How to Keep the Digestive Juices Flowing

Saturday Mar 28 | BY |
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As discussed in my previous article, it’s very common after a “detox diet” (raw foods, paleo, juice fasting, etc.) to experience extreme reactions after eating “regular” foods.

You eat well for a while that cheating becomes impossible! Some call it the “raw curse.”

Why does this happen? Let’s explore a few reasons why and give some solutions.

Stomach Stretching

The raw food diet, especially the fruit-based version, is a high-volume diet. In fact, the number one problem in newbies trying to make such a diet work is the inability to consume enough calories to sustain themselves during the day. This occurs because fruits and vegetables have a very low caloric density.

The body adapts to the caloric density of a diet by stretching its stomach to allow larger volumes of food to be digested. Author Dr. Doug Graham, who advocates a low-fat, high-fruit, raw vegan diet, recommends going on a sort of “stomach stretching” program to handle the large quantities of food that are required to maintain this diet.

Psychologically, the mind also gets used to very large meals as a routine.

When describing the raw food diet as high-volume, I am not saying that it is worse because more volume is consumed. In fact, the low caloric density of fruits and vegetables is an advantage. Because it is more difficult to get enough calories from fruits and vegetables, it is also more difficult to gain weight on such a diet.

The body will eventually get used to larger volumes of food and fiber. The stomach will stretch. Finally, the mind will adapt, and it will seem normal to eat a salad the size of a beer cooler.

When someone eats a diet like that, it’s very difficult to go back and forth between raw foods and cooked foods.

Therefore, most people binge on huge quantities of cooked foods and can’t understand why they can’t control themselves. This is partly explained by the fact that their bodies have now adapted to a diet low in caloric density.


The body adapts to salt consumption, and it takes a few weeks to do so. Anyone who has gone on a salt-free diet can certainly attest to that. However, because of the physiological adaptations that occur on a salt-free diet, it’s extremely difficult to go back and forth between a diet that contains no added salt and occasional consumption of foods that contain salt (like everything available in every restaurant in the world). The body needs time to adapt to salt intake, just as it needs time to adapt to a salt-free diet.

Digestive Enzymes

The human body is extremely malleable. It reacts to a variety of forces and influences and to their degree of intensity. Eating certain foods makes the body produce certain digestive enzymes to digest those exact foods. That is why someone who goes vegetarian for a long period of time may find it difficult to digest meat if they choose to suddenly reintroduce it.

On a raw food diet, especially one that focuses on fruit, very little digestive effort is required because fruits contain mostly simple sugars with almost no protein, and no starch or fat that require more extensive digestion.

The body will slowly respond to this style of eating by “dumbing down” its digestive powers. “When you don’t use it, you lose it” also applies to digesting complex meals. That is why raw foodists who go back and forth between raw and cooked find they can’t digest meals that they had managed to digest perfectly just a few months before!

The Problems

Even the strictest raw foodists that I know sometimes have to eat cooked food. It could be that they are traveling and options are limited. It could also be that they’re just unable to realistically maintain a 100% raw food diet.

Achieving balance in your diet and your health should not be an all- or-nothing proposition, as many gurus would like you to believe. You should be able to occasionally make some exception to your normal program without throwing yourself completely off balance and sending your body into a feverish state of shock.

Being that sensitive is not a good thing.

Let’s say you’re traveling. One of the greatest joys of traveling abroad is experiencing new cultures. And a huge part of culture is the food people eat. I find it completely unsatisfying to travel all the way to a foreign land and not get to experience some of the food there.

Additionally, when traveling, options are generally limited. You may not find the exact same foods you find at home, so maintaining any kind of strict diet (raw foods, vegan, etc.) is a challenge. Having the possibility of making an exception once in a while is part of a normal and healthy life balance.

Some raw foodists have taken the concept of purity to such an extreme that they’re making their bodies constantly more sensitive and their digestion extremely delicate. They start off as raw foodists, but then refine their program by eliminating all complicated recipes and eating only fruits, vegetables, nuts and seeds.

Then they eat less than 10% fat. But as their digestion weakens, they find that they feel even better when they only consume fats from avocados, and they start avoiding nuts. At some point, they feel that even the avocado is bringing their energy levels down, so they eliminate that too, achieving the diet many refer to as 90-5-5 (90% of calories from carbs, 5% from fat, 5% from protein). In this program, the only fat you’re getting (less than 5%) would be contained in fruits and vegetables, all of which contain negligible amounts of fat.

Of course, with each refinement in their diet they feel better, and upon reintroducing newly forbidden foods (like nuts), they feel a “drop in energy.” Essentially, they’re dumbing down their digestion to the point that they can only consume foods that pass right through the system with minimal transformation. There’s no doubt that such a program can increase energy levels, since so little energy is now used to digest food. However, it’s a slippery slope, and this program cannot fulfill nutritional needs in the long term.

