Bone is not a static entity; it is a dynamic organ that is constantly ebbing and flowing with all the shifts of the body; just like your liver or pancreas. Bones act as reserves of minerals important for the body, most notably calcium andphosphorus. In vivo bone (living bone in the body) contains between 10% and 20% water and of its dry mass, approximately 60-70% is bone mineral. Most of the rest is collagen and inorganic salts and as you will see, this is a very important factor.
With that being said, this article will keep to basics; as a discussion on what bone actually is and does can get very extensive. This will only consider the biochemical aspect and not the biomechanical (weight bearing exercise) or the hormonal aspects.
Commonly, bone health is thought to be related to vitamin D and calcium metabolism. While that is very true, there are other factors that are very important.
Let’s first discuss vitamin D (D) and some of the basic affects that it has in general. (For a very detailed description of vitamin D’s benefits, please check out www.mercola.com) Most people have heard that vitamin D aids in the absorption of calcium (Ca). D picks up Ca from the gut and puts it into the blood. The similarity of the effects of D to the parathyroid hormone is striking. In fact, this hormone has been called the “winter hormone” because it is suggested that it performs when people do not get enough sunshine during the winter months.
Some signs and symptoms of D deficiency are:
· Hyperirritability (Insomnia, restlessness, cramps)
· Tetany (muscle spasms)
· Lung conditions (bronchitis)
· Lowered resistance (worse in winter due to lack of sunshine)
· Hypotension (LOW blood pressure)
· Epistaxis (nose bleed)
· Delayed healing (bed sores, ulcers)
The synthetic varieties of D have been found to be toxic. Examples of synthetic D are: ergosterol and ergocalciferol. This is not true of the natural varieties, as they can be tolerated at higher levels. Some examples of good quality D are cholecalciferol (make sure to get an emulsified version as this bypasses the liver and goes straight to the lymphatic system) and what is obtained from cod liver oil. However, if you are looking to use D therapeutically, the fish liver oils may not be the best bet as they also contain vitamin A. Vitamin A and D tend to “compete” for absorption. Skin exposure to natural, uninhibited sunlight is the very best way to increase blood levels of D. Very high levels of D from sunlight are never toxic when balanced with other factors. D absorption is also facilitated by vitamin K which is found in deep green leafy veggies like spinach and alfalfa.
Now…on to the most talked about mineral…Calcium.
There is more Ca in the human body than all of the other minerals combined. More Ca supplements are sold than any other mineral, but most of them are not absorbed from the gut. Ca is essential for various body functions beyond bone mineralization, including, but not limited to:
· muscle contraction
· nerve conduction
· maintenance and function of cell membranes and membrane permeability
· blood coagulation
· Proper functioning of many enzymes.
White sugar has an extremely negative effect on Ca balance in the body.
The most common form of Ca sold is the carbonate form. This is limestone (rock) and is very hard to absorb, very hard. However, there are several types to look for that are very easily broken down and absorbed. These are: citrate, lactate, and glycerophosphate.
Most of the population is aware that in order to be utilized, Ca must be with magnesium (Mg), phosphorus, and many other minerals.
The most common source of phosphorus in developed countries, unfortunately, is soda pop. This is in the form of phosphoric acid and not only is detrimental to Ca balance, but also upsets the delicate pH balance of the body. The pH balance of the body is also VERY important for bone health and that will be a discussion for a later date.
Within the nervous system itself, different minerals function differently. Mg tends to have a calming affect to the nervous system and Ca tends to accelerate the nervous system. The pertinence of this is: if a person tends to be “ramped up” most of the time (stressed out and wired), the last thing they should be taking is more Ca because it will only accelerate them even more. On the contrary, if a person tends to be very calm and collected in stressful situations, they need to be taking more Ca because, under stress, they need to be accelerated. Mg for a calm person can have devastating effects and Ca for a “wired” person can also be deleterious. So, with this explanation, taking Ca and or Mg for bone health is not just a black or white issue.
Let’s move on to the other main constituent of bone; protein. Bone is a type of dense connective tissue comprised of collagen, a fibrous protein. This protein comes from dietary intake of good quality foods that supply a broad spectrum of essential amino acids. These can be animal proteins like: grass-fed free-range beef, organic free-range chicken and eggs, and wild-caught cold water fish. Some examples of non-animal protein are: avocado and quinoa. Strict vegetarians need to be aware of the amino acid content of their foods so that correct combinations can be made to make a complete protein.
For this discussion, there are two major constituents of bone: protein and minerals.
Many of you are familiar with the disease Ricketts. Rickets is a softening of bones in children due to deficiency or impaired metabolism of vitamin D,magnesium, phosphorus or calcium; much like scurvy being a lack of vitamin C. Osteomalacia is the term used to describe a similar condition occurring in adults. The typical postural makeup of an individual with Ricketts is being “bow-legged”. Their bones get soft and bend; if bone gets soft, it doesn’t break easily. Treatment involves increasing dietary intake of calcium, phosphates and vitamin D. Exposure to ultraviolet B light (sunshine when the sun is highest in the sky) and cod liver oil, as stated earlier, are both good sources of vitamin D.
If D helps with Ca absorption, and a lack of D produces bones that bend, it is very difficult for bone to bend and break at the same time. In a nutshell, taking away the calcium from bone causes it to bend, not get brittle and break.
The other component of bone is protein. The minerals that comprise bone physiology are encased within a protein matrix. Removal of this protein matrix leaves minerals (Ca, Mg, Phosphorus, boron). In this situation, the bone will be comprised of a bunch of minerals (rock) and this creates bones that are brittle and break.
Osteoporosis is a condition of very low bone density. This low density is caused from a lack of dietary protein, NOT a lack of minerals.
…this is the abbreviated version.
George Bernard Shaw stated that, “All great truths begin as blasphemies”.