Calcium intake in Asia's populous countries barely hitting half the recommended daily intake
Other Asian countries have similarly low calcium intake, ranging from 175mg/day to 500mg/day.
Calcium intake of 74 countries is available on an interactive online global map launched by the International Osteoporosis Foundation (IOF) with data taken from a study published in Osteoporosis International.
The purpose of the map is “to get estimates of calcium intake in different parts of the world…with the results, we will identify places where intake is lowest and use that as a platform to help promote change,” said Professor Bess Dawson-Hughes, chair of the IOF Calcium Steering Committee.
According to the map, South America fared slightly better than Asia, with calcium intake ranging from 400 to 600 mg/day.
Northern European countries performed best, with Iceland, Ireland and Germany exceeding the recommended daily intake.
Interestingly, there is stark variation in calcium intake for countries within the same region. For instance, average intake in Colombia in 297mg/day, while Mexico is as high as 805 mg/day.
However, the study “did not find any consistent differences between sexes, age group, rural and urban populations in their calcium intake,” said the study’s lead author Ethan Balk, an associate professor at the Centre for Evidence Synthesis in Health in the Brown University School of Public Health.
Calcium accounts for 30% to 35% of bone mass, as such, low calcium intake may adversely affect the retention of bone mass in older adults.
More hip fractures
Hip fracture is projected to increase from 1.66 million in 1990 to 6.26 million by 2050, with China and South America accounting for majority of the cases, said the study.
In China, incidences of hip fracture in elderly aged 70 and above were already on the rise since 20 years ago. During 1990 to1992 and 2002 to 2006, number of hip fractures increased more than threefold in women and twofold in men.
Although hip fracture could be caused by dietary, lifestyle, and genetic factors, inadequate calcium intake appears to amplify the rate of incidence.
Links with vitamin D
According to the study, low calcium intake corresponds with a low level of vitamin D.
The link is notable in China, Malaysia, India, and South Korea where serum 25(OH) D levels are generally in the suboptimal range of 25–49 ng/Ml.
Vitamin D plays a role in building and maintaining healthy bones. Inadequate amount can have a negative impact on peak bone mass.
As such, low calcium intake and low 25(OH) D levels is of particular concern, as it is known to increase the risk of osteoporosis.
Limitations
The study on calcium intake was based on literature review of existing surveys.
However, out of the 74 countries, only 18 had current (since year 2000) estimates of dietary calcium intake and are nationally representative.
Furthermore, different surveys used different methodologies, ranging from food frequency questionnaires, recall to diet records.
Hence, the study acknowledged that “judgements had to be made regarding whether specific studies or literature were less representative than others; for example, whether to choose older, larger studies or newer, smaller studies with a broader eligible age range.”
Source: Osteoporosis International
“Global dietary calcium intake among adults: a systematic review”
https://doi.org/10.1007/s00198-017-4230-x
Authors: E.M Balk, et al.
