From diet books to news headlines, protein is in, while carbohydrates and fats are out. Without this very important nutrient, we wouldn't be able to build, maintain and repair the body's tissues. Of the 20 amino acids that are used to make protein, nine cannot be produced by the body alone. These nine essential amino acids can only be obtained from the foods we eat. But are we eating too much?
The National Health and Nutrition Examination Survey found that the average American male consumes 102 grams of protein per day, while the average female eats about 70 grams. That's almost twice the daily recommended intake established by the Food and Nutrition Board. For most healthy individuals, it's recommended that 10-15 percent of our daily calories come from protein (about 56 grams for men and 46 for women). This may sound like a lot, but it's easier to meet those needs than you think. Consider this: One cup of milk (8 grams), a 3-ounce piece of meat (21 grams), 1 cup of dry beans (16 grams) and an 8-ounce container of yogurt (11 grams) provide 56 grams of protein, according to the CDC. That didn't take much.
Why can too much protein be a problem? For starters, meat is a major source of protein in the American diet, and animal foods high in protein are often high in saturated fat. According to the American Heart Association (AHA), foods high in saturated fat can increase risk of stroke, coronary heart disease, diabetes and some types of cancer. Additionally, people who have a problem processing excess protein may be at risk for kidney and liver disorders and osteoperosis. The AHA does not recommend high-protein diets for weight loss, stating that high-protein diets can "restrict healthful foods that provide essential nutrients and don't provide the variety of foods needed to adequately meet nutritional needs." Additionally, if you consume more calories than you burn, any extra calories will contribute to weight gain.
To calculate individual protein needs, it's important to factor in body weight, physical activity level and health status. The average person who leads a relatively sedentary lifestyle needs about 0.36 grams of protein per pound of body weight. That means if you are healthy, weigh 140 pounds, and occasionally ride your bike to work, you only need about 50 grams of protein per day.
And exercise doesn't necessarily increase protein needs. According to the Academy of Nutrition and Dietetics (AND), if you are working out for an hour a few times a week, you probably don't need to take in extra protein. For endurance and strength-trained athletes, AND recommends consuming 0.5 to 0.8 grams of protein per pound of body weight daily, which can generally be obtained through the diet without the use of supplements.
So what are the best protein sources? While animal proteins usually contain all of the essential amino acids forming complete proteins, eating a varied, plant-based diet can also meet all of your protein needs. One cup of dry beans, for example, contains about 16 grams of protein per serving, while a cup of brown rice contains 5 grams. Together these foods form a complete protein and also provide a healthy dose of fiber -- which helps lower cholesterol, promotes regular bowel movements, regulates our blood sugar and helps us feel full. Plant-based proteins also don't have any saturated fat, and are usually lower in calories.
The take-home message: Before gulping down that protein shake after a workout, or subbing a large steak for carbs and fats at lunch and dinner, calculate your actual needs to make sure the extra protein is really necessary. It's probably isn't.
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