Low Protein vs High Protein Diets

Low Protein versus High Protein Diets:
Their Effects on the body’s pH levels.

Abstract

It is the argument of this paper that a low protein, low carbohydrate diet is health promoting, while current high protein diets can be injurious to health.

The findings in this paper are drawn from a literature based survey on pH levels – the balance of acid and alkaline within the body – and the contribution that diet may make either to disease or to the promotion of health.

Debates about diet can be confusing, particularly with people’s desire to lose weight. A high protein low carbohydrate diet appears to be the answer. However, research evidence shows that too much protein in the diet can upset the body’s pH and result in latent acidosis. Furthermore, some studies suggest that the acidity caused by proteins, particularly animal proteins can lead to a loss of bone density and a greater tendency to develop osteoporosis. A low protein, low carbohydrate diet on the other hand reduces the imbalance in the pH which is health promoting.

Introduction

This paper is about how a condition known as acidosis, which is affected by the pH levels in the body, can cause ailments such as gout, arthritis, diabetes, and coronary problems. The central thrust of the article is that pH levels depend, to a large extent, on diet, or what one puts in one’s mouth. It is also argued that low protein diets are more beneficial than the current, popular, high protein diets when it comes to correcting the pH balance in the body. This field of study stems, in part, from Louis Pasteur’s statement that it is not microbes that are important in the study of disease, so much as the environment or terrain. What this means is that disease develops as a biological process in the body and the rate at which it develops depends on the state of the internal biological terrain – at the heart of which is pH.

This paper will begin with an explanation of pH, its role, and how it regulates our interstitium (the fluid surrounding the cells in our body). It will then look at how the body buffers acids and what happens when our buffering system malfunctions, including some of the disease processes. Finally there will be a comparison of high and low protein diets, and the concluding argument will be that high protein diets contribute to disease, while low protein diets are health promoting.

The pH Factor

There are factors which are common to all diseases and if you can identify those factors and address them then you are most of the way to a cure. Most experts are agreed that many diseases begin at a cellular level. Cells become polluted and acidic and they live in the terrain of your biology. It makes sense therefore to address malfunctioning here, no matter what is wrong with you. The body is largely made up of water and this water has both acid and alkaline components. The first step in this is to measure the alkaline/acid balance in this terrain because the level of acidity in your body is known to have an effect on health.

An increase in total body acid is known as metabolic acidosis. Stavile (2005) maintains that this is usually the result of two things:
“an inability of the kidneys to excrete the dietary hydrogen (H⁺) load, and an increase in the generation of H⁺ that is due to the addition of H⁺ (lactic acid or ketoacids) or to the loss of bicarbonate (HCO₃^–) due to inappropriate wasting by the kidney or the gastrointestinal tract. The response of the body to an increase in the H⁺ concentration involves several processes. The first and most readily available process is extracellular buffering. The most readily measured extracellular buffer is carbonic acid (H₂CO₃). This buffer is considered an open buffering system because compensatory mechanisms in respiratory carbon dioxide (CO₂) (increase or decrease in ventilation) and renal HCO₃^– (increase or decrease in kidney reclamation of HCO₃^–) serve to maintain equilibrium.” (1)

In layman’s terms there is an imbalance in bodily pH levels. The level of acid in anything is determined by measuring its pH – pH is the potential hydrogen factor. The pH of any fluid is the measure of its hydrogen-ion concentration. The higher the pH reading then the more alkaline and oxygen rich the fluid is – while the lower the pH reading then the more acidic and oxygen depleted the fluid is. The ideal balance of alkaline and acid in the body is 7.4 – slightly more alkaline than acid. If you are ill then it is more than likely that the pH level in your body is unbalanced and you are in a state of what is known as acidosis. Acidosis, simply put, means that the hydrogen ions are increased and the pH and bicarbonate ions are decreased. There are then a greater number of hydrogen ions than can be absorbed by the body’s buffering systems. If the situation is reversed i.e. the bicarbonate ions are increased and the hydrogen ions are decreased then the body is said to be in a state of alkalosis.

