Are Protein Shakes Bad For You?
Although research hasn’t proven their role in sports performance and muscle strength, the ubiquitous protein shake has become a central presence in the lives of most fitness conscious people today and is the golden boy of the multi-billion dollar supplement industry. Once chalky and foul tasting mixtures of calcium caseinate used almost exclusively by bodybuilders and power-lifters in the 1970’s and 80’s, protein shakes have evolved into slickly advertised and milkshake flavored smoothies sold at trendy shops. Sales of protein shakes and its cousin the protein bar, increase each year as more mainstream members of the public use them as a quick and handy meal replacement. A 2005 study published by the American Academy of Pediatrics even found that protein powders and shakes were the supplements most commonly used by those aged 12 to 18, which isn’t surprising given the advertising that promises muscles from a can. In the fitness world, protein shakes are seen as an indispensable part of achieving a lean, muscular physique and they are sold at just about every gym in the country. Without a doubt, the number of fitness minded people who don’t use protein shakes are few, and I will be first to admit that I used protein shakes religiously for over ten years earlier in my career. This is no longer the case as I don’t use them anymore, nor do I advise any of my personal training clients to use them. Experience has taught me that protein shakes are not that effective for building quality muscle in a drug free athlete, and using them can be an easy way to get fat and adversely affect your health.
Protein can be thought of as the building blocks for our bodies. Muscle, bones, skin and other tissues are all made from protein and everyone needs in varying amounts to stay healthy. The appeal of protein shakes is that most people don’t always have access to wholesome meals and so a ready to drink shake is looked upon as a handy and healthy alternative- but is it really? The past hundred years have been a too often ignored history lesson of what goes wrong when we add unnatural food products to our diet. Cardiovascular disease and diabetes now affect as much as 25% of the U.S. population and blame for the increase lies squarely on the new foods introduced into our diet in the latter half of the twentieth century. Nothing could be more further from a natural human diet than a protein shake or bar and given the fact that there are no safety testing criteria required by the FDA for supplements, we have nothing concrete to vouch for how their long term use will impact our health. The list of fallen ‘healthy foods’ consumed by the fitness minded over the years is an impressive one. Trans fats laden margarine became a staple among the health conscious during the 70’s and 80’s while low fat food products are popular items today. All sold based on nothing more than advertising hype and endorsements while time and science proves them all to be questionable for regular human consumption. It is important for us to realize that over the past 150,000 years of our existence as a species, the human body has evolved along with the very foods that sustained us in a harmonious and mutually beneficial way. Societies labeled as primitive that subsist on only naturally occurring foods do not have the prevalence of metabolic disease.
Protein Shakes Are Unhealthy & Unnatural Food Products
Our bodies are a marvels of biological perfection, and so is the environment in which they evolved. For millennia, we have relied exclusively on natural food sources for our sustenance. Our ancestors ate meat, fish, grains, grasses, nuts, eggs and other foods, but their diets did not include protein shakes with cross filtered, pre-digested whey proteins or micellar casein. The argument that protein shakes are made with natural ingredients are a moot point, as many products made with natural ingredients are harmful to human beings. Potassium cyanide can be harvested from wild almonds, and stating that it has ‘all natural ingredients’ will do little to reduce its toxicity. The most popular protein shakes are made with whey or casein which are both milk derivatives, but although they exist in milk, they do not exist naturally in isolation without the presence of other nutrients- a factor we are learning to be critical in the way the body digests micro and macro nutrients. An excellent example would be vitamin supplements. You can take the most expensive vitamin tablet to ensure your intake of essential vitamins and minerals, but because the many other chemical compounds naturally present in meats, grains, fruit or vegetables are absent, our bodies simply cannot absorb the vitamins as efficiently. Since vitamins were first isolated in the early 20th century by biochemist, Casmir Funk, we have embarked on an unsuccessful quest to reduce foods to simple compounds of vitamins, proteins, carbohydrates and fats with the creation of engineered food products. The failure of the modern food industry to create and sustain an overwhelmingly healthy population should set off an alarm in the heads of anyone serious about taking care of their bodies. It took thousands of years for our bodies and our foods to evolve. There is a very strong relationship between us and the foods responsible for our survival as our bodies have learned over time to extract vital nutrients from these foods, while they in turn evolved to be more appealing to our senses and our taste buds. You don’t need a label with well muscled individuals making outrageous claims to make an apple on a tree appealing, but you need a pretty good public relations campaign to make the idea of liquid proteins palatable to the general public- and that is exactly what modern marketing has done. Liquid proteins can never share the kinship that we have with real foods and it is doubtful that it ever will.
