The Specific Carbohydrate Diet (SCD)

Until 1924, nearly one out of three children with celiac disease died. That year, Dr. Sydney V. Haus developed a diet known as the Banana Diet (or Banana SCD), where patients were prescribed a whole lot of bananas every day.

During World War II, food shortages caused dietary restrictions, which led Dr. Haas to observe a significant improvement of his celiac patients during bread shortages. He built the first real SCD Diet around the banana SCD diet and his research into his patient reactions to gluten, although throughout his life Dr. Haas was strongly skeptical of research that blamed gluten itself, thinking it was more of an indicator for many of the foods that cause digestive stress. He also identified negative effects from gluten on irritable bowel syndrome and Crohn’s disease.

The modern SCD diet was popularized in 1987, through the book Breaking the Vicious Cycle, by Elaine Gottschall, the mother of one of Haas’s patients. In Breaking the Vicious Cycle, the full scope of conditions that SCD treated was expanded from celiac disease to IBS, Crohn’s disease, ulcerative colitis, diverticulitis, cystic fibrosis, chronic diarrhea, bacterial infections, ADHD, and autism.

The rapid increase in IBD and IBS cases in recent decades, the last century, and perhaps even recorded history, strongly imply that an environmental trigger, such as diet, reacting with particular genetic traits is responsible through changes in gut flora and increased intestinal permeability.1

What is the Specific Carbohydrate Diet?

The specific carbohydrate diet is a restrictive diet. As with many diets significant to IBS and IBD, it is a more restrictive diet that falls under the umbrella of the paleolithic diet family, and is not only gluten free, but zero grain. On paleo diets, we return to a diet similar to the diets that our ancestors have been digesting for hundreds of millions of years. Paleo removes man-made foods such as bread and more recent compounds and toxins that are packaged with modern food, often literally added during packaging. Many recent maladies can be traced to these recent changes in diet, which the bacteria that populate our digestive system are not yet equipped to deal with.

SCD is also similar to the more recent GAPS diet (gut and psychology syndrome), used to treat mental disorders which SCD is also thought to treat, such as autism and ADD, as well as depression, schizophrenia, OCD, and even epilepsy. Another related diet is the AIP diet (autoimmune protocol) which is used to reduce intestinal inflammation to treat autoimmune disorders.

As the name implies, the SCD diet limits complex carbohydrates, disaccharides and polysaccharides. SCD allowances and restrictions are based on the molecular structure of the carbohydrates they contain. Complex carbs with more than one molecule, such as disaccharides (double) and polysaccharides (multiple) are more difficult for the body to absorb. Monosaccharides (single) are more easily absorbed, which is why some fruits and vegetables are allowed and others are not, often for no easily discernible reason.

Many complex carbs are not properly broken down by the body, and that’s fine in moderation, however the influx of increasingly unusual foods we ingest daily, like glitter coffee, can overload those microbes found at the end of our distal intestine and ferment an unusual amount of hydrogen – as well as carbon dioxide and methane – leading to the inflammation of the intestinal wall and common digestive issues such as gas, bloating, and diarrhea. IBS or IBD significantly magnify these symptoms, IBD in particular, because it often results when bad gut bacteria interact with our intestinal immune system.

The SCD diet works by starving out bad or overpopulated bacteria that are unable to efficiently keep up with this increase of foods that are hallmarks of the modern diet – or creepy compounds we put in food that aren’t even food in the first place. This process is not only beneficial to diseases such as Crohn’s, UC, and IBS, but can also be useful for treating bacterial infections, since it starves the infecting bacteria. At the same time, SCD relies on probiotics such as specially prepared SCD yogurt to repopulate our gut flora with bacteria that is friendly to the rest of our digestive tract.

Since we have only been eating those foods for a short time, our guts have not yet had millions of years to adapt to a modern diet. Keep that in perspective when having to spend a few months to a year forcing your gut flora back to the paleolithic age. We have eaten this way before and can eat this way again.

Undertaking the Specific Carbohydrate Diet.

Starting out on SCD progresses in adjustment phases, just like the carnivore diet. But unlike carnivore it begins restrictive and opens up. Once your body adjusts a bit and your population of bad bacteria is starved out and replaced by good bacteria, you can be less restrictive and focus on a solid defense, rather than an aggressive offense.

