Food Combining

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Food Combining

Postby catalina1 » Sat Feb 16, 2008 8:18 pm

jeff- hi, its anthony. do you find that there are bad combos of fruits and veggies (such as a potato and fruit) or is there no such problem other than certain combos in each individual?
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Re: fod combining

Postby JeffN » Sun Feb 17, 2008 11:20 am

catalina1 wrote:jeff- hi, its anthony. do you find that there are bad combos of fruits and veggies (such as a potato and fruit) or is there no such problem other than certain combos in each individual?


Hey Anthony,

I hope you are well.

There is no credible scientific evidence to support the theories on food combining. While the proponents often say it is based on physiology, they theory is actually based on a very limited view and misunderstanding of physiology. Even in one of the classic books on the topic "Food Combining Made Easy" the author, Dr Herbert Shelton said he knew of no physiological reason for most of his rules. I beleive his many reason in putting them forth was to help people make improvements on the typical diet they were eating.

In addition, even one of the modern day advocates of it, "Harvey Diamond" who popularized the theory in his Fit For Life books, also said publicly at a NHA conference that he may have over emphasized its importance in the books.

One of the reasons food combining seems to work is because when you follow the rules, you have simplified your diet and made a dramatic change in your diet for the better.

In regard to digestion, overeating and eating too much fat and eating while under great sress are three things that can impair digestion. Also, as you mentioned each individual may find they have certain food tolerances and sensitivities and if so, they should respect them.

I have an old article called The Physiology of Digestion: Is Food Combining Justified" which debunks all the theories on food combining and I am going to update and put on my website sometime soon.

In Health
Jeff Novick, MS, RD
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Confused about food combining

Postby collin » Wed Nov 05, 2008 4:53 pm

Hi Jeff,

What you have written above makes sense, however, information about food combining also appears to make sense, at least at first glance.

e.g. from an article by Herbert Shelton:
http://www.rawfoodexplained.com/digestive-physiology-and-food-combining/protein-starch-combinations.html


Physiologically, the first steps in the digestion of starches and proteins take place in opposite media—starch requiring an alkaline medium, protein requiring an acid medium in which to digest. The enzyme ptyalin (salivary amylase) that initiates starch digestion is active in an alkaline medium only and is destroyed by a mild acid. On the other hand, pepsin, the enzyme that initiates protein digestion is active only in an acid medium. If starches and proteins are eaten together, the acid gastric juice destroys the ptyalin and puts an end to salivary digestion of starch. That the presence of the undigested starch in the stomach interferes with the digestion of protein is shown by the presence of undigested protein in the stools. Physiologists have shown that undigested starch absorbs pepsin and this will surely interfere with digestion of protein.



The claim is that digestion of starchy foods interferes with the digestion of higher protein foods due to the alkaline vs acid mediums required.

If food combining rules are not valid, I am wondering how this is explained? I tried searching the web for your article, but did not find it.

Thank you for any insight into this.

- Collin
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Re: Confused about food combining

Postby JeffN » Sun Nov 09, 2008 10:48 am

collin wrote:Hi Jeff,

What you have written above makes sense, however, information about food combining also appears to make sense, at least at first glance.

e.g. from an article by Herbert Shelton:
http://www.rawfoodexplained.com/digestive-physiology-and-food-combining/protein-starch-combinations.html


Physiologically, the first steps in the digestion of starches and proteins take place in opposite media—starch requiring an alkaline medium, protein requiring an acid medium in which to digest. The enzyme ptyalin (salivary amylase) that initiates starch digestion is active in an alkaline medium only and is destroyed by a mild acid. On the other hand, pepsin, the enzyme that initiates protein digestion is active only in an acid medium. If starches and proteins are eaten together, the acid gastric juice destroys the ptyalin and puts an end to salivary digestion of starch. That the presence of the undigested starch in the stomach interferes with the digestion of protein is shown by the presence of undigested protein in the stools. Physiologists have shown that undigested starch absorbs pepsin and this will surely interfere with digestion of protein.



