Experts recommend reducing the intake of added (“free”) sugars to around six teaspoons a day and limiting sugary drinks to less than one serving a week after a comprehensive review of the evidence published by the BMJ today .
They found significant harmful associations between sugar consumption and 45 outcomes, including asthma, diabetes, obesity, heart disease, depression, certain cancers and death.
It is well known that excessive sugar consumption can have negative health effects, prompting the World Health Organization (WHO) and others to suggest reducing the consumption of free or added sugars in less than 10% of total daily energy intake.
But before developing detailed sugar restriction policies, the quality of the existing evidence needs to be comprehensively assessed.
Researchers based in China and the United States therefore carried out a global review to assess the quality of evidence, potential biases and validity of all available studies on dietary sugar consumption and health outcomes.
Umbrella reviews synthesize previous meta-analyses and provide a high-level summary of research on a particular topic.
The review included 73 meta-analyses (67 of observational studies and six of randomized controlled trials) of 8601 articles covering 83 health outcomes in adults and children.
The researchers assessed the methodological quality of the included articles and graded the evidence for each outcome as high, moderate, low or very low quality to draw conclusions.
Significant harmful associations were found between dietary sugar consumption and 18 endocrine or metabolic outcomes, including diabetes, gout, and obesity; 10 cardiovascular outcomes, including high blood pressure, heart attack, and stroke; seven cancer outcomes, including breast, prostate and pancreatic cancer; and 10 other outcomes, including asthma, tooth decay, depression, and death.
Moderate-quality evidence suggested that consumption of sugar-sweetened beverages was significantly associated with increased body weight for highest versus lowest intake, while added sugar intake versus no sugar intake Added sugar was associated with increased fat accumulation in liver and muscle.
Low-quality evidence indicated that each 1 serving per week increase in sugar-sweetened beverage consumption was associated with a 4% higher risk of gout, and each 250 ml/day increase in sugar-sweetened beverage consumption was associated with a risk of 17% and 4% higher. coronary heart disease and death, respectively.
Low-quality evidence also suggested that every 25 g/day increase in fructose intake was associated with a 22% increased risk of pancreatic cancer.
In general, no reliable evidence has shown beneficial associations between dietary sugar intake and health outcomes, with the exception of glioma brain tumors, total cholesterol, type 2 diabetes, and mortality. by cardiovascular disease. However, the researchers say that these favorable associations are not supported by strong evidence and that these results should be interpreted with caution.
The researchers acknowledge that the existing evidence is mostly observational and of low quality, and stress that the evidence for an association between dietary sugar consumption and cancer remains limited but warrants further research.
Nevertheless, they say that these results, combined with advice from the WHO, the World Cancer Research Fund and the American Institute for Cancer Research, suggest reducing the consumption of free sugars or added sugars to less of 25 g/day (about six teaspoons per day) and to limit consumption. of sugary drinks to less than one serving per week (approximately 200 to 355 ml/week).
To change sugar consumption habits, especially for children and adolescents, a combination of education and widespread public health policies around the world is also urgently needed, they add.
Source:
Journal reference:
Huang, Y. et al. (2023). Dietary sugar consumption and health: an umbrella review. BMJ. doi.org/10.1136/bmj-2022-071609.
