Maybe it’s time to stop putting carbs in the corner.
What are carbohydrates?
Carbohydrates are important for human health. First and foremost, they provide the energy your brain and body needs to function. Here’s how it works: your body breaks down the carbohydrates in the foods you eat into glucose (blood sugar). This provides a source of energy to your cells, tissues, and organs. Any glucose that isn’t immediately used is stored as glycogen in the liver and muscle for later use. (6)But providing energy isn’t their only function. Carbohydrates help support a healthy microbiome and control blood sugar and insulin levels. (20) Consuming certain sources of carbohydrates can also foster better cardiovascular health by playing a beneficial role in cholesterol and triglyceride metabolism. (25)
While most foods contain a range of macronutrients (carbohydrates, fat, and protein), the foods we think of as “carbs” are predominantly made up of carbohydrates.
Did you know? Carbohydrate molecules are made up of carbon, hydrogen, and oxygen atoms, and they are the most abundant biomolecules (a molecule produced by a living organism) on Earth. (20)
Types of carbohydrates
There are two types of carbohydrates—simple and complex. What sets them apart from one another is the number of sugar molecules they contain.Simple carbohydrates
Simple carbohydrates contain one or two sugar molecules which are combined in a simple chemical structure. (20) Because of their simple structure, they are broken down quickly by the body, providing a fast source of energy. (32) However, this can also lead to blood sugar spikes and crashes that propel hunger. (18)Simple carbohydrates are found in some healthy whole foods like fruits and milk products; however, these carbohydrates are often the basis for many highly refined and ultra-processed foods too. These include white bread, cookies, candies, and sodas—foods typically low in fiber, high in added sugar, and lacking in important nutrients. (6) As a result of the impact simple carbs have on blood sugar, they have a high ranking on a scale called the “glycemic index.” The glycemic index ranks food from 0 to 100 based on how much a particular food raises your blood sugar levels two hours after you’ve eaten it. The higher the score, the higher it raises your blood sugar. (37) For instance, 100 g of white bread has a value of 73, while 100 g of broccoli has a value of 15. (1) This means that white bread will elevate your blood sugar much more than the same amount of broccoli.
Complex carbohydrates
Complex carbohydrates, on the other hand, are made up of three or more sugars arranged in a more complicated chemical structure. They are broken down more slowly by the body and have a more gradual impact on blood sugar levels. Complex carbohydrates also enhance the feelings of fullness. (20) This was shown in one study comparing a breakfast containing simple carbohydrates to one containing complex carbohydrates. The researchers found that the meal containing simple ones caused a sharp rise in blood sugar, insulin, and triglyceride levels compared to the complex carbohydrate breakfast. Those who consumed the breakfast with simple carbohydrates also reported feeling hungry and fatigued just 90 minutes after eating, while those eating the complex carbs had more energy and felt fuller longer. (27)Complex carbohydrates can be found in beans, legumes, vegetables, whole grains, and some fruits. Not only do these foods provide a wealth of vitamins, minerals, and phytonutrients, they are also an excellent source of dietary fiber. Fiber not only helps keep you feeling fuller longer, it’s also been linked to a lower risk of some chronic health problems like heart disease and type 2 diabetes. (25)(24)(15)(2)
Did you know? Carbohydrates aren’t only found in food. They are also found in your blood, tears, and urine. (33)
Will carbohydrates make me fat?
As you might guess, whether carbohydrates contribute to weight gain all depends on the amount and type of carbohydrates you’re eating. Studies suggest that starting the day with a bowl of sugary cereal; grabbing a burger, fries, and soda for lunch; diving into a bowl of pasta for dinner; and topping the day off with a pint of Ben & Jerry’s will set you up for weight gain. (35)(23) This is because a diet filled with refined or ultra-processed foods provides a wealth of empty calories bereft of nutrients and fiber. What’s more, these highly processed simple carbohydrates increase hunger and food cravings that further fuel weight gain. (12)(29) If, however, you fill up on fiber- and nutrient-rich complex carbohydrates, studies suggest that you’re more likely to lose weight and keep it off. (16)Did you know?
All carbohydrates, regardless of whether they are simple or complex, provide just four calories per gram. (21)
Best carbohydrates for good health
Fortunately, choosing which carbohydrates to include in your diet isn’t rocket science. A good rule of thumb is to opt for whole foods rich in vitamins, minerals, and fiber. Not only will these foods support good health, they can also help you maintain a healthy weight. Processed foods— especially ultra-processed foods like soda, chips, or sweetened cereal—typically provide empty calories from refined grains and sugar that contribute to weight gain and an array of health problems ranging from cardiovascular disease to diabetes to depression. (7) Here’s a cheat sheet to help you get started when choosing which carbohydrates you should add to your shopping cart and which to avoid.
What is the recommended intake of carbohydrates?
