Sugars, Sweeteners & T2DM: The Bad, the Bad & the Ugly

In July 2015, the U.S. Food and Drug Administration (FDA) proposed the inclusion of “added sugars” to the percent daily value (%DV) on the Nutrition Facts label for packaged foods. Under the new proposal, “added sugars” would appear indented and below the “sugars” category that already appears on the label.

The decision comes after a review of recent scientific evidence by the 2015 Dietary Guidelines Advisory Committee showing that meeting daily nutrient needs can be difficult if added sugars exceed 10% of total daily calories. The committee also recommended that Americans cut down on empty calories and reduce their added sugar intake to fewer than 10% of daily calories. Currently, Americans obtain about 16% of their daily calories from sugars.¹ To put that into perspective, a 20-ounce bottle of Coca-Cola contains about 16 teaspoons of added sugar, or 130% of the recommended daily intake.²

The Institute of Medicine, American Heart Association, American Academy of Pediatrics, and the World Health Organization have also warned about the dangers of added sugars.

The FDA estimates that relabeling will cost about $2.3 billion, but cumulative benefits over 20 years could range from $21.1 billion to $31.4 billion.³

The FDA proposal comes amid accumulating evidence suggesting that what you eat, rather than how much, plays a role in the development of chronic illnesses like diabetes and cardiovascular disease. For years, researchers had said that the main problem concerns the sheer number of calories consumed, as well as resulting obesity. Research now shows that the amount of empty calories-especially calories from added sugars-can contribute to the development of diabetes.

For example, a recent study that evaluated ten years of data on diabetes and nutritional food components in 175 countries has pointed to a direct, independent association between added sugars and diabetes. Results showed that increasing sugar intake by about one can of soda per day increased diabetes prevalence by 1.1% (P<0.001). The relationship remained even after adjusting for obesity, total calories, aging, income, sedentary behavior, alcohol use, and several other related factors.⁴

A recent meta-analysis also looked at just this issue. It included 21 studies conducted in the US and UK, published through February 2014, and covering over 38,000 cases of incident T2DM. Results suggested that 11% of T2DM cases predicted to develop over 10 years in the US could be attributed directly to consuming sugar-sweetened beverages.⁵ Other types of beverages may not necessarily be safe, either.  Results also showed that increasing consumption by one serving/day increased the incidence of T2DM by 13% for sugar-sweetened beverages, by 8% for artificially sweetened beverages, and by 7% for fruit juices, after adjusting for obesity.⁵

Teasing out the role of artificial sweeteners in the development of metabolic disease, though, poses a tricky research question. That’s because those at risk for metabolic disease or who are trying to lose weight may switch to artificially sweetened foods as a way to reduce sugar or calorie intake, which muddies the data.

One study in the UK aimed at clearing up this dilemma. The study included over 25,000 people who were free of diabetes at the start of the study. Researchers estimated sugary beverage consumption from participant-reported 7-day food diaries, and followed participants for over 10 years.

Results showed that consumption of artificially sweetened beverages increased the risk of T2DM by 22% (HR 1.22 [1.11, 1.33]), which was similar to the 21% increased risk of T2DM found with soft drinks (HR 1.21 [1.05, 1.39]). After adjusting for obesity, though, the association between artificially sweetened beverages and T2DM weakened (HR 1.06 [0.93, 1.20]). Further analyses showed that substituting artificially sweetened beverages for any type of sugar sweetened beverage failed to decrease the incidence of T2DM. This remained true even after adjusting for calorie intake and obesity.

Estimates showed that drinking one serving per day of water or unsweetened tea or coffee instead of sugar-sweetened beverages could decrease the incidence of T2DM by 14%-25%.⁶

Research, mostly from animal studies, provides some evidence that artificial sweeteners may be metabolically active, increasing the risk of obesity, metabolic syndrome, and T2DM in and of themselves.

One explanation, based on rodent models, could be that artificial sweeteners interfere with learned responses to sweet foods. Upon ingestion of artificial sweeteners, the body senses the sweetness and gets ready to digest calories. The difference between anticipated and actual calories tricks the body,  interfering with the glucoregulatory response controlling energy homeostasis.⁷ A second explanation holds that artificial sweeteners interfere with the gut microbiome, which contributes to glucose intolerance.⁷ One study exposed seven healthy human volunteers who did not usually eat artificial sweeteners to one week of the FDA maximum acceptable saccharin intake. Results showed that regular saccharin exposure in most participants increased glycemic responses to glucose load, as measured on oral glucose tolerance tests. Stool transplant from humans with altered glycemic responses to saccharin induced glucose intolerance in mice.⁸ A third theory holds that artificial sweeteners could interact with sweet-taste receptors expressed not just in the mouth but throughout the digestive system. This interaction could be detrimental to regulation of glucose absorption from the gut, and could also trigger insulin secretion.⁷

[[{"type":"media","view_mode":"media_crop","fid":"42785","attributes":{"alt":"© Efired/Shutterstock.com","class":"media-image media-image-right","id":"media_crop_3034142716958","media_crop_h":"0","media_crop_image_style":"-1","media_crop_instance":"4652","media_crop_rotate":"0","media_crop_scale_h":"0","media_crop_scale_w":"0","media_crop_w":"0","media_crop_x":"0","media_crop_y":"0","style":"width: 150px; height: 189px; float: right;","title":"© Efired/Shutterstock.com","typeof":"foaf:Image"}}]]Imitating nature can have its drawbacks. Sometimes the solution lies in the commonplace, like a simple glass of water.

• The FDA has proposed to include added sugars on the %DV label for packaged foods.

• Accumulating evidence suggests that consuming sugary beverages and foods plays a role in the development of diabetes.

• Artificial sweeteners may be metabolically active and increase the risk for obesity and diabetes.

• Substituting a glass of water for a sugary beverage may be one way to decrease the risk of diabetes.

References:

1. US Food and Drug Administration. FDA revises proposed Nutrition Facts label rule to include a daily value for added sugars. July 24, 2015. Accessed October 23, 2015 at: http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm455837.htm

2. Aubrey A. No more hidden sugar: FDA proposes new label rule. NPR. Accessed October 26 2015 at: http://www.npr.org/sections/thesalt/2015/07/24/425908798/no-more-hidden-sugar-fda-proposes-new-label-rule

3. US Food and Drug Administration. Factsheet on the new proposed nutrition facts label. Accessed October 23, 2015 at: http://www.fda.gov/Food/GuidanceRegulation/GuidanceDocumentsRegulatoryInformation/LabelingNutrition/ucm387533.htm

4. Basu S, et al. The relationship of sugar to population-level diabetes prevalence: an econometric analysis of repeated cross-sectional data . PLOS. 27 Feb 2013.

5. Imamura F, et al. Consumption of sugar sweetened beverages, artificially sweetened beverages, and fruit juice and incidence of type 2 diabetes: systematic review, meta-analysis, and estimation of population attributable fraction. BMJ. 2015 Jul 21;351:h3576.

6. O'Connor L, et al. Prospective associations and population impact of sweet beverage intake and type 2 diabetes, and effects of substitutions with alternative beverages. Diabetologia. 2015 Jul;58(7):1474-1483.

7. Pepino MY. Metabolic effects of non-nutritive sweeteners. Physiol Behav. 2015 Jun 19. pii: S0031-9384(15)00372-8.

8. Suez J, et al. Artificial sweeteners induce glucose intolerance by altering the gut microbiota. Nature. 2014 Oct 9;514(7521):181-186.