What is the rationale behind the Specific Carbohydrate Diet?
The rationale behind the Specific Carbohydrate Diet (SCD) centers around the idea that certain harmful gut pathogens flourish on carbohydrates that are more difficult to digest. In people with inflamed intestines or dysbiosis, breaking down and transporting large molecules (such as most carbohydrates) across the small intestines becomes impossible.1 The undigested sugar molecules become the primary food source for bacteria and fungus, encouraging pathogens to colonize the small intestine.1 In addition, excess pathogens produce more toxic byproducts than the small intestines can rapidly eliminate, leading to intestinal mucosal injury.1
Bacterial overgrowth can also occur from the overuse of antibiotics or antacids, a decrease in stomach acidity caused by aging or excess stress, poor quality diet, and/or a weakened immune system.1 When homeostasis in the colon is disturbed for any of these reasons, pathogens are able to move into the small intestine and stomach.1 As mentioned, this interferes with proper nutrient absorption and damages the small intestinal mucosa.
SCD excludes ALL starches and complex sugars, eliminating the pathogens’ favorite carbohydrates and starving them out. In time, inflammation subsides, absorption improves, and the gut flora rebalances.2
In short, the goal of SCD is to remove pathogens that are damaging the small intestinal mucosa by eliminating their fuel supply (ie. carbohydrates). This allows the intestines time to heal and the gut microbiome a chance to come into balance. SCD focuses on repairing the underlying damage all while providing the body with nourishing, easy to digest foods.
Dr. Sydney Haas and Elaine Gottschall
The Specific Carbohydrate Diet is the work of Drs. Sidney and Merrill Haas. In 1951, the Drs. Hass published a book called Management of Celiac Disease that discussed the hundreds of cases of Celiac Disease and Cystic Fibrosis they had treated with dietary intervention. Their dietary approach focused on eliminating specific types of sugars and starches. When patients adhered to their Specific Carbohydrate Diet for one year, they were often able to return to a normal diet without a relapse of symptoms.
Elaine Gottschall entered the picture after her eight year old daughter was diagnosed with ulcerative colitis. She took her daughter to see Dr. Haas who prescribed SCD. After two years of SCD, she was symptom free and able to return to a normal diet. She remained in good health for the following 20 years. Elaine Gottschall wrote a book called Breaking the Vicious Cycle in an effort to create a user-friendly guide to implementing SCD. Most of the information we have regarding SCD originates from her book. I’d highly recommend purchasing a copy if you intend to try SCD.
GAPS vs. SCD
The Gut and Psychology Syndrome (GAPS) diet, designed by Dr. Natasha Campbell-McBride is a spinoff of SCD. It’s used to treat Autism, Dyspraxia, ADD/ADHD, Dyslexia, Depression, and Schizophrenia. The diet differs from SCD in that it introduces foods in phases and adds more probiotic rich foods to recolonize the gut.3 GAPS focuses on brain health over gut health and encourages users to identify foods
they may be sensitive to through a process of elimination/reintroduction. GAPS is more restrictive than SCD and the supporting scientific evidence is rather limited. However, some patients see tremendous results. Please read Dr. Krumbeck’s article: What to do when the GAPS diet fails for more information regarding the GAPS diet and what to do when GAPS no longer works.
Who is the Specific Carbohydrate Diet for?
The Specific Carbohydrate Diet (SCD) is used to treat conditions such as Crohn’s disease, ulcerative colitis, diverticulitis, celiac disease, cystic fibrosis, autism, SIBO, and chronic diarrhea. SCD can also work for patients with mental health symptoms who also have dysbiosis, like patients with ADHD, depression or anxiety and IBS, SIBO or SIFO. It seems that many patients who have overlapping mental health and intestinal health symptoms are good candidates for SCD.
What is the Specific Carbohydrate Diet?
The diet eliminates specific types of carbohydrates including grains, liquid dairy, starches and thickeners, gums, refined sugars and most artificial sweeteners. The carbohydrates that are allowed are single sugars like those found in fruit, honey, homemade yogurt, and certain vegetables (winter squash, bananas, carrots, etc.).1 The foods that are allowed are called “legal” foods while those that are eliminated are called “illegal”. There is no limit to the quantity of legal foods consumed.
As discussed in previous articles, I tend to avoid use labels like “legal” and “illegal” when discussing foods with kids. See more in this article: The fine line between elimination diets and eating disorders. Moving forward I will use “Okay” and “Not Okay” foods for this purpose.
Remember that SCD in most cases is meant to be a temporary elimination diet designed to permanently restore the microbiome. Some children, like those with Inflammatory Bowel Disease, may need to be on SCD long-term, but the goal is always to return to a diet with the least restrictions necessary to achieve our goal.
What are Okay foods and Not Okay foods on the Specific Carbohydrate Diet?
