Soft drink and our health

Why we love it and why we need to stop drinking it. By Kirsten Braun

glass of cola softdrink with a straw

Australians love their sweet, fizzy drinks. We are one of the top 10 consumers of soft drinks per capita in the world. Last year, Australians consumed 447 million litres of regular cola drinks alone. If we include all sugar-sweetened beverages, such as cordials, soft drinks, flavoured mineral waters, energy drinks and fruit and vegetable drinks with added sugar, the amount escalates to 1.28 billion litres. 

The United Kingdom recently announced they will introduce a tax on soft drinks in 2018 to target childhood obesity. In Mexico, a similar tax introduced in 2014, saw a 12 per cent drop in sales of taxed drinks. Without any plans in Australia to introduce a soft drink tax in the near future, we need to rely on educating people about the negative health impacts of soft drinks. Here are the top six health reasons why we need to reduce our consumption of soft drinks.

1. Obesity

Regular soft drinks contain high amounts of sugar. For example, a 375 ml can of cola contains around 10 teaspoons of sugar. This climbs to 16 teaspoons in a 600 ml bottle. Both amounts exceed the World Health Organization’s recommendation of 6 teaspoons of sugar a day. Soft drinks are a significant contributor to a person’s total energy intake. It appears that when people drink them, they generally do not compensate by reducing their intake of food. Therefore, the kilojoules consumed from soft drinks are add-on kilojoules and contribute to an increase in weight and obesity. Obesity is a risk factor for many conditions including some cancers, cardiovascular disease and Type 2 diabetes.

2. Diabetes

The Nurses’ Health Study included over 50,000 women and examined sugar sweetened beverage (SSB) consumption and diabetes risk. The study found that women who consumed one or more SSB a day had a 83% greater risk of developing Type 2 diabetes over the course of eight years compared to those women who consumed less than one SSB a month.

3. Increased appetite

Studies indicate the increase in kilojoules associated with drinking soft drinks is higher than what can be accounted for by the soft drinks alone. It appears that consuming soft drinks might actually stimulate the appetite and/or stop people from feeling full, resulting in people eating more. One study found that people given soft drinks consumed 17% more energy than in their typical diet, even after taking into account the extra energy from the soft drinks.

4. Less calcium-rich drinks

When we consume soft drinks it often means that they replace the consumption of calcium-rich drinks such as milk. This is a particular concern for young people who are building their peak bone mass. To achieve the maximum peak bone mass, people need to consume adequate amounts of calcium each day.

5. Bone strength

It appears that drinking cola, but not other soft drinks, is linked to lower bone mineral density (BMD) in women. A lower BMD places women at risk of osteoporosis. Cola contains phosphoric acid, which can leach calcium out of the bone. Cola may also contribute to a lower BMD if women are drinking cola instead of calcium-rich drinks such as milk (see section above). 

6. Tooth decay

Soft drinks affect the teeth in two main ways. The high amount of sugar in soft drinks contributes to teeth decay. In addition, soft drinks, including diet varieties, have high levels of acid in them which weaken the tooth enamel causing cavities. Cola, for example, was found to be 10 times more erosive than fruit juice. 

What about diet soft drinks?

While diet soft drinks may not contain the kilojoules of sugar, the various artificial sweeteners used in these beverages have their own unhealthy traits. Research has shown that drinking diet soft drink increases a person’s risk of metabolic syndrome, Type 2 diabetes and cardiovascular disease. It is thought that diet soft drinks might interfere with a person’s metabolism and/or insulin levels. Similarly, people who drink diet soft drink might eat more junk food as they feel diet soft drink allows them to eat more of these types of food. Diet soft drinks also taste intensely sweet, which can increase a person’s preference for other sweet foods or drinks. The acid they contain causes teeth erosion in the same way as regular soft drinks (see Tooth decay section). In addition, as people tend to drink larger quantities of diet soft drink than regular soft drink their teeth are exposed more regularly to the acidic effects of the soft drink.

Last updated: September 2016

©Women's Health Queensland Wide Inc. This article was written by Kirsten Braun and reviewed by the Women's Health Queensland Wide editorial committee. It was published in Health Journey 2016 Issue 3.


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