THE SPECIFIC CARBOHYDRATE DIET (SCD) IN IBD

What is the Specific Carbohydrate Diet?

The Specific Carbohydrate Diet^TM  (SCD) was developed in the 1920s to treat celiac disease before gluten was found to be the cause. Later, the SCD was popularized by the book, "Breaking the Vicious Cycle," and used for a variety of different conditions, including inflammatory bowel disease, irritable bowel syndrome, celiac disease, and autism. 

How does the SCD work?

The diet is based on the idea that some carbohydrates can fuel the growth of bacteria and yeast in the intestines. As a result, the bacteria and yeast over grow and cause an imbalance in the microbiome. This overgrowth can interfere with enzymes on the intestinal surface and prevent the proper digestion/absorption of carbohydrates. Meanwhile, the undigested carbohydrates fuel more bacterial and yeast overgrowth, hence, a "vicious cycle" begins.

The SCD also believes that the continuous overgrowth can cause toxins and acids to build up. As a result, the small intestine could be injured and excessive mucus could be produced as a defense mechanism.

What are the rules of the SCD?

In summary, the SCD restricts grains, processed sugars, and lactose. However, there are more specific foods that are allowed and prohibited on the diet. See the lists below for examples.

"Legal Foods" on the SCD include:

• fruits, vegetables and legumes (fresh, frozen, raw, and dried)
• most nuts
• fresh and frozen meats, fish and eggs 
• hard cheese, homemade yogurt, and dry curd cottage cheese
• honey
• most oils
• coffee and tea
• mustard and vinegar

"Illegal Foods" include:

• Canned veggies
• Canned fruits, unless packed in own juices
• All grains, including flours
• Potatoes, yams, parsnips
• Chickpeas, bean sprouts, soybeans, mung beans, fava beans and garbanzo beans
• Seaweed and byproducts, including agar and carageenan
• Processed, canned, breaded, smoked meats/fish
• All milk, buttermilk, commercially prepared yogurt and sour cream, heavy cream, ice cream
• Soy/rice/potato/oat/hemp milk
• Instant tea or coffee, coffee substitutes, beer
• Canola oil, mayonnaise (due to additives), Cornstarch, chocolate or carob,
• Bullion cubes or instant soup bases
• Ketchup
• Products made with refined sugar, sugar substitutes, stevia, pectin, molasses, corn or maple syrup, baking powder
• Medication containing sugar
• All seeds, balsamic vinegar, fructo-oligo saccharides (FOS)

Results on the SCD

While the diet has been popular and effective for some, the research studies are still limited (mostly in Crohn's disease). One study found that almost half of the participants on the SCD had low calories, vitamins, and minerals.

Potential problems to watch out for:

• Folate, thiamine and vitamin B6 deficiency from limiting grains
• Calcium and Vitamin D deficiency from dairy avoidance
• Vitamins C, A, and potassium deficiency are possible as a result of limiting fruits and vegetables
• Weight loss at the beginning and poor weight gain later
• Difficulty following the diet

How to be successful on the SCD

To avoid low nutrients on the SCD, we recommend taking a complete multivitamin (containing vitamins and minerals) daily. Additionally, we have some tips and tricks for healthy weight gain if you lose too much weight on the diet. Most importantly, make sure you work with a dietician to help support you on the diet.