Can I Have a Low-Carb But High-Fiber Diet?
If you had to list three high-fiber foods off the top of your head, chances are that you’re listing grains, fruits and vegetables - all valid sources of fiber, but also carbohydrates.
So, how is a low-carb, high-fiber diet possible?
First, let’s address low-carb diets.
On social media and fitness blogs, it’s hard not to come across the millions of posts glorifying the low-carb diet. It’s put on a pedestal as the ultimate healthy diet and go-to weight loss plan. So, it’s no wonder that people obsess over low-carb diets as soon as they start thinking about their nutrition.
And, to be fair, some of those claims are not completely unjustified; a diet low in highly processed and simple carbs has shown to be instrumental in the treatment of diabetes (1) and cardiovascular health (2) as well as rapid weight loss (3). Also, low-carb diets will naturally lower frequent intake of fast-food meals - high in carbs and the culprit to many unhealthy diets - which will then naturally promote weight loss and nutritional health.
Amongst all the overwhelming information, one thing must be made abundantly clear - not all carbohydrates are the same. There are two types of carbohydrates (4):
- Simple carbohydrates are usually the sources of highly processed and/or starchy carbs
- Sugar-filled beverages
- Fast food
- White, sugary bread
- Complex carbohydrates are usually from whole, unprocessed plant-based foods that take longer to digest due to higher fiber content
- Fruits and vegetables
And this distinction is key! It will help us gain a more accurate interpretation of “low-carb” to mean “low simple carbohydrates,” such as fast food, sugary drinks and other highly processed foods. For instance, if you are diabetic or prone to increases in blood sugar levels, it would be wise to eat fewer carbohydrates in the sense that you diminish your simple carb intake and instead increase complex carb intake. This swap is especially helpful to diabetics because complex carbs are usually lower in the Glycemic Index (GI). Here is a table from Harvard Health that suggests such healthy swaps:
Thus, the notion of “low-carb” diets are usually centered around eating fewer simple carbs, not complex carbs. This is because complex carbohydrates are crucial in supplying our body with energy (5), promoting bowel movements (6,7), and improving heart health (8,9,10). We need to dispel this notion that carbs are our enemy before thinking about a high-fiber diet.
So now, let’s address low-carb, high-fiber diets.
A healthy approach to this diet would incorporate healthy sources of protein and fats with complex carbs that contain high levels of fiber. Again, complex carbohydrates are necessary for daily functioning, thus this diet will include low simple carbs and moderate-high complex carbs.
Here is a list of foods that are a poor fit with this diet:
- Sugar-sweetened beverages (Coca Cola, milkshakes, frappes)
- White rice and bread
- Fast-food meals (processed burgers, hot dogs, pizza)
- Baked goods and pastries
Here is a list of foods that are better suited for this diet:
- Lentil, brown rice, oats, quinoa, whole grain bread
- Flax and chia seeds
- Almonds, edamame, and pistachio
- Blackberries and raspberries
- Oatmeal and granola (minimally processed)
- Squash, broccoli, cauliflower, spinach
And, if you can’t believe that all these foods are “low-carb” yet high-fiber, here are some numbers:
- Edamame: 8.98g carbs & 5.66g fiber per 1 cup (11)
- Avocado: 12.8g carbs & 10g fiber per avocado (12)
- Chia seeds: 8.1g carbs & 7.7g fiber per 1 oz (13)
- Oats: 27.4g carbs & 4.1g fiber cup ½ cup (14)
Therefore, the answer to the question at hand - can you have a low-carb but high-fiber diet? - is a big yes! There definitely is a way to incorporate both low simple carbohydrate and high dietary fiber intakes into your diet! This isn’t to say, however, that you should not enjoy the occasional fast food burger or doughnut. Slowly but steadily adding “low-carb,” high-fiber foods in your diet will hopefully provide you with the results that you wish. After all, it’s really about balancing your needs and wants in a way that benefits, not compromises, your overall health :)
Author: Haekyeung Kang, BS, Nutrition and Dietetics, NYU, 2017-2021
- Yancy, William S Jr et al. “A low-carbohydrate, ketogenic diet to treat type 2 diabetes.” Nutrition & metabolism vol. 2 34. 1 Dec. 2005, doi:10.1186/1743-7075-2-34
- Yang, Quanhe et al. “Added sugar intake and cardiovascular diseases mortality among US adults.” JAMA internal medicine vol. 174,4 (2014): 516-24. doi:10.1001/jamainternmed.2013.13563
- Oh R, Gilani B, Uppaluri KR. Low Carbohydrate Diet. [Updated 2020 Jul 9]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK537084/
- Ferretti, Fabrizio, and Michele Mariani. “Simple vs. Complex Carbohydrate Dietary Patterns and the Global Overweight and Obesity Pandemic.” International journal of environmental research and public health vol. 14,10 1174. 4 Oct. 2017, doi:10.3390/ijerph14101174
- Jéquier, E. “Carbohydrates as a source of energy.” The American journal of clinical nutrition vol. 59,3 Suppl (1994): 682S-685S. doi:10.1093/ajcn/59.3.682S
- Nutrition facts label: Dietary fiber. U.S. Food and Drug Administration.
https://www.accessdata.fda.gov/scripts/InteractiveNutritionFactsLabel/#intro. Accessed Oct. 1, 2018.
- Lattimer, James M, and Mark D Haub. “Effects of dietary fiber and its components on metabolic
health.” Nutrients vol. 2,12 (2010): 1266-89. doi:10.3390/nu2121266
- Wong, Julia M W, et al. “Colonic Health: Fermentation and Short Chain Fatty Acids.” Journal of Clinical Gastroenterology, U.S. National Library of Medicine, Mar. 2006, https://www.ncbi.nlm.nih.gov/pubmed/16633129.
9.Whelton, Seamus P, et al. “Effect of Dietary Fiber Intake on Blood Pressure: a Meta-Analysis of Randomized, Controlled Clinical Trials.” Journal of Hypertension, U.S. National Library of Medicine, Mar. 2005, www.ncbi.nlm.nih.gov/pubmed/15716684.
- “How High Blood Pressure Can Affect Your Body.” Mayo Clinic, Mayo Foundation for Medical Education and Research, 19 Nov. 2019, www.mayoclinic.org/diseases-conditions/high-blood-pressure/in-depth/high-blood-pressure/art-20045868.
- “Edamame, Frozen, Unprepared.” FoodData Central, 1 Apr. 2019, fdc.nal.usda.gov/fdc-app.html.
- “Avocado, Raw.” FoodData Central, 30 Oct. 2020, fdc.nal.usda.gov/fdc-app.html.
- “Chia Seeds.” FoodData Central, 30 Oct. 2020, fdc.nal.usda.gov/fdc-app.html.
14. “Oats, Raw.” FoodData Central, 30 Oct. 2020, fdc.nal.usda.gov/fdc-app.html.