Protein Shakes Can Make You Fat
The protein found in many of today’s shakes are predigested, which means they are chemically altered to allow for faster assimilation. In terms of supplying protein quickly to needy muscles, this sounds like an excellent idea, especially after a hard workout, but it actually isn’t. Many studies confirm that ingestion of protein can increase your metabolic rate over 30% more than other food sources. This increase in metabolic rate from protein intake is called the thermic effect, and is a key factor in effective body fat reduction and is one of the reasons high protein diets are recommended for promoting fat loss. However, by drinking a protein shake in liquid form, it will always be assimilated faster than its natural, real food, solid counterparts. The rapid assimilation will thus significantly decrease the thermic effect. Factor in that these proteins are also partially pre-digested, it becomes obvious that this will further reduce any thermic effect. The rapid ingestion of a high calorie liquid protein can also lead to diarrhea, bloating and have a negative effect on eating behaviors. The skills required to lose weight long term by making consistent healthy real food choices go out the window when a protein shake is used to replace a meal. Let us not forget that a protein shake is still a source of liquid calories, and even the low calorie varieties can add up.
There is growing evidence that our bodies are unable to detect the calories in these new ‘liquid foods’ as when we eat solid foods. Our bodies have evolved so that solid foods make us feel satisfied, fluid calories, like the ones you would get from a protein shake don’t have strong satiety properties, nor does it suppress hunger. In fact when using fluid calories from any source, studies have shown that people often end up eating more calories overall as they ingest calories from the liquid and then keep eating as they are not satisfied by liquids in the same way, which sets the stage for overeating and weight gain. Physiologically the mechanisms behind hunger and thirst are very different. Thirst is quenched when your brain sends a signal that your blood and cell volume has increased, but hunger is regulated by signals from your stomach and intestines. When you eat solid foods, the nerves in your stomach detect that your stomach wall is stretching and sends a satiety signals to your brain while your intestines release hormones that all contribute to you feeling full. Protein shakes are often used on an empty stomach to replace a meal, but as you can see from the way in which our bodies are designed, it can’t satisfy you the way solid foods can and my experience has been that people using protein shakes as meal replacements during the day tend to overeat at night as your body isn’t satisfied by the liquid calories. People using protein shakes as a way to reduce their overall calories for purposes weight loss are only able to do so for limited periods. Over time the urge to eat solid foods (and the wrong ones at that) become overwhelming and any weight lost while using the shakes as a meal replacement tends to be rapidly regained.
As an up and coming natural bodybuilder, one of the first rules I learned from my coaches is that you never have protein shakes before a contest, and that you should always eliminate them at least three months out if you really want to get your body fat levels down. In so doing, you rely solely on solid foods that take full advantage of the thermic effect. My coaches, maintained that long before there were protein shakes, men and women had no problems building muscle and reducing their body fat and it is hard to argue with the list of impressive natural bodybuilders before the 1970’s. They also believed that consumption of protein supplements promotes water retention and increased body fat that many mistake for an increase in muscle mass. Take a look at the average protein drinking gym-goer and chances are that they don’t sport well defined abdominals. Instead they tend to look a bit on the bulky side- a look that can be easily duplicated by drinking milkshakes instead of protein shakes. They are a lot cheaper and at the end of the day, will do the same thing- which is make you fat.
