Mention the words “cleanse” or “detox,” and many people are likely to react with passion. There are those who swear by it, and many who consider it a sham. The start of the year seems to amplify the conversation, with the list of what people are not eating growing as long and specific as a tally of out-of-season produce.

Last Chance Foods is primarily a segment about healthy and seasonal eating, but January seemed the right time to address the inescapable buzz around cleanses. First of all, the semantics: a “cleanse” can mean everything from the (in)famous liquids-only Master Cleanse to a raw foods–only regimen. “Detox” might be used in reference to laxative-based teas or to refraining from alcohol. These loaded words call for clarification.

To tackle the touchy topic of cleanses, Last Chance Foods spoke with Dr. Alejandro Junger, a cardiologist and the creator of Clean, a 21-day cleanse. The program involves drinking shakes for breakfast and dinner, with a lunch of solid, cleanse-acceptable foods. All Things Considered host Amy Eddings tried the Clean program and says she had a positive experience.

On the other side of the debate is Samantha Heller, a registered dietitian and clinical nutritionist. She asserts that extreme, juice-only cleanses are unhealthy. “It scares the heck out of your body,” says Heller. “Your body thinks it’s starving, so it goes into starvation survival mode and you don’t want your body to have to do that.”

Junger’s program is less extreme because it does allow for solid foods and a full meal every day. Heller explains why she believes people feel better after going through similar cleanse programs. “Any time you shift to a healthier diet, you will feel better,” she says. “So it’s not necessarily the cleansing and the detoxing part of it — which doesn’t actually happen — it’s the dietary shift. Our bodies detox every second of every day. Our bodies are brilliant at it.” Instead, Heller emphasizes that people should focus instead on eating well and exercising.

Junger agrees that humans have built-in systems for detoxing — he cites the elimination of CO2 through breathing as a basic example — but he maintains that those systems sometimes need a boost. “Cleansing and detox programs [are] when somebody creates the conditions for these systems and organs to work harmoniously and efficiently,” he says. “Now, basically what this does [is] it restores your body’s natural ability to heal itself.”

Junger describes fatigue and bloating as signs that a cleanse may be beneficial. “People get what I call ‘puffy’ by retaining so much mucus and water,” he says. Cleanses can also be used to discover food sensitivities through a means of elimination and observation. When reintroducing foods post-cleanse, it’s possible to pinpoint items that upset digestion or cause symptoms like bloating.

While Heller admits that it’s useful to identify food sensitivities, she also voices another criticism of cleanses: the cost. “Cleanses in general, people spend so much money,” she says. “[For the Clean program] in particular, I saw one of the starter programs was $425. You would be so much better off spending that money [on] joining a gym, buying fresh vegetables, buying some beans, buying some cookbooks, maybe even seeing a registered dietitian to help you create a healthier lifestyle plan. And you would still have money left over.”

Junger disagrees and points out that he also wrote a book instructing people on how to make the foods and shakes themselves. Eddings adds that she completed the program without buying the supplements. “The reason I came up with products was not because I wanted to sell something,” Junger says. “It was because I had so many patients that didn’t have the time to go and buy their foods and choose the right vegetables and fruits and juice and... They just didn’t have the time to do it.” He adds that the cost of his program is not necessarily more expensive than 21 days worth of organic fruits and vegetables for breakfast and dinner.

Ultimately, individuals will always disagree on the best ways to maintain healthy lifestyles. Whether cleanses are a part of those efforts or not remains a matter of personal preference. Regardless, at the start of the year and at the end of a discussion on cleanses, it seems worthwhile to reiterate the words made famous by food writer Michael Pollan: “Eat food. Not too much. Mostly plants.”