The claim is that digestion of starchy foods interferes with the digestion of higher protein foods due to the alkaline vs acid mediums required.

If food combining rules are not valid, I am wondering how this is explained? I tried searching the web for your article, but did not find it.

Thank you for any insight into this.

- Collin


Hi Colin

This is explained because Dr Shelton's comments were not made based on an accurate understanding of physiology and biochemistry.

A small part of digestion takes place in the mouth with chewing and the release of salivary amylase. About 10% of digestion then takes place in the stomach which is mostly "mechanical" digestion. The stomach works like a food mixer where its muscles churns the food into a pulp called chyme. Many chemicals such as digestive hormones, enzymes and gastric juices are released which help to break down food molecules in the chyme into small particles for absorption into the bloodstream.

The small intestine is where the majority of the "chemical" digestion of food takes place and typically takes about 4-5 hours for the food to travel all three sections of the small intestine and this process to take place, This chemical digestion includes the digestion of protein/peptides into amino acids; lipids into fatty acids and glycerol; and carbohydrates into simple sugars like glucose. Digestive juices from the liver and pancreatic juices from the pancreas and their enzymes, as well as other intestinal enzymes all work in an alkaline environment.

Also, as mentioned above, all foods are a combination of protein, carbohydrate and fats. No animal in nature follow food combining nor does any of the longest lived human populations.

What I would challenge you to do, is to find some current information, (not outdated folklore that sounded scientific) whether from textbooks on anatomy, physiology and biochemistry and/or published studies that show and support for the theories of food combining.

In Health
Jeff
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Thank you!

Postby collin » Mon Nov 10, 2008 1:55 pm

Hi Jeff,

Thank you for detailed response. This is the kind of information I was looking for. I had not made my mind up either way as I was aware of two sides to this issue. I just wanted to know which to believe.

Your explanation is helpful and logical. Thanks for clearing this up. It's very much appreciated!


- Collin
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Re: fod combining

Postby ethersprout » Wed Aug 25, 2010 10:15 pm

Hey Jeff,

I was wondering where (or if) on your website I'd be able to find the article you mentioned "The Physiology of Digestion: Is Food Combining Justified." This sounds like a very interesting read.

Thanks in advance!
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Re: fod combining

Postby NikNik » Wed Nov 17, 2010 8:06 pm

ethersprout wrote:Hey Jeff,

I was wondering where (or if) on your website I'd be able to find the article you mentioned "The Physiology of Digestion: Is Food Combining Justified." This sounds like a very interesting read.

Thanks in advance!


I would like to see this as well
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Re: Food Combining

Postby JeffN » Wed Jan 29, 2014 12:20 pm

It has been a few years since these requests have been made, but the issue of Food Combining has come up several times recently and as such, I went to my old files and found the original article. This article was composed from several discussions on message boards and from emails on the topic during April 1997.

Except for cleaning it up a little, mostly in regard to spelling and grammar, I am leaving most all of it as written 17 years ago. Clearly, the references I listed have been update since, but the information in them will be fairly much the same in regard to the physiology and biochemistry of digestion and only further supporting my position.

Hopefully, one day I will update the references and the quotes.

In Health
Jeff

THE PHYSIOLOGY AND BIOCHEMISTRY OF DIGESTION: Is Food Combining Justified?
© Jeff Novick, MS, RD, LD
April 1997

In recent years the American Natural Hygiene Society (ANHS), now known as the National Health Association, has liberalized its stand on food combining. Their present position states that it can be an effective means to prevent overeating. At the 1998 ANHS conference Dr Joel Fuhrman said that it was not important and wouldn’t add a year to your life. Harvey Diamond relaxed his stand and said that it may work for some people but not for everyone. Yet, amongst the natural hygienists and raw food communities, it is still adamantly promoted and followed. Well, does food combining work? Is it scientifically valid? And why or why not? Lets find out.