Such a person would probably feel like they’d been run over by a bus if they ate something as simple and inoffensive as a tiny bowl of cooked brown rice.

At some point, you feel like the buffet of life has been shrunk to a small table, when all you can eat is truckloads of fruit, and your body can’t handle any other food. It means you can’t eat out with friends for the most part. You probably can’t travel, or only to places that will cater to your needs. And you create a life that is centered around food, since your main worry during the day will be how to meet your caloric needs by eating enough of those fruits and vegetables.

Putting the health and nutritional concerns of such a program aside for a while, it’s quite obvious that strict raw food diets are not for everybody.

Consistency is Key

This key is consistency. It’s very important to get out of the “YO-YO” mentality — always going back and forth between extremes.

An example of the “yo-yo” lifestyle would be to eat 100% raw or pretty close to it, but cheat on the weekends and feel bad about it (and feel physically terrible). Or always try to go on new cleanses, detox programs, and fasts.

You need to find balance. You need to develop a consistent routine and stick to it.

This is why what some people call the 95% raw food diet doesn’t work. It’s better to either stick to a 100% raw food diet — all the time — and in fact stick to a consistent raw food diet, than to go back and forth constantly.

For most people, as we’ve seen, a 100% raw food diet is not appropriate. So what we need to do is to design a plan that incorporates the level of raw foods that you feel comfortable with, as well as the right balance of nutrients, and then stick to it. Eat some cooked food every day. Don’t just occasionally binge at restaurants. Stay consistent, and your digestion will improve, your moods will get better, and you will experience stability.

How to Keep the Digestive Juices Flowing

There are a few things you can eat that will help build your digestive power so that you are not so sensitive anytime you eat something outside of your “normal ideal guidelines.”

Unfortunately, very little scientific research exists on this topic since interest in extreme diets among the scientific community is almost non-existent. Very few people actually follow a 100% raw food diet for decades, and almost no studies have been done on the long-term effects of this diet.

So the following observations are based on my personal experience and that of other raw foodists I have met and interviewed over the years.

If you’ve been following a very restricted diet for an extensive period of time, it’s likely that your body has temporarily lost some digestive “memory” and needs to be patiently retrained in order to operate properly again.

The level of retraining will depend on the level of restriction you’ve imposed on yourself, and for how long you’ve done it. In my first few years as a raw foodist, I did not restrict fat (such as nuts), but I did restrict all condiments. That is why simply going to a raw food restaurant where condiments were used would “make me feel like crap.”

There are essentially a few categories of food — whole macronutrient classes, in fact — that need to be reintroduced carefully in order for digestive juices to flow normally again. They are:

Salt — This one has nothing to do with digestion, but more with how the body regulates sodium intake. Although going salt-free has its benefits, using a little bit of salt on your food will make you able to at least withstand eating out, where salt is used massively.

Protein — This category includes all animal protein, but also concentrated sources of vegetable protein, such as tofu. The inability to digest protein will be noticed when these foods are expelled from the body almost undigested and with an unusual amount of bile in the stools.

Fat — If you’ve eliminated all fats for a while (nuts, oils, avocados, etc.) your body will need some retraining in order to be able to digest those foods again. You can tell your body has lost its ability to digest fats when you feel like you’re about to die after eating a fatty meal.

Cooked starches — The body can also get weakened in ability to digest cooked starches. This manifests itself in unusual tiredness and sleepiness after even a small amount of starch (for example, a cup of rice).

Readjusting to Salt

A very basic thing that can be done to prevent much of the “feel like s**t” feelings when cheating on a rather pure diet is consuming a little salt on a regular basis. The body is expert at adapting to sodium intake. But if it changes dramatically, you can be in trouble.

I do believe that a relatively low-sodium diet can be very healthy, but it’s not very practical in the real world. Lots of foods are simply not that enjoyable to eat without a little salt, and you’re bound to come across added salt in almost any meal eating out.

How much sodium is healthy? Previous recommendations put the upper limit at 2300 mg. a day for most people. Now the ideal limit is 1500 mg. a day. There are, of course, passionate debates within the alternative health community on this very topic.

But even if you wanted to stick to official recommendations, your food already contains 500 mg. of sodium (naturally occurring in fruits, vegetables, grains and other foods), which means you could add an extra 1000 mg. of sodium a day. That’s a little less than half a teaspoon of salt per day. That’s a small amount, but generous enough to not feel completely deprived and enjoy a little salty kick to your food.