The hydrogen ions in a substance are measured on a logarithmic scale from 0-14.
Higher end numbers indicate a substance that is more alkaline while lower ones indicate greater acidity (positively and negatively charged ions) in the bodily fluids, i.e. blood, urine and saliva. Thus a person’s pH level can mirror the state of the blood and thus a good indication of health. The screening of live blood cells reveals how much acid is present in the blood. When acid levels are high the blood cells stick together and this slows their movement while carrying oxygen round the body. The composition of the blood only changes when the pH levels are significantly out of balance. Hospital doctors regard this as symptomatic of old age and the degenerative process, thus the day to day imbalances and how these might be addressed are largely ignored by the traditional medical community. Yet if the pH levels become significantly imbalanced this can lead to mutation in the blood cells.

As the pH of the blood goes more acid, fatty acids which are normally electro-magnetically charged on the negative side switch to positive and automatically are attracted to and begin to stick to the walls of arteries which are electro-magnetically charged on the negative side. (And as science states: opposites attract.) It should start to make sense that a society which over-emphasizes food that could push blood to be more acid will have a high rate of heart disease (2).

Our pH levels are directly related to what we eat. When we eat too much protein, sugary food, and drink fizzy drinks we are upsetting our body’s pH levels. pH refers to potential hydrogen – it is concerned with the acid/alkaline balance in our bodily fluids and to what extent the blood is oxygenated sufficiently to travel round the body at the correct rate. Scientists and doctors are of the opinion that the pH levels in our bodies dictate whether or not we are healthy. A healthy pH level is between 7.4 and 7.6 leaning towards alkaline – anything below this means that our bodily fluids are overly acidic. Medical opinion says that an excess of acidity is at the root of most of the illnesses that are the scourge of our modern day society. Modern diets lack many of the vitamins and minerals our body needs because farming methods have caused an imbalance in the pH levels of the soil in which our food is grown. Your body needs these minerals in order to function properly. Without it pH levels drop and become acidic. The body has to get rid of this acid because it can literally eat away the cells and tissues in your body. To do this the body borrows calcium, magnesium and other minerals from your bones and organs to neutralize the acid and remove it from the body. This can lead to a loss of bone density and conditions such as osteoporosis in women (3).

High acidity causes a strain on the body that can go undetected for a long period and lead to conditions such as:

• Cardiovascular damage, including the constriction of blood vessels and the reduction of oxygen
• Weight gain, obesity and diabetes
• Bladder and kidney conditions, including kidney stones
• Immune deficiency
• Acceleration of free radical damage, possibly contributing to cancerous mutations
• Premature aging
• Weak, brittle bones, hip fractures and bone spurs
• Joint pain, aching muscles and lactic acid build-up
• Low energy and chronic fatigue

The key to restoring the body’s pH balance is to introduce into your lifestyle those things which are said to increase the alkalinity levels in the body. This is not to say that everything has to be totally alkaline, the thing to remember is that you need to achieve a balance – some areas of the body actually need more acid than others. The way this is achieved is through buffering.

Buffering Systems and Buffers

A buffer keeps things where they should be and acts as a protective agent – buffering systems within the body are there to protect cells and tissues against damage, particularly that resulting from an imbalance in the body’s pH levels. Buffering is simply another word for balancing the levels of acid and acidity in the body. Good buffering means that your bodily fluids have a good ionic concentration because this maintains the body’s pH system within its ideal range.
…everything has balance and a perfect range. There are compartments in the body that you could say need “total acidity” in order to function. So for our purposes, we will say that the key is “total buffering” which is a good ionic concentration to maintain a solid pH that stays within an ideal range for the thing being measured (4).

The lungs, kidneys and other organs in the body all work together to act as natural buffering systems in the body and restore the blood’s pH levels. They do this by removing excess acids from the bodily tissues without causing any damage to the living cells (5). Every buffer system has an acid form and a base form. If the body’s pH levels become too acidic or even too alkaline then the body’s cells can become poisoned by their own toxic waste. This means that the body’s base operations are not working as they should.

Biological Buffers

The pH of plasma is maintained at 7.4. However, changes in plasma pH may reflect changes in other areas (6). If the pH level is right then the blood buffer equation is CO₂ + HOH <===> H₂CO₃ <===> H⁺ + HCO₃  Any changes in the concentration of either the CO or HCO ions can result in slight changes in the blood pH even though they are buffered. Oxygen and carbon dioxide work together in the blood because they are both influenced by hydrogen ions and equilibrium principles. When oxygen enters the blood via the lungs it reacts with hemoglobin. This reaction produces excess H⁺ ions which react with HCO₃ to produce H₂CO₃  The carbonic acid decomposes and becomes CO₂  which is diffused out of the blood via the lungs. Strenuous exercise may result in the addition of protons to the blood which means the buffer cannot control the pH by itself and so requires the help of other organs.

