Slideshow: High-Protein Diet

The Goal Is Weight Loss

High-protein diets take a page from the low-carb craze. The goal is to lose weight by eating more protein-packed foods, which often means consuming fewer carbohydrates. The portion of total calories derived from protein is what defines a high-protein diet. In a typical diet 10%-15% of daily calories come from protein. In a high-protein diet, this number can be as high as 30%-50%.

Curbing Appetite Plays One Role

Besides curbing appetites, high-protein diets may also change a person's metabolism. When carbohydrates are severely restricted, the body begins burning its own fat for fuel – a state called ketosis. Ketosis may shed weight, but it's also associated with headaches, irritability, nausea, kidney trouble, and heart palpitations.

Starting a High-Protein Diet

High-protein diets come in many forms, and not all are created equal. The most nutritious high-protein plans are low in fat and moderate in carbohydrates, rather than high in fat and low in carbohydrates. The following slides present a variety of foods that fit the high-protein diet bill.

Say Hello to High-Protein Steak

Nothing says protein like a nice juicy steak. And if you're careful to choose a lean cut, you can get all of the protein with far less fat. In fact, a lean cut of beef has barely more saturated fat than a similar size of skinless chicken breast.

Look for Pork Tenderloin

It may surprise you to learn that pork tenderloin is a white meat. What's more, the cuts available today are 31% leaner than they were 20 years ago. If you're interested in a high-protein diet, you may want to plan on pork.

Lots of Protein, Healthy Fats

Fish is a no-brainer -- it's loaded with protein and almost always low in fat. Even the types that have more fat, such as salmon, are a good choice. That's because the fat in fish is generally the heart-healthy kind known as omega-3 fatty acid -- and most diets don't contain enough of this good-for-you fat.

Eggs: Affordable, Convenient, & Tasty

Eggs are perhaps the most classic and certainly least expensive form of protein. The American Heart Association says an egg a day is safe for healthy adults, so you may want to get cracking with eggs when you're on a high-protein diet.

Soy: It's High in Protein, Too

Soy products, such as tofu, soy burgers, and other soy-based foods, can offer a high-protein diet a nutritious plant-based source of protein. An added bonus: Consuming 25 grams of soy protein daily may also help lower cholesterol and protect against heart disease.

Beans: Packed With Fiber, Too

Beans pack a powerful one-two punch – they are loaded with protein and also full of fiber. Along with protein, fiber helps you feel full longer and also helps lower cholesterol. As for the protein content, a half-cup of beans is the equivalent of 3 ounces of broiled steak.

Low-Fat Milk Products

If you want to give your high-protein diet a tasty boost, don't overlook dairy products as a protein source. Milk, cheese, and yogurt are not only protein-rich, they also provide calcium for strong bones and a healthy heart. Strive for 2-4 servings of low-fat or nonfat milk products daily.

Cereal and Energy Bars

Pressed for time? You can turn to high-protein cereal or energy bars to give your high-protein diet a fast boost. Just make sure the bars you choose have at least 6 grams of protein and not too much sugar or fat.

Go Whole Grains, Go Fiber

Most high-protein diets limit grains to a couple servings a day, so you want to make sure the grains you do eat are pulling their weight. That means staying clear of white breads and pastas, which have little to offer nutrient-wise, when compared with their whole-grain cousins. Whole-grain breads, cereals, and pastas, on the other hand, are rich in fiber, which might otherwise be in short supply for people on a high-protein diet.

Keep Fruits & Veggies on the Table

No matter the emphasis on protein, make sure you leave room for fruits and vegetables in a high-protein diet. These nutrient gold mines contain powerful antioxidants that aren't found in most other foods, and research suggests that people who eat plenty of fruits and veggies may lower their risk of cancer.

A Diet Aimed at Dieters

High-protein diets may help people lose weight -- at least in the short term -- because dieters tend to feel full longer when they eat more protein. This alone can cut down on snacking and lead to fairly rapid weight loss. Combine speedy weight loss with the satisfaction of feeling full, and it's easy to understand why high-protein diets are popular. Unfortunately, many people gain back the weight once the diet ends.

More Protein, More Risks?

The medical community has raised many concerns about high-protein diets. These diets often boost protein intake at the expense of fruits and vegetables, so dieters miss out on disease-fighting nutrients -- which may raise their risk of cancer. Other potential health risks include high cholesterol, heart disease, osteoporosis, and kidney disease.

More Saturated Fat, Less Fiber

Many high-protein diets are high in saturated fat and low in fiber. This combination can increase cholesterol levels and raise the risk of heart disease and stroke. The American Heart Association does not recommend high-protein diets for weight loss.

Losing Calcium

People on high-protein diets excrete more calcium through their urine than do those not on a high-protein diet. If a person sticks to a high-protein diet long-term, the loss of calcium could raise their risk of developing osteoporosis.

Protein May Affect Kidney Function

People with kidney disease should consult a doctor before starting a high-protein diet. Research suggests people with impaired kidneys lose kidney function more rapidly if they eat excessive amounts of protein – especially animal protein.

High-Protein Diets: Still Questions

There are no long-term studies of high-protein diets, so their ultimate health impact is unknown. But the experts are sure of one thing: the formula for permanent weight loss is a healthy lifestyle. This includes eating nutritious, low-calorie foods and participating in regular physical activity. Note: Check with your health care provider before making major dietary changes.

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