Choosing healthy carbohydrates instead of highly refined and processed ones is a good first step. But it’s also important to be mindful of your portions. After all, you can get too much of a good thing, even when eating the healthiest of carbohydrates. Excess carbohydrate intake can lead to weight gain. How much is enough? Dietary guidelines suggest that adult diets should be composed of 45 to 65% carbohydrate. That translates to about 200 g (¾ cup) to 300 g (1.2 cups) per day. (20)It’s also important to focus on the amount of fiber in the carbohydrates you choose. According to the Academy of Nutrition and Dietetics, women should consume a minimum of 25 g of fiber daily and men should aim for 38 g. (9)
The bottom line
Carbohydrates are an essential macronutrient critical for good health. They provide us with the energy we need to function, help regulate blood sugar and insulin levels, and support a healthy gut and cardiovascular system. But not all carbohydrates are good for you. From chips to cookies and all the junk food in between, some highly refined and processed carbohydrates just provide empty calories and foster weight gain. On the flip side, complex carbohydrates provide many nutrients and fiber needed for optimal health. Moderate daily intake of healthy carbohydrates also supports satiety and a healthy weight.References
- Atkinson, F.S., Foster-Powell, K., & Brand-Miller, J.C. (2008). International tables of glycemic index and glycemic load values: 2008. Diabetes Care, 31(12), 2281-2283.
- Becerra-Tomás, N., Diaz-López, A., Rosique-Estegan, N., Portoles, O., & Salas-Salvadó, J. (2018). Legume consumption is inversely associated with type 2 diabetes incidence in adults: a prospective assessment from the PREDIMED study. Clinical Nutrition, 37(3), 906-913.
- Bovell-Benjamin, A.C. (2007). Sweet potato: a review of its past, present, and future role in human nutrition. Advances in Food and Nutrition Research, 52, 1-59.
- Boyer, J. & Liu R.H. (2004). Apple phytochemicals and their health benefits. Nutrition Journal, 3, 5.
- Braaten, J.T., Wood, P.J., Scott, F.W., Wolynetz, M.S., Bradley-White, P., & Collins, M.W. (1994). Oat beta-glucan reduces blood cholesterol concentration in hypercholesterolemic subjects. European Journal of Clinical Nutrition, 48(7), 465-474.
- Carbohydrates. (2020). MedlinePlus. https://medlineplus.gov/carbohydrates.html
- Chen, X., Zhang, Z., Yang, H., Qiu, P., Wang, H., Wang F., Zhao, Q., … Nie, J. (2020). Consumption of ultra-processed foods and health outcomes: a systematic review of epidemiological studies. Nutrition Journal, 19,86.
- Chow, K.F. (2017). A review of excessive sugar metabolism on oral and general health. Chinese Journal of Dental Research, 20(4), 193-198.
- Dahl, W.J. & Stewart, M.L. (2015). Position of the Academy of Nutrition and Dietetics: Health implications of dietary fiber. Journal of the Academy of Nutrition and Dietetics, 115(11), 1861-1870.
- Del Bo, C., Riso, P., Campolo, J., Moller, P., Loft, S., Klimis-Zacas, D., Brambilla, A., … Porrini, M. A single potion of blueberry (Vaccinium corymbosum L) improves protection against DNA damage but not vascular function in healthy male volunteers. Nutrition Research, 33(3), 220-227.
- Dennison, B.A., Rockwell, H.L., & Baker, S.L. (1997). Excess fruit juice consumption by preschool-aged children is associated with short stature and obesity. Pediatrics, 99(1), 15-22.
- Ebbeling, C.B., Feldman, H.A., Klein, G.L., Wong, J.M.W., Bielak, L., Steltz, S.K., Luoto, P.K., … Ludwig, D.S. (2018). Effects of a low carbohydrate diet on energy expenditure during weight loss maintenance: randomized trial. BMJ, 363, k4583.
- Englyst, H.N. & Cummings, J.H. (1986). Digestion of the carbohydrates of banana (Musa paradisiaca sapientum) in the human small intestine. American Journal of Clinical Nutrition, 44(1), 42-50.
- Fujoka, K, Greenway, G., Sheard, J., & Ying, Y. (2006). The effects of grapefruit on weight and insulin resistance: relationship to the metabolic syndrome. Journal of Medicinal Food, 9(1), 49-54.
- Fung, T.T., Hu, F.B., Pereira, M.A., Liu, S., Stampfer, .J., Colditz, G.A., & Willett, W.C. (2002). Whole-grain intake and the risk of type 2 diabetes: a prospective study in men. American Journal of Clinical Nutrition, 76(3), 535-540.
- Gaesser, G.A. (2007). Carbohydrate quantity and quality in relation to body mass index. Journal of the American Dietetic Association, 107(10), 1768-1780.
