With protein being added to most food products, from pancakes and cheerios to pasta and pudding, we’ve been led to believe that one can never consume enough protein. But while protein may be a primary building block for one’s muscles, bones, and many hormones, research has shown that there are many detrimental consequences to diets with high protein intake. The consequences include weight gain, extra body fat, stress on the kidneys, dehydration, and leaching of important bone minerals.
According to The New York Times, “A study published last March found a 75 percent increase in premature deaths from all causes, and a 400 percent increase in deaths from cancer and Type 2 diabetes, among heavy consumers of animal protein under the age of 65—those who got 20 percent or more of their calories from animal protein.”
So why is excess protein so bad for you? Firstly, you will ultimately gain weight. In a recent Spanish study, researchers analyzed approximately 7,000 study participants.Those who ate high-protein diets had a 90 percent greater risk of gaining more than 10 percent of their body weight during the study. If you eat more protein than your body requires, it will simply convert most of those calories to sugar and then fat.
Second of all, excess protein can damage your kidneys. While consuming protein-rich foods, you will also be consuming nitrogen. With a normal amount of protein, your body will excrete the nitrogen. When consuming too much protein however, your kidneys have to work harder than normal, in order to rid of all of the extra nitrogen, causing stress to your kidneys. Cassie Bjork, a registered dietician, explains that this is harmful in the long run, especially if you are a long-time high-protein dieter. Bjork also explains that high amounts of nitrogen are toxic, and so in order to compensate for the increased nitrogen levels, the body uses fluids and water to flush it out, leaving you thirsty.
Thirdly, and perhaps most surprisingly, too much protein can cause bad breath. Isabel Smith, a registered dietician, states, “When you don’t eat enough carbs, the body burns fat and protein for fuel. It does so by a process called ketosis. Unfortunately, ketones have an awful smell that cannot be masked by brushing or flossing.” Who wants to walk around with smelly breath? More importantly, who wants to be stuck with other people’s smelly breath?
In addition, too much protein may also play a role in aging. According to Valter Longo, director of the University of Southern California’s Longevity Institute, “Proteins and their amino acids regulate the two major pro-aging pathways.” By “up-regulating” those pathways, you may promote higher rates of both death and disease. The New York Times explains that a plant-based diet, one that is naturally low in protein, can prolong life by blocking the mTOR protein, a protein that is linked with aging.
Finally, excess protein can increase your risk of cancer. A study that followed thousands of adults for about twenty years showed that those who had a diet rich in animal protein were four times more likely to die of cancer than those who followed a low-protein diet. Protein can have an effect on the mammalian target of rapamycin (mTOR) pathway. When you eat the amount of protein your body needs, the mTOR remains inhibited, helping minimize cancer growths.
“If you are eating enough calories, it’s really hard to not get enough protein,” says Marion Nestle, a professor of nutrition and public health at New York University. A person needs about one-half a gram of protein per pound of lean body fat. This translates to about 40 to 70 grams of protein per day for the average person. So unless you are pregnant, or competing athletically, drop the excess protein shake our society seems to be advertising as necessary.