Makers of protein shakes may say that their products help lower body fat or promote weight loss. But protein shakes aren't a magic way to lose weight.

Some studies find that consuming a higher than usual amount of protein in your diet may offer benefits. For example, eating or drinking products that are high in protein may help you lower body fat, keep lean muscle, feel full and lose weight. But evidence is limited. And studies often test many protein sources and not only protein shakes.

Replacing meals with protein shakes may help you lower your daily calories, which can help you lose weight. But in time you'll need to start eating solid food again. Eating solid food may cause excess weight to return if you don't make smart food choices. And if you rely too much on protein shakes to replace daily meals, you'll miss out on the healthy benefits of whole foods.

Since protein has calories, consuming too much can make it harder to lose weight. This can happen if you drink protein shakes along with your usual diet and you're not eating less calories or exercising.

The Dietary Guidelines for Americans state that an average adult needs about 46 to 56 grams of protein a day. This amount depends on your weight and overall health. As long as you're eating a healthy diet, you likely don't need to add extra protein through protein shakes or other sources.

Keep in mind that the key to losing weight is burning more calories than you consume. Choose healthy foods, such as:

• Fruits
• Vegetables
• Whole grains such as brown rice or whole-wheat bread
• Low-fat or fat-free dairy products such as milk, yogurt and cheese
• Protein-rich foods such as skinless chicken breasts, eggs, fish, beans, peas, lentils, soy products, nuts and seeds

And avoid eating too much food with added sugars, salt or saturated fat.

Also add physical activity to your daily routine. Aim for about 30 minutes of activity, such as brisk walking, most days of the week. And do strength training of all major muscle groups at least two times a week.