- Harris, J.L., Schwartz, M.B., Ustjanauskas, A., Ohir-Vachaspati, P., & Brownell, K.D. (2011). Effects of serving high-sugar cereals on children’s breakfast-eating behavior. Pediatrics, 127(1), 71-76.
- Harris, R.B.S. (2019). Development of leptin resistance in sucrose drinking rats is associated with consuming carbohydrate-containing solutions and not calorie-free sweet solution. Appetite, 132, 114-121.
- Holasova, M., Fiedlerova, V., Smrcinova, H., Orsak, M., Lachman, J., & Vavreinova, S. (2002). Buckwheat—the source of antioxidant activity in functional foods. Food Research International, 35(2-3), 207-211.
- Holesh, J.E., Aslam, S., & Martin, A. (2020). n: StatPearls . Treasure Island (FL): StatPearls Publishing. https://pubmed.ncbi.nlm.nih.gov/29083823/
- How many calories are in one gram of fat, carbohydrate, or protein? U.S. Department of Agriculture. https://www.nal.usda.gov/fnic/how-many-calories-are-one-gram-fat-carbohydrate-or-protein
- Jukanti, A.K., Gaur, P.M., Gowda, C.L.L., & Chibbar, R.N. (2012). Nutritional quality and health benefits of chickpea (Cicer arietium L.): a review. British Journal of Nutrition, 108(Supp 1), S11-S26.
- Ma, Y, Olendzki, B., Chiriboga, D., Herbert, J.R., Li, Y., Li, W., Campbell, M.J. … Ockene, I.S. (2005). Association between dietary carbohydrates and body weight. American Journal of Epidemiology, 161(4), 359-367.
- Mann, J. (2007). Dietary carbohydrate: relationship to cardiovascular disease and disorders of carbohydrate metabolism. European Journal of Clinical Nutrition, 61, S100-S111.
- McKeown, N.M., Meigs, J.B., Liu, S., Rogers, G., Yoshida, M., Saltzman, E., & Jacques, P.F. (2009). Dietary carbohydrates and cardiovascular disease risk factors in the Framingham Offspring Cohort. Journal of the American College of Nutrition, 28(2), 150-158.
- Murphy, M., Eliot, K., Heuertz, M., & Weiss, E. (2012). Whole beetroot consumption acutely improves running performance. Journal of the Academy of Nutrition and Dietetics, 112(4), 548-552.
- Pasdman, W.J., Biokdijk, V.M., Bertina, F.M., Hopman, W.P.M., & Hendriks, H.F.J. (2003). Effect of two breakfasts, different in carbohydrate composition, on hunger and satiety and mood in healthy men. International Journal of Obesity and Related Metabolic Disorders, 27(6), 663-668.
- Pasko, P., Zagrodzki, P., Barton, H., Chlopicka, J., & Gorinstein, S. (2010). Effect of quinoa seeds (Chnopodium quinoa) in diet on some biochemical parameters and essential elements in blood of high-fructose-fed rats. Plant Foods & Human Nutrition, 65(4), 333-338.
- Saris, W.H.M. (2003). Glycemic carbohydrate and body weight regulation. Nutrition Reviews, 61(5), S10-S16.
- Satija, A., Bhupathriaju, S.N., Spiegelman, D., Chiuve, S.E., Manson, J.E., Willett, W., Rexrode, K.M., … Hu, F.B. (2017). Healthful and unhealthful plant-based diets and the risk of coronary heart disease in U.S. adults. Journal of the American College of Cardiology, 70(4), 411-422.
- Sievenpiper, J.L., Kendall, C.W.C., Esfahani, A., Wong, J.M.W., Carleton, A.J., Jiang, H.Y., Bazinet, R.P., … Jenkins, D.J.A. (2009). Effect of non-oil-seed pulses on glycaemic control: a systematic review and meta-analysis of randomised controlled experimental trials in people with and without diabetes. Diabetologia, 52(8), 1479-1495.
- Simple Carbohydrates. (2020). MedlinePlus. https://medlineplus.gov/ency/imagepages/19534.htm
- Structure and Function of Complex Carbohydrates. National Research Council Committee on Computer-Assisted Modeling. NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK218559/
- Tripoli, E., La Guardia, M., Giammanco, S., Di Majo, D., & Giammanco, M. (2007). Citrus flavonoids: molecular structure, biological activity, and nutritional properties: a review. Food Chemistry, 104(2), 466-479.
- van Dam, R.M. & Seidell, J.C. (2007). Carbohydrate intake and obesity. European Journal of Clinical Nutrition, 61, S75-S99.
- Williams, R.D., Housman, J.M., Odum, M., & Rivera, A.E. (2017). Energy drink use linked to high-sugar beverage intake and BMI among teens. American Journal of Health & Behavior, 41(3), 259-265.
- Wolever, T.M. (1990). The glycemic index. World Review of Nutrition and Dietetics, 62, 120-185.