The Specific Carbohydrate Diet (SCD) allows various foods that are generally simple in structure and easy for the gut to digest. Here’s a list of some of the main categories of legal foods on the SCD:
- Fruits: Most fresh, ripe, unprocessed fruits are allowed. Dried fruits without added sugar are also permissible. However, it’s important to note that some fruits may need to be avoided during the initial stages of the diet or if they cause symptoms.
- Vegetables: Most non-starchy, fresh vegetables are allowed. Certain starchy vegetables like potatoes, sweet potatoes, parsnips, corn and plantains are not permitted. Canned vegetables are typically not allowed due to added preservatives and sugars.
- Meats: Most unprocessed meats are allowed, including beef, pork, chicken, turkey, and fish. Processed meats, like sausages and deli meats that may contain additives, sugars, and fillers, are not permitted.
- Eggs: Eggs are allowed and can be prepared in any manner.
- Dairy: Certain dairy products are allowed, like homemade yogurt fermented for 24 hours, natural cheeses, and butter. Most commercial yogurts, milk, and soft cheeses are not permitted due to their lactose content.
- Nuts and Seeds: Most nuts and nut flours are allowed, provided they are not coated or mixed with prohibited ingredients. Seeds are also generally allowed.
- Legumes: Some legumes are allowed, such as lentils, split peas, and dried beans. However, they must be prepared properly to ensure they are digestible. Legumes are often reserved for late-stage SCD, and are often not allowed in early stages.
- Fats and Oils: Unrefined oils like olive oil, coconut oil, and animal fats are allowed. Trans fats and some vegetable oils are not recommended.
- Sweeteners: Honey is the primary sweetener allowed on the SCD. Artificial sweeteners and other natural sweeteners like sugar, maple syrup, and agave are not permitted.
- Beverages: Water, weak tea, and freshly prepared juices from allowed fruits and vegetables are generally permissible. Coffee is also allowed for most people, but it may need to be avoided if it causes symptoms.
- Herbs and Spices: Most non-mixed herbs and spices are allowed, but it’s important to check for added ingredients that might not be compliant with the diet.
- Homemade Foods: Homemade foods that use legal ingredients, like SCD bread made from nut flour, are allowed. Commercially prepared foods often contain illegal ingredients and should be avoided.
Remember, individual tolerances can vary, and some people may need to modify the diet based on their reactions to certain foods.
“Not Okay” foods include:
The Specific Carbohydrate Diet (SCD) restricts certain types of carbohydrates, particularly those that are complex or difficult to digest. Here’s a list of some of the main categories of foods that are considered illegal or not allowed on the SCD:
- Grains: All grains are prohibited. This includes wheat, barley, rye, oats, corn, rice, and any products made from them such as bread, pasta, cereal, and baked goods.
- Starchy Vegetables: Certain starchy vegetables like potatoes, yams, and sweet potatoes are not allowed.
- Canned Vegetables: Most canned vegetables are prohibited due to added sugars and preservatives.
- Processed Meats: Meats that have been processed with additives, fillers, or sugars are not allowed. This includes most sausages, hot dogs, and deli meats.
- Most Dairy Products: Lactose-containing dairy products are not allowed. This includes most commercial yogurts, milk, and soft cheeses. However, specific exceptions like homemade yogurt fermented for 24 hours and certain natural cheeses are permitted.
- Certain Legumes: Some legumes, particularly those that are more difficult to digest, are not allowed. This includes chickpeas, soybeans, and soy products, among others.
- Certain Nuts: Some nuts and nut products, especially those that are roasted or processed with added ingredients, might be prohibited.
- Sugars and Sweeteners: Most sugars and sweeteners are not allowed, including sucrose (table sugar), lactose, maltose, maple syrup, molasses, and artificial sweeteners.
- Commercial Condiments and Sauces: Many of these contain sugars, starches, or other non-SCD-compliant ingredients.
- Canned or Processed Fruits: Canned fruits, fruit juices, and processed fruit products often contain added sugars and preservatives and are not allowed.
- Alcoholic Beverages: Most alcoholic beverages are prohibited, especially those containing sugars and grains.
- Certain Beverages: Soft drinks, commercially prepared juices, and other beverages with added sugars or artificial ingredients are not allowed.
Need more information about SCD?
If you have more questions and want to work one-on-one please check out my website: KaylaLayneNutrition.com. I’d love to meet you.
Are you interested in learning more about SCD? Come join my SCD Course!
- Gottschall, E. Breaking the Vicious Cycle: Intestinal Health Through Diet. The Kirkton Press. 2014.
- Pecanbread.com. The Best Method for Healing with SCD. 2022.
- Campbell-McBride, N. Gapsdiet.com. Rediscover Health. 2022.
Resources for the Specific Carbohydrate Diet:
Informational books and websites for the Specific Carbohydrate Diet
Cookbooks for the Specific Carbohydrate Diet
Eat Well Feel Well by Kendall Conrad
Every Last Bite by Carmen Sturdy’s (also a blog)
Websites for recipe inspiration:
● The SCD Specific Carbohydrate Diet Podcast with Lee Bernstien