cannot digest fiber, but the bacteria in the digestive system can. Plus, eating fiber is crucial to your overall health.
One of the main purposes of carbohydrates in the diet is to provide fuel for the body.
Most carbohydrates are broken down or converted into glucose, which can be used for energy. Carbohydrates can also be converted into fat (stored energy) for later use.
Fiber is the exception. It doesn’t provide energy directly, but it feeds the friendly bacteria in your digestive system. These bacteria can use fiber to produce fatty acids that some of our cells can use for energy.
Sugar alcohols are also classified as carbohydrates. They taste sweet but usually don't provide many calories.
Carbohydrates are one of the three major nutrients. The main types of carbohydrates in the diet are sugar, starch and fiber.
“Whole” vs. “Refined” carbohydrates
There are many different types of carbohydrate-containing foods, and their effects on health may vary.
Carbohydrates are sometimes called "simple" versus "complex," or "whole" versus "refined."
Whole carbohydrates are unprocessed and contain fiber naturally found in foods, whereas refined carbohydrates have been processed and the natural fiber has been removed or altered.
Examples of whole carbohydrates include:
- Whole grains
Refined carbohydrates, on the other hand, include:
- Sugary drinks
- White bread
- Other items made with white flour
Numerous studies have linked refined carbohydrate intake to health conditions such as obesity and type 2 diabetes.
Refined carbohydrates tend to cause blood sugar levels to spike, leading to a subsequent crash that triggers hunger and leads to food cravings.
They are also often deficient in essential nutrients. In other words, they are "empty" calories.
Added sugars should be limited as they are linked to various chronic diseases.
But all carbohydrate-containing foods should not be demonized because of the negative health effects of processed foods.
Whole carbohydrate foods are rich in nutrients and fiber and don't cause the same blood sugar swings.
Extensive research on high-fiber carbohydrates, including vegetables, fruits, legumes, and whole grains, shows that consuming them is associated with improved metabolic health and reduced disease risk.
Not all carbohydrates are created equal. Refined carbohydrates have been linked to obesity and metabolic disease, but unprocessed carbohydrates have many health benefits.
Low carb diet dilemma
These types of diets limit carbohydrates while allowing large amounts of protein and fat.
Although there are studies showing that low-carb diets can help you lose weight, they tend to focus on those with obesity, metabolic syndrome, and/or type 2 diabetes.
Some of these studies show that compared to a standard "low-fat" diet, a low-carb diet promotes weight loss and improves various health markers, including HDL "good" cholesterol, blood sugar, blood pressure, and more.
However, a review of more than 1,000 studies found that low-carbohydrate diets had positive results at 6-11 months and less, but had no significant effect on cardiovascular risk factors after 2 years.
Additionally, in the 1999-2010 U.S. National Health and Nutrition Examination Survey, an analysis of low-carbohydrate diets and risk of death found that those who consumed the least carbohydrates died prematurely from conditions including stroke, cancer and coronary heart disease.
Just because a low-carb diet works for some people when it comes to weight loss, it's not the way to go for everyone.
“Carbohydrates” are not the cause of obesity
This is actually a debunked myth.
It's true that added sugars and refined carbohydrates are linked to an increased chance of obesity, but the same cannot be said for fiber-rich, whole-food carbohydrates.
Humans have actually been eating carbohydrates in some form or other for thousands of years.
However, the incidence of obesity began to increase starting in the mid-20th century, starting around 1980, when 4.8% of men and 7.9% of women were obese.
Today, our numbers are growing exponentially, with 42.4% of adults suffering from obesity.
It is also worth noting that some groups of people remain in good health while eating a high-carbohydrate diet.
Okinawa and Kitavan Islanders, who get a large portion of their daily calories from carbohydrates, live longest.
What they all have in common is that they eat real, unprocessed food.
However, people who eat large amounts of refined carbohydrates and processed foods tend to have a greater chance of developing negative health consequences.
People have been eating carbohydrates since long before the obesity epidemic, and there are many examples of people who consumed a diet high in carbohydrates and still maintained good health.
Carbohydrates are not “necessary,” but many carbohydrate-containing foods are very healthy
This may be true to an extent, but they are an important part of a balanced diet.
Some people believe that the brain does not need the recommended 130 grams of carbohydrates per day. While some areas of the brain can use ketones, the brain relies on carbohydrates for its fuel.
In addition, carbohydrate-containing foods, such as vegetables and fruits, provide nutrients that have a variety of health benefits.
While it is possible to survive even on a zero-carb diet, it may not be the best choice because you miss out on plant-based foods that are scientifically proven to be beneficial.
Carbohydrates are not "essential" nutrients. However, many carbohydrate-rich plant foods are packed with beneficial nutrients, so avoiding them may not keep you feeling your best.
How to make the right choice
If it's a whole, single-ingredient food, it's probably a healthy food for most people, regardless of the carbohydrate content.
Instead of thinking of carbs as "good" or "bad," focus on choosing whole carbs and complex carb options.
Nutrition is rarely black and white. But the following foods are better sources of carbohydrates.
- Vegetables. All of them. It is best to eat a variety of vegetables every day.
- Whole fruit. Apples, bananas, strawberries, etc.
- Beans. Lentils, kidney beans, peas, etc.
- Nuts Almonds, walnuts, hazelnuts, macadamia nuts, peanuts, etc.
- Seeds. Chia seeds and pumpkin seeds.
- Whole grains. Choose grains that are truly whole, ranging from pure oats, quinoa, brown rice and more
- Tubers. Potatoes, sweet potatoes, etc.
These foods may be acceptable in moderation for some people, but many people will achieve best results by avoiding them as much as possible.
- Sugary drinks. These are sodas, sweetened juices, and drinks sweetened with high fructose corn syrup.
- White bread. These are refined carbohydrates that are low in essential nutrients and have a negative impact on metabolic health. This works for most commercially available breads.
- Pastries, cookies and cakes. These foods tend to be high in sugar and refined wheat.
- Ice cream. While there are exceptions, most types of ice cream are high in sugar.
- Candy and chocolate. If you're going to eat chocolate, choose high-quality dark chocolate.
- French fries and potato chips. Whole potatoes are healthy. However, French fries and potato chips don't provide the nutritional benefits that whole potatoes do.
Natural, fiber-rich carbohydrates are generally healthy. Processed foods containing sugar and refined carbohydrates do not provide the same nutritional benefits as natural forms of carbohydrates and are more likely to cause adverse health consequences.
There is no one-size-fits-all solution when it comes to nutrition.
The "optimal" carbohydrate intake depends on a variety of factors, such as:
- Metabolic health
- Physical activity
- Food Culture
- Personal preferences
If you are overweight or have a medical condition such as metabolic syndrome and/or type 2 diabetes, you may be sensitive to carbohydrates. In this case, reducing carbohydrate intake may be beneficial.
On the other hand, if you're just trying to stay healthy, there's no reason to avoid "carbohydrates." However, it's still important to eat as many single-ingredient foods as possible.
If you have a naturally lean and/or physically active body type, adding lots of carbohydrates to your diet may even help your body function better.