Getting Your Daily Protein

It's easy to get all the protein we need without eating meat. While it is not easy or inexpensive to store meat, plant protein can be stored very economically for a long time.

Important points to remember about protein:

• The RDA of protein for a 79kg (174 lb.) adult male is about 63 Grams. Women (calculated for a 63kg or 138 lb. woman) need about 50 grams. (0.8 Grams protein per Kilogram of body weight.) Pregnant and nursing women require about 30% more. Children need as much as adults because they are growing. A rapidly growing child can require 2 to 3 times more protein than an adult by weight.
• A safety factor was built into the RDA for protein and actually represents a little over twice as much as our bodies actually need.
• Our body gets all but 1/6 of the protein it needs from recycling old body tissue. This amounts to 100-300 grams. The 1/6 we don't recycle must come from essential amino acids we eat.
• Hard work does not require more protein!
• Protein is required for growing, body repair, and maintenance. A person with serious physical injuries or illness requires much more protein.
• If we do not get enough protein, our bodies will steal it from our muscles. This is also true when we are ill. We need more protein, but often can't eat it.
• North Americans generally eat 3 to 5 times more protein than they need. The protein not needed is broken down further and most of it is used to make energy. However there is some left over product from this process which is not good for our bodies.
• We can only absorb about 25 grams of protein at one time. The rest is broken down and burned or stored as fat.
• Plant protein is absorbed at about 70-90%, animal protein at 85-100%. There is concern among some about plant protein not being absorbed as readily as animal protein. This is not a problem as we in North America presently eat 2 to 3 times the RDA for protein anyway.
• North Americans have been brain washed into believing they must get their protein from meat. Third world nations all over the globe, who get enough calories in their diets, eat little or no meat yet many of them are in excellent health from eating only plant protein.
• Men require about 2900 calories and women require about 2200 calories per day. Hard work requires more.
• Our bodies digest the proteins we eat, separating them into amino acids which are absorbed into our blood stream.
• Our bodies use 22 amino acids to make 50,000 different proteins we must have to be healthy.

• Our bodies can make all but 8 of these amino acids. The 8 amino acids it can't make are called essential amino acids, as we must get them from the foods that we eat.
• The RDA for the essential amino acids follow:

(From the National Academy of Sciences
Recommended Dietary Allowances 9th ed. 1980)
Requirement of Essential Amino Acids (per kg body wt) mg/day.

• It isn't necessary to mix plant protein to get a complete protein. After we eat, our bodies store a several hour supply of amino acids in our blood, called an amino acid pool. We may eat a meal that is deficient in one essential amino acid or another. But if we eat a food with the missing amino acids sometime during the day they will combine in our blood and give the necessary nutrition to our individual tissues.
• Contrary to what many people believe, it is very easy to get the amino acids we need from almost all foods. Except for fruits, sugars and fats and oils, nearly every food has enough protein in it to supply us with the necessary amino acids if we eat enough of it to get a day's worth of calories. The table below was generated by the web page author to test this theory. As this is indeed the case, eating a normal diet, we will just about have to be in a starvation situation to not get the amount of protein our bodies need.
  
  

Understanding the following table:

• Column 1 lists the food.
• Column 2 lists the letter for the limiting Amino Acid. The limiting amino acid has the least amount of the RDA for all the essential amino acids in that food. Therefore, if a food has enough of the limiting amino acid for our bodies, you can take for granted that it also has enough of the other 7 essential amino acids. See the bottom of the first table to see the limiting amino acid reference letters.
• Column 3 lists the number of grams of food a 79kg man must eat to get just 100% of the RDA of the limiting amino acid.
• Column 4 lists the number of pounds of food a 79kg man must eat to get just 100% of the RDA of the limiting amino acid.
• Column 5 lists the number of calories of the food a 79kg man must eat to get just 100% of the RDA for the limiting amino acid. This is one of the main columns you want to keep your eye on. As it passes 2,900, our theory of every food having enough protein if we eat at least 2,900 calories gets tipped on its head.
• Column 6 lists the percentage of protein calories to total calories for the individual food. For all the foods you eat during the day, ten percent protein calories to total calories is considered optimum. For example, for your diet to meet this target, of a total 2,900 calories, 290 calories of it should be from protein. You will see from the table below the high numbers in this column for meat and legumes require us to eat a lot of the less dence calorie foods to balance this number out.
• The table is sorted with the foods requiring the least amount of weight for a 100% RDA of protein displayed first. The following table containing a total of 72 foods has been broken up to permit comments.

