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Consuming over 6 teaspoons of added sugar a day linked to stroke, depression, asthma

Sugar cubes against a dark background
Consuming too much natural or added sugar is associated with negative health outcomes. HUIZENG HU/Getty Images
  • Sugar occurs naturally in foods but can also be added during manufacturing or cooking. 
  • Researchers are still working to understand the dangers of consuming too much sugar. 
  • A​ recent umbrella review found that sugar consumption is associated with several poor health outcomes, including cardiovascular problems and several types of cancer. 
  • People can take steps to limit their intake of added sugars and sugar-sweetened beverages. 

Proper nutrition is about meeting the body’s needs. This involves careful balance and not getting too much or too little of any one nutrient. Sugar is a dietary component, but consuming too much sugar can contribute to poor health outcomes. 

A​ recent umbrella review Trusted Source BMJ Peer reviewed journal Go to source  published in The BMJ Trusted Source BMJ Peer reviewed journal Go to source  found that dietary sugar intake was associated with several adverse health outcomes, including weight gain, gout, type 2 diabetes, cardiovascular disease, and certain cancer types. However, the strength of the evidence varied. 

Based on these findings, review authors suggest that people should work to keep their amount of added sugars to six teaspoons a day or less and only consume one or fewer sugar-sweetened beverages a week. 

Natural sugars and added sugars

Dietary sugar is a broad term for a few carbohydrate types. For example, glucose, fructose, and lactose are all types of sugar. Some sugar Trusted Source American Heart Association Highly respected national organization Go to source  occurs naturally in foods like milk or fruit, so people will get this sugar by consuming these foods. 

Added sugar is any sugar that manufacturers or consumers add to foods. Based on this distinction, groups like offer recommendations for limiting the intake of added sugars. 

The body requires some sugar, so people cannot eliminate it entirely from their diets, but the source is essential. Molly Kimball, a registered dietitian and nutrition journalist, who was not involved in the study, explained to Medical News Today:

“Glucose is a primary source of fuel for our bodies: the brain, central nervous system and muscles. Every cell in your body needs glucose to survive…But we don’t need to incorporate added sugars (such as sucrose or glucose) [into] our diets, as many foods, such as proteins and carbohydrate-containing foods like vegetables and whole grains can be naturally converted into glucose by our bodies.”

Researchers are still reviewing the evidence to make the best possible recommendations for sugar consumption. 

How dietary sugar affects health

This umbrella review included 73 meta-analyses and, ultimately, over 8,500 articles. The review authors wanted to examine how dietary sugar consumption impacted health outcomes. One specific area of interest was the consumption of sugar-sweetened beverages, which can be a significant source of added sugar. 

Review authors found several harmful associations between sugar consumption and poor health outcomes. Their research included the following highlights:

T​hey also found a few other harmful associations between sugar consumption and 45 health conditions, including depression, dental problems, and asthma in children. 

Researchers noted that the evidence associating sugar consumption with cancer is still limited, and this area warrants further investigation. In addition, the quality of evidence for the associations found varied. 

Dr. Felix Spiegel, a bariatric surgeon at Memorial Hermann in Houston, Texas, who was also not involved in the study, noted to MNT

“The reviews findings are very impressive and convincing. Excess sugar intake greatly increases metabolic disease such as diabetes, cancer risk, heart disease, psychological disorders, and tooth problems.” 

Based on the data from the study, review authors suggest a further reduction of added sugars and sugar-sweetened beverages from one’s diet. Eva De Angelis, a health and nutrition writer and licensed dietitian nutritionist, who was not involved in the study, explained these recommendations: 

“We’re all aware that all health organizations worldwide, including the World Health Organization, encourages people to reduce their intake of free/added sugars to less than 10% of their total daily energy intake. This roughly translates to about 50 grams or 12 teaspoons of sugar daily for adults and adolescents.”

“[T]he researchers recommend further reduction of sugar intake to less than 25 grams per day or about six teaspoons, and no more than 355 ml of sugar-sweetened drinks weekly to prevent as much as possible the many negative health outcomes identified.”
— Eva De Angelis

Study limitations

T​his review did have several limitations. First, researchers acknowledge that there was the risk of some publication bias. Second, researchers were limited by the same limits of the studies they examined and the differences between the studies. For example, studies used different methods to examine sugar intake, many of which carry a particular risk of error in data collection. Studies also measured sugar consumption differently. 

Reviewers could not evaluate the sugar intake in some foods. The authors further note the importance of examining the potential for many confounding factors when interpreting outcomes and conclusions. 

Some analyses included had a conflict of interest because of funding, so their results should be interpreted cautiously. Finally, the current reviewers did not look at the competing interests of the individual studies from the meta-analyses they reviewed. 

How to decrease your sugar consumption

People can take steps to limit their consumption of added sugars, seeking appropriate guidance from doctors and other professionals. While individual needs differ, the results from this study suggest that limiting added sugars could help protect against certain adverse health outcomes. 

Dr. Spiegel offered the following advice for the reduction of sugar consumption:

“Steps to limit consumption include reading labels and making sure there’s no hidden sugar. Also, avoiding packaged foods is very helpful. Eating fruits as a substitute is also very helpful as well. Meat, fish and poultry should be simply grilled or air fried without adding dressing or glaze. Use lots of natural spices instead. Drinking mostly water is also helpful. Avoiding alcoholic drinks that are sweet can help prevent excessive sugar intake.”

“Fruits, vegetables, whole grains, and lean proteins will all provide the natural glucose needed to sustain a healthy body. When you do eat packaged foods, read the nutritional labels and understand how certain foods add to your daily sugar intake,” Molly Kimball, registered dietitian, who was not involved in the research, further noted.

This article originally appeared on Medical News Today.

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