1. Caffeine Consumption and its Affect on Bone Density Mass
Naila Warren

2. Introduction
This video aims to explore how caffeine intake can effect bone mass density.
Caffeine naturally occurs in coffee, teas, and chocolate and is added to some drinks and foods.
High consumption of caffeine has been thought to negatively affect bone density mass that could lead to osteoporosis.

3. Bone Mass Density
Bone Mass Density or Bone Mineral Density (BMD) is the amount of bone mineral per volume of bone in bone tissue.
Osteoporosis is a condition in which bones have weakened and are more likely to fracture; this is due to age, health complications, and poor diet.

4. Hallström et. al. doi: 10.1186/1743-7075-7-12
Caffeine Studies
Coffee consumption and CYP1A2 genotype in relation to bone mineral density of the proximal femur in elderly men and women: a cohort study
Caffeine intake increases the rate of bone loss in elderly women and interacts with vitamin D receptor genotypes.
In a cohort study, conducted by Hallström et. al., 359 men and 358 women were given dietary guides that allowed variable intake of tea and coffee to follow for two years and then had the bone mass density (BMD)  of their proximal femur measured which is most vulnerable to osteoporosis.
Men who consumed 4 cups of coffee or more per day had 4% lower BMD at the total proximal femur as compared with men who drank 0-2 cups per day. This difference was not observed in female participants.1
In a cross sectional analysis conducted by Rapuri et. al. 443 women aged were asked to complete a 7 day food diary and BMD test of their lumbar spine, proximal femur, and total hip and a follow up was conducted 3 years later.
Caffeine intake of >300 mg/d was associated with a higher rate of bone loss in postmenopausal elderly women at most of sites studied and significantly at the spine.2
Hallström et. al. doi: /
Rapuri et. al. AJCN 2001;74(5):

5. PhramGKB Summary: Caffeine pathway3
Thorn et. al. doi: /FPC.0b013e d5e.

6. Caffeine Pathway
Caffeine is almost completely metabolized by cytochrome P4501A2 (CYP1A2).1
The Hallstrom et. al. study looked at whether the genotype’s rate to metabolize caffeine had any relation to BMD.
With higher CYP1A2 activity in men, caffeine will be more rapidly metabolized and the concentrations of metabolites like paraxanthine will become higher in relation to the concentration of caffeine.1
Paraxanthine, along with other derivatives of caffeine, are competitive antagonizers of the adenosine A1 and A2 receptors that are found in bone cells.

7. Conclusion
Consuming an average amount of caffeine (up to 400 mg/day)4 can be safe.
However high amounts of caffeine can have other adverse effects.
Some people may be more prone to BMD loss than others based of their genotypes.
A balanced diet containing foods high in calcium and vitamin D coupled with weight bearing exercises, starting as early as adolescents, can prevent osteoporosis.

8. References
1. Hallström H, Melhus H, Glynn A, Lind L, Syvänen A, Michaëlsson K. Coffee consumption and CYP1A2 genotype in relation to bone mineral density of the proximal femur in elderly men and women: A cohort study. Nutrition & Metabolism. 2010;7: site=eds-live&scope=site. Accessed October 31, doi: /
2. P B Rapuri, J C Gallagher, H K Kinyamu, K L Ryschon. Caffeine intake increases the rate of bone loss in elderly women and interacts with vitamin D receptor genotypes. The American journal of clinical nutrition. 2001;74(5):
3. Thorn C, Aklillu E, McDonagh E, Klein T, Altman R. PharmGKB summary: Caffeine pathway. Pharmacogenetics and Genomics. 2012;22(5): doi: /FPC.0b013e d5e.
4. Caffeine: How much is too much? Mayo Clinic. healthy-eating/in-depth/caffeine/art Published March 8, Accessed November 12, 2017.