On almost every list of the 10 Healthiest Foods, soy has an honored spot. No wonder. Soy has been promoted as nothing less than a magic bean—with the power to prevent heart disease, slow bone loss, ward off certain cancers, and ease the discomforts of menopause.

Does soy deserve its superfood reputation? Not long ago, the American Heart Association convened a top-level scientific advisory panel to find out. The experts reviewed dozens of the most recent findings on soy. Their conclusion? Almost all of soy’s health benefits have been overrated.

Lower cholesterol? In 1999, the FDA gave foods that contain at least 6.25 grams of soy protein per serving the green light to boast that they lower cholesterol and help prevent heart disease. According to recent randomized trials, though, soy may not be delivering on its promise. Yes, it reduces low-density lipoprotein, or LDL cholesterol. But only a mere 3 points, on average. And that’s in people who consume around 50 grams of soy, or about half their total protein. “If you buy a box of cereal with soy added, expecting to lower your LDL and your risk of heart disease, you’re likely to be disappointed,” says Tufts University nutrition researcher Alice Lichtenstein, who was a member of the AHA review panel.

Blood pressure? No benefit from soy, the panel concluded.

Hot flashes during menopause? Only 3 of 8 studies showed any improvement, and even that was modest and short-lived.

Osteoporosis? Soy may slightly lessen bone loss, some studies suggest. But others came up with no benefit, so if there is a benefit, it’s small.

The biggest disappointment: soy doesn’t seem to offer much protection against hormone-related cancers, such as breast, endometrial, and prostate cancer.

Penn State nutrition expert Penny Kris-Etherton, another member of the AHA panel, thinks the new findings are sobering enough that the FDA should reconsider those health claims now allowed on food labels.

That doesn’t mean nutritionists aren’t keen on the bean. Soybeans are a great source of good protein, polyunsaturated fat, and fiber. As an alternative to meat—in a stir fry or a vegetarian burger, for example–soy is a delicious way to reduce saturated fat.

But it’s not a magic bullet. No single food is. That’s the real moral of this particular story of high hopes humbled.

Tags: cholesterol, high blood pressure, hot flashes, osteoporosis, soy, soybeans