With protein powders, protein bars, and ready–to–drink protein shakes currently flooding both the nutritional supplement and mainstream markets, people are often surprised to learn that many of these products are not the healthy, nourishing snacks they’re promoted to be. In fact, as scientists continue to study the effects of protein processing on nutritional quality, some interesting studies have emerged showing that many of the unnatural proteins formed in the production of modern foods and supplements are likely to be at least mildly toxic.
Scientists have long studied various toxic substances which are known to be formed during the production of protein–containing powders; and though it’s likely that many protein–based toxins still have yet to be discovered, there is enough evidence in the scientific literature to make any rational, thinking person wary of certain so–called “health foods”.
We’ve shown elsewhere, how the alkali–treatment of proteins (including common nutritional supplement ingredients such as soy protein isolate, and calcium caseinate), leads to the production of unnatural cross–linked amino acids like lysinoalanine (LAL). Lysinoalanine has been shown to have many negative effects on digestion and overall metabolism:
Quote from the above study:
The data suggested that LAL, an unnatural amino acid derivative formed during processing of foods, may produce adverse effects on growth, protein digestibility, protein quality and mineral bioavailability and utilization. The antinutritional effects of LAL may be more pronounced in sole–source foods such as infant formulas and formulated liquid diets which have been reported to contain significant amounts (up to 2400 ppm of LAL in the protein) of LAL.
Study Link – Interaction of lysinoalanine with the protein synthesizing apparatus.
Quote from the above study:
These results indicate that LAL is an inhibitor of both prokaryote and eukaryote lysyl–tRNA–synthetase. Furthermore, it is incorporated into protein. Both of these actions can be factors in the nephrotoxicity of this common food contaminant.
So, according to the above studies, processed proteins containing lysinoalanine:
• Inhibit growth
• Inhibit protein synthesis
• Inhibit digestion
• Inhibit mineral absorption
• May harm the kidneys
• And impart anti–nutritional effects
It’s more than a bit ironic then, that lysinoalanine (and many similar toxic “anti–nutrients”) can so commonly be found in the ingredients used by the nutritional supplement industry in an ever–increasing number of protein powders, bars, and drinks.
Decades ago, research into the toxic effects of protein processing centered on ways to create the least toxic infant formulas, or the least toxic enteral feeding formulas for hospital settings. Industrially processed proteins were never thought of as healthy, and the products in which they were used were produced for situations in which even poor nutrition was clearly better than dying of starvation. But, in recent years many of the same (or very similar) protein ingredients have been promoted as dietary staples for health–conscious consumers. Since so many people are currently being misled by flashy advertising and fancy product packaging, it’s important to set the record straight on the potentially harmful effects of some of the proteins found in nutritional powders, drinks, and bars.
The Effects of Processing
In addition to alkali–treatment, toxins like lysinoalanine can also be formed as a result of the high heat processes now commonly used to pasteurize milk. Ultra heat treatment, or ultra high temperature (UHT) and sterilization processes are now able to produce milk and milk–based products (like protein drinks) which require no refrigeration – but the formation of lysinoalanine in such products has been found to be shockingly high.
Quote from the above study:
The LAL contents analysed in raw and pasteurised milk ranged from 4 to 24 and 17 to 69 mg kg−1 crude protein, respectively. Compared to that, UHT–treated milk and sterilised milk showed higher LAL levels up to 186 and 653 mg kg−1 crude protein, respectively.
And if milk itself contains such a high LAL content when high–heat processed, it’s certain that protein drinks will fair much worse. Unlike fresh milk, the (alkali–treated) powders used in the production of protein drinks already contain significant lysinoalanine, even before further heat treatment:
Study Link - Lysinoalanine Content of Formulas for Enteral Nutrition
Quote from the above study:
. . .the preparation of caseinates and the thermal stabilization of the end products are the two steps more favorable for the formation of LAL.
And it’s important to note that lysinoalanine is far from the only toxic product formed by heat and pH treatment of proteins – it’s just one of the most studied:
From: Lysinoalanine in Foods and Antimicrobial Proteins
Heat and alkali treatment of food proteins widely used in food processing results in the formation of crosslinked amino acids such as lysinoalanine, ornithinoalanine, lanthionine, and methyl lanthionine, and concurrent racemization of L–amino acid isomers to D–analogs.
Still Think Your Protein Drink is Healthy?
Although many of the byproducts produced by protein processing have yet to be studied individually, there is clear evidence in the scientific literature that heat–treated protein drinks (the kind very commonly available, from soymilks, to protein–containing sports drinks) impart a cumulatively toxic effect.
The following study showed that both soy and casein protein, when subjected to ultra heat treatment (UHT) caused a significant elevation in LDL cholesterol levels.
Study Link – Ultra heat treatment destroys cholesterol–lowering effect of soy protein.
Quote from the above study:
Unexpectedly, at the end of the study, low–density lipoprotein cholesterol concentrations were significantly increased compared with baseline in all study groups. The magnitude of this increase (17–19%) was similar in all active and placebo study groups. Soy protein supplements previously shown to be effective in reducing serum cholesterol had in this study no such lipid–lowering effect after ultra heat treatment.
A 17% to 19% increase in LDL cholesterol as shown in the above study is an enormous elevation, and represents a major threat to health. The study authors concluded that the altered protein structures resulting from heat treatment were responsible.
