It never fails. You turn on the TV, start a new podcast, open a web browser, or walk through the supermarket, and you’re bombarded with ads pushing quick fixes to help keep you going in a demanding world: an immune boost here, a hangover cure there, a supplement for your hair or skin, or a little something to help you relax at night.

What’s the evidence that these drink mixes, gummies, probiotics, and powders deliver on their promises? We took a look.

Collagen cash cow?

“My go-to collagen routine is adding Vital Proteins Collagen Peptides in my morning cup of coffee or smoothie—so easy to use,” says Vital Proteins’ Chief Creative Officer, actor Jennifer Aniston, on the company’s website.

“Vital Proteins gives you the boost you need to support healthy hair, skin, nails, bone and joint health,” claims the company.

Collagen—the most abundant protein in our bodies—gives structure to skin, bones, joints, and ligaments. (There is none in hair or nails.) As you age, you make less of it. But don’t assume that mixing collagen powder into your morning smoothie will turn back the clock on your aching knees or crow’s feet.

The collagen you eat doesn’t get shuttled directly from your food to your skin or joints. Your body breaks it down into individual amino acids that can be absorbed. And you can’t direct the amino acids in collagen supplements to make new collagen.

In fact, your skin and joints aren’t lacking collagen’s building blocks. Rather, the machinery that makes collagen just doesn’t work as well as you age. And no amount of pricey collagen powder is going to fix that...Jennifer Aniston or no Jennifer Aniston.

Immune-boosting energy?

“Up to 6 hours of clean, immune boosting energy,” promises Pureboost Immune drink powder’s website.

What’s a “clean” ingredient? Companies get to decide, so it’s just a marketing tool.

What about Pureboost’s “immune boosting” ingredients?

In the best study, elderberry failed to blunt flu symptoms any better than a placebo.

And as for Pureboost’s 1,200 milligrams of vitamin C, the vitamin only cuts the risk of catching a cold in people—think ultramarathoners—who are doing extreme exercise.

The only way to “boost” your immune system is with a vaccine. Don’t be fooled by foods, drinks, or supplements claiming to help.

Money multiplier?

“Make your water work harder,” says Liquid I.V., whose “hydration multiplier” drink powder “hydrates faster than water alone.”

How’s that? “Cellular Transport Technology, or CTT®, is the breakthrough delivery system, used in all of our products, designed to enhance rapid absorption of water and other key ingredients into the bloodstream,” explains the company’s website.

“Liquid I.V. Hydration Multiplier meets all of the ORS standards set by UNICEF and the World Health Organization.”

ORS, or oral rehydration salts, are a mix of sugar, potassium, and sodium. They can rehydrate faster than water alone because they help your intestinal cells absorb more water.

That’s why ORS are used to prevent or treat dehydration due to diarrhea, often in people suffering from an infection like cholera.

But that doesn’t mean you need “3x the electrolytes of traditional sports drinks,” like Liquid I.V. promises.

In fact, you don’t need the electrolytes in ordinary sports drinks, period, unless you’ve been exercising heavily for more than an hour. Water plus the electrolytes in a typical diet are all you need for proper hydration.

Nor do you need the 11 grams of added sugar or the 510 milligrams of sodium (about 20 percent of a day’s max) in each packet of Liquid I.V.

We’ll take our water neat, thanks.

Inner placebo?

“Find inner peace, keep in mind it might look like a gumdrop,” says the ad from Lord Jones, the self-proclaimed “world’s finest purveyors of premium CBD products.”

“CBD promotes calmness and supports relaxation,” says the Lord Jones website, which sells CBD supplements, tinctures, body lotion, and more.

Just don’t expect much relaxation from the 20 milligrams of CBD in Lord Jones’s gumdrops...which will set you back $35 for just nine candies.

In one study—funded by a CBD company—researchers randomly assigned 65 adults to take a placebo or 15 mg of CBD every day. After six weeks, mental clarity, stress, sleep quality, relaxation, and other measures of wellbeing were no different in the CBD takers than in the placebo takers.

