I started this week thinking I had all of the time in the world to write more blogs… the presentation power point took me a bit longer than expected (along with have to work more than I’m used to), but it’s looking good now :)! Just have to practise so I don’t embarrass myself in front of the 75 or so grade 12s lol… this should be a good learning experience!
Here’s a picture of me at a comp. last year
And as per request, here’s a picture of the Christmas tree I made :p lol
Osteoporosis is characterised by low bone mass, fragility and an increased risk for fractures. It’s estimated that one in three women and one in twelve men will suffer from osteoporosis! Menopause (as well as amenorrhea) put women at a higher risk for osteoporosis. Many of us stay unaware of the rise in osteoporosis and that’s why this post will be about bone health! Hope you enjoy :).
Bone is a living tissue with continuous cycles of bone formation (via osteocytes and osteoblasts) and breakdown (via osteoclasts). Our bone health in adulthood is primarily determined by: the maximum peak bone mass which is achieved during development to early adulthood, maintaining bone mass and by a reduction in the rate of bone loss in adulthood. Both peak bone mass and the rate of bone loss are determined by a number of factors that include genetics, exercise and nutrition.
So what do we need to keep healthy bones?
Calcium is the most abundant mineral in our bodies; 99% of that calcium resides in our bones and teeth. The other 1% is located in our body fluids and soft tissues. Calcium plays a role in both support and metabolic function, it is essential for e.g. cell structure, signal transmissions, contractions, nerve functions, blood clotting, enzyme activity, etc. The metabolic role of calcium (blood calcium) is much more important to our general health and functioning, because of this; blood calcium needs to be tightly maintained at 90-105mg/L. When we do not absorb enough calcium to fulfil the 90-105mg/L requirements in our blood, bone can be broken down in order to supply our blood with calcium.
Vitamin D (1,25-dihydroxycholecalciferol) is required to stimulate the absorption of calcium across our intestine (by inducing Ca-binding proteins). Vitamin D is mainly derived from sunlight but recent research has indicated that this source may not be adequate, especially in the winter. Vitamin D stimulates bone formation and, along with the parathyroid hormone, regulates calcium (and phosphorus) metabolism by promoting calcium absorption by our intestine and kidneys. There is a lot of evidence showing that even a mild vitamin D deficiency (especially in females and children) can lead to detrimental bone health effects. Vitamin D is clearly a very important consideration in terms of bone health and calcium absorption.
And now onto a less known vitamin in regards to bone health…
Vitamin K (‘koagulation vitamin’) was first described for its coagulating properties. Phylloquinone (K1) is derived from plants and menaquinone (K2) is derived from bacteria. In respect to bone health, vitamin k is a cofactor in several bone protein carboxylations (including osteocalcin). When our vitamin K consumption is not adequate, the result may be an under-carboxylation of osteocalcin which may ultimately result in a lower bone mass and higher risk for osteoporosis.
On a related note, vascular calcification happens when calcium builds up in our vessels (associated with atherosclerosis). Vitamin K has been proposed to prevent this vascular calcification because it activates the matrix GLA protein (MGP) which inhibits calcification in vascular tissue. Animal and cell studies support this idea but human studies are pretty inconsistent. The majority of human studies have relied on K1, yet growing evidence indicates that higher K2 (and not K1) is associated with less calcification (which may be the cause of inconsistencies in human studies). Without K2, we may not be able to move calcium out of our soft tissues (vessels) to our bones, ultimately leading to both osteoporosis and atherosclerosis. Consequently, calcium supplementation may actually lead to osteoporosis and atherosclerosis if there is a vitamin k (2?) deficiency. If looking to supplement, a good option would be a supplement that includes vitamin k2. This is a very new and controversial area of research.
A few other nutrients have gained more research indicating their importance in bone health including magnesium, silicon and boron. Magnesium can be found in e.g. potato skins and lentils, silicon can be found in e.g. carrots and green beans and finally boron can be found in e.g. prunes.
I’ll leave it at that… Take care of your bones! You’ll be happy you did 20 or so years down the road :).
Price C, Langford J, and Liporace F. (2012) Essential Nutrients for Bone Health and a Review of their Availability in the Average North American Diet. Open Orthop J.; 6: 143–149.
Eastell R (1999) Pathogenesis of postmenopausal osteoporosis. In Primer on the Metabolic Bone Diseases and Disorders of Mineral Metabolism, 4th ed., pp. 260–262.
Consensus Development Conference (1991) Diagnosis, prophylaxis and treatment of osteoporosis. Am J Med 90, 107–110.
van Staa TP, Dennison EM, Leufkens HG & Cooper C (2001) Epidemiology of fractures in England and Wales. Bone 29, 517–522.
Abrams SA (2003) Normal acquisition and loss of bone mass. Horm Res 60, 71–76.
Smith R (2003) Calcium and the bone minerals. In Human Nutrition and Dietetics, pp. 451–489.
Parfitt AM (1990) Osteomalacia and related disorders. In Metabolic Bone Disease and Clinically Related Disorders, 2nd ed., pp. 329–396.
Underwood JL & DeLuca HF (1984) Vitamin D is not directly necessary for bone growth and bone mineralization. Am J Physiol Endocrinol Metab 246, E492–E498.
Lehtonen-Veromaa MK, Mottonen TT, Nuotio IO, Irjala KMA,
Leino AE & Viikari JSA (2002) Vitamin D and attainment of peak bone mass among peripubertal Finnish girls: a 3-y prospective study. Am J Clin Nutr 76, 1446–1453.
Chapuy MC, Arlot ME, Duboeuf F, Brun J, Crouzet B, Arnaud S,
Delmas PD & Meunier PJ (1992) Vitamin D and calcium to prevent hip fractures in elderly women. N Engl J Med 327, 1637–1642.
Szulc P, Chapuy M-C, Meunier PJ & Delmas PD (1996) Serum undercarboxylated osteocalcin is a marker of the risk of hip fracture: a three year follow up study. Bone 18, 487–488.
Weber P (2001) Vitamin K and bone health. Nutrition 17, 880–887.
Shea MK, and Holden RM. (2012) Vitamin K status and vascular calcification: evidence from observational and clinical studies. Adv Nutr.;3(2):158-65. doi: 10.3945/an.111.001644.