Note: In the time since we first wrote about the above study, we’ve heard from quite a few people who were able to tie their high cholesterol levels with their consumption of ready–to–drink protein shakes. Such drinks are currently being promoted by professional athletes in flashy television commercials – which is a good indication that their popularity is sure to increase. But sadly, the negative health–effects of these drinks will probably never be suspected by the all–too–trusting public. As a reader of the Integrated Supplements blog, you, on the other hand, know the truth. Spread the word.
Altered Proteins and Intestinal Bacteria
Unlike native, undenatured proteins (protein which the body recognizes as nutritive), these foreign protein–containing substances are apt to be poorly utilized and absorbed. When such proteins are absorbed into the bloodstream, they’ve been shown to tax liver and kidney function as the body attempts to rid itself of them (an elevation in cholesterol level is sometimes indicative of the body’s response to a toxic threat, which may explain the above–mentioned cholesterol increase in response to UHT–treated proteins).
Any factor which impairs the nutritional quality of a protein will also impair protein absorption. And if proteins aren’t absorbed properly, they don’t simply pass through the body unscathed. Rather, in their journey through our digestive tract, altered proteins are likely to be fermented into various other toxic compounds such as phenols, cresols, indoles, amines and ammonia by the bacteria which inhabit the colon. This is one reason why so many protein supplements (including many of the lower–quality whey protein supplements) often cause gas, bloating, cramping, or an upset stomach – this phenomenon is due to the fermentation of protein by colonic bacteria, and is not simply due to lactose intolerance as some people believe.
Study Link – p–cresol: a toxin revealing many neglected but relevant aspects of uraemic toxicity.
Quote from the above study:
P–Cresol is an end–product of protein breakdown, and an increase of the nutritional protein load in healthy individuals results in enhanced generation and urinary excretion. The serum p–cresol concentration in uraemic patients can be decreased by changing to a low–protein diet. p–Cresol is one of the metabolites of the amino acid tyrosine, and to a certain extent also of phenylalanine, which are converted to 4–hydroxyphenylacetic acid by intestinal bacteria, before being decarboxylated to p–cresol (putrefaction).
The action of intestinal bacteria on proteins (especially overly–processed, altered, and poorly absorbed proteins) may explain why the consumption of certain protein–rich foods (processed meat, for example) has often been implicated in the development of colon cancer:
Study Link – Meat Consumption and Risk of Colorectal Cancer.
Quote from the above study:
Our results demonstrate the potential value of examining long–term meat consumption in assessing cancer risk and strengthen the evidence that prolonged high consumption of red and processed meat may increase the risk of cancer in the distal portion of the large intestine.
But despite the claims of some vegetarians that meats are the sole source of such protein–derived toxins, it seems that any overly processed, extensively heated, or denatured protein is apt to produce significant amounts of toxic byproducts in the intestines. The following study found that heat–treated (thermolyzed) casein, egg white, and soy proteins (the kinds of protein sources commonly found in dietary supplements) all caused a marked increase in the production of protein–derived intestinal toxins.
Quote from the above study:
We found that the thermolysis of casein reduces its digestibility and increases colonic protein fermentation, as assessed by fecal ammonium and urinary phenol, cresol, and indol–3–ol. Thermolysis of two other proteins, soy and egg white protein, also increases colonic protein fermentation with increased fecal ammonia and urinary phenols.
Although the heat–treated proteins didn’t lead to the development of colon cancer in the above study (which actually surprised the researchers), the formation of toxic byproducts was significantly increased in animals who consumed the heat–treated protein supplements.
Studies by other researchers have shown that heat–treated casein does indeed lead to the production of aberrant crypt foci (ACF) – well–known precursors to colon cancer development.
Study Link – Promotion of aberrant crypt foci and cancer in rat colon by thermolyzed protein.
Quote from the above study:
Thermolyzed casein promotes early colonic precursor lesions in a dose–dependent and thermolysis time–dependent manner; thermolyzed casein also promotes colon cancer.
Researchers have also found that feeding mice and rats cooked combinations of casein, sugar, and fat led to the formation of microadenomas in the colon (microadenomas are small tumors, a step closer to colon cancer development than aberrant crypt foci.)
Quote from the above study:
. . .a diet containing 20% of cooked sucrose, or 40% of casein and beef tallow cooked together, promotes the growth of colonic microadenomas in initiated mice and rats, and would appear to contain promoters for colon cancer.
Given the above study, it’s truly frightening to note that one of the most popular ready–to–drink protein shakes in the country right now is a “muscle milkshake” which contains particularly high amounts of casein, sugar, and fat. By law, all such drinks must be “cooked” or pasteurized when they are produced – yet it’s doubtful that the millions of people consuming this drink have the faintest idea that they may be dramatically increasing their risk of colon cancer in the process.
Although the research presented here is just the tip of the iceberg in the field, we can see clearly that the heat and alkali–treated protein ingredients found in nutritional supplements don’t offer much in the way of actual nutrition – and that they very well may be mildly toxic.
Excluding protein ingredients like soy protein isolate, caseinate, and whey protein concentrate, as well as any ready–to–drink protein shakes, from our daily routine is a good first step. But even quality sources of protein from fresh foods may be able to form toxic substances in our body if we don’t take steps to protect ourselves. In the next Integrated Supplements blog article, we’ll take a look at some of the strategies we can employ to neutralize these toxins, and reap the full benefits of a healthy diet, and intelligent supplementation.
Stay Tuned
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Study Finds Heat-Processed Protein Drinks Send "Bad" Cholesterol Skyrocketing
