Can You Eat Too Much Protein?

Protein is acclaimed within the consumer health world for everything from building muscle to preventing weight gain. The $6.6 billion protein supplement industry offers an array of products in the form of powders, bars, and shakes that allow consumers to easily exceed recommended protein intakes. Now, for the first time in history, the Dietary Guidelines for Americans is concerned that certain segments of the population are consuming excessive protein quantities. This begs the question: are consumers getting too much of a “good” thing?

Protein is an essential part of the diet, containing certain amino acids that the body cannot produce on its own and needs for healthy function. Amino acids provide important building blocks for muscle, bone, and tissue as well as enzymes and many hormones. The average adult can meet the recommended daily allowance – 46 grams per day for women and 56 grams for men – by regularly consuming moderate amounts of protein-rich, whole foods, such as meat, fish, dairy, beans, or nuts. For example, a cup of chopped chicken contains 44 grams of protein, a cup of Greek yogurt or tofu contains 20 grams, and three eggs or a cup of lentils contains 18 grams. A canned protein beverage, on the other hand, can have as much protein as an 8-ounce steak.

The 2015-2020 Dietary Guidelines for Americans concluded that adolescent boys and men generally consume too much protein. As result, they recommend that these segments of the population “reduce overall intake of protein foods” and eat more vegetables. As males represent approximately half of the U.S. population, this recommendation and its public health implications are alarming.

The protein craze seems driven, at least in part, by the misconception that more protein means more muscle. However, the body does not store excess protein; it is either excreted in urine or turned into fat. Therefore, an individual who consumes 300 grams of protein per day is no better off than someone eating the recommended 56 grams. Moreover, with a high-protein diet, it is possible that other valuable nutrients, like health fats, complex carbohydrates, and micronutrients are being displaced.

Many studies have investigated the short-term outcomes of high-protein diets, but relatively little is known about the long-term effects of chronically high protein intakes. Short-term studies suggest that high-protein, low-carbohydrate diets promote weight loss while preserving lean muscle and satisfy hunger (1, 2, 3). However, a large population study found a link between diets habitually high in protein from meat and increased risk of diabetes. Additionally, there are concerns about high protein diets and calcium loss from bone, kidney damage in those harboring silent kidney disease, and cancer risk.

To prevent excessive protein intakes, avoid protein supplements and eat a variety of healthy foods, with a strong emphasis on plants. As always, consult a doctor or dietician before making major changes to your diet.

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Dr Kara

My journey to find a balanced way of living led me to a Ph.D. in Nutrition at the University of Wisconsin-Madison and a Master’s in Public Health at the University of California-Berkeley. My studies and experiences afford me a deep understanding of diet and lifestyle factors that contribute to optimal health. I contribute to projects in the U.S. and abroad that improve the health of individuals and families through nutritious foods. I believe the foods we eat impact our lives in so many ways, ranging from nourishing our body’s cells and tissues, to supporting emotional, physical, and social wellbeing. I am thrilled to be a part of the Moxy Kitchen team and support the development of flavorful, easy-to-use food products that add a nutrient-dense punch to daily meals.