SSBs such as soft drinks, energy drinks or coffee and tea with added sugars are typically associated with increased risk of obesity, diabetes, dental caries and cardiovascular diseases.
However, studies on SSB effect on bone health is limited, particularly because it takes a long time to determine the effects on bone health. Sugar, acid and caffeine present in SSBs may affect bone metabolism by disturbing calcium absorption and homeostasis in the body and increasing calcium excretion through urine.
To date, there is only one systematic review studying SSB consumption and childhood fracture.
“This review is, to the best of our knowledge, the first systematic review and meta-analysis to evaluate the association between SSBs consumption and bone health in children and adults,” researchers from Kyung Hee University in South Korea wrote in Nutrition.
This study included 26 publications from several databases comprising a total of 124,691 healthy participants without medical conditions or treatments affecting bone metabolism.
Participants were aged four to 98, with studies conducted across Europe, US, South Korea, Egypt, UK, Saudi Arabia, Australia, Canada, Chile, China and New Zealand.
SSBs were defined as carbonated, soda or soft beverages or coffee with sugar/syrup.
The results from this meta-analysis showed a significant inverse association between SSBs intake and BMD in adults, meaning a higher consumption was associated to lower BMD.
This association was found to be of a moderate effect in females, but not in males, suggesting that excessive SSBs consumption is more detrimental to female bone health than male bone health.
Researchers said this may be because women tend to have smaller bones and lower bone strength as well as younger onset of bone loss than men, which makes them more susceptible to osteoporosis.
There was a moderate or large effect on BMD in individuals aged under 30 years, but no association with BMD in participants older than 50 years of age.
According to researchers, bone mass increases rapidly during childhood and adolescence, and up to 90% of peak bone mass accrues during this time. However, this is also the period of high SSB intake, which is usually accompanied by a decrease in calcium and milk intake.
“These eating habits may make it difficult to acquire adequate bone mass or achieve peak bone mass, thereby increasing the risk of age-related osteoporosis in the future as well as increasing the risk of bone fractures in children,” researchers said.
Therefore, efforts to control children’s excessive intake of SSBs and to encourage healthy eating habits are important for maintaining healthy bone health and improving quality of life later in life.
Sugar, acid and caffeine
The findings also revealed that a high consumption of carbonated beverages had a moderate effect on BMD, but consumption of coffee with sugar showed no association with BMD.
In SSBs, the main sweeteners are typically high-fructose corn syrup, or glucose-fructose syrup which when consumed in excessive amounts, could lead to renal dysfunction and mineral imbalances, which could adversely affect bone health.
Acids such as phosphoric acid are also typically added into SSBs to provide a tangy taste. However high levels of phosphoric acid affects calcium metabolism negatively, which when combined with low dietary calcium intake, could increase the risk of developing bone diseases.
The low pH of carbonated drink such as cola (pH 1.8) can cause a sudden change in the gastric pH and interrupt calcium absorption, impairing bone health.
Caffeine is another potential risk factor, although its role in bone loss is controversial. Caffeinated beverage consumption, such as soda and sugary coffee, have been linked to reduced bone density and increased fracture rate.
Encourage balanced diet
Dietary calcium from sources such as milk is the most important dietary factor for bone metabolism and bone health.
However, researchers said there was a trend towards replacing milk with cola and other soft drinks, which results in a low calcium intake, inversely affecting bone health.
“This review enabled us to confirm the relationship between high SSBs consumption and insufficient intake of milk and calcium,” they added.
One limitation of this study was the use of different food intake methods such as food records, 24-h dietary recall, FFQ, or dietary history.
“While all of which are proven to be valid as common methods in food intake survey research, the inconsistencies in the methods are inevitable in this kind of study.”
Despite this, the findings show a significant inverse association between consumption of SSBs and BMD, and worldwide efforts must be done to reduce excessive consumption of SSBs to reduce rates of non-communicable diseases as well.
“Sugar-sweetened beverage consumption and bone health: a systematic review and meta-analysis”
Authors: Hyejin Ahn & Yoo Kyoung Park