Tea & Bone Health

Does supplement help?

Most people believe that taking calcium supplements will help mature people, particularly women after menopause, to fight against osteoporosis, the weakening of bone.

In May 2012, Europe rang an alarm. Such supplement could almost double the risks of heart attack.

This was one of the findings from EPIC, the European Prospective Investigation into Cancer and Nutrition₍₁₎, in which one of the cohort studies followed about 24,000 individuals for 11 years in Heidelberg concluded that those who took calcium supplements are 86% more likely to suffer from a heart attack than those who did not. For those who relied solely on supplements for their calcium intake, 2.7 times more₍₂₎.

Read about cardiovascular health and tea

Bone health: beyond supplements

Maybe this is not only an alarm for people who are faithful in using supplements, but also a wake up call for the Western medical idea of looking at health symptoms isolated from the wholeness of the body and its relationship with the changes of the season, the environment, and age.

This article is however, not about such morals. We have said too much about it already.

We want to share a few scientific studies about tea in relationship with bone health, an aspect where the public has been misinformed, if not under-informed.

Tea & Bone Health: Controversies

Some believe that habitual intake of caffeine weakens the bone. Certain medical professionals therefore advise people to stay away from coffee and tea.

In India, a major tea production and consumption country, there is a high prevalence of osteoporosis, particularly amongst women over 50. In a study on the related topic₍₃₎, Indian scientists concluded that people who drink more tea are more prone to hip fracture , a common problem in patients with osteoporosis.

However, studies in other countries have different conclusions.

Change of bone mineral density in older women ( mg/cm² ) from the Australian study
The less change means the bone stays stronger. As to what “neck”, “trochanter” etc mean, please refer to the diagram of the femur below.
Data source: A Devine et al, Tea drinking is associated with benefits on bone density in older women, American Journal of Clinical Nutrition 2007; 86:1243–7

For example, one involving 1500 women between 70~85 yrs in Australia for four years concludes that people who drink tea are able to hold on to their bone density 2.5 times better than non-tea-drinkers₍₄₎. They have observed irregularities in other studies and suspect the quality of tea could be one reason.

The hero again: green tea catechins

Actually many other scientists agree. They have found that green tea, in particular its polyphenols, promotes bone formation₍₅₎ and protects it from disintegration₍₆₎.

Structure of the upper part femur — where the thigh bone joins the pelvis — and common occurrence of hip fracture

A detail study₍₇₎ in Hong Kong on the mechanism in which how tea catechins promotes bone health not only confirms the biochemical actions in facilitating bone formation and suppressing bone disintegration, but also finds that there is a reverse relationship between the fatty content in our bone marrows and the density of our bones.

As we get older, there is a tendency for an increase of fats in the marrows and a decrease in bone density. They have found out that tea catechins help to decrease the fats in the marrows and the rate of loss in bone density.

It is the quality that counts

It seems to point to the fact that then, green tea is the one for bone health, and black tea, as that drunk in India, does not. That is NOT a conclusion. The study in Australia, as we pointed out earlier, where they found that people who drink more tea had better bone health, was done on people who drank tea in general, including black tea. continues to page 2

footnotes

1. EPIC is a large study of diet and health having recruited over half a million (520,000) people in ten European countries: Denmark, France, Germany, Greece, Italy, The Netherlands, Norway, Spain, Sweden and the United Kingdom. Funded by The European Commission and coordinated by WHO. Official website: http://epic.iarc.fr/index.php

2. Calcium supplements ‘double risk of heart attack’ by D Campbell, The Guardian, Thursday 24 May 2012;
If you have been taking calcium supplement as a prescription, however, it is advisable to talk to your physician for an evaluation of your individual condition. 

3. R Jha et al, Pilot case-control investigation of risk factors for hip fractures in the urban Indian population, BMC Musculoskeletal Disorders 2010, 11:49

4. A Devine et al, Tea drinking is associated with benefits on bone density in older women, American Journal of Clinical Nutrition 2007; 86:1243–7

5. N Holzer et al, Green tea protects human osteoblasts from cigarette smoke-induced injury: possible clinical implication, Langenbeck’s Archives of Surgery, March 2012, 397(3):467-74

6. M Kamon et al, Green tea polyphenol epigallocatechin gallate suppressed the differentiation of murine osteoblastic MC3T3-E1 cells, Cell Biology International, December 2009, 16;34(1):109-16;
T Tominari et al, Epigallocatechin gallate (EGCG) suppresses lipopolysaccharide-induced inflammatory bone resorption, and protects against alveolar bone loss in mice, FEBS OpenBio, June 4 2015

7. C Ko et al, Pro-bone and Antifat Effects of Green Tea and Its Polyphenol, Epigallocatechin, in Rat Mesenchymal Stem Cells in Vitro, Journal of Agricultural and Food Chemistry, 2011, 59, 9870–9876