The Power of Protein
Carolyn Classick-Kohn,MS,RD

Popular diets come and go, but the problem of being overweight remains. In the past few years, high protein diets have made a comeback. But, if they are the “magic bullet”, why is the incidence of overweight and obesity increasing around the world? This week, I want to address some myths and misunderstandings about the role of protein in a healthy diet.

Protein - What does it do?

Proteins are unique, complex structures that serve a variety of roles in the human body. Proteins are made up of twenty different amino acids, of which ten are called “essential” because the human body cannot make them from other structures. Proteins determine our basic chemical make-up, the DNA, and have many different roles in the body. They make up the muscle mass, the collagen and elastin of the skin and connective tissue, and form enzymes, which are essential for various chemical reactions in the body, including the breakdown of food, and the building, repair and growth of tissues. Clearly, proteins are very important to the body. But what role does it play in the diet and in losing and maintaining weight? How much do we need?

Claims v.s. Facts

Claim: Supporters of high protein diets claim that eating more protein and reducing carbohydrate is the best way to lose weight.

Fact: The only way to lose body weight is to eat fewer calories than the body needs to maintain its current weight and exercise requirements. At first, a high protein, low carbohydrate diet causes rapid weight loss. In the first 24 to 72 hours, the body uses up its glycogen stores, and the water released in this process is eliminated as well. This causes a rapid weight loss, which settles down after that. With a high protein, a lot of water is excreted beyond that because of the need to dilute the by-products of protein metabolism, causing a lot of water loss. After 60 to 90 days on any reduced calorie diet, the balance of the nutrients (high protein or high carbohydrate, low fat versus high fat) has no impact on the rate of weight loss. What matters is the total calorie intake.

Claim: Limiting carbohydrates help to control appetite, carbohydrates are “addictive”.

Fact: Complex carbohydrates are a source of energy, short and long term, and they help to stimulate metabolism. When metabolism is sped up, calories are burned better, which can lead to hunger between meals. Eating smaller meals more often will help this. “Cravings” can occur without true hunger, it is a desire for a certain food, not necessarily a need for it.

Claim: High protein diets are more healthful than high-carbohydrate diets.

Fact: High protein diets may eliminate many of the best sources of vitamins and minerals critical to good health because they limit whole grains, fruits, vegetables, and beans. They can be very low in fiber, and are very difficult to follow past a couple months, which can lead to regaining lost weight.

Some Benefits?

In the short term, high protein diets can suppress appetite because many induce ketosis, a condition where the body burns fat for fuel in the absence of adequate glucose. This is because the body is very good about turning extra glucose into fat for storage, but fat cannot be turned back into glucose. So, without adequate glucose, the body must burn fatty acids, which causes ketone bodies. This can trick the brain into suppressing hunger. It also causes fast weight loss temporarily, again, because of the loss of water.

In reality, drastically cutting down on carbohydrates by eating a high protein diet is just another gimmick to get people to eat less food. It may work in the short term, but can you live with this diet? After all, the harmful effects of overeating animal foods that are high in saturated fat and cholesterol are well known - they increase blood cholesterol levels and improve one’s chances of getting a heart attack!

Are you getting enough protein?

The diet plan you are given is one based upon the proper balance of nutrients for good health and for weight loss. It is lower in fat, but is not low in protein. But is there enough protein? I know that many of you are used to eating larger quantities of meat. Here are some facts:

The average person needs about .8 grams of protein per kilogram of body weight. This amounts to about 45 grams of protein for women and 56 grams of protein for a typical man. For highly active people such as athletes, protein needs increase to about 1.2 - 1.4 grams per kilogram body weight. In more extreme cases, experienced body builders may need 1.6-1.7 grams of protein per kilogram of body weight, because they are generally larger, more muscular people.

Even at these higher protein needs, the requirement can usually be satisfied with a balanced, healthy diet with no more than 20% calories as protein. This is because athletes (and especially body builders) require and eat more food, so their total protein intake goes up with their calories.

Most athletes and body builders aren’t following a reduced calorie plan - they don’t need to. However, when the average person combines vigorous exercise with a reduced calorie plan, you are putting yourself at greater risk for having an inadequate intake of protein, fat, and carbohydrate! You need more food to cover your body’s activity, even if your aren’t a professional athlete.

With a weight loss diet, protein needs are based upon desirable body weight, not current weight. Protein is recommended at about 1.5 grams per kilogram. Generally, a diet that contains about 70-75 grams of protein will be adequate to meet the needs during weight loss.

Since your diet plan contains about 20% of calories as protein, your protein needs should be covered. However, be aware that if you are trying to lose weight, and are exercising vigorously, you will certainly need more calories (to get more protein, fat and carbohydrate) to meet your energy needs than a person who is sedentary. Let me know if you have increased your exercise, you may need an increase in your calorie level to cover your new requirements. If you don’t eat enough to cover your exercise needs, you may feel tired or “burned out” instead of invigorated, a sign that you may need more fuel. (This is the great thing about exercise, you can eat more, because you are burning it off!)

Boosting your food choices with protein

For those of you who are not used to eating smaller amounts of meat, it may seem like your diet is low in protein. However, don’t forget, protein also comes from grains, vegetables, beans, soybeans, and low fat dairy products. Choose a variety of these foods instead of junky snacks (even if they are fat-free, they are likely to be low in nutrition!)

  • A good way to boost your protein intake on a limited calorie budget is to choose very low fat animal foods. Fish, skinless poultry, and fat-free dairy products all contain more protein, calorie for calorie than an equal amount of higher fat meats and dairy products. This is another advantage of choosing low fat animal foods.
     

  • Another way to get a little extra protein is to choose fat sources that contain protein as well. By this I mean choosing nuts and seeds as a source of fat sometimes rather than margarine and oils.
     

  • Spread out your meals and eat smaller, more frequent meals that are a mix of fat, protein, and carbohydrate sources. This can help keep you satisfied longer and provide the energy you need to get through your day. The protein and fat will take longer to digest and help contribute a feeling of satisfaction rather than eating “fat-free”.
     

  • Last, eat your basic plan first. Make sure that you get at least all of the servings that are recommended in each food category - skipping these foods and replacing them with low nutrient snacks will reduce your protein, vitamin and mineral intake. Have your “fun” foods (occasional desserts, alcohol beverages, sweets) in addition to, not instead of, your healthy eating plan. If you eat from your plan first, you probably will have less of a desire to eat extra foods anyway because you will be satisfied!

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