Part 1 discussed in broad terms the components of the body from a nutrient point of view. This blog begins to make metabolism a palatable and, hopefully, a useful tool in optimizing your health.

Metabolism is in two parts: anabolism and catabolism. Metabolism is orderly and functions depending on the cell’s needs. Anabolism converts to catabolism during growth, recovery and exercise training. Catabolism to anabolism occurs during old age, illness, malnutrition, and restriction diets.

Anabolism:

  • build up, reactions; requires energy

Catabolism:

  • breakdown or degradative reactions, release energy

 Enzymes:

  • proteins that are biological catalysts (reacts with substrate chemical or accessory molecule coenzyme to form energy to lower barrier to reactions), speeding up rates of chemical reactions in the cell, an irreversible reaction creating a product. Coenzymes are generally derived from vitamins, especially B-vitamins.
  • not used up in the chemical process
  • a very specific action (hundreds of chemical reactions are occurring simultaneously in cell)

Even such generalities leaves one realing with the complexity of the running of the body! What we can take from this is our need for all pieces to the nutritional puzzle or our bodies get bogged down in its struggle to survive. No wonder we get fatigued when we do not ensure enough daily required nutrients. Otherwise we are like a machine that starts to squeal and slow down because there isn’t enough oil to keep the machinery running smoothly.

The Intricate Dance of Energy Give and Take

A term that gets lots of print when discussing metabolism is ATP (adenosine triphosphate), the energy currency in cells, creating what is called the ATP cycle:

  1. Muscle mitochondria generates carbon dioxide (CO2) and water (H2O) in the aerobic breakdown of carbohydrates(CHO) and fats. ADP (adenosine diphosphate) and a phosphate group (Pi) are joined together to make ATP in the process.
  2. Carbohydrates such as glucose can also be broken down anaerobically to produce the product lactate, and the necessary energy to generate ATP.
  3. The ATP and energy drives anabolic reactions, splitting into ADP, Pi and useful energy.

At any point where this process is impeded, degeneration begins. You can see the give and take of energy. As energy is expended, our food intake resupplies the body with bio-chemical material for energy metabolism.

Ions, Ionic Compounds and the scary sounding Covalent Compounds

Ions:

We have all heard of soothing negative ion showers, but what is an ion?

Ions are electrically charged particles. Generally, metals form positively charged ions and nonmetals form negatively charged ions (electrolytes). Sodium converts to positively charged sodium and a negatively charged ion. The magnesium ion has two electrons missing. Ions are found in blood, the fluid around cells (interstitial fluid) and inside cells. Many of the mineral elements are found in our foods as ions.

Ionic Compounds:

These are crystalline compounds that are made up of positive and negative ions held together by the force of electrical attraction. When free positive sodium and negative chloride ions are put into a beaker, sodium chloride (salt) is the result. As we have all experienced, opposites attract! Here we have positive and negative combine to make a new substance.

Covalent Compounds:

Covalents are composed of atoms that are joined together by the mutual sharing of electrons between adjacent atoms. Carbon can make 4 bonds: 4 single bonds ( a shared pair of electrons), 1 double bond (4 shared electrons or 2 pairs) plus 2 single bonds. Hydrogen can make only 1 single covalent bond – a pair of electrons shared between the oxygen atom and the hydrogen atom. Oxygen can have 2 single bonds or one double bond. Nitrogen can have 3 single bonds or 1 single and one double bond.

pH:

Think of the acid-base (negative logarithm of the hydrogen ion concentration of a solution) as a linear scale from zero to fourteen. 7 is cosidered neutral. 0 is most acidic. 14 is most basic or alkaline.

The stomach pH is about 1.5 (quite acid)

Blood pH 7.4 (almost neutral).

Small intestine about 8 (slightly basic or alkaline).

Part 3 deals with protein to demonstrate its vital need in nutrition.

Janet Wiebe

Advertisements