Protein Shakes Are Unregulated & Often Contain Harmful Ingredients
‘Pharmaceutical grade’ is a common element on many protein supplement container, however the truth is that FDA regulations do not require protein drinks to undergo any form of safety testing. That being said, it is no surprise that a recent review by Consumer Reports found that all of the protein shakes tested had at least one sample containing lead, arsenic, cadmium and mercury 
- A sampling of the three recommended daily servings of a popular Myoplex product by EAS found 16.9 micrograms of arsenic (the safety standard set by U.S. Pharmacopeia (USP) is 15 micrograms) and 5.1 micrograms of cadmium- which is just above the USP limit of 5 micrograms a day.
- Muscle Milk samples contained all the heavy metals mentioned: lead, arsenic, cadmium and mercury with the daily recommended serving yielding 5.5 micrograms of cadmium (5 micrograms is the safe limit), 13.5 micrograms of lead (10 micrograms is the USP safe limit), and 12.2 micrograms of arsenic.
These numbers should not be taken lightly, as heavy metals such as cadmium accumulates in the body and can bring about extensive kidney damage.[4,5,6] Heavy metals also have a tendency to stay in the body and it can take as long as 20 years to eliminate just half of the cadmium it absorbs today. The Consumer Reports investigation notes that cadmium raises special concern because it accumulates in and can damage the kidneys, the same organs that can be damaged by excessive protein consumption. And it can take 20 years for the body to eliminate even half the cadmium absorbed today.
Protein Shakes Can Cause Kidney Damage & Possibly Liver Damage
Kidneys be damaged by high levels of heavy metals found in protein shakes. and they may also exacerbate underlying kidney problems. Many routinely drink upwards of the recommended servings of protein shakes throughout the course of a day by adding extra scoops or by having over three servings. The idea that more is better is especially prevalent among those seeking to build muscular physiques and there are no protein supplements with labels spelling out what the maximum serving sizes should be, that of course would be bad for business. Anyone with diabetes or kidney problems could find themselves facing serious side effects from overdoing their protein intake and shakes make it all the easier to do so. People are not always aware that they have kidney problems or diabetes, so you should always be aware of your health status before consuming them. As a somewhat unnatural product, it isn’t at all surprising that many doctors suspect long term protein shake consumption as a cause of liver dysfunction. I was diagnosed several years ago with a fatty liver and abnormal enzymes. As a lifetime drug free athlete who never drinks and eats a consistently healthy base of foods, it was a bit of a shock and my physician pointed to my protein supplement intake as a possible cause- as it was something he had seen before in other athletes. I got several other opinions from different gastroenterologists and they all concurred that protein shakes might be the causative factor and so reluctantly I stopped taking them. In time, my liver enzymes stabilized again at normal levels, even though I was still taking in the same amount of protein, only this time it was from real foods.
Protein Shakes & Pregnancy- A Controlled Environment Test
One of the main problems with epidemiological studies is that it is almost impossible to target one particular food as being harmful and or responsible for negative health outcomes. We eat such varied diets of so many foods that the potential negative effects of any one food source is hard to pin down unless a group of individuals were forced to consume a very limited set of foods in a controlled environment. That’s one of the reasons foods that we know as being harmful such as trans fats and high fructose corn syrup remain on the market as it is all but impossible to conclusively say that those ingredients are the cause of our currently high rates of obesity and metabolic- related diseases. Protein shakes are no exception- however there is indeed volumes of research that demonstrate the differences between supplemented protein in the form of shakes versus protein from traditional food sources with regard to overall health outcomes in a controlled environment- and that comes from observations made during pregnancy.