Natural Buffers

The body produces its own natural buffers. These buffers are chemicals that resist pH changes. If the pH is too low then one chemical will bind some of the hydrogen ions to raise the pH level – if on the other hand one chemical’s malfunctioning results in too high a pH, then the other chemical donates hydrogen to lower it (7). Proteins are the most important natural buffers in the body. They are intracellular and include hemoglobin. Plasma proteins are also buffers but these are in much smaller amounts than intracellular proteins. Proteins contain basic and acidic groups which act either as hydrogen ion acceptors or donors to help maintain blood pH (8).

Phosphate is part of the body’s buffering systems. Like protein it is intracellular and helps to maintain the blood’s pH balance. The equation for phosphate is H₂PO₄^– : HPO₄₂. Phosphate is also important to the body’s urinary system because it acts as a buffer there. The concentration of phosphate elsewhere in the extracellular system is low. Phosphate is part of the body’s buffering systems and helps to maintain the blood’s pH balance. Phosphate is also important to the body’s urinary system (9). Natural proteins also act as buffers in the blood, because proteins are intracellular.

Bicarbonate is a very important buffer in the blood and usually appears as sodium bicarbonate because sodium is a positive ion in the body’s cells. Its combination with the proton H+ means it can be effective in raising blood pH. A truly effective biological buffer helps to maintain the body’s pH levels in the accepted range of 7.35-7.45. It does this by resisting any changes that would shift the pH levels to either side of that figure (10). Sodium bicarbonate can also be taken to help restore the blood’s pH levels this is because it is a natural substance and works with the buffer in our bodies (11). Some foods act as buffers in that they help to keep the body’s pH levels at the required number – they help to restore and keep balance, they are base forming foods. Some other foods upset the balance and result in excess acid, these are acid forming foods. Base forming foods are largely made up of fruit, vegetables and nuts. Acid forming foods are high protein foods such as meat, poultry, fish and eggs, and nearly all carbohydrates.

The normal pH of the intracellular and interstitial fluids is maintained because acids are removed at the same rate as they are added, rather than by the buffer systems. When the acid balance is raised and becomes abnormal because acid is added faster than it is removed the change in the pH is not is drastic as it might have been in a non-buffer solution.

Buffers are there to help regulate the body’s pH levels, thus a buffer such as bicarbonate helps to minimize pH changes. The hydrogen ion easily reacts to things and this affects cells and molecules that are vital to the proper workings of the physiological process. As we have already seen the proper pH level in the body is slightly alkaline at 7.4. If buffers aren’t working properly then this can effect changes in the pH level. Many experts are agreed that changes of 0.2 units either way can have serious effects on the body’s basic operations. If the pH level of the blood goes below 6.9 or above 7.9 for an extended period of time then this can have serious consequences and death can result.

All of our bodily fluids, whether they are inside or outside cells have buffers which are there to defend the body against pH changes. The most important of these buffers is a mixture of carbon dioxide and bicarbonate anion, CO₂ and HCO₃. Carbon dioxide acts as an acid and donates hydrogen ions when they are needed while bicarbonate is a base which soaks up hydrogen ions when there are too many of them. By and large the blood pH is balanced between bicarbonate and CO₂ (12). An imbalance in either of these chemicals, i.e. too much CO₂ or too little HCO₃ will upset the pH balance and can cause acidosis. If the ratio is reversed and there is too little CO₂ and too much HCO₃ then the pH levels become too alkaline.

One other important factor in chemical buffers is blood plasma because the carbonic acid and hydrogen carbonate ion that it contains helps to buffer the pH. When the bodily fluids become overly acidic we call this metabolic acidosis. Metabolic acidosis is affected by diet but it can also be caused by excess physical exertion, by diabetes, by too little food or by a high fat diet. The body responds to this by an increase in breathing. This helps to reduce the amount of carbon dioxide (CO₂) that is dissolved in the blood and this is the reason why climbing several flights of stairs can cause us to breathe more heavily (13).

