Wednesday, March 30, 2016

Eating right means getting enough of the right kind of Protein



Topics:
  • protein
  • complete protein
  • amino acids (AA)
  • limiting amino acid
  • essential and non-essential amino acids (conditionally essential)

Protein deficiency is the most serious nutritional problem in the world.

It is less of a problem in US - except the following groups are likely to be at risk:
       Pregnant and lactating women   
       Newborn babies    
       Poor people
       Old people
       People who are Ill - especially children
       People who avoid protein-rich food

Second only to water in the body's physical makeup, protein makes up about 20% of our body weight.  Protein is necessary to the makeup of muscles, hair, nails, skin, eyes and brain - well, every part of the body.   Protein makes up the components of our immune system, hemoglobin, hormones and all bodily functions.
You must eat protein to provide the building blocks for the various amino acids required for the body to grow, function and make repairs.   Your body also needs vitamins, minerals and fatty acids to work with the various  Amino Acids.

Proteins are complex molecules which are comprised of a combination  of 22 naturally occurring amino acids (this number varies depending on the reference).  Each protein has its own unique amino acid sequence, structure and function in the body.   Essential amino acids are those which our bodies cannot synthesize - that is, they must be acquired daily in the diet.

Animal foods are considered as 'complete' proteins because they contain the 8 (or 9, depending on the reference source) essential AAs.  Vegetables and fruits contain adequate levels of many of the essential AAs, but may be low in others.  By definition these are incomplete protein foods.

There are some important facts about the way that the body deals with proteins.

  1. The very young, very old and very ill will have extra-ordinary amino acid needs.  This includes the non-essential AAs as well as the essential ones.  In other words, the body may not be capable of building a non-essential (but necessary for that individual) AA fast enough to meet specific body nutritional needs.
  2.  It is critical that ALL essential AAs be present in adequate amounts!  If just one is low or missing, even temporarily, protein synthesis will fall to a low level - or may stop all together.  This is one reason that persons on a vegetarian or very low protein diet are at greater risk of protein malnutrition. To obtain a complete protein meal from incomplete protein foods, one must combine foods so as to balance one with a low or missing AA with a food with an adequate amount of the low or missing AA(s)
  3. Older people are at special risk because they often prefer a low protein diet.  As a group they often have a poor appetite, don't smell aromas well and don't taste worth a darn.    If they are living alone it is likely to be too much trouble to prepare a healthy meal.  They often have digestive complaints - not to mention that many drugs interfere with digestion and absorption of the foods they do eat.  While many older people take a multi vitamin supplement, they do not often include a protein supplement.

Daily recommendations from the Institute of Medicine

As you can see the requirement vary by  age and amount of energy expended - as well as general health and demands of growth and tissue repair. WebMD also recommended that 10% to 35% of your daily calories come from protein.

Food labels show the percent of 50 grams based on a 2000 calorie diet for adults  The following recommendations are VERY general...
     Babies     10 grams
     Kids         19 to 34 grams
     Teen Boys     up to 52 grams
     Teen Girls     46 grams
     Men         56 grams
     Women    46 grams
     Pregnant and Lactating Women     71 grams

Note: Vegetable proteins have low biologic value for humans because each one has a  low level of  one or more essential AAs.  Examples:
                      Plant Source    <--->     Deficient Amino Acid
                      Corn                           Tryptophan, Threonine
                      Grain Cereals             Lysine
                      Legumes                    Methionine, Tryptophan
                      Peanuts                       Methionine, Lysine
                      Soybeans                    Methionine

To arrive at optimal daily requirements is a challenge because the need varies so much.
  1. The amount and kind of protein{s} one needs depends on sex, body size and activity.
  2. Age has to be factored in - as does the need of a pregnant or lactating mother.  

Signs of Amino Acid/Protein deficiencies

  1. Lack of amino acids and proteins is exhibited by growth and tissue abnormalities.  
  2. Adults may suffer from lack of vigor and stamina, mental depression, poor resistance to disease and slow recovery from disease and injury.  
  3. In fact, in times of stress, such as surgery, protein needs increase dramatically.

Which Amino Acids are important?

Essential (must be provided daily)    **Non-Essential or Conditionally Essential
   Histidine                                              Alanine
   Isoleucine                                            Arginine* (essential for growth)
   Leucine                                                Asparagine
   Lysine                                                  Aspartic Acid
   Methionine                                          Cysteine* (some enzyme deficiency diseases)
   Phenylalanine                                      Glutamic acid
   Threonine                                            Glutamine*
   Tryptophan                                          Glycine
   Valine                                                  Ornithine
                                                               Proline*
                                                               Selenocysteine*
                                                               Serine*
                                                               Tyrosine* (some enzyme deficiency diseases)
* Starred AAs are essential in some circumstances
**Note:  this list varies by reference

 Check out the Super Food value of Spirulina

These statements have not been evaluated by the Food and Drug Administration. 
This product is not intended to diagnose, treat, cure, or prevent any disease.