Smoothies can have a surprisingly high sugar content.
New research, published in the online journal BMJ Open, describes the sugar content of fruit drinks, natural juices and smoothies, in particular, as "unacceptably high."
According to Yale Health, the average American consumes around 22 tsps of added sugar every day; for teens, the figure is closer to 34. One 12-oz can of soda contains 10 tsps of sugar.
The American Heart Association (AHA) recommend no more than 3-4 tsps of sugar a day for children, and 5 tsps for teens.
In the UK, guidelines recommend a maximum of 19 g, or just under 4 tsps for children aged 4-6 years, and 24 g at age 7-10 years, or just under 5 tsps, according to the UK's National Health Service (NHS).
As awareness spreads about the impact of sweetened drinks on weight gain and tooth decay, many people are turning to fruit juices and smoothies as healthy alternatives to sodas, iced tea and other favorites.
Even 100% juice is not guilt-free
However, even 100% fruit juice is not as innocent as it seems. The American Academy of Pediatrics (AAP) recommend not giving juice to infants under 6 months, and children aged 1-6 should have no more than 4-6 oz, or one half to three quarters of a cup. The recommended amount for 7-18 year-olds is 8-12 oz, or 1-2 cups.
Researchers from the University of Liverpool and the University of London in the UK assessed the sugar content per 100 ml (approximately 3.5 oz) of fruit juice drinks, 100% natural juices, and smoothies aimed at children, using information from the pack label.
They checked the amount of "free" sugars in 203 standard portion sizes (200 ml, or around 7 oz) of UK-branded and store-brand products.
Free sugars include glucose, fructose, sucrose and table sugar, which are added by the producer, as well as naturally occurring sugars in honey, syrups, fruit juices and fruit juice concentrates. Although fructose occurs naturally in fruit, when consumed as a drink, it can cause dental caries - as can any other sugar.
There are other naturally occurring sugars in whole fruits and vegetables, which the body metabolizes differently, and they act to curb energy intake. These were not included.
Over 40% of drinks contain 4 tsps of sugar
The sugar content in the drinks surveyed ranged from 0-16 g/100 ml, and the average was 7 g/100 ml, or around 1.5 tsps. It was significantly higher in pure fruit juices and smoothies.
The average sugar content of the 21 pure fruit juices assessed in the survey was as high as 10.7 g/100 ml or just over 2 tsps, and in the 24 smoothies, it was up to 13 g/100 ml, or just over 2.5 tsps. Over 40% of all the products, contained 19 g, or around 4 tsps, of free sugars, the maximum daily amount recommended for children.
Around 78 products contained zero-calorie sweeteners, such as aspartame. While classed as safe, health experts say they are not helping children's taste buds to get used to a less sweet diet.
Based on the findings, the team recommends:
- Not counting fruit juices, juice drinks and smoothies with a high free sugar content as one of the "5 a day"
- Consuming fruit whole, not as juice
- Diluting fruit juice with water or opting for unsweetened juices, and allowing these only during meals
- Limiting intake to 150 ml/day, or just over 5 oz
- Requiring manufacturers to stop adding unnecessary sugars to fruit drinks, juices and smoothies, if necessary, through government intervention.
Medical News Today asked Dr. Simon Capewell, who led the research, whether, in the light of these findings, we should reduce our fruit intake, too.
He told us:
"No. Fruit is very good for the health. Vegetables likewise. Indeed, we would recommend unlimited fruit and vegetables."
Whole fruit has a higher fiber content than juice, it takes longer to consume, it is more satisfying, and there is evidence that the body metabolizes whole fruit in a different way, adjusting its energy intake more appropriately than it does after drinking juice.
A limitation of the study was that researchers only looked at products that are available in supermarkets, and there may be alternatives with a lower sugar content.
MNT recently reported on research suggesting that health warnings on sugary drinks could encourage parents to think twice about getting them for their children.