The basic principles of physiology and biochemistry of digestion that Shelton (and others) based their "rules" of food combining on were based on an incorrect and limited understanding of human physiology and biochemistry. I will just give a general overview of why that is so.

To begin with, lets look at the process of digestion and in doing so, lets look at it in relation to the four main areas that digestion takes place, the mouth, the stomach, the small intestine and the large intestine.

In the mouth the primary digestion that takes place is mechanical through the teeth, tongue and the chewing of our food. Besides the mechanical breakdown from chewing, the only real biochemical digestion is from salivary amylase, which is secreted by the salivary glands. It is a precursor and a preparatory step for the real starch digestion that happens later. And it works best in an alkaline environment. It is not where much starch digestion really takes place. The amylase works just to break down some larger starch molecules into smaller ones by breaking the bonds in the chains of the starch. Additionally, there is some lingual lipase that is released, mostly in infants (due to the high fat content of breast milk), but it does little to digest the fats we may eat.

The stomach is set up mainly to begin protein digestion by breaking the larger proteins into smaller ones and it does so in an acidic environment, though nowhere near as acidic as a carnivores. This is not the major site of protein digestion. The stomach however, is made up of a very strong musculature and also changes the mass of food that we swallowed from a bolus of food into something called chyme through the powerful churning and contractions and mixture with fluids. There is no other chemical breakdown that is either designed to happen or supposed to happen. Not for fats or for starches. No enzymes for the digestion of fat and/or carbohydrates are released. The system however, is designed to hold both fats and CHO’s in limbo while they get churned up and await their real digestion. And if we are eating normally and rationally, this will happen pretty quickly without the fermentation that the proponents of food combining say is supposed to be so rampant but no one seems to be able to document.

This chyme is then released (~ 5 ml at a time, about 1 tsp) into the first part of the small intestine where the acid is immediately neutralized and changed to a slightly alkaline environment again. Additionally, bile is released to act as an emulsifier for the fat molecules. This is also where the chemicals and enzymes for the major digestion of fats, starches and proteins happen, all together. It’s truly an amazing event. Many specific types of enzymes are released that act on specific substances and it all happens together in this alkaline environment. This is where the real complexity and wizardry of the process really happens. The other areas where just preparatory stages for this part. This is where most of the digestion really happens and it all happens together, fat, protein and starch and all in the same environment, which is slightly alkaline. Even for the protein!

Now, there are a few things that can really mess up or negatively influence this system that we know about for sure. One is a large amount of fats. It will slow the whole process down because the digestion of fat is very difficult, complicated and takes a long time. So there are actual chemicals released (CCK) that signal the system to slow down so it can have the time to work on the fat. It can take up to 4 hours or more.

Drinking with meals can also interfere somewhat depending on the fluid and its temperature, osmolality, etc.,

Stress and anxiety can and will shut the whole thing down. And cause a decrease of the secretions and blood flow that is necessary.

And another one and maybe THE big one... you guessed it, ****overeating*****!! Messes up everything including timing, chemicals, coordination, etc., etc., and it causes distention and problems in the whole process especially in the stomach .

So, why does food combining seem to work so well for those who espouse it? Probably because when practicing food combining they also usually stop overeating (relatively speaking), cut down on the fats, stop drinking with meals, and eat simpler meals all of which have been shown to be helpful. It is also much easier to overeat on cooked, processed, refined, foods then on whole natural raw foods.

So, a lot of what Shelton (and others) said may be accurate somewhat in theory, but it may not actually hold water for the reasons he gave. Starch and protein where never meant to be digested together in the stomach and the system is set up to take care of that as there are some natural foods that do contain both and sometimes in significant concentrated amounts. Or were they a flaw in nature?

