Next time you go grocery shopping, take a closer look at the beverages, yogurt and other packaged foods on display in the store you’re visiting. You’ll most likely find a number of products bearing a special logo and a carefully worded sentence touting their health benefits.
Known as tokuho, short for tokutei hoken-yo shokuhin (foods for specified health uses), these government-certified products come in a bewildering variety of forms: everything from tofu fortified with calcium to strengthen bones and freeze-dried miso soup with dextrin fiber to lower blood-sugar levels, to oolong tea containing polyphenols that are suppose to prevent the accumulation of body fat — to name just a few.
The health ministry-affiliated Japan Health Food & Nutrition Food Association says that the tokuho system is “the first attempt in the world by a nation’s health authorities to approve the display of information about the health effects of a food product on its label.” Tokuho products account for a third of the nation’s 1.9 trillion yen health-food market, logging sales of 629.9 billion yen in fiscal 2005, a fourfold increase since the association first compiled statistics eight years ago. The success of these products is due in part to consumers’ increasing awareness of health issues in recent years, health ministry officials said, and also to deregulation of the screening process in 2003, which made it easier for companies to gain tokuho certification for variations on pre-existing tokuho foods, such as products using different flavorings or sold under different brand names.
The tokuho system was introduced in 1991 by the health ministry to give consumers some measure of guidance amid the plethora of self-described “health foods” on the market, some of which make bogus claims and/or are potentially dangerous to people’s health, said Yoko Kitamura, an official at the ministry’s office of health policy on newly developed foods. She explained that food companies seeking tokuho approval must test the safety and efficacy of their products through “double-blind, randomized” clinical trials on human subjects, and then submit the results to the ministry. As of Nov. 7, the ministry had approved tokuho certification for 604 products.
But tokuho is not without its skeptics, and at least one product — Healthy Econa Cooking Oil, marketed by cosmetic/food business giant Kao Corp. — is now under investigation by the government, following a May 2005 study that concluded a substance called diacylglycerol, featured in the product, might promote cancer.
Kao, which continues to sell the oil, states on its Web site that its own studies, conducted in line with international guidelines, show the product is safe. The product is screened and approved for safety and efficacy in the U.S., Canada, Australia, New Zealand and Taiwan, the firm stresses.
Yoshitaka Tsubono, professor of clinical epidemiology at Tohoku University and a respected researcher in the field of nutrition, said that while the government certification system has some scientific value, consumers must be aware that tokuho products cannot replace treatment with drugs and cannot prevent people from getting sick.
“Tokuho can easily be replaced by eating a balanced diet,” Tsubono said. “You can reduce sugar in your blood, for example, by consuming a lot of fiber — which you can get by eating a lot of vegetables.”
The problem with tokuho products, he points out, is that marketing campaigns have made them appear much more effective than they really are.
“When you look at TV commercials featuring a tokuho cooking oil, for example, you would almost think that it allows you to eat a lot of greasy tonkatsu (deep-fried pork), but the reality is that consuming a lot of calories is bad for you, no matter what oil you use.”
Some experts are even more skeptical. Kuniko Takahashi, professor of home economics at Gunma University and the first academic here to warn people of “food faddism,” has pointed out shortcomings in some of the clinical trials conducted by food companies.
Takahashi cites the case of a drink containing a high concentration of catechin, which is known to help people shed body fat. The product’s manufacturer cites a study published in the September 2002 issue of the Japanese-language journal Progress in Medicine that found that people who kept drinking the product for 12 weeks reduced their average weight and body mass index (BMI) — a measure of body fat calculated by dividing weight by height — from 70.7 kg and 26.5 to 69.0 kg and 25.8, respectively. But Takahashi notes that a man weighing 70 kg can lose that much weight easily — if he simply adds a brisk 20-minute walk to his daily schedule and cuts his daily intake of rice by a mere 60 grams.
In a clinical trial of another product’s ingredients — a special cooking oil called Healthy Resetta — people who were given the product managed to lose 4.5 kg over 12 weeks — but people who were given regular oil also shed 3.3 kg during the same period, Takahashi pointed out.
“The result shows that, if you eat properly and drink less alcohol, you can lose weight without the special oil,” Takahashi wrote in June in Sakae, a medical journal for diabetics.
The oil is manufactured by Nisshin Oillio Group, Ltd., and rakes in annual sales of 10 billion yen for the company — nearly 10 percent of its cooking-oil business. Kazuyoshi Takizawa, spokesman for Nisshin Oillio, said the company entered the tokuho market because it “considers health as one of the main concepts of our enterprise, along with tastefulness and beauty,” adding that consumers’ attention is firmly on health these days. Asked why people who used regular soybean oil instead of the test oil shed weight in the firm’s clinical study, he acknowledged that it was because those participants “ate meals in a disciplined manner.”
Takizawa disagreed, however, that the limited effects of tokuho foods are often misunderstood by consumers, saying that the cooking-oil’s labeling is in line with what the health ministry permits.
What has made the talk over tokuho all the more controversial is the creation last year of a new category of tokuho foods, called joken-tsuki tokuho (“qualified” tokuho). This label allows makers to tout “conditional” health claims for a product even when the mechanism of its health effects is not proven and/or even when the clinical trials are conducted in a substandard manner.
Tsubono of Tohoku University said he disagrees with this new label, noting that it has “ended up serving the interests of manufacturers only.” But the claims such products are permitted to make is so vague and wordy (for example: “This product contains XX, which might improve your condition in YY ways, though scientific grounds for this don’t necessarily exist.”) that few applications for certification have been made. So far, only one product — a dietary supplement called Tochi Extract, which contains fermented soy beans as a possible means for inhibiting fat uptake in the body — has been approved, Kitamura said.
“It’s seen as not helpful [from a business perspective], to tell you the truth,” she said. But she defended the labeling itself, saying that at least such products have been screened for safety.
So what to do? Tsubono advises consumers not to expect any more from tokuho products than the vague claims on their labels. Those interested in learning more about just what healthy substances the products contain, meanwhile, can access summaries (in Japanese only) of the studies used to get the tokuho stamp from a database located at the Web site of the National Institute of Health and Nutrition (hfnet.nih.go.jp/ ).
And remind yourself once again that food is only part of what makes people healthy — along with exercise and rest, Takahashi says. “Instead of paying as much as 500 yen yen per day to drink a tokuho [slimming] tea three times a day, I would just buy high-quality tea in a season when new leaves are picked, and serve it a little stronger than usual. That way, you can get just as much catechin. And it tastes much better.”
Health in a bottle?
Some of the health claims made by particular tokuho products:
* Improves gastrointestinal health — Calpis Kids/drink (lactobacillus acidophilus and lactobacillus helveticus); Fiber Shokupan Sokai Kenbi/bread (fiber)
* Suitable for people with a high cholesterol level — Rama Proactive/margarine (plant sterols); Kirin Cholestemin/powdered soft drink (plantago psyllium)
* Suitable for those with high blood pressure — Peptide Omiso-shiru/freeze-dry miso soup (peptide); Tochugen EX/tea drink (geniposidic acid)
* Helps keep your teeth healthy — Xylitol Gum (xylitol); Recaldent/gum (casein phosphopeptide-amorphous calcium phosphate nanocomplexes)
* Inhibits the body’s absorption of fat — Healthy Econa Cooking Oil (diacylglycerol); Kuro Uroncha/tea drink (oolong tea polymerized polyphenols)
* Helps keep bones healthy — Tekkotsu Inryo/soft drink (calcium, iron); Calcium Tofu/tofu (calcium)
* Provides extra iron — Kuromame-cha/tea drink (isoflavone)