The Ralph Nader-inspired nutrition-nanny organization, the Center for Science in the Public Interest (CSPI), this week proclaimed that sodas -- sugar-sweetened and diet versions -- pose a health hazard, particularly to children, and warrant cigarette-style warning labels. The report, "Liquid Candy: How Soft Drinks Are Harming America's Health," charges that soda consumption increases the risks of ailments ranging from heart disease to tooth decay, osteoporosis, cancer, obesity, and poor nutrition.
In the course of proclaiming soda "junk food," CSPI has relied on rhetoric, emotion, and junk science (as CSPI often does). Consumers -- and particularly worried parents -- should consider some scientific background information that puts the CSPI charges in perspective:
CSPI, in its attack on soft drinks, is well aware that food and nutrition are highly emotionally charged issues. When they add a focus on children's health, the emotion is ratcheted up even more. We all want our children to be healthy. We, as parents, are vulnerable to those who tell us that our kids are in jeopardy -- whether the claim is about alleged "toxins" in the environment -- or unhealthy food. As a result, many American parents will take note of the CSPI claims and conclude that soft drinks are "bad."
But what are the facts? How do the CSPI charges that soft drinks threaten health hold up under scientific scrutiny?
Soft drinks and dental caries: It is the sticky sugars in food, not sugared liquids, that are particularly important in promoting tooth decay. Parents concerned about preventing tooth decay (in addition to insisting on fluoridated water and professional fluoride treatments) should be aware of the impact that foods such as raisins and dates can have in promoting tooth decay -- if consumption is not followed by tooth brushing.
Soda and obesity: Soft drinks contribute to obesity in exactly the same way that any other source of calories does. Ironically, CSPI, while declaring its concern about obesity, misleads consumers by suggesting that fruit juices are a better choice for those who want to reduce caloric intake -- when, of course, juices often have the same or higher caloric content as soda.
The obvious response to any parent who is worried about children getting excess calories from soda is to switch to diet soda, which is clearly a more logical alternative for dealing with obesity concerns than is a switch to fruit juice. But CSPI does not endorse diet soda, instead implying that sodas with artificial sweeteners are not safe -- in keeping with their overall anti-chemical agenda.
Diet sodas and health risks: Perhaps the most reckless and insidious claim CSPI makes in addressing the alleged health hazard of soda is that the artificial sweeteners used in diet sodas are unsafe. Specifically, the group charges that saccharin has been shown to cause cancer both in humans and rodents -- and then, for good measure, they throw in the charge that aspartame (NutraSweet) has been insufficiently studied.
Both charges are false:
Saccharin, when fed to rodents at huge doses, has indeed been shown to increase the risk of tumors in one strain of male rat. But a significant collection of human studies, many of which focused on diabetics who had consumed unusually large amounts of saccharin, found no link with human cancer. In making the charge that saccharin causes bladder cancer, CSPI cites one aberrant study labeled "preliminary."
NutraSweet (aspartame) is probably one of the most studied food additives in history -- and, with the exception of those with PKU (a relatively rare inherited condition that requires restriction of many sources of dietary protein), there is no evidence that aspartame poses any health hazard.
Diet soda and heart disease: In what has to be the ultimate stretch in linking a variable with disease, CSPI claims that those who eat a diet high in sugar are at higher risk of heart disease -- in much the same way cigarette smokers elevate their risk of heart disease by smoking. This comparison is preposterous. Consuming sugar in any form as part of a well-balanced diet does not generally pose a threat to health. And once again, if one is concerned about total calories, the option of diet soda is a very viable one -- but one rejected by CSPI.
Diet and osteoporosis: CSPI argues that diets low in calcium may for some people increase the risk of bone loss, or osteoporosis, later in life. And certainly that can be true. But this reality is hardly a convincing basis for the argument that soda is a cause of bone loss. Soda is never meant to replace milk and other dairy products. The key is balance and variety. One cannot help but wonder, in considering CSPI's concern about kids and adults not getting enough calcium, if the organization plans to endorse consumption of low-calorie 7-Up Plus, the relatively new soft drink that comes fortified with calcium and vitamin C. I for one doubt it.
The bottom line in pondering soft drinks in the context of good nutrition and health is this: soda is mainly water -- and thus a good source of hydration. All of us need calories for energy -- the problem is not the calories per se but that many of us consume too many of them. Instead of categorizing foods, such as soft drinks, as "good" or "bad," we need to use common sense and follow the cliche: everything in moderation.
Dr. Elizabeth M. Whelan is president of the American Council on Science and Health.
See also: ACSH's full report on activist groups making headlines with dubious health claims, Good Stories, Bad Science.