Food combining, (from my understanding of it, and my conversations with many of the Natural Hygiene professionals who have come before us) was originally designed and set up NOT for the true practicing Natural Hygienist (who wouldn’t really need it anymore due to the simplicity of their diet), but for the person in transition who was still eating all the "other" stuff, to help ease and simplify their dietary practices and meals and too reduce their dietary atrocities. That’s why except for his little book on it, which if you check out the recipes, aren’t very hygienic to begin with, he never really promoted it. It’s everyone else who has. What role does food combining really play when we are already eating mostly simple healthy meals anyway! :)

The info someone also just posted about achloridosis in humans has been coming to light more and more lately. Especially in the elderly though many middle age adults are also showing it. Seems we have stomachs that aren't doing what they are supposed to be doing in the area of digestion. My guess (and this is a guess) is because of the years and years of overstressing the system with highly concentrated proteins, which overworks and overstresses the acid mechanisms and components. Overuse becomes wear and tear that leads to breakdown and deficiency.

Also remember, (still my theory here) :), another problem is that we go from a conventional diet to a raw food or healthy diet and we haven’t give our system a chance to adjust. It takes a while for certain enzymes to build up their levels (if they still can) to the change. You are talking going from about 11 grams of fiber a day to about 40-60!! Holy Gas and cramping, Batman!!

So, to really improve your digestion without worrying about food combining, just make sure it is whole, natural and unprocessed food, keeping variety simple, chew your food really well, eat slowly, enjoy your food, and most of all RELAX, RELAX, RELAX!!

To me it seems like most of us just use food combining to complicate our lives and to see how far we can go and with what we can get away with in the area of dietary entertainment and complexity.

Keep it simple, relax, and enjoy your food.

In Health
Jeff


Question: You mentioned that for SOME of Herbert Shelton's food combining rules that he knew of no physiological backing. I am interested to know which of the rules this might be.

In Herbert Shelton’s "classic" book on nutrition, "The Science and Fine Art Of Food and Nutrition" (The Hygienic System: Vol II, 1935) in the chapter on Correct Food Combining,

P.317 STARCH- STARCH Combination

"It may be true that the starch splitting enzymes manifest a preference for one starchy food, although I have been unable to find any physiological ground for the statement...”

P. 318 TAKE MELONS ALONE

"I know of no physiological reason for this rule."

Question: ; You said, "the basic principles of physiology and biochemistry of digestion that Shelton (and others) based their "rules" of food combining on were based on an incorrect and limited understanding of human physiology and biochemistry." I would be quite interested in the studies/sources/references. Can you provide me enough info that I could explore the issue independently?

In response to your request on references/citations on food combining and digestion, I will give you just a few of my references and some quotes to get you going.

To begin with, any good advanced level (or medical) textbook on nutrition, biochemistry, physiology and/or anatomy will serve your purpose quite well. And point you in the right direction.

Some of them that I like include:

Grof JL, Gropper SS, and Hunt SM.. Advanced nutrition and human metabolism. (2nd ed). Minneapolis: West Publishing Company. 1995.

Guyton AC. Textbook of medical physiology. (8th or 9th ed). Philadelphia: Saunders. 1991.

Guyton AC. Anatomy and physiology. Philadelphia: Saunders, 1985

Ganong WF. Review of medical physiology. (16th ed). Norwlak: Appleton and Lange. 1993.

More specifically on just digestion:

Johnsohn LR, et al., eds. Physiology of the gastrointestinal tract. 2nd ed. Vols I & II. New York: Raven Press. 1987.

Walsh JH. Gastri Secretion. in: Green M. The role of the gastrointestinal tract in nutrient delivery. New York: Academic Press, 1984,3: 107-118.

Some quotes from the above references…

"Moreover, certain foods and/or food related substances appear to increase the relaxation of the lower esophageal sphincter.... manifested as heartburn... including smoking, chocolate, high-fat foods, alcohol, and carminatives like peppermint"

"another enzyme present in the gastric juice is alpha-amylase that originated from the salivary glands in the mouth. This activity retains some activity in the stomach until it is inactivated by the low pH of gastric juice."

