Once you’ve determined the right amount of carbohydrates for your body, and balanced your fats, proper protein intake is relatively easy to determine. For example, if you find that 40 percent of your
macronutrients are carbohydrates, and 30 percent fat, the remaining 30 percent as protein would probably be the optimal amount for you.
As convenient and oversimplified as that may sound, that’s how it turns out for most people. Find the first two pieces of the puzzle and the third falls neatly into place.
However, there’s no need to determine percentages — or grams, calories or any other quantity. Instead, make the appropriate changes as outlined in these chapters, beginning with carbohydrates, and let it all fall into place; your intuition will become a powerful ally.
Coralee Thompson, M.D., simplifies protein needs even more. “At each meal eat the amount of dense protein food such as meat, fish or eggs that fits in the palm of your hand.”
We all need protein every day for optimal health and increased human performance. This is true at all ages, for males and females, and whether you are walking 30 minutes a day or training for a 1,000-
mile race.
Larger body frames and those performing a lot of physical work usually need more protein. Growing children also need relatively higher amounts of protein for development. In fact, throughout life
there is still a significant and continuous need for protein.
Protein is necessary for so many healthy bodily functions, discussing it all would fill several books. Here are just a few examples:
• Enzymes important for balancing fats, digestion and
hundreds of other metabolic activities necessary for optimal
health require protein.
• Protein is essential for maintaining neurotransmitters —
the chemical messengers used by the brain, the rest of the
nervous system and gut for communication.
• Protein is a key element for building new cells, especially
for muscles, bones, organs and glands, throughout life.
• Oxygen, fats, vitamins, hormones and other compounds
are regulated and transported throughout the body with
the help of protein.
• Protein is necessary to make natural antibodies for the
immune system.
• Protein contains key amino acids for health. For example,
cysteine is necessary for the body to make its most powerful
antioxidant, glutathione, and glutamine is used to
fuel the intestine for optimal function, especially for
digestion and absorption of nutrients.
• Protein is important for the production of glucagon in
relation to controlling insulin and blood sugar.

Studies continue to show that the protein recommendations by the USDA are too low. These recommendations have resulted in reductions in protein intake by some people, with dire health consequences.
Even the argument that protein can harm the kidneys, especially those with kidney problems, is losing ground as new studies show that restricting dietary protein in those with kidney problems
can actually increase the risk of death.
Most of this confusion about protein requirements comes from old and outdated research. When determining protein needs, researchers measured the amount of protein taken in through food,
then measured protein by-products to determine the amount lost.
Many studies on protein requirements, especially research that established today’s RDA levels, only measured the protein by-product nitrogen, excreted in the urine. They failed to consider the amount
lost in sweat. This is clearly an important means for excreting the nitrogen from protein breakdown. Urea production alone may not accurately reflect all aspects of protein breakdown. This is one reason
many earlier studies on protein requirements showed such low numbers.
Today, there are better, more accurate ways of determining protein needs through more elaborate measurements. These show that for most people, protein needs are higher than the old recommendations indicate.

How Much Protein?

The answer to this question depends on you — your lean body mass, your level of physical activity and other factors, including what makes you feel best. There is a wide range of healthy and safe protein intake that can provide many benefits. In addition to what has already been stated about finding your protein needs, for those who still need help understanding this important issue I’ll discuss protein needs in grams using the USDA’s recommendations to further put
this subject into perspective.
The problem with this level of protein is that it’s the bare minimum for an inactive person. And, it’s based on body weight and not lean muscle mass. This amount is 0.8 grams of dietary protein per
kilogram (2.2 pounds) of body weight. Based on this, a person weighing about 70 kilograms or 150 pounds should consume 60 grams of protein per day. This can be obtained with two eggs at breakfast, a salad with fish at lunch and a small steak at dinner.
But for most active, healthy people, this amount is insufficient. Recent studies show that protein requirements should be twice that of the USDAsuggestion. Based on these studies performed over the past several years, and my clinical experience, I prefer to recommend a range of normal that includes the minimum amount of 0.8 grams to about 1.6 grams per kilogram of body weight. For most athletes, and those with very physical jobs, the amount of protein may still need to
be increased above this level. Those involved in jogging/running, biking, swimming and other aerobic-type exercise, usually need more protein because the normal continual process of building muscle may actually be greater than that of weight-lifters.
For most active, healthy people, a normal protein intake over 1.0 grams per kilogram of body weight, usually closer to the 1.6 number, is best. Following are some examples of food servings that provide
these amounts of protein:

• For a 175-pound person, the daily protein intake may be
128 grams. The protein foods that would provide this
include three eggs and cheese at breakfast, a salad with a
hefty serving of turkey at lunch and salmon for dinner.
• For a 145-pound person, the requirement may be about
106 grams: two eggs for breakfast, a chef’s salad for lunch
and a sirloin steak for dinner.
• And for the person weighing 125 pounds, who would
minimally require about 90 grams of protein: two eggs at
breakfast, tuna salad for lunch and lamb for dinner.

If you’re 200 pounds or more, or appreciably under 125 pounds, just estimate the protein requirements based on the above numbers.
For example, at 200 pounds, that’s 25 percent heavier, so 25 percent more than 128 grams of protein is 160 grams. Clearly, eating more protein than the body can utilize can be
unhealthy. But if you require more than 100 grams a day, that’s not excessive, it’s what your body needs. Eating the amount of protein your body requires is not a high-protein diet, it’s getting your proper requirements!
Sometimes, when unhealthy people consume normal amounts of protein they won’t feel good because something else is wrong. For example, as protein intake increases, so does your need for water, which helps eliminate the normal by-products of protein through the
kidneys. That’s part of the old argument that protein is a stress on the kidneys; it most certainly is if you are dehydrated.
Or, if you’re under significant stress and your stomach does not make sufficient amounts of natural hydrochloric acid — the first chemical stage of protein digestion — protein digestion can be a problem that could give you symptoms of intestinal distress. Addressing
the cause of the problem — the stress and stomach, not the protein — is the best remedy. Or, another potential protein problem may occur if  you combine a steak with some bread or a potato — this is a significant stress for the stomach, and indigestion often follows.

Amino Acids

Just as carbohydrates are made up of sugars, and fats are composed of fatty acids, dietary protein is made up of building blocks called amino acids. In order to obtain these vital components, the intestine must do its job. First, protein must be efficiently digested in the intestine,
resulting in breakdown into amino acids. Second, these amino acids must be absorbed into the body. Once absorbed, the amino acids are used either as individual products, or recombined as proteins. For
example, the amino acid tryptophan is used to make certain neurotransmitters in the brain. Or, recombining many amino acids provides for the manufacture of new muscle cells.
There are at least 20 amino acids necessary to human nutrition, all of which are indispensable for optimal health and human performance.
While some amino acids can be manufactured in the body by other raw materials from food, others called “essential amino acids” must be taken in through the diet. While amino acids that are made
in the body are sometimes referred to as “non-essential,” this is misleading as all amino acids are essential.
In general, animal foods are the best sources of protein and contain all the amino acids. Overall, the highest-rated protein food is eggs, followed by beef and fish. With the exception of soybeans, which are mostly carbohydrate, vegetable foods individually contain only some of the amino acids. Combining the right non-animal foods can provide a complete amino-acid meal. But eating all the amino acids at one meal is not necessary.
For those who don’t eat animal products, obtaining all the amino acids is accomplished by combining enough variety, since no one plant-based food, except soybeans, contains all the amino acids (although soy is very low in the amino acid methionine). Certain combinations of plant foods, such as beans and rice, or whole grains and
legumes, can provide a complete protein. However, combining meals high in carbohydrates (such as rice, beans, grains, etc.) with protein can reduce digestibility, with the result that some protein will not digest into amino acids, and some amino acids won’t get absorbed.
This is discussed in a later chapter. In the next chapter I’ll discuss
some of best ways to obtain protein from the diet.