Protein is an important dietary component during pregnancy for gestational weight and the required maternal body weight increases. Supplemental protein in the form of protein shakes were thus considered a potentially convenient method of increasing protein intake for mothers on the go or undernourished females. A comprehensive review of all of the studies conducted to assess the effects of a high protein supplementation intake during pregnancy on gestational weight gain, and pregnancy outcomes show that the protein derived from supplemental sources do not exhibit the same effects as protein from traditional food sources.[6,7,8,9,10,11,12,13,14,15,16,17,18,19, 21] In fact data from animal studies and human trials suggest that high-protein supplementation (i.e. supplementation in which the
protein provides at least 25% of its total energy content) can adversely affect pregnancy outcomes. That being said, available evidence from a review of over 13 studies involving almost 5,000 women provides no justification for prescribing high-protein nutritional supplements to pregnant women as not only were such supplements found to lack any potential beneficial effects, but evidence continues to suggest that they may even be harmful. In two trials of 529 women, high-protein supplementation was associated with a significantly increased risk of small-for-gestational-age birth weight even among undernourished mothers.[9,18] In three other trials, involving 966 women, isocaloric protein supplementation was also associated with an increased risk of small-for-gestational-age birth weight.[14,21,22] (Note: Isocaloric protein supplementation refers to a supplement in which the protein content is ’balanced’ and provides less than 25% of its total energy content, but replaces an equivalent amount of energy in the regular diet) It’s an important finding from the most respected clinical authorities in the medical sciences and a significant insight into the fact that supplemented protein is not a natural part of our dietary intake and that it should not be. The Cochrane Group review ends with an advisory for pregnant mothers to avoid protein shakes and supplements- advice that perhaps all of us should heed.
Protein Shakes & the Pressure Of Advertising
It wasn’t easy stopping the shakes. Everyone else used them and everywhere I went in the gym there were ads with all the top athletes with a shake bottle in their hands. (In later years I learned that few of the athletes endorsing the products ever really took them and I myself have been asked on several occasions to endorse products even given my well known stance against their use). It was hard, and the peer pressure was enormous, but slowly I weaned myself off of the shakes. I thought that perhaps I would see some reduction in my muscle mass a result, but nothing could have been further from the truth. Over the past ten years, I have made better and more consistent gains in strength, muscle mass and conditioning as compared to when I was having protein shakes on a daily basis. It did mean that I had to pay more attention to my diet and plan my meals a bit more, but I credit that transition with being able to naturally maintain a body fat percentage of 7% or less all year round. Not only do I no longer have the stomach upsets that I learned to live with when I drank shakes regularly, but I also feel better and my digestion and energy levels are much better than they were before. Who knew just eating real food could be so beneficial? (Read my article here on how much protein do you really need to build muscle.)
In retrospect, I should have stopped earlier. I never used protein shakes before a contest or photoshoot, so why was it logical to go back to using them when I felt and looked my best without them? These products are a testimony to the influence of pervasive marketing and it is hard to escape it when as much as 60% of fitness magazines today are filled with supplement advertisements- most of them being for protein shakes. They also appeal to our modern microwave mentality for quick over quality. It is a fundamentally flawed argument to say that having a protein drink is better than eating junk food as the two both pose potential risks to your health and are well outside the circle of real foods that our bodies are designed to consume. Such ideas of health relativity are akin to saying that it is better to jump from the 19th floor of a building rather than the 20th. Both lead to the same result while the true logical response is to ignore both choices. The other evil bestowed upon us by protein shakes and the like is the idea that we need something outside of ourselves to be healthy. That we have to purchase something to achieve our goals and that we are unable on our own to do great things. Changing your body in a positive way requires sacrifice and convenience does not always factor into the equation. A strong and healthy body comes from years of dedication, commitment, sensible eating and time, but most certainly not from a protein shake.
Kevin Richardson is one of the most sought after personal trainers in New York City and the founder of Naturally Intense High Intensity Training™. Get a copy of his free weight loss ebook here. If you live in the New York metropolitan area and need help losing weight, building muscle or taking your body to the next level give Kevin and his team a call at 1-800-798-8420. Check out Kevin’s personal training services here.
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