Protein is one of the most commonly supplemented macronutrients, because it's relatively cheap, has many health benefits and is commonly propagated as a meal replacement. What most people don't realize though is that too much protein (usually in the form of protein shakes) can actually have adverse health effects. These negative consequences range from reduced kidney efficiency to weight gain.
The Institute of Medicine of the National Academies (IOM) recommends that the average person should consume 0.8 grams per kilogram of body weight, or 0.36 g/lb, of protein per day. That means that a 150 lb male should consume 54 g of protein a day, which is fully achievable with the average diet. The IOM also recommends that only 35% of your daily caloric intake should be from protein; in a 2000-calorie diet, that's 700 calories or 175 grams. Protein intake exceeding this can result in adverse health effects.
Negative Consequences
The consumption of protein over these recommendations can lead to renal damage, gout attacks and weight gain. The continued consumption of protein over the IOM's recommendations can damage the kidneys via hyper-filtration, decreasing their efficiency. This is especially true for people who already have renal complications.
High-protein diets have also been associated with gout attacks by increasing their severity and frequency. Gout forms when high levels of uric acid in the blood stream crystallizes and accumulates around the joints, causing severe pain. The formation of uric acid is accomplished by breaking down purines which occur naturally in meats. A high-protein diet and overindulging in meats can cause you to have more severe cases of gout.
Lastly, because protein breaks down to four calories per gram, excessive consumption of protein can lead to weight gain. Any protein left over after your body uses what it needs for maintenance and muscle growth will more than likely be turned to fat. This in particular can be of great concern for people with weight issues or if they are having problems losing weight.
The adverse effects of excess protein are a real concern. While 35% of your daily caloric intake seems like an extraordinarily high amount, many people do consume this amount and more via high-protein diets and protein shake supplementation. Likewise, going over your IOM-recommended daily allotment can cause problems for people trying to decrease their weight or for people with gout. It's important to keep in mind the IOM's recommendations and consume in moderation, even something as beneficial as protein.