Protein stimulate hydrochloric acid production. A low-fat raw food diet is a very low-protein diet; therefore one that stimulates very little production of digestive enzymes and hydrochloric acid. When a raw foodist goes off the wagon with a cooked meal, she’s rarely able to digest it properly because her system is no longer used to digesting more complex substances.

If your goal is to be able to digest a wider variety of foods, you should consider adding some protein foods. The amounts need not be very large, and for animal foods, it’s not necessary to consume them every day.

Keep in mind that some foods, such as nuts and seeds, are considered “protein foods” but are actually sources of fat. A protein food is a food where most of the calories come from protein.

If you’re a former raw foodist who wants to stay vegan, I would suggest adding some tofu and soy-based meat substitutes to your diet for a little while. Even if you’re not planning to eat these foods in the future, it will benefit your digestion and help retrain it to handle a wider variety of foods.


Deficiency is usually not a problem, as most raw foodists tend to eat more of their calories from fat than any other macronutrient. However, it could be a problem for people who try to restrict their fat intake to less than 10% or even 5% of total calories.

There is a new tendency within the raw food movement to go“90-5-5.” People following this diet eat only fruits and vegetables and use no added fats of any kind. No avocados, nuts, seeds or oils.

Because fruits and vegetables seldom contain more than 5% of their calories from either fat or protein, the macronutrient breakdown of the diet is: 90-5-5  (90% carbohydrates, 5% fat and 5% protein).

If you’ve followed such a program for a good period of time, or even just consume fatty foods infrequently, you will have some fat-digesting retraining to do.

Nut butters are probably the best place to start, as they are relatively easy to digest and contain many essential nutrients. Eat 1-2 ounces a day.


Starches are some of the easiest foods for the human body to digest and assimilate. Yet, if you’ve been abstaining from them, you will find it challenging to eat your old comfort foods such as potatoes, rice or beans. The main symptom is a feeling of extreme tiredness after eating even a conservative amount of starch, or a sort of “hungover” feeling the next day.

The good news is that your body can easily be retrained to digest starch. Start with root vegetables, such as potatoes, and then move on to rice and beans. However, make sure you restrict yourself to a small quantity at first. You don’t want to sit down to eat two or three pounds of cooked potatoes and then complain later that these foods are evil because they make you feel so tired!

Practical Uses

Let’s say you currently follow a very pure diet: no added salt, no starch, etc. However, you’re planning a trip where you KNOW that you won’t be able to follow your diet. How can you avoid getting sick?

Prepare a few weeks in advance by training your body. Add a little salt, fats, protein and starches — starting in very small quantities and increasing them gradually. By the time you leave for your trip, you should be able to digest a wide variety of foods and meals without ending up sick with fever and ruining half of your trip!

Frederic Patenaude

Frederic Patenaude has been an important influence in the raw food and natural health movement since he started writing and publishing in 1998, first by being the editor of Just Eat an Apple magazine. He is the author of over 20 books, including The Raw Secrets, the Sunfood Cuisine and Raw Food Controversies. Since 2013 he’s been the Editor-in-Chief of Renegade Health.

Frederic loves to relentlessly debunk nutritional myths. He advocates a low-fat, plant-based diet and has had over 10 years of experience with raw vegan diets. He lives in Montreal, Canada.


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  1. Annnette says:

    Thanks for this very balanced and informative article. I’m 5 years out from breast cancer and when diagnosed, I was put on a raw food diet along with a digestive enzyme or 2 with each meal. I’m now more of a 60-40 raw vegan but am still taking the digestive enzyme with each meal, what are your thoughts on them?

  2. elguard says:

    I suggest tempeh rather than tofu, as unfermented soy is not beneficial, even edamame : )
    See info from Weston Price foundation.

  3. Emily says:

    Brilliant, Fred. I always appreciate your food wisdom. I am an omnivore right now, but this article answers some questions I’ve had and also addresses some issues I’ve observed in friends. Very informative and well-written. Thank you!

  4. Sarah says:

    I used to be on a raw food diet. Now eat ‘normal’ but eat 3x too much so am overweight. Do I go back to raw? How do I slow my appetite. thanks

    • Why not go back to raw but include a part of cooked in your diet? Of course you can’t eat the same quantities of cooked food as raw foods, but you CAN and should include a lot of water-rich foods. Start each meal with a big salad or soup.

  5. MAK says:


    Thank you so much for the article.

    I followed the food combining diet (protiens and carbs n fruit seperated) for a long while.

    After perhaps 2 years or so I tried eating normally again (mixing the various food groups) and use to get almost immediately sick. Flu like symptoms.
    Even just the smallest of cheats would land me up being sick.

    A tried obtaing for reasons for this, but could not get any explanations or answers.

    This article was very beneficial to me. I’m sure there might be many people experiencing the same but have no idea why or how to reverse these flu like symptoms.

    Thank you.

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