These chemical buffers work with the physiological buffers (respiratory and renal systems) to balance the pH. Thus with the respiratory system, the rate and depth of breathing changes to rid the body of excess carbon dioxide. The bicarbonate level is raised by the renal system which also excretes the acid or bases through the urinary system. The renal system is the most effective at balancing input against output; however, it can take days or hours for the process to be completed (14). The job of the buffers is to keep cells stable. The body needs all three mechanisms to keep pH levels stable This cannot be done by one mechanism alone.

The other two biological processes which help maintain the pH levels in the blood are the lungs and the kidneys. The lungs regulate the amount of carbon dioxide in the blood and the kidneys regulate the amount of bicarbonate. When the lungs and respiratory system are in a normal state and there is no respiratory disturbance so that the pH is level and the carbonic acid level is constant the equation is 1.2meq/l or PaCO₂ of 40mmHg (5.3kPa). (PaCO₂ x 0.03) = H₂CO₃ meq/litre (15). The lungs and respiratory system can quickly compensate for changes in the body’s pH levels. It does this by restoring the balance to the required PaC0₂ which is very important to keeping the right pH level to avoid respiratory disturbances. The control of PCO₂ levels means that CO₂ must be either excreted or retained by the lungs. This helps to decrease changes in the pH levels caused by non-respiratory disturbances. Any changes in the pH result in changes in respiratory control. If a respiratory disturbance does occur through exercise or through the holding of breath or secretion of gastric acid then the buffer will diminish the changes caused in the pH levels (16).

A second biological buffer is the kidneys or renal system which controls the volume and make up of extra cellular fluids. It does this by manipulating the fluid to maintain the pH levels at 7.4. However, where the respiratory system can compensate for changes in a matter of minutes the renal system can take days to do this. If excess acid is added to the internal environment this will be excreted by the kidneys but until that action is complete the pH will remain imbalanced. It should also be noted that while the kidneys can correct states of excess acid they cannot correct the imbalance if there is not enough acid. If the pH is low because of acute acidosis in the respiratory system then the kidneys raise the pH level towards normal by excreting acid H₊ + Cl^–, NH₄₊ + Cl^– or 2Na₊ + Cl^– + H₂PO₄. (17). The pH is lower in urine than in the blood entering the kidney, the renal venous blood entering the kidney should have a higher pH than the renal arterial blood. The venous blood then mixes with the circulatory system and raises the pH of the blood in the system to normal. Thus the base, or HCO₃ in the blood rises (18).

Compensation

When a non-respiratory change in the respiratory pH happens then this secondary disturbance in the pH is known as a compensatory change. When compensation happens then the pH balance is not completely restored to normal, the remaining abnormality will be in the same area unless there has been some complication in between. This compensatory response is sometimes referred to as either acidosis or alkalosis depending in what direction the imbalance occurs. Compensatory acidosis can be indistinguishable from primary acidosis but it is not a natural state.

Nutritional Buffers

We can help to raise the body’s buffering capacity by eating mineral rich foods and by taking mineral supplements (19, 20). Many grains and carbohydrates (bread, muffins, cakes, etc.) increase the problem of tissue acidity (21). The body obtains alkaline buffers mainly from fruit and vegetables and from supplements and minerals, but meats and grains result in acidity. When meat, carbohydrates and grains are a major part of a person’s dietary intake, and left unchecked this can lead to metabolic acidosis (22).

When we have a diet that leads to tissue acidity this will eventually lead to painful conditions such as arthritis and other joint and skeletal problems. There has been evidence to suggest that an acid state can lead to severe lower back pain since the 1960’s. It was found that the pH levels in patients’ lumbar discs could be as low as 5.7. The lower the pH a patient had, the more intense the pain and the degeneration of the discs and surrounding tissues (23). Certainly acid pH levels have been found to reduce the mineral density in bones and can promote osteoporosis in men as well as women (24). More recently some evidence has led researchers to believe that an acidic terrain may accelerate age related muscle wasting (25). Apparently aging can promote a generalized low grade metabolic acidosis, partly because as we age the efficiency of buffering systems such as the kidneys declines which compromises the renal system’s ability to help regulate pH levels (26).

When our diet is based mainly around fruit and vegetables then research suggests that we can delay the imbalances in pH levels that occur with age because these foods are noted for their alkalinity. Similarly we can further help ourselves by not smoking because smoking is known to raise the acid levels in the body. If we do this then along with dietary changes and consumption of supplements and omega 3 fatty acid, we stand a greater chance of remaining healthier for longer (27).