Amino Acid References:

• M=Methionine+Cystine
• T=Tryptophan
• L=Lycine
• V=Valine
• I=Isoleuine
• P=Phenylalanine+Tyrosine
• A=Several or all Amino Acids missing
  

It's not at all surprising that the meats would be first listed as the most protein dense foods. In fact, dried lean meat is almost 100% protein. We as a society enjoy our meats, but there can be a problem with eating too much protein. Some researchers today suggest that anything over two times the RDA of protein begins to be hard on our systems. This alone is good reason why meats are to be used sparingly. If we ate only chicken, for example, to get our 2900 calories, we would get 16.6 times the protein we needed. This would have negative consequences for any of us. Too much meat protein contributes to osteoporosis, gouty arthritis, cardiovascular disease and stresses the kidneys. Most researchers believe, however, that meat isn't bad for us if not used in excess. Of course, with meat, our theory about 2900 calories of food meeting the minimum amino acid requirements holds true as the lowest protein meat in the sample, mackerel, only requires 227 calories to give us a complete protein. Now back to the table.

Next in protein density comes the legumes. Hopefully, you remember the tables are sorted by the weight of food required to give 100% of the protein required. This is why you see a couple of non-legume items scattered in with the above sample. The grains oats and rye are excellent protein sources when looking only at the essential amino acids, as are the eggs in this sample. Legumes are great protein sources and contain many other important ingredients as well. Even though legumes are low in Methionine, they contain enough to require very little of the food to give enough amino acids to meet daily needs. Again, our theory holds true. Our least dense protein food, great northern beans, only requires 640 calories, equaling 189 grams or 7 ounces of food. Keep in mind that for all the legumes, this is dry weight. To determine what the weight would be if they were rehydrated raw, multiply the dry weight by 2. Of course, the amino acid content and calories will remain the same. For cooked and drained legumes multiply the dry weight by a factor of 2.2. (Kidney beans were used for the sample.)

And now we have the grains as the next protein dense food. Grains are traditionally low in the amino acid Lysine. This block of foods also represents the foods that we should be eating the most from in our diets. They are generally rich in complex carbohydrates giving us good sustained energy over a long period of time. And they are mostly over the 10% protein calorie to total calorie figure. They are low in fats and cholesterol, and have a good ratio of many of the B vitamins and essential minerals. Does our theory still hold true? Yes. Millet, our lowest food in the above category requires 1,690 calories and 447 grams or 1 lb. to meet our RDA for protein. And at least half of the grains require only half of this amount.

Here are many of our vegetables. Again, we've thrown in a couple of non-vegetable items as this is where their sort order falls within the table. Vegetables are also very good in our diets in rounding out many of the missing vitamins, minerals and roughage we haven't seen in large amounts in the tables above. They add great variety and some of them are even staple items, like the potato. Does our theory still hold true? Yes. But bananas come closest to busting our 2,900 calorie theory, requiring 2,643 calories to give us a complete protein for the day. However, at this point another problem rises to the front burner. And that is the food is so scarce of calories and protein that to get the 2900 calories or the needed protein it would be almost impossible for anyone, except maybe a teen-ager, to eat that much. For example we would have to eat 6.3 lb. of bananas. We'd be banana eating son-of-a-guns (not to mention if our one food was celery or cucumbers requiring us to eat 17.4 lbs.).

In theory and practice, if we eat our RDA of 2,900 calories from any of the above foods, we will get the protein our bodies need. This is true if we eat only one of them, or a mix of them in any amount. It almost goes without saying that this also holds true for women as the RDA per kilogram of body weight is the same between the sexes. A 63kg (138 lb.) woman requires 2,200 calories. She needs proportionately less protein than a man. Now we move into much less friendly territory.

Fruits, refined sugars, and fats and oils. Does our theory hold out now? No. Of the fruits that have all the amino acids, we would have to eat much more than the daily caloric intake of that food to get enough protein. And that's if we could even eat that much fruit. Is this a problem with fruits? Not really, unless we are on a fruit intensive diet and eat no high protein foods. Do we then need fruit in our diets? Of course, for a multitude of reasons.Fats, oils and refined sugars give us a much greater problem when it comes to protein. And that's because we are so addicted to them. Fats, oils and refined sugars have no proteins (or hardly any other nutrients, for that matter). Fats and oils are the most calorie rich foods there are by weight, with 1 gram giving us 9 calories of energy. Incidentally, protein, and carbohydrates including sugars and starches, are considered energy rich yet only have 4 calories per gram. It is possible, though difficult, to have a protein deficient diet by eating nothing but fatty or sweet junk food (not to mention all the other deficiencies we would have.) Fats aren't all together bad, however, as we need some saturated and unsaturated fats in our system.

Protein, and their building blocks, the amino acids, are some of the most important nutrients we need on a daily basis.