In this article, we will find out how the diet works, its pros and cons, who is it recommended for, and exactly which foods are allowed and prohibited on SCD.
What Is the Specific Carbohydrate Diet and How Does It Work?
The SCD is an elimination diet that focuses on eliminating complex carbohydrates from the diet. According to SCD experts, complex carbs seem to boost an overgrowth of unhealthy bacteria and yeast in the small intestine, which causes inflammation and reduces the absorption of nutrients.
Specific Carbohydrate Diet eliminates all carbohydrates with two or more linked sugar molecules (di, oligo, and polysaccharides), yet permits carbs with single, unbound sugar molecules (monosaccharides), as they are easier to digest and absorb. As such, SCD is believed to starve unhealthy bacteria, inhibit their growth, and restore the digestive system.
SCD allows grain-free, sugar-free, starch-free, and unprocessed foods, and as such, it is very nourishing, natural, easy to digest, and similar to what our ancestors used to eat. It eliminates many man-made ingredients, which are hard to digest and may cause toxins, acids, and other irritants, and thus allows the gut flora to stabilize and heal.
Gottschall, in her book, suggests starting the diet with an introductory period of 2-5 days by completely eliminating all complex foods and ingesting only a few specific ingredients. Once the gut balance is restored, gradually add other items back to the diet, while still sticking to mostly complex carb-free foods. Some patients may come off the diet once the symptoms completely disappear, while others may need to remain on the diet indefinitely. According to Gottschall, you should remain on the diet for at least a year after all symptoms disappear.
Consider keeping a food journal to monitor what you ate and how it made you feel, which will help you track your progress.
Who Is the SCD Diet Recommended for?

Originally, the diet was developed by Dr. Haas for patients with celiac disease. However, the biochemist Elaine Gottschall soon realized that it is also very effective against ulcerative colitis and thus wrote a book about it.
Since then, SDC has helped numerous people with many kinds of gastrointestinal problems and inflammatory bowel diseases (IBD), including Crohn’s disease, diverticulitis, cystic fibrosis, chronic diarrhea, and several autoimmune diseases. Some people even claim the diet helps with autism-related digestive issues.
Many of these diseases can hinder the body’s ability to digest and absorb nutrients, especially grains, legumes, refined sugar, and high-starch foods, and SCD is said to restore intestinal functions.
SCD is mostly used to treat intestinal disorders, however, data also suggests that it may be effective in combating other medical conditions – especially behavioral and autoimmune disorders, such as cystic fibrosis and autism spectrum disorder (ASD). Nonetheless, this data mostly relies on anecdotal reports instead of scientific research.
SCD Prohibited Foods
SCD prohibits basically all complex carbohydrates, therefore the list of foods to avoid is quite extensive. Some of the main SCD prohibited food groups include:
- Sugar, sucrose, maple syrup, and other processed sugars, artificial sweeteners, as well as food and beverage containing them
- Sweets, such as candy and chocolate that contain FOS (fructooligosaccharides)
- Processed foods and canned goods, including canned and processed meats with additives
- Canned and processed vegetables and fruits due to the common addition of sweeteners and preservatives
- Canola oil and commercial mayonnaise – due to additives
- Dairy products that are high in lactose, including certain types of cheese, milk, commercial yogurt, cream, sour cream, and ice cream.
- All grain, including wheat, wheat germ, barley, millet, corn, oats, rice, quinoa, and others, as well as bread, pasta, and baked goods made with grain-based flour
- Potatoes, sweet potatoes, turnips, yams, and other starchy vegetables
- Most legumes
- Seaweed and seaweed products
- Curry powder and onion/garlic powder with anti-caking agents
- Sweetened beverages, instant coffee, flavored liqueurs, brandy, and sherry
SCD Allowed Foods
Some of SCD allowed foods include:
- Meats without additives – unprocessed poultry, turkey, beef, pork, lamb, wild game, fish, and shellfish
- Eggs
- Some cheese types, such as cheddar, Colby, Swiss, and dry curd cottage cheese, ghee, butter, and homemade yogurt that has been fermented for 24 hours or more
- Some legumes, including lentils, dried navy beans, peas, lima beans are permitted after soaking
- Most fresh, frozen, raw, or cooked vegetables and string beans, including asparagus, beets, broccoli, Brussel sprouts, cabbage, cauliflower, carrots, celery, cucumbers, eggplant, garlic, kale, lettuce, mushrooms, onions, peas, peppers, pumpkin, spinach, squash, string beans, tomatoes, and watercress
- Fresh, frozen, raw, cooked, or dried fruits with no added sugar, including apples, avocados, bananas (ripe with black spots), berries of all kinds, coconut, dates, grapefruit, grapes, kiwi fruit, kumquats, lemons, limes, mangoes, melons, nectarines, oranges, papayas, peaches, pears, pineapples, prunes, raisins, rhubarb, tangerines
- Most nuts and nut flours, including cashews and peanuts (free from added sugar or starch)
- Most oils
- Most non-mixed spices without anti-caking agents
- Tea and coffee (make it weak and unsweetened)
- Mustard
- Cider and white vinegar
- Juices with no additives or sugars
- Honey as a sweetener
- Water, mineral water, dry wine, gin, rye, scotch, bourbon, vodka
Does SCD Work?

One of the main problems with this diet is that it lacks scientific evidence. Most support comes from testimonials and there are only a few small clinical studies that have shown the diet’s effectiveness in managing certain gastrointestinal conditions.
For example, several small studies show promising results in improving symptoms of IBD, especially in children. A 2017 study also shows that the diet may be effective in treating Crohn’s disease in both children and adults. In addition, a 2015 survey of 50 individuals who followed SCD while in remission from IBD, suggests the diet may have some benefits, and an anonymous 2016 survey of 417 people shows that most people with IBD benefit from following the diet. However, self-reported surveys are not considered reliable enough to be accepted as a scientific fact.
Currently, the available data is too limited and weak to determine whether the diet really works for either IBD or any other conditions. To prove SCD effectiveness and safety more research is needed.
If you are wondering whether or not to try the SCD diet, there is no definite answer. A well-planned elimination diet may certainly help you figure out what works for you and ease the symptoms and complications related to long-term medications and surgeries. Nevertheless, keep in mind that there is no guarantee that the diet will work for you. In addition, make sure to know the potential challenges and consult your doctor on how to avoid them.
Precautions
Before you begin with the SCD diet, make sure to talk to your doctor. As a restrictive diet, SCD eliminates many food groups, including whole grains, certain legumes, and most dairy, which can lead to insufficient intake of calories and nutrients. People on the SCD elimination diet often get insufficient amounts of vitamin D, calcium, vitamin B6, folate, and thiamine. This diet also makes it harder to consume enough calories and thus maintain a healthy weight. A doctor or a dietitian will help you come up with a diet that will prevent malnutrition and other issues and give you a balanced, healthy, and complete meal plan.
As the diet limits lots of foods that are often consumed in our culture, it can also be hard to follow. In addition, people who suddenly change their diet drastically must reinvent their weekly menus and at first, it takes them more time to prepare their meals In fact, a study of 50 participants showed that people following the SCD diet spend on average almost 11 hours a week to prepare food.