Watch the commercials or read the ads and you’ll start to think that, at least for older adults, the secret to a long and healthy life can be found in a bottle of Boost, Ensure or another brand of what are known as liquid nutritional supplements.

With taglines reading “Stay strong, stay active” and “Nutrition in charge,” they’re marketed as an easy, do-it-yourself way to stay vigorous as you age.

“They’re seen by many people as something they can do without a prescription for good measure as you get older,” said Dr. Paul Mulhausen, chief medical officer for the Iowa-based health management firm Telligen.

The milkshake-like drinks, which are high in calories and contain vitamins, minerals and other nutrients, originally were developed for hospital patients who were at risk of becoming malnourished because they were unable to eat regular food.

Over time, however, the manufacturers of these drinks (Abbott for Ensure, Nestlé for Boost) have looked to expand the market for them. Hence, they’re now sold in supermarkets and advertised on TV with commercials featuring muscle-bound, anthropomorphic bottles and silver-haired seniors vigorously walking the dog and kneeling down to hug their grandchildren.

But many medical experts question the benefits of, and need for, these supplement drinks.

For example, in its Choosing Wisely recommendations released in February, the American Geriatrics Society advised against using high-calorie supplements in the “medically ill or frail elderly.” The recommendation noted that while these drinks (as well as prescription appetite stimulants) may help older folks gain weight, there’s no proof they improve quality of life, mood, functioning or even survival rates.

(Choosing Wisely, by the way, is an intriguing campaign intended to raise red flags about questionable medical tests, products and procedures and to spark dialogue between physicians and patients. To date, almost 60 medical groups representing more than 1 million providers have developed lists of things physicians and providers should question. To see all the lists, visit choosingwisely.org).

The Choosing Wisely recommendations were intended specifically for the elderly ill. But at the geriatric society’s annual scientific meeting in May, Mulhausen took aim at the use of these drinks by those who are otherwise healthy, according to The New Old Age blog in The New York Times.

Noting that the primary ingredients in these drinks are water, several types of sugar, oils and flavoring, he described them as ”liquid candy bars with vitamins.”

An 8-ounce serving of Ensure Original “milk chocolate” nutrition shake, for example, contains 9 grams of protein, 26 vitamins and minerals and 220 calories. But it also has no fiber and 15 grams of sugar. The same size bottle of Boost Original in “rich chocolate” has a similar nutrition profile but also contains 240 calories and a whopping 28 grams of sugar. That’s almost twice as much as two frosted strawberry Pop-Tarts.

Weight loss can be a red flag for the elderly. Many have trouble eating enough healthy food. They have difficulty shopping for and preparing meals, there may be a medical condition that forces them to eat an unappealing low-salt diet or they may live alone and don’t want to eat because mealtimes are lonely and boring.

But relying on nutrition in a bottle isn’t the answer, Mulhausen told the Express-News. Instead, they (or their family or caregivers) should make the effort to find ways to prepare real, whole foods.

“Real food is not only more palatable than these overly sweet liquid supplements,” he said, “It’s also a better source of calories and micronutrients you don’t get from highly processed food, such as liquid supplements.”