During this period, you need to be patient. Cheating is not acceptable on the SCD diet, if you want to benefit from eating specific carbs you must adhere completely. In order to do that you have to accept that your body is going through changes and that it may take some time, but you will get there.

If you begin adjusting in a month, that’s amazing, but more likely you won’t see significant results for two or three months, and it can take up to – or more than – a year. At times you could feel like you’re on a rollercoaster, with periodic highs and lows.

Don’t be to deterred, you will probably see basic symptoms begin to dissipate fairly quickly, but the actual healing of your condition and gut itself will take time.

The SCD Diet is restrictive, but if concentrating on self-prepared and organic food is more your style, it could be easier to adhere to than other diets. FODMAP is very restrictive to a large amount of foods that sometimes seem random and that takes time and work to learn. Keto is time consuming and micromanaging in both the foods and quantities you can eat and measure. The carnivore diet is, oddly, the easiest diet to go on, but only if you’re able and willing to eat only meat, salt, and water every day.

After giving your gut bacteria time to rebuild your business, you can begin trying to reintroduce some foods on the illegal list. Remember that even a minor divergence can have huge consequences. After about a year, your guts should be stable enough to let you experiment, but be careful, that doesn’t make you Superman.

Read food labels, but be aware they may be misleading. If a product directly claims to be organic or natural, that isn’t necessarily the truth, even if it’s approved by groups such as the USDA, or other agricultural departments. An official stamp of organic on a label, can mean all kinds of things.

While starting out on the diet, keep a food journal to better identify negative or positive effects and track what you are eating. Ask restaurants to provide exact descriptions of their ingredients. Some foods could have traces of offensive compounds, so be careful eating too much of one thing, that’s bad for your digestion anyway.

Consult with your doctor before making any drastic changes to your diet. They will be able to give you hints about what foods may be more problematic for you, warn you if you should not begin a diet restrictive of a certain food because of personal issues or deficiencies, and track your progress and health as you go along.

A friend of mine recently told me a story about how her son always wanted to go to McDonalds when he was a kid. To him, the McNugget was the holy grail of food, and he could rediscover it like Indiana Jones up to 20 times a trip, 7300 times a year. Eventually, after correctly suspected he was in a suggestible phase, she sat him down to teach him what he was eating. It worked, and after being away from it for only a little while, he couldn’t even stand smelling or looking at it. Cravings go away in absence, because the gut bacteria that program you to have them will go away as well. It might take time, but once you become adjusted to the SCD diet, and improvements to your IBS or IBD, your guts should get along fine.

SCD Food List

On the specific carbohydrate diet, an SCD food list is less necessary than for diets such as the ketogenic and FODMAP diets. SCD follows a more paleo attitude, and removes foods that could be adulterated when processed, or include added sugars, artificial sweeteners, preservatives, and other additives. It’s often just as important to know whether you can eat a type of food, rather than knowing each and every individual food. Like our ancestors, we must use judgement to determine if something is edible, a wheat product, high fructose corn syrup, or – these days – if it’s even food at all. The intention of this list is to provide that general idea, but be sure to consult a full list if you are unsure.2

If you know that a food is safe, then it is safe. The only way to be sure is if you made it at home from fresh, preferably organic, ingredients. A healthy dose of suspicion should be included in the SCD diet, and you should apply that to every label, ingredient, grocer, butcher, friend, and family member – but maybe go easy on your friends and family and make sure they know your specific needs. Even a slight deviation from the specific carbohydrate diet can cause you significant problems.

Meat

SCD Legal
Chicken, turkey, beef, fish, pork, wild game, bacon (cured meats are fine), lamb, and seafood.
SCD Illegal
Processed, smoked, canned, breaded, dried meat, and meat in unknown brine or other solutions. Organic is best.

Vegetables

SCD Legal
Common vegetables, either fresh or frozen. Organic, of course, is best.
SCD Illegal
Any vegetables that have additives, or you are unsure of the content.

Fruits

SCD Legal
Common fruits. Organic, again, is best.
SCD Illegal
Any fruits that have additives, or you are unsure of the content.

Dairy

SCD Legal
Eggs, SCD yogurt – made to the specific carbohydrate diet specifications, aged cheeses, pasteurized and grass-fed butter, and dry curd cottage cheese. Organic, yet again, is best.
SCD Illegal
All milk from animals, margarine, all milk-based products – unless used for making SCD yogurt, and all soft cheeses – except dry curd cottage cheese.