Findings from research such as the studies mentioned above has led to a division among many practitioners with regard to which foods are good for us and which are not. This is particularly the case with modern dietary fads such as the Atkins diet because too much high protein has been found to upset the body’s pH levels. While a large part of the medical establishment still remains unconvinced on this there are a significant number of trials and studies which support the view that a low protein, supplemented diet is much healthier for us than the high protein diets that are a common feature of modern western society.

Low Protein versus High Protein Diets

We can all appreciate that protein is essential to having a healthy body – the problem is that we have a tendency to over indulge in protein and eat far too much red meat and rich dairy foods. While a certain amount of protein is not only good for us, but essential, an over indulgence is bad and can contribute to our having the condition of latent acidosis. Too much protein has been found to increase the levels of acidity in the body and thus to upset the pH balance.

A healthy person needs approximately forty to sixty grams of protein a day as this is our normal protein turnover per day.

In severe cases it has been argued that high levels of acidity can lead to bone loss. Wachman and Bernstein have argued that bones are affected because the body draws minerals from the bones as a way of compensating for an excess of acid or alkali levels in the body’s pH (28). Our modern western diet is heavily loaded in favor of acid forming foods such as dairy products, carbohydrates and meat and neglects fruit and vegetables. It is this type of diet that some researchers argue can lead to the loss of calcium and a greater likelihood of developing osteoporosis. One study found that having post menopausal women on a high protein diet take the alkaliser, potassium bicarbonate for two weeks significantly reduced calcium and phosphorous loss (29). Furthermore researchers involved in a longitudinal study of bone loss found that those on a diet that was high in alkaline components helped to preserve bone mass density (30).

One of the reasons that high protein diets contribute to the levels of acidity in the body, some researchers argue, is that animal proteins can upset the auto-immune processes, largely because they are so similar to humans. They maintain that type 1 diabetes and multiple sclerosis are linked to the consumption of cow’s milk. Other conditions such as Alzheimer’s the researchers argue are due to the fact that animal proteins have been found to be linked to the formation of highly reactive free radicals. A diet based primarily on fruit and whole foods on the other hand is likely to reverse these processes.

Most recommendations state that the ideal balance for avoiding excess acid in the system and for promoting health should be around 25% protein (or acidic foods) and seventy five percent fruit and vegetables. It is also recommended that people should drink a significant amount of water, preferably reverse osmosis water for a more alkaline diet. Such a diet would major on most fruits and vegetables, nuts, seeds and olive oil. Vegetable and sunflower oil should be avoided as they increase the amount of acid in the system.

Research has shown that low protein diets such as the Mediterranean diet, which is high in fruit, vegetables, oily fish (omega 3) and olive oil along with low amounts of dairy food and red meats has a significant effect on the life chances of those patients suffering from cardio-vascular disease (31). High protein, high carbohydrate diets on the other hand can cause an imbalance in the body’s pH levels leading to a condition called latent acidosis which has been found to be injurious to health. In some cases where the pH levels are so imbalanced metabolic acidosis can lead to serious illness and death.

Conclusion

This paper looked at the process of excess acidity in the body. It has done this by examining what is meant by pH levels and what the effects are when there is an imbalance in the pH. There has also been an explanation and examination of the body’s natural buffering systems – those things which help to correct any imbalances in the pH, and at nutritional buffers. Medical evidence and the evidence from alternative therapies both tend to suggest that an imbalance either way above certain levels in the pH can be injurious to health.

Finally the paper looked at conflicting views on diet and nutrition. It found that by and large research suggests that high protein low carbohydrate diets may help people to lose weight but can cause unseen damage to the body’s buffering systems through excess acid. Research also suggests that any high protein diet will contribute to the amount of acid in the body and eventually lead to an imbalance in the pH.

Conversely there is strong research evidence to suggest that a diet which is low in protein and high in fruit, vegetables and unsaturated fats is not only health promoting but has been shown to reverse conditions such as heart and circulatory problems. It would seem appropriate therefore that more medical research should be undertaken in this area if people are to recognize the benefits of a low protein diet over a high protein diet.

An Exclusive Article for Members
From THE BRIDGE Newsletter of OIRF
Published Septebmer 15, 2007

© Copyright 2007, Dr. Karim Dhanani, Ontario Canada

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