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When we're pressed for time, meal prep and healthy portions can very easily fall by the wayside, which makes it tough to stay on track with your weight loss goals. That's when a meal replacement diet might seem like a good idea.
These replacement diets—which come in the form of prepackaged meals or shakes—are easy to prepare, low in calories, and fortified with essential vitamins.
"They eliminate some decision-making and allow for structure and control for patients," says Rekha Kumar, MD, MS, a physician at the Comprehensive Weight Control Center at New York-Presbyterian/Weill-Cornell Medical Center.
While these shakes and packaged meals sound convenient, it's hard not to wonder if they're as healthy as they're cracked up to be. So we asked the experts—read on for their take. (And if you do consider one of these programs, consult a physician and/or a registered dietitian first.)
They can be a useful weight loss tool.
Here's the thing: They work. Studies have shown that meal replacement plans can be an effective catalyst in initial weight loss. "There is a place for these when people initiate diets and have trouble with decision making or meal preparation," says Kumar. If you have no idea where to start with your diet, meal replacement plans can be a helpful way to focus your efforts and limit your calorie intake, since, according to Kumar, many of them contain just 250 to 350 calories per meal. (Want to pick up some healthier habits? Sign up to get weight loss inspiration and more delivered straight to your inbox!)
Other medical needs might make these programs a smart bet.
If you have other medical concerns that would require you to lose weight quickly and by a deadline, meal replacement diets might be a healthy option. "For example, I have patients that need a hip replacement and their doctors will say, 'I'm not going to replace your hip unless you lose 30 pounds,'" says Kumar. When weight loss needs to be achieved for a medical procedure to occur, then many patients are motivated to use these programs because it will improve their quality of life.
It can provide a great sense of community.
These meal-replacement diets might help keep you accountable. "That's certainly where some of these programs benefit—you're put on a team, given a social media group, or given a coach," says Torey Armul, MS, RD, spokesperson for the Academy of Nutrition and Dietetics. This community aspect can be beneficial for maintaining weight loss momentum and staying committed as the weeks go on. In fact, initial studies have shown that support groups—specifically social media groups—have been successful at promoting weight loss.
They're not regulated by the FDA.
Keep in mind that many of these products aren't regulated, which could be cause for concern because these products contain added supplements. This means that "what's on the label might not necessarily be what's in the product," says Kristi King, MPH, RDN, spokesperson for the Academy of Nutrition and Dietetics. King cautions that some of these products could even interfere with some patients' medications. That being said, there are a few programs that are safely recognized by the Diabetes Prevention Program.
These diets might not be the most sustainable long-term option.
And that's because life gets in the way. "At some point people have to incorporate themselves into the real world," says Kumar. And in the real world, these meals might not always be readily available and they might become too expensive. Plus, Armul adds, these diets don't teach the foundations of a healthy diet, which is another major reason they aren't sustainable.
Intermittent use might be the way to go.
Instead of using these products for every meal, consider using them every now and then. "Rather than making your whole diet a meal replacement, choose one meal a day," says Armul. If you use them along with a healthy diet, you can eventually start to wean off of them. This slow taper is important, because you'll be learning how to make healthy food choices in the process.
It's essential to think about what comes next.
A meal replacement diet is never the end goal. "There needs to be a plan in place for when the meal replacement plan ends," says Kumar. Once you complete the program, it's important to create a support network to help you continue to move forward. Kumar suggests assembling a team of professionals to help you, and recommends consulting a physician, a registered dietician, and even a psychologist to transition off of these meal replacement products and safely continue your weight loss journey.
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