Grains

SCD Legal
None of them. This includes grains that you might think are healthy or are possibly allowed on a more standard gluten-free diet, such as quinoa and brown rice.
SCD Illegal
All of them.

Starches

SCD Legal
None of them.
SCD Illegal
All of them.

Nuts

SCD Legal
All standard nuts, with no additives. Organic, as it always seems to be and always will be, is best.
SCD Illegal
Be wary of commercial roasted or salted nuts, as there may be additional ingredients added.

Seeds

SCD Legal
Seeds are generally okay.
SCD Illegal
Flax, chia, and hemp seeds.

Legumes

SCD Legal
White, lima, black, navy, and green beans, lentils, and split peas. Organic is probably best.
SCD Illegal
Beans in which you are unsure of the cooking process, garbanzo, kidney, fava, pinto and mung beans, bean sprouts, and chick peas, as well as soy beans in any form.

Spices

SCD Legal
Standard single spice products are fine.
SCD Illegal
Mixed spices, spices with anti-caking agents, and spices where you are unsure of the contents. For example, curry powder, garam masala, chili powder, onion powder, and garlic powder should all make you wary.

Sweeteners

SCD Legal
Honey.
SCD Illegal
Everything else.

Drinks

SCD Legal
Drinks overlap with many other categories and share similar legal status. Standard coffee and tea, water, and approved fruit juices are acceptable. Organic, in case you haven’t heard, is best.
SCD Illegal
Instant coffee, some tea, any juices that you cannot be 100% positive of the contents, soda, and milk.

Alcohol

SCD Legal
Dry wine is the easiest, but you may need to check with an attendant, the internet, or a friend who has tried it, because the label or grape is not always forthcoming. Vodka, gin, and the entire whisky family are also acceptable.3
SCD Illegal
Beer, sweet wine, liquors, brandy, and sherry.

Please see our article for more on alcohol and its relation to IBS and IBD.

Sweets

SCD Legal
Unflavored gelatin.
SCD Illegal
No candy. Sorry kids. This list is being posted on Halloween, so I feel moved to mention that for some people, in some cases, honey-based candy could be okay. Try it if you’d like, but try it at your own risk.

Other foods

SCD Legal
Inspect oils closely and tailor them to your own use. Most are allowed, but not recommended, and oils like coconut are particularly bad for IBS and IBD. Homemade dressings, condiments, vinegar, and foods fermented from SCD legal items. Final reminder, organic is best.
SCD Illegal
Unless you know who made it and can confirm that you can eat it, never buy anything at a shop.

In summary, that’s no to “noodle rings,” a 1940’s bundt molded and bundt-sized pasta surprise filled with whatever unholy concoction that could be stuffed in there, but yes to every bizarre jello salad from the latter half of the 20th century, as long as the contents are SCD legal. A jello mold filled with bananas, eggs, and bacon is fine, but leave out the hotdogs, spam, and fava beans. I have no idea if aspic is SCD legal, but do yourself a favor and stay away from it anyway, even if it’s organic.

The SCD Diet and You.

The Specific Carbohydrate Diet is the earliest common modern diet prescribed for digestive disorders. It has seen significant use and observation over nearly 100 years, although it runs into the general problems that any diet encounters with scientific surveys and research into actual effectiveness.

SCD has a longer introductory period than other common diets for digestive relief, so if you are impatient you might want to try something like the FODMAP diet first, or plunge straight into eating meat all the time. Look at your own history and dietary patterns, issues, and adventures, and consult with your doctor or a nutritionist before making up your mind. There are a considerable amount of additional cases and issues that have also found relief from the specific carbohydrate diet, such as mental and bacterial disorders, in addition to IBS, Crohn’s disease, and ulcerative colitis.

  1. See our excellent article about the carnivore diet for more information about intestinal permeability
  2. The website for Breaking the Vicious Cycle, the book that created the modern SCD diet, contains a larger and more specific list of SCD foods. It also provides a great guide to the beginner diet and a recipe for SCD yogurt.
  3. Note on organics: Organic wines have come a long way in the last decade, both in price and quality. You should also look into bio-dynamic and sustainable. Many wine sellers can tell you if a bottle is effectively organic, because sometimes producers simply haven’t gone through the process, or are too stubborn to tweak one minor thing, to receive the organic certification, even if they’ve been making wine that way for a lifetime.