That’s the only study that used a low dose of CBD, like the one in Lord Jones. Results on stress and anxiety from studies that gave people high doses—often 600 mg a day—are inconsistent.

In another study, scientists gave 43 healthy adults CBD-free oil on two separate days before they were asked to perform a stressful activity. But on one of the days, the participants were told that they were getting CBD.

Sure enough, the volunteers reported feeling more sedated—though no less anxious or stressed—on the day they thought they had taken CBD. And those who had a strong belief that CBD could lower anxiety reported lower anxiety ratings when they thought they had taken CBD.

So CBD may only bring inner peace if you believe it does.

The fiber brand you trust?

“Delicious gummy formula from the fiber brand you trust,” promises Metamucil’s website.

Just don’t confuse the fiber brand you trust with the fiber you trust.

The fiber in regular Metamucil powder is psyllium husk, which reliably improves regularity and lowers cholesterol. But the fibers in Metamucil Fiber Gummies are inulin and Fibersol (sometimes listed on labels as soluble corn fiber, maltodextrin, or resistant maltodextrin).

And if you’re looking for something that “promotes digestive health,” as the gummies label promises, don’t count on Fibersol or inulin.

There are several ways for a processed fiber like Fibersol or inulin to meet the FDA’s definition of “dietary fiber.” It qualifies if the agency is convinced that it curbs food intake or it improve regularity or blood cholesterol or blood sugar or blood pressure or mineral absorption.

What do Fibersol and inulin do? They can boost calcium absorption.

Bran flakes, anyone?

The greens you need?

Athletic Greens has “75 vitamins, minerals, and whole-food sourced nutrients in one convenient daily serving,” says its website. “It’s all you really need, really.”

Really? A serving of the powder has no vitamin D, only 9 percent of a day’s calcium and 6 percent of a day’s magnesium (½ cup of cooked spinach has 20 percent), and less potassium than a banana. (It’s also got far more biotin and vitamins B-12, C, and E than you need...probably to look impressive.)

Athletic Greens claims to promote gut health, support immunity, boost energy, and help recovery. (Anything else?) But companies can make claims like “promote” or “support” without the rigorous evidence they’d need to say that something can prevent, treat, or cure a disease. Without more convincing evidence, call us skeptical. 

Want the benefits of greens? Eat them. You can buy plenty with the $75 a month you’ll save by forgoing Athletic Greens.

Where’s Zevidence?

“Your first drink of the night for a better tomorrow,” promises ZBiotics.

ZBiotics contains a genetically engineered probiotic that makes the enzyme that breaks down acetaldehyde, a toxic byproduct of alcohol metabolism. Acetaldehyde can cause inflammation and is often blamed for hangovers.

ZBiotics’s promise: Drink the probiotic before you start consuming alcohol, and it will neutralize any errant acetaldehyde. “Now you can confidently enjoy drinking,” promises the company.

Sounds good in theory. But it’s unlikely that ZBiotics will do much “for a better tomorrow”: 

Strike 1: When you drink alcohol, almost all of it is absorbed through your stomach and small intestine into your bloodstream and shuttled to your liver, where roughly 95 percent of it is metabolized. So ZBiotics can only break down the acetaldehyde produced from the small fraction of alcohol in the gut. 

Strike 2: It’s unclear if ZBiotics does anything for the acetaldehyde that remains in the gut. Does the drink’s probiotic even survive its passage through the gut or is it broken down by stomach acid or digestive enzymes? More importantly, did ZBiotics prevent hangovers in clinical trials? We asked the company. It never responded.

Strike 3: Some experts question whether acetaldehyde plays a major role in hangovers. Alcohol itself leads to mild dehydration and boosts inflammation. And it causes fragmented sleep and irritates the stomach lining. Those processes—not just acetaldehyde—may explain the fatigue, headache, grogginess, and nausea of a hangover. 

Nice try, ZBiotics.