"very little chemical digestion of nutrients occurs in the stomach for the initiation of protein hydrolysis by the protease pepsin" [JN - this only breaks down large protein molecule into slightly smaller peptides]

"most protein digestion takes place in the duodenum, however, and the contribution of the stomach to the total process is small." [JN-very small]

"normally 92-97% of the mixed American diet is digested and absorbed." [JN- and that is on a typical cooked food, poorly combined, high in fat, sugar, salt, irritants, high in animal foods, refined and processed]

"when eaten alone [food] leave the stomach [quicker]. In a mixed diet, emptying of the stomach is prolonged. Liquids empty more quickly then solids, large particles more slowly then small, & hypertonic foods or liquids more slowly then isotonic" [JN - so simple meals, chewed well]

"When protein foods are in the stomach, the pH of the gastric contents actually rises (JN - becoming less acidic) because proteins act as buffers to tie up H+. .... As protein is digested, the gastric contents gradually become more acidic... "

"CHO digestion continues in the stomach until the gastric contents become more acidic." [JN - in spite of the supposed "bad' combo]

"If the digestible CHO remained in the stomach long enough, the acid hydrolysis could reduce most of it to the monosaccharide stage. However the stomach usually empties itself before significant digestion takes place and CHO digestion takes place almost entirely in the small :crybaby: intestine, with the greatest activity in the duodenum." [JN - so the protein enzymes would actually help to digest the CHO, not interfere with its digestion]

"The major portion of fat digestion takes place in the small intestine." [JN - over 95%]

"Normally there is very little bacterial action in the stomach because the hydrochloric acid acts as a germicidal agent... Bacterial action is most predominant in the large intestine. Colonic bacteria contribute to the formation of gases, acids and various toxic substances, many of which contribute to the odor of the feces. The ingestion of CHO in general leads to increased fermentation in the large intestine; protein yields increased putrification. If faulty absorption in the small intestine allows large amounts of protein or CHO to reach the large intestine, bacterial action may lead to the formation of excessive gas and also of toxic substances."

"Emotional upsets, fear, anxiety, or other states that trigger the flight-or fight response, inhibit gastric [and pancreatic] secretions." [JN – Stress is an important factor]

"the only stomach function essential to life is secretion of intrinsic factor. If B12 is administered by injected, individuals can survive ... even after total gastrectomy."

"Pancreatic juice contains sodium bicarbonate which is basic or alkaline in contrast to the stomachs acid. The pancreatic juice neutralizes the acidic chyme as it leaves the stomach to enter the small intestine. From this point on, the chyme remains at the neutral or slightly alkaline pH at which ALL the enzymes of both the pancreas and intestine work best." [JN - this is where the majority of all digestion takes place, all in the same slightly alkaline environment, and all at once.]

"Receptors of the duodenum bulb are sensitive to osmolarity of the chyme, volume of the chyme present in the duodenum, and presence of acid and/or irritants in the small intestine. Gastric emptying is also partially effected by the macronutrient composition of the food. CHO and PRO appears to empty at approximately the same rate from the stomach, fat, however slows gastric emptying into the duodenum, as do many free amino acids. Complex CHO, especially insoluble fiber, decrease the rate of gastric emptying."

"The individuals particular emotional make-up and his manner of dealing with life’s day to day problems and challenges will often be reflected in the functions of his digestive tract.... It is not what he eats; it’s what is eating him that is important. Surrounding every stomach there is a person."

"The best advice is eat less at a sitting, eat slowly, chew food more thoroughly, and relax while eating."


As I said in my original post....

The basic principles of physiology and biochemistry of digestion that Shelton (and others) based their "rules" of food combining on were based on an incorrect and limited understanding of human physiology and biochemistry.

So, to really improve your digestion without worrying about food combining, just make sure your diet is based on minimally processed plants, keep variety simple, chew your food really well, eat slowly, enjoy your food, and most of all RELAX, RELAX, RELAX!!

Much simpler this way! :)

In Health
Jeff
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