January 20, 2019

Splenda: Not So Splendid?

by Berkeley Wellness  

If you regularly consume sucralose (such as in Splenda), you may have paid extra attention to headlines earlier this year claiming that this artificial sweetener causes cancer. The news was based on an animal study in the International Journal of Occupational and Environmental Health. Introduced in the U.S. in the late 1990s, sucralose, which is about 600 times sweeter than sucrose (table sugar), is made by processing sucrose into a form that purportedly passes through the gastrointestinal tract [largely] unabsorbed and thus without calories—or biological effects. But questions about its safety have lingered over the years.

What the study said...

The study, from the independent Ramazzini Institute in Italy, fed mice high doses of sucralose throughout their lifespan, beginning prenatally. The higher the dose, the more cancers the male (but not female) mice developed, primarily leukemia. The paper concluded that the data do not support the findings of industry-sponsored studies that sucralose is biologically inert and therefore safe.

In light of the latest findings, the nonprofit consumer advocacy group Center for Science in the Public Interest—which a few years ago changed sucralose’s status from “safe” to “caution”—further demoted the artificial sweetener to its “avoid” category.

Previous research, mostly in animals, has raised concerns as well: that sucralose may alter the balance of bacteria in the gastrointestinal tract (suppressing “beneficial” bacteria more than harmful ones), affect blood sugar and insulin levels (in possibly adverse ways), reduce bioavailability of certain medications, and, when heated, produce potentially toxic substances. Though data in people are limited, a review in the Journal of Toxicity and Environmental Health in 2013, from North Carolina State University and the National Institutes of Health, also contends that sucralose is not “biologically inert” and that the health effects of its metabolites (breakdown products) are not fully known, raising questions about the safety of chronic ingestion.

What the company said...

Not surprisingly, the CEO of the company that makes Splenda slammed the Italian study in an open letter, saying it “contradicts the overwhelming body of scientific research proving the safety of sucralose” and that the amounts used in mice were far greater (the equivalent of 70 to 2,000 cans of diet soda, or 400 to 12,000 packets of Splenda, a day) than what some media outlets reported (equivalent to 10 cans a day). The company also asserts that the Ramazzini Institute “has a history of conducting studies that are not reliable for safety assessment” and that the new study had problems in design and interpretation of findings.

The FDA, Health Canada, EFSA, and World Health Organization have all backed the safety of sucralose, which is approved for use in more than 80 countries. The FDA’s “acceptable daily intake” is 5 milligrams per kilogram body weight; for a 150-pound person, that’s about 28 little yellow packets of Splenda or roughly what’s in 6 to 13 cans of diet soda (depending on the product). The EFSA sets a daily limit three times higher. Consider that the Italian study found adverse effects at doses starting at 240 milligrams per kilogram.

What we say

Despite the media hoopla, the latest study does not provide enough evidence that sucralose is harmful. For one, what happens in lab animals doesn’t necessarily happen in humans (and why only the male mice in the study developed more cancers was not explained by the researchers; other reported data were also ambiguous). And, as we calculated ourselves, the amount of sucralose used in the study far exceeded the amounts that a person could possibly consume. Keep in mind also that this was just one study, compared to the 110 studies that sucralose’s approval for safety was based on.

Still, because there is no long-term data in people to absolutely rule out any adverse effects of chronic intake, moderation is a good idea when it comes to sucralose (as is true for all things in life in general). Besides, there is no definitive evidence that any sugar substitute actually helps with long-term weight control (even if useful for some people, they are hardly a panacea for obesity).

Moreover, if you find yourself using a lot of sugar substitutes, it may be a marker of an unhealthy diet. It’s one thing to use a packet or two in your coffee or tea or to eat an occasional sugar-free treat—but another to be consuming multiple packages of sucralose-containing foods, which tend to be highly processed and often “junk” foods like sugar-free puddings, ice cream, soft drinks, jams, and baked goods. After all, sugar substitutes are not an ingredient in healthy whole foods, like whole grains, legumes, and fresh fruits and vegetables—the types of foods that should make up the bulk of your diet.

Back to sugar?

So should sucralose lovers go back to sugar? We don’t think so. While the adverse effects of sucralose may still be unclear, the many health risks associated with high intakes of added sugar—including obesity, diabetes, and heart disease—are indisputable. A better alternative all around is to cut down on sweets (however they’re sweetened) and opt for water or seltzer (plain or naturally flavored) instead of diet or regular sodas.

Also see Sugar